U.S. patent application number 13/095490 was filed with the patent office on 2012-11-01 for supplying treated exhaust gases for effecting growth of phototrophic biomass.
This patent application is currently assigned to POND BIOFUELS INC.. Invention is credited to Jaime A. Gonzalez, Max Kolesnik, Steven C. Martin.
Application Number | 20120276633 13/095490 |
Document ID | / |
Family ID | 47068183 |
Filed Date | 2012-11-01 |
United States Patent
Application |
20120276633 |
Kind Code |
A1 |
Gonzalez; Jaime A. ; et
al. |
November 1, 2012 |
SUPPLYING TREATED EXHAUST GASES FOR EFFECTING GROWTH OF
PHOTOTROPHIC BIOMASS
Abstract
There is provided a process for growing a phototrophic biomass
in a reaction zone. The process includes treating an operative
carbon dioxide supply-comprising gaseous material feed so as to
effect production of a carbon dioxide-rich product material. The
carbon dioxide concentration of the carbon dioxide-rich product
material is greater than the carbon dioxide concentration of the
operative carbon dioxide supply-comprising gaseous material feed.
Production of at least a fraction of the operative carbon dioxide
supply-comprising gaseous material feed is effected by a gaseous
exhaust material producing process. At least a fraction of the
carbon dioxide-rich product material is supplied to the reaction
zone so as to effect growth of the phototrophic biomass by
photosynthesis in the reaction zone.
Inventors: |
Gonzalez; Jaime A.;
(Oakville, CA) ; Kolesnik; Max; (Toronto, CA)
; Martin; Steven C.; (Toronto, CA) |
Assignee: |
POND BIOFUELS INC.
Scarborough
CA
|
Family ID: |
47068183 |
Appl. No.: |
13/095490 |
Filed: |
April 27, 2011 |
Current U.S.
Class: |
435/420 ;
435/243; 435/257.1; 47/1.4 |
Current CPC
Class: |
C12N 5/04 20130101; A01G
33/00 20130101; C12M 21/02 20130101; C12N 1/12 20130101; C07K
14/472 20130101; C12M 43/04 20130101; Y02C 10/04 20130101; Y02C
20/40 20200801; C12M 41/34 20130101 |
Class at
Publication: |
435/420 ;
435/257.1; 435/243; 47/1.4 |
International
Class: |
C12N 1/12 20060101
C12N001/12; C12N 1/00 20060101 C12N001/00; A01G 1/00 20060101
A01G001/00; C12N 5/04 20060101 C12N005/04 |
Claims
1. A process for growing a phototrophic biomass in a reaction zone
comprising: treating an operative carbon dioxide supply-comprising
gaseous material feed so as to effect production of a carbon
dioxide-rich product material wherein the carbon dioxide
concentration of the carbon dioxide-rich product material is
greater than the carbon dioxide concentration of the operative
carbon dioxide supply-comprising gaseous material feed, wherein
production of at least a fraction of the operative carbon dioxide
supply-comprising gaseous material feed is effected by a gaseous
exhaust material producing process; and supplying at least a
fraction of the carbon dioxide-rich product material to the
reaction zone so as to effect growth of the phototrophic biomass by
photosynthesis in the reaction zone.
2. The process of claim 1, wherein the treating of the operative
carbon dioxide supply-comprising gaseous material feed includes
effecting separation, from a separation process feed material, of a
carbon dioxide-rich separation fraction; wherein the separation
process feed material is defined by at least a fraction of the
operative carbon dioxide supply-comprising gaseous material feed;
and wherein the carbon dioxide-rich product material includes the
carbon dioxide-rich separation fraction.
3. The process of claim 2, wherein the ratio of [moles of carbon
dioxide within the carbon dioxide-rich separation fraction] to
[moles of the one or more other materials of the separation process
feed material within the carbon dioxide-rich separation fraction]
is greater than the ratio of [moles of carbon dioxide within the
separation process feed material] to [moles of the one or more
other materials of the separation process feed material within the
separation process feed material].
4. The process of claim 3, wherein the effecting separation, from a
separation process feed material, of a carbon dioxide-rich
separation fraction, includes: effecting dissolution of at least a
fraction of the carbon dioxide of the separation process feed
material so as to effect production of a carbon dioxide-comprising
liquid solution product including dissolved carbon dioxide;
effecting release of a gaseous carbon dioxide-rich intermediate
from a carbon dioxide-comprising liquid solution product feed such
that a carbon dioxide-comprising mixture is provided including the
gaseous carbon dioxide-rich intermediate, wherein the carbon
dioxide-comprising liquid solution feed includes at least a
fraction of the carbon dioxide-comprising liquid solution product,
wherein the gaseous carbon dioxide-rich intermediate includes at
least a fraction of the dissolved carbon dioxide of the carbon
dioxide-comprising liquid solution product; and separating a
gaseous carbon dioxide-rich recovery product from the gaseous
carbon dioxide-rich intermediate, wherein the carbon dioxide
separation fraction includes at least a fraction of the gaseous
carbon dioxide-rich recovery product.
5. The process of claim 4, wherein the effecting release of a
gaseous carbon dioxide-rich intermediate from the carbon
dioxide-comprising liquid solution feed includes effecting release
of at least a fraction of the dissolved carbon dioxide from the
carbon dioxide-comprising liquid solution feed.
6. The process of claim 5, wherein the effecting release of at
least a fraction of the dissolved carbon dioxide from the carbon
dioxide-comprising liquid solution feed includes effecting an
increase in temperature of the carbon dioxide-comprising liquid
solution feed.
7. The process of claim 4, wherein the effecting dissolution
includes effecting dissolution by contacting the separation process
feed material with an operative dissolution agent within a
contacting zone.
8. The process of claim 7, wherein the one or more other materials
of the separation process feed material includes at least one
relatively less soluble material, wherein, relative to carbon
dioxide, each one of the at least one relatively less soluble
material is less soluble within the operative dissolution agent,
when the operative dissolution agent is disposed within the
contacting zone.
9. The process of claim 8, wherein the at least one relatively less
soluble material includes at least one of N.sub.2, O.sub.2, and
CO.
10. The process of claim 8, wherein the contacting effects
production of an intermediate operative carbon dioxide
supply-comprising mixture including a carbon dioxide-comprising
solution intermediate, wherein the carbon dioxide-comprising
solution intermediate includes dissolved carbon dioxide.
11. The process of claim 10, further comprising effecting
separation of the carbon dioxide-comprising liquid solution product
from the intermediate operative carbon dioxide supply-comprising
mixture, wherein the carbon dioxide-comprising liquid solution
product includes at least a fraction of the carbon
dioxide-comprising solution intermediate.
12. The process of claim 11, wherein the effecting separation of
the carbon dioxide-comprising liquid solution product from the
intermediate operative carbon dioxide supply-comprising mixture
includes separation effected by gravity separation.
13. The process of claim 11, wherein each one of (i) the
dissolution of at least a fraction of the carbon dioxide of the
separation process feed material, and (ii) the separation of the
carbon dioxide-comprising liquid solution product from the
intermediate operative carbon dioxide supply-comprising mixture, is
effected in a contacting zone.
14. The process of claim 13, wherein the carbon dioxide-comprising
liquid solution feed is supplied to a carbon dioxide recovery zone
to effect the release of a gaseous carbon dioxide-rich intermediate
from the carbon dioxide-comprising liquid solution feed within the
carbon dioxide recovery zone; and wherein the temperature of the
contacting zone is lower than the temperature of the carbon dioxide
recovery zone.
15. The process of claim 14, wherein at least a fraction of the
operative dissolution agent is supplied to the contacting zone in
the form of a mist.
16. The process of claim 1, wherein the concentration of carbon
dioxide within the separation process feed material is at least two
volume % based on the total volume of the separation process feed
material.
17. The process of claim 4, wherein at least a fraction of the
carbon dioxide-rich separation fraction is flowed through an
eductor prior to being supplied to the reaction zone.
18. The process of claim 4, wherein at least a fraction of the
carbon dioxide-rich separation fraction is supplied to the reaction
zone with a prime mover.
19. The process of claim 1, wherein at least a fraction of the
fraction of the carbon dioxide-rich product material being supplied
to the reaction zone is flowed through an eductor prior to being
supplied to the reaction zone.
20. The process of claim 4, wherein the separation process feed
material further includes at least one of SO.sub.X, NO.sub.X, and
NH.sub.3.
21. The process of claim 20, wherein the at least one of SO.sub.X,
NO.sub.X, and NH.sub.3 is supplied by the gaseous exhaust material.
Description
FIELD
[0001] The present disclosure relates to a process for growing
biomass.
BACKGROUND
[0002] The cultivation of phototrophic organisms has been widely
practised for purposes of producing a fuel source. Exhaust gases
from industrial processes have also been used to promote the growth
of phototrophic organisms by supplying carbon dioxide for
consumption by phototrophic organisms during photosynthesis. By
providing exhaust gases for such purpose, environmental impact is
reduced and, in parallel a potentially useful fuel source is
produced. Challenges remain, however, to render this approach more
economically attractive for incorporation within existing
facilities.
SUMMARY
[0003] In one aspect, there is provided a process for growing a
phototrophic biomass in a reaction zone. The process includes
treating an operative carbon dioxide supply-comprising gaseous
material feed so as to effect production of a carbon dioxide-rich
product material. The carbon dioxide concentration of the carbon
dioxide-rich product material is greater than the carbon dioxide
concentration of the operative carbon dioxide supply-comprising
gaseous material feed. Production of at least a fraction of the
operative carbon dioxide supply-comprising gaseous material feed is
effected by a gaseous exhaust material producing process. At least
a fraction of the carbon dioxide-rich product material is supplied
to the reaction zone so as to effect growth of the phototrophic
biomass by photosynthesis in the reaction zone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The process of the preferred embodiments of the invention
will now be described with the following accompanying drawings:
[0005] FIG. 1 is a process flow diagram of an embodiment of the
process.
[0006] FIG. 2 is a schematic illustration of a portion of a fluid
passage of an embodiment of the process.
DETAILED DESCRIPTION
[0007] Reference throughout the specification to "some embodiments"
means that a particular feature, structure, or characteristic
described in connection with some embodiments are not necessarily
referring to the same embodiments. Furthermore, the particular
features, structure, or characteristics may be combined in any
suitable manner with one another.
[0008] Referring to FIG. 1, there is provided a process of growing
a phototrophic biomass in a reaction zone 10. The reaction zone 10
includes a reaction mixture that is operative for effecting
photosynthesis upon exposure to photosynthetically active light
radiation. The reaction mixture includes phototrophic biomass
material, carbon dioxide, and water. In some embodiments, the
reaction zone includes phototrophic biomass and carbon dioxide
disposed in an aqueous medium. Within the reaction zone 10, the
phototrophic biomass is disposed in mass transfer communication
with both of carbon dioxide and water.
[0009] "Phototrophic organism" is an organism capable of
phototrophic growth in the aqueous medium upon receiving light
energy, such as plant cells and micro-organisms. The phototrophic
organism is unicellular or multicellular. In some embodiments, for
example, the phototrophic organism is an organism which has been
modified artificially or by gene manipulation. In some embodiments,
for example, the phototrophic organism is an alga. In some
embodiments, for example, the algae are microalgae.
[0010] "Phototrophic biomass" is at least one phototrophic
organism. In some embodiments, for example, the phototrophic
biomass includes more than one species of phototrophic
organisms.
[0011] "Reaction zone 10" defines a space within which the growing
of the phototrophic biomass is effected. In some embodiments, for
example, the reaction zone 10 is provided in a photobioreactor 12.
In some embodiments, for example, pressure within the reaction zone
is atmospheric pressure.
[0012] "Photobioreactor 12" is any structure, arrangement, land
formation or area that provides a suitable environment for the
growth of phototrophic biomass. Examples of specific structures
which can be used is a photobioreactor 12 by providing space for
growth of phototrophic biomass using light energy include, without
limitation, tanks, ponds, troughs, ditches, pools, pipes, tubes,
canals, and channels. Such photobioreactors may be either open,
closed, partially closed, covered, or partially covered. In some
embodiments, for example, the photobioreactor 12 is a pond, and the
pond is open, in which case the pond is susceptible to uncontrolled
receiving of materials and light energy from the immediate
environments. In other embodiments, for example, the
photobioreactor 12 is a covered pond or a partially covered pond,
in which case the receiving of materials from the immediate
environment is at least partially interfered with. The
photobioreactor 12 includes the reaction zone 10 which includes the
reaction mixture. In some embodiments, the photobioreactor 12 is
configured to receive a supply of phototrophic reagents (and, in
some of these embodiments, optionally, supplemental nutrients), and
is also configured to effect discharge of phototrophic biomass
which is grown within the reaction zone 10. In this respect, in
some embodiments, the photobioreactor 12 includes one or more
inlets for receiving the supply of phototrophic reagents and
supplemental nutrients, and also includes one or more outlets for
effecting the recovery or harvesting of biomass which is grown
within the reaction zone 10. In some embodiments, for example, one
or more of the inlets are configured to be temporarily sealed for
periodic or intermittent time intervals. In some embodiments, for
example, one or more of the outlets are configured to be
temporarily sealed or substantially sealed for periodic or
intermittent time intervals. The photobioreactor 12 is configured
to contain the reaction mixture which is operative for effecting
photosynthesis upon exposure to photosynthetically active light
radiation. The photobioreactor 12 is also configured so as to
establish photosynthetically active light radiation (for example, a
light of a wavelength between about 400-700 nm, which can be
emitted by the sun or another light source) within the
photobioreactor 12 for exposing the phototrophic biomass. The
exposing of the reaction mixture to the photosynthetically active
light radiation effects photosynthesis and growth of the
phototrophic biomass. In some embodiments, for example, the
established light radiation is provided by an artificial light
source 14 disposed within the photobioreactor 12. For example,
suitable artificial lights sources include submersible fiber optics
or light guides, light-emitting diodes ("LEDs"), LED strips and
fluorescent lights. Any LED strips known in the art can be adapted
for use in the photobioreactor 12. In the case of the submersible
LEDs, in some embodiments, for example, energy sources include
alternative energy sources, such as wind, photovoltaic cells, fuel
cells, etc. to supply electricity to the LEDs. Fluorescent lights,
external or internal to the photobioreactor 12, can be used as a
back-up system. In some embodiments, for example, the established
light is derived from a natural light source 16 which has been
transmitted from externally of the photobioreactor 12 and through a
transmission component. In some embodiments, for example, the
transmission component is a portion of a containment structure of
the photobioreactor 12 which is at least partially transparent to
the photosynthetically active light radiation, and which is
configured to provide for transmission of such light to the
reaction zone 10 for receiving by the phototrophic biomass. In some
embodiments, for example, natural light is received by a solar
collector, filtered with selective wavelength filters, and then
transmitted to the reaction zone 10 with fiber optic material or
with a light guide. In some embodiments, for example, both natural
and artificial lights sources are provided for effecting
establishment of the photosynthetically active light radiation
within the photobioreactor 12.
[0013] "Aqueous medium" is an environment that includes water. In
some embodiments, for example, the aqueous medium also includes
sufficient nutrients to facilitate viability and growth of the
phototrophic biomass. In some embodiments, for example,
supplemental nutrients may be included such as one of, or both of,
NO.sub.X and SO.sub.X. Suitable aqueous media are discussed in
detail in: Rogers, L. J. and Gallon J. R. "Biochemistry of the
Algae and Cyanobacteria," Clarendon Press Oxford, 1988; Burlew,
John S. "Algal Culture: From Laboratory to Pilot Plant." Carnegie
Institution of Washington Publication 600. Washington, D.C., 1961
(hereinafter "Burlew 1961"); and Round, F. E. The Biology of the
Algae. St Martin's Press, New York, 1965; each of which is
incorporated herein by reference). A suitable supplemental nutrient
composition, known as "Bold's Basal Medium", is described in Bold,
H. C. 1949, The morphology of Chlamydomonas chlamydogama sp. nov.
Bull. Torrey Bot. Club. 76: 101-8 (see also Bischoff, H. W. and
Bold, H. C. 1963. Phycological Studies IV Some soil algae from
Enchanted Rock and related algal species, Univ. Texas Publ. 6318:
1-95, and Stein, J. (ED.) Handbook of Phycological Methods, Culture
methods and growth measurements, Cambridge University Press, pp.
7-24).
[0014] The process includes supplying the reaction zone 10 with
carbon dioxide derived from a gaseous exhaust material 14 being
discharged by a gaseous exhaust material producing process 16. The
gaseous exhaust material 14 includes carbon dioxide, and the carbon
dioxide of the gaseous exhaust material defines produced carbon
dioxide.
[0015] In some embodiments, for example, the gaseous exhaust
material 14 includes a carbon dioxide concentration of at least two
(2) volume % based on the total volume of the gaseous exhaust
material 14. In some embodiments, for example, the gaseous exhaust
material 14 includes a carbon dioxide concentration of at least
four (4) volume % based on the total volume of the gaseous exhaust
material 14. In some embodiments, for example, the gaseous exhaust
material reaction 14 also includes one or more of N.sub.2,
CO.sub.2, H.sub.2O, O.sub.2, NO.sub.x, SO.sub.x, CO, volatile
organic compounds (such as those from unconsumed fuels) heavy
metals, particulate matter, and ash. In some embodiments, for
example, the gaseous exhaust material 14 includes 30 to 60 volume %
N.sub.2, 5 to 25 volume % O.sub.2, 2 to 50 volume % CO.sub.2, and 0
to 30 volume % H.sub.2O, based on the total volume of the gaseous
exhaust material 14. Other compounds may also be present, but
usually in trace amounts (cumulatively, usually less than five (5)
volume % based on the total volume of the gaseous exhaust material
14).
[0016] In some embodiments, for example, the gaseous exhaust
material 14 includes one or more other materials, other than carbon
dioxide, that are beneficial to the growth of the phototrophic
biomass within the reaction zone 10. Materials within the gaseous
exhaust material which are beneficial to the growth of the
phototrophic biomass within the reaction zone 10 include SO.sub.X,
NO.sub.X, and NH.sub.3.
[0017] In some embodiments, for example, a supplemental nutrient
supply 18 is supplied to the reaction zone 10. In some embodiments,
for example, the supplemental nutrient supply 18 is effected by a
pump, such as a dosing pump. In other embodiments, for example, the
supplemental nutrient supply 18 is supplied manually to the
reaction zone 10. Nutrients within the reaction zone 10 are
processed or consumed by the phototrophic biomass, and it is
desirable, in some circumstances, to replenish the processed or
consumed nutrients. A suitable nutrient composition is "Bold's
Basal Medium", and this is described in Bold, H. C. 1949, The
morphology of Chlamydomonas chlamydogama sp. nov. Bull. Torrey Bot.
Club. 76: 101-8 (see also Bischoff, H. W. and Bold, H. C. 1963,
Phycological Studies IV Some soil algae from Enchanted Rock and
related algal species, Univ. Texas Publ. 6318: 1-95, and Stein, J.
(ED.) Handbook of Phycological Methods, Culture methods and growth
measurements, Cambridge University Press, pp. 7-24). The
supplemental nutrient supply 18 is supplied for supplementing the
nutrients provided within the reaction zone, such as "Bold's Basal
Medium", or one or more dissolved components thereof. In this
respect, in some embodiments, for example, the supplemental
nutrient supply 18 includes "Bold's Basal Medium". In some
embodiments for example, the supplemental nutrient supply 18
includes one or more dissolved components of "Bold's Basal Medium",
such as NaNO.sub.3, CaCl.sub.2, MgSO.sub.4, KH.sub.2PO.sub.4, NaCl,
or other ones of its constituent dissolved components.
[0018] In some of these embodiments, the rate of supply of the
supplemental nutrient supply 18 to the reaction zone 10 is
controlled to align with a desired rate of growth of the
phototrophic biomass in the reaction zone 10. In some embodiments,
for example, regulation of nutrient addition is monitored by
measuring any combination of pH, NO.sub.3 concentration, and
conductivity in the reaction zone 10.
[0019] In some embodiments, for example, a supply of the
supplemental aqueous material supply 20 is effected to the reaction
zone 10 so as to replenish water within the reaction zone 10 of the
photobioreactor 12. In some embodiments, for example, and as
further described below, the supplemental aqueous material supply
20 effects the discharge of product from the photobioreactor 12 by
displacement. For example, the supplemental aqueous material supply
20 effects the discharge of product from the photobioreactor 12 as
an overflow.
[0020] In some embodiments, for example, the supplemental aqueous
material is water or substantially water. In some embodiments, for
example, the supplemental aqueous material supply 20 includes at
least one of: (a) aqueous material that has been condensed from the
supplied exhausted carbon dioxide while the supplied exhausted
carbon dioxide is being cooled before being supplied to the
contacting zone 34, and (b) aqueous material that has been
separated from a discharged phototrophic biomass-comprising product
202 (see below). In some embodiments, for example, the supplemental
aqueous material supply 20 is derived from an independent source
(i.e., a source other than the process), such as a municipal water
supply 203.
[0021] In some embodiments, for example, the supplemental aqueous
material supply 20 is supplied from a container that has collected
aqueous material recovered from discharges from the process, such
as: (a) aqueous material that has been condensed from the supplied
exhausted carbon dioxide while the supplied exhausted carbon
dioxide is being cooled before being supplied to the contacting
zone, and (b) aqueous material that has been separated from a
discharged phototrophic biomass-comprising product 202. In some
embodiments, for example, the container is in the form of a
settling column 212 (see below).
[0022] In some embodiments, for example, the supplemental nutrient
supply 18 is mixed with the supplemental aqueous material 20 to
provide a nutrient-enriched supplemental aqueous material supply
22, and the nutrient-enriched supplemental aqueous material supply
22 is supplied to the reaction zone 10. In some embodiments, for
example, the supplemental nutrient supply 18 is mixed with the
supplemental aqueous material 20 within the container which has
collected the discharged aqueous material. In some embodiments, for
example, the supply of the nutrient-enriched supplemental aqueous
material supply 18 is effected by a pump.
[0023] An operative carbon dioxide supply-comprising gaseous
material feed is provided. The operative carbon dioxide
supply-comprising gaseous material feed includes carbon dioxide and
one or more other materials. The operative carbon dioxide
supply-comprising gaseous material feed includes at least a
fraction of the gaseous exhaust material 14, and the at least a
fraction of the gaseous exhaust material 14 of the operative carbon
dioxide supply-comprising gaseous material feed defines supplied
gaseous exhaust material. The carbon dioxide that is supplied to
the operative carbon dioxide supply-comprising gaseous material
feed from the gaseous exhaust material producing process 16 defines
supplied exhausted carbon dioxide. The supplied exhausted carbon
dioxide is defined by at least a fraction of the produced carbon
dioxide. The carbon dioxide of the operative carbon dioxide
supply-comprising gaseous material feed includes supplied exhausted
carbon dioxide. In some embodiments, for example, the carbon
dioxide of the operative carbon dioxide supply-comprising gaseous
material feed is defined by the supplied exhausted carbon dioxide.
In some embodiments, for example, the operative carbon dioxide
supply-comprising gaseous material feed is defined by supplied
gaseous exhaust material.
[0024] In some embodiments, for example, the operative carbon
dioxide supply-comprising gaseous material feed includes one or
more other materials supplied from the gaseous exhaust material 14,
other than carbon dioxide, that are beneficial to the growth of the
phototrophic biomass within the reaction zone 10. Examples of such
materials include SO.sub.X, NO.sub.X, and NH.sub.3.
[0025] The gaseous exhaust material producing process 16 includes
any process which effects production and discharge of the gaseous
exhaust material 14. In some embodiments, for example, at least a
fraction of the gaseous exhaust material 14 being discharged by the
gaseous exhaust material producing process 16 is supplied to the
reaction zone 10. The at least a fraction of the gaseous exhaust
material 14, being discharged by the gaseous exhaust material
producing process 16, and supplied to the reaction zone 10,
includes carbon dioxide derived from the gaseous exhaust material
producing process 16. In some embodiments, for example, the gaseous
exhaust material producing process 16 is a combustion process. In
some embodiments, for example, the combustion process is effected
in a combustion facility. In some of these embodiments, for
example, the combustion process effects combustion of a fossil
fuel, such as coal, oil, or natural gas. For example, the
combustion facility is any one of a fossil fuel-fired power plant,
an industrial incineration facility, an industrial furnace, an
industrial heater, or an internal combustion engine. In some
embodiments, for example, the combustion facility is a cement
kiln.
[0026] The operative carbon dioxide supply-comprising gaseous
material feed is treated so as to effect production of a carbon
dioxide-rich product material 26. In some embodiments, the carbon
dioxide-rich product material 26 is gaseous. The carbon dioxide of
the carbon dioxide-rich product material 26 defines concentrated
reaction zone supply carbon dioxide. The carbon dioxide
concentration of the carbon dioxide-rich product material 26 is
greater than the carbon dioxide concentration of the operative
carbon dioxide supply-comprising gaseous material feed. The carbon
dioxide-rich product material 26 includes at least a fraction of
the supplied exhausted carbon dioxide, such that the concentrated
reaction zone supply carbon dioxide includes at least a fraction of
the supplied exhausted carbon dioxide. In some embodiments, the
concentrated reaction zone supply carbon dioxide is defined by at
least a fraction of the supplied exhausted carbon dioxide. As such,
the carbon dioxide-rich product material 26 includes at least a
fraction of the produced carbon dioxide, such that the concentrated
reaction zone supply carbon dioxide includes at least a fraction of
produced carbon dioxide. In some embodiments, the concentrated
reaction zone supply carbon dioxide is defined by at least a
fraction of the produced carbon dioxide.
[0027] In some embodiments, for example, the carbon dioxide-rich
product material 26 includes one or more other materials supplied
from the gaseous exhaust material 14, other than carbon dioxide,
that are beneficial to the growth of the phototrophic biomass
within the reaction zone 10. Examples of such materials include
SO.sub.X, NO.sub.X, and NH.sub.3.
[0028] In some embodiments, the treating of the operative carbon
dioxide supply-comprising gaseous material feed includes effecting
separation, from a separation process feed material 24, of a carbon
dioxide-rich separation fraction 28. The separation process feed
material 24 is defined by at least a fraction of the operative
carbon dioxide supply-comprising gaseous material feed 24. The
carbon dioxide-rich product material 26 includes at least a
fraction of the carbon dioxide-rich separation fraction 28. In some
embodiments, for example, the carbon dioxide-rich separation
fraction 28 is gaseous. The carbon dioxide of the carbon
dioxide-rich separation fraction 28 includes at least a fraction of
the supplied exhausted carbon dioxide, and, in some embodiments,
for example, is defined by at least a fraction of the supplied
exhausted carbon dioxide. As such, the carbon dioxide of the carbon
dioxide-rich separation fraction 28 includes at least a fraction of
the produced carbon dioxide, and, in some embodiments, for example,
the carbon dioxide of the carbon dioxide-rich separation fraction
28 is defined by at least a fraction of the produced carbon
dioxide. In some embodiments, for example, the carbon dioxide-rich
separation fraction 28 includes one or more other materials
supplied from the gaseous exhaust material 14, other than carbon
dioxide, that are beneficial to the growth of the phototrophic
biomass within the reaction zone 10. Examples of such materials
include SO.sub.X, NO.sub.X, and NH.sub.3.
[0029] In some embodiments, for example, the separation process
feed material 24 includes one or more other materials, other than
carbon dioxide. In some embodiments, for example, the one or more
other materials of the separation process feed material 24 are
supplied from the gaseous exhaust material 14 and are beneficial to
the growth of the phototrophic biomass within the reaction zone 10.
Examples of such materials include SO.sub.X, NO.sub.X, and
NH.sub.3.
[0030] The ratio of [moles of carbon dioxide within the carbon
dioxide-rich separation fraction 28] to [moles of the one or more
other materials of the separation process feed material 24 within
the carbon dioxide-rich separation fraction 28] is greater than the
ratio of [moles of carbon dioxide within the separation process
feed material 24] to [moles of the one or more other materials of
the separation process feed material 24 within the separation
process feed material 24]. In some embodiments, for example, the
concentration of carbon dioxide within the carbon dioxide-rich
fraction 28 is greater than the concentration of carbon dioxide
within the separation process feed material 24.
[0031] The carbon dioxide-rich product material 26 includes at
least a fraction of the carbon dioxide of the carbon dioxide-rich
separation fraction 28, such that the concentrated reaction zone
supply carbon dioxide includes at least a fraction of the carbon
dioxide of the carbon dioxide-rich separation fraction 28. In some
embodiments, for example, the concentrated reaction zone supply
carbon dioxide is defined by at least a fraction of the carbon
dioxide of the carbon dioxide-rich separation fraction 28.
[0032] In some embodiments, for example, the effecting separation,
from the separation process feed material, of a carbon dioxide-rich
separation fraction 28, includes contacting the separation process
feed material 24 with an operative solvation (or dissolution) agent
30, so as to effect production of an intermediate operative carbon
dioxide supply-comprising mixture 32 including dissolved carbon
dioxide. The contacting effects solvation (or dissolution) of at
least a fraction of the supplied exhausted carbon dioxide within
the operative solvation agent, and thereby effects production of
the dissolved carbon dioxide. In some embodiments, for example, the
contacting also effects solvation (or dissolution) of at least a
fraction of the one or more other materials within the separation
process feed material 24. In some embodiments, for example, the one
or more other materials that are solvated (or dissolved) are
beneficial to the growth of the phototrophic biomass within the
reaction zone 10. Examples of such materials include SO.sub.X,
NO.sub.X, and NH.sub.3.
[0033] The intermediate operative carbon dioxide supply-comprising
mixture 32 includes a carbon dioxide-comprising solution
intermediate, wherein the carbon dioxide-comprising solution
intermediate includes the dissolved carbon dioxide. The dissolved
carbon dioxide includes at least a fraction of the supplied
exhausted carbon dioxide, and, in some embodiments, is defined by
at least a fraction of the supplied exhausted carbon dioxide. In
this respect, the dissolved carbon dioxide includes at least a
fraction of the produced carbon dioxide, and in some embodiments,
is defined by at least a fraction of the produced carbon dioxide.
In some embodiments, for example, the carbon dioxide-comprising
solution intermediate also includes the one or more other materials
supplied by the separation process feed material 24 that are
solvated (or dissolved) and that are beneficial to the growth of
the phototrophic biomass within the reaction zone 10. Examples of
such materials include SO.sub.X, NO.sub.X, and NH.sub.3.
[0034] It is understood that the contacting may also effect
solvation (or dissolution) of at least a fraction of the one or
more other materials of the separation process feed material 24,
but only to an extent that the above-described relationship of the
ratio of [moles of carbon dioxide within the carbon dioxide-rich
separation fraction 28] to [moles of the one or more other
materials of the separation process feed material 24 within the
carbon dioxide-rich separation fraction 28] and the ratio of [moles
of carbon dioxide within the separation process feed material 24]
to [moles of the one or more other materials of the separation
process feed material within the separation process feed material
24] is maintained.
[0035] The contacting also effects production of a carbon
dioxide-depleted gaseous intermediate, such that the intermediate
operative carbon dioxide supply-comprising mixture 32 includes the
carbon dioxide-depleted gaseous intermediate. The carbon
dioxide-depleted gaseous intermediate includes a fraction of the
separation process feed material 24. The ratio of [moles of carbon
dioxide within the separation process feed material 24] to [moles
of the other one or more materials of the separation process feed
material 24 within the separation process feed material feed 24] is
greater than the ratio of [moles of carbon dioxide within the
carbon dioxide-depleted gaseous intermediate] to [moles of the
other one or more materials of the separation process feed material
24 within the carbon dioxide-depleted gaseous intermediate].
[0036] In some embodiments, for example, the contacting of the
separation process feed material 24 with an operative solvation (or
dissolution) agent 26 effects solvation (or dissolution) of a
fraction of the separation process feed material 24 such that a
material depleted operative carbon dioxide supply-comprising
gaseous material feed is provided, and the material depleted
operative carbon dioxide supply-comprising gaseous material feed
includes, and, in some embodiments, is defined by, the carbon
dioxide-depleted gaseous intermediate.
[0037] In some embodiments, for example, the one or more other
materials of the separation process feed material 24 includes at
least one relatively less soluble material. Relative to carbon
dioxide, each one of the at least one relatively less soluble
material is less soluble within the operative solvation (or
dissolution) agent, when the operative solvation (or dissolution)
agent is disposed within the contacting zone. Examples of the
relatively less soluble material include N.sub.2, O.sub.2, and
CO.
[0038] In some embodiments, for example, the contacting is effected
in a contacting zone 34.
[0039] In some embodiments, for example, the operative solvation
(or dissolution) agent 30 is aqueous material. In some embodiments,
for example, the operative solvation (or dissolution) agent 30 is
water or substantially water, and the contacting is effected in a
contacting zone 34 including a pressure of between 10 psia and 25
psia and a temperature of between two (2) degrees Celsius and four
(4) degrees Celsius. In some embodiments, for example, the pressure
is atmospheric and the temperature is three (3) degrees
Celsius.
[0040] In some embodiments, for example, the operative solvation
(or dissolution) agent 30 is provided within the contacting zone 34
in the form of a mist by supplying the operative solvation (or
dissolution) agent 34 to the contacting zone 34 through a spray
nozzle 36. In some embodiments, for example, the spray nozzle 36
includes a plurality of substantially uniformly spaced-apart
nozzles to maximize volumetric exchange of gas into the water
droplets. Providing the operative solvation (or dissolution) agent
30 in the form of a mist increases the contact surface area between
the operative solvation (or dissolution) agent 30 and the
separation process feed material 24 being contacted. In some
embodiments, for example, the operative solvation (or dissolution)
agent discharging from the spray nozzle 36 includes a droplet size
of between 10 and 2000 microns. In some embodiments, the operative
solvation (or dissolution) agent 30 is discharged through the spray
nozzle 36 at a temperature of between two (2) degrees Celsius and
four (4) degrees Celsius. In some embodiments, for example, the
temperature of the discharged operative solvation (or dissolution)
agent is three (3) degrees Celsius.
[0041] In some embodiments, for example, the contacting zone 34 is
provided within a contacting tank 38. In some embodiments, for
example, the contacting tank 38 contains a contacting zone liquid
material 40 disposed within the contacting zone. In some
embodiments, for example, the contacting zone liquid material 40
includes a vertical extent of between one (1) foot and five (5)
feet. In some embodiments, for example, the contacting zone liquid
material 40 is disposed at the bottom of the contacting tank 38.
The contacting zone liquid material 40 includes the operative
solvation (or dissolution) agent 30. In some embodiments, for
example, the contacting zone liquid material 40 includes at least a
fraction of the operative solvation (or dissolution) agent 30 that
has been introduced to the contacting zone 34 through the spray
nozzle 36. In some of these embodiments, for example, the
contacting zone liquid material 40 includes at least a fraction of
the operative solvation (or dissolution) agent 30 that has been
introduced to the contacting zone 34 through the spray nozzle 36
and has collected at the bottom of the contacting zone tank 38. In
some embodiments, for example, the contacting zone liquid material
40 includes at least a fraction of the carbon dioxide-comprising
solution intermediate. In some of these embodiments, for example,
the contacting zone liquid material 40 includes carbon
dioxide-comprising solution intermediate that has collected at the
bottom of the contacting zone tank 38. The separation feed material
24 is flowed through the contacting zone liquid material 40 upon
its introduction to the contacting zone 34. In some embodiments,
for example, the separation feed material 24 is introduced to the
contacting zone liquid material 40 through a sparger.
[0042] Separation of a carbon dioxide-comprising liquid solution
product 42 is effected from the intermediate operative carbon
dioxide supply-comprising mixture 32. The carbon dioxide-comprising
liquid solution product 42 includes at least a fraction of the
carbon dioxide-comprising solution intermediate, and, in some
embodiments, is defined by at least a fraction of the carbon
dioxide-comprising solution intermediate, such that the carbon
dioxide-comprising liquid solution product 42 includes at least a
fraction of the supplied exhausted carbon dioxide, and, in this
respect, includes at least a fraction of the produced carbon
dioxide. In this respect, the carbon dioxide of the carbon
dioxide-comprising liquid solution product 42 includes at least a
fraction of the supplied exhausted carbon dioxide, and, in some
embodiments, is defined by at least a fraction of the supplied
exhausted carbon dioxide. Also in this respect, the carbon dioxide
of the carbon dioxide-comprising liquid solution product 42
includes at least a fraction of the produced carbon dioxide, and,
in some embodiments, is defined by at least a fraction of the
produced carbon dioxide.
[0043] In some embodiments, for example, the carbon
dioxide-comprising liquid solution product 42 includes the one or
more other materials supplied by the separation process feed
material 24 that are solvated (or dissolved) within the contacting
zone 34 and that are beneficial to the growth of the phototrophic
biomass within the reaction zone 10. Examples of such materials
include SO.sub.X, NO.sub.X, and NH.sub.3.
[0044] In some embodiments, for example, the carbon
dioxide-comprising liquid solution product 42 includes dissolved
carbon dioxide and at least one of SO.sub.x and NO.sub.x.
[0045] In some embodiments, for example, the separation of the
carbon dioxide-comprising liquid solution product 42 from the
intermediate operative carbon dioxide supply-comprising mixture 32
includes separation by gravity separation. In some embodiments, for
example, the separation is effected in the contacting zone 34.
[0046] In some embodiments, for example, the separation of the
carbon dioxide-comprising liquid solution product 42 from the
intermediate operative carbon dioxide supply-comprising mixture 32
effects separation of a gaseous contacting operation by-product 44
from the carbon dioxide-comprising liquid solution product 42. The
gaseous contacting operation by-product 44 includes at least a
fraction of the carbon dioxide-depleted gaseous intermediate, and,
in some embodiments, for example, is defined by at least a fraction
of the carbon dioxide-depleted gaseous intermediate.
[0047] In some embodiments, for example, in parallel with the
separation of the carbon dioxide-comprising liquid solution product
42 from the intermediate operative carbon dioxide supply-comprising
mixture 32, depletion of the carbon dioxide, and, in some
embodiments, of one or more other materials, from within the
intermediate operative carbon dioxide supply-comprising mixture 32
is effected, such that separation of a material depleted
intermediate operative carbon dioxide supply-comprising mixture
from the carbon dioxide-comprising liquid solution product 42 is
effected, wherein the material depleted intermediate operative
carbon dioxide supply-comprising mixture includes the gaseous
contacting operation by-product 44. In some embodiments, for
example, the material depleted intermediate operative carbon
dioxide supply-comprising mixture is defined by the gaseous
contacting operation by-product 44.
[0048] In some embodiments, for example, the gaseous contacting
operation by-product 44 includes N.sub.2, O.sub.2, and CO. In some
embodiments, for example, the gaseous contacting operation
by-product 44 is discharged from the contacting tank as an exhaust
441.
[0049] In some embodiments, for example, the supplied gaseous
exhaust material, either by itself or as part of the separation
process feed material 24, is cooled prior to the separation of a
carbon dioxide-rich separation fraction 28 from the separation
process feed material 24. In some embodiments, for example, the
supplied gaseous exhaust material is cooled prior to supply to the
contacting zone 34 so as to facilitate the solvation (or the
dissolution) of the carbon dioxide. In some embodiments, for
example, the cooling of the supplied gaseous exhaust material
facilitates the provision of a material supply to the reaction zone
10 with a temperature that is suitable for the growth of the
phototrophic biomass. In some embodiments, for example, the
supplied gaseous exhaust material is disposed at a temperature of
between 110 degrees Celsius and 150 degrees Celsius. In some
embodiments, for example, the temperature of the supplied gaseous
exhaust material is about 132 degrees Celsius. In some embodiments,
the temperature at which the supplied gaseous exhaust material is
disposed is much higher than this, and, in some embodiments, such
as the gaseous exhaust material 14 from a steel mill, the
temperature can be as high as 500 degrees Celsius. In some
embodiments, for example, the cooling is effected so as to
facilitate the solvation (or the dissolution) of the carbon
dioxide. In some embodiments, for example, the supplied gaseous
exhaust material is cooled to 50 degrees Celsius or less (in some
embodiments, for example, this depends on the dew point of the
water vapour within the supplied gaseous exhaust material). In some
of these embodiments, in effecting the cooling of the supplied
gaseous exhaust material, at least a fraction of any water vapour
of the supplied gaseous exhaust material is condensed in a heat
exchanger 46 (such as a condenser) and separated from the supplied
gaseous exhaust material as an aqueous material 201. In some
embodiments, the resulting aqueous material 201 is re-used in the
process. In some embodiments, for example, the resulting aqueous
material 201 is re-used as supplemental aqueous material supply 20.
In some embodiments, for example, the aqueous material is supplied
to the settling column 212 (described below). In some embodiments,
the condensing effects heat transfer from the supplied gaseous
exhaust material to a heat transfer medium 68, thereby raising the
temperature of the heat transfer medium 48 to produce a heated heat
transfer medium 48, and the heated heat transfer medium 48 is then
supplied (for example, flowed) to a dryer 50 (discussed below), and
heat transfer is effected from the heated heat transfer medium 48
to a phototrophic biomass-rich intermediate product that has been
derived from a discharge from the photobioreactor to effect drying
of the phototrophic biomass-rich intermediate product and thereby
effect production of the final reaction zone product 52. In some
embodiments, for example, after being discharged from the dryer 50,
the heat transfer medium 48 is recirculated to the heat exchanger
46. Examples of a suitable heat transfer medium 48 include thermal
oil and glycol solution.
[0050] Release of a gaseous carbon dioxide-rich intermediate from a
carbon dioxide-comprising liquid solution feed 42A is effected. The
carbon dioxide-comprising liquid solution feed 42A includes at
least a fraction of the carbon dioxide-comprising liquid solution
product 42. In some embodiments, the carbon dioxide-comprising
liquid solution feed 42A is defined by at least a fraction of the
carbon dioxide-comprising liquid solution product. The gaseous
carbon dioxide-rich intermediate includes at least a fraction of
the dissolved carbon dioxide of the carbon dioxide-comprising
liquid solution feed 42A. In some embodiments, for example, carbon
dioxide of the gaseous carbon dioxide-rich intermediate is defined
by at least a fraction of the dissolved carbon dioxide of the
carbon dioxide-comprising liquid solution feed 42A. In this
respect, the carbon dioxide of the gaseous carbon dioxide-rich
intermediate includes at least a fraction of the supplied exhausted
carbon dioxide, and, in some embodiments, is defined by at least a
fraction of the supplied exhausted carbon dioxide. Also in this
respect, the carbon dioxide of the gaseous carbon dioxide-rich
intermediate includes at least a fraction of the produced carbon
dioxide, and, in some embodiments, is defined by at least a
fraction of the produced carbon dioxide.
[0051] In some embodiments, for example, the carbon
dioxide-comprising liquid solution feed 42A includes the one or
more other materials supplied by the separation process feed
material 24 that are solvated (or dissolved) and included within
the carbon dioxide-comprising liquid solution product 42, and that
are beneficial to the growth of the phototrophic biomass within the
reaction zone 10. Examples of such materials include SO.sub.X,
NO.sub.X, and NH.sub.3. In this respect, in some embodiments, for
example, the effected release of the gaseous carbon dioxide-rich
intermediate from a carbon dioxide-comprising liquid solution feed
42A includes release of these one or more other materials.
[0052] In some embodiments, for example, the release is effected by
effecting a decrease in the solubility of carbon dioxide within the
carbon dioxide-comprising liquid solution feed 42A. By effecting
the decrease in solubility of the carbon dioxide within the carbon
dioxide-comprising liquid solution feed 42A, carbon dioxide, and,
in some embodiments, one or more other materials dissolved within
the carbon dioxide-comprising liquid solution feed 42A, become
released from each of their respective dissolved relationships or
associations from within the carbon dioxide-comprising liquid
solution feed 42A. In some cases, this release, for each of these
materials is characterized as "effervescence" or "coming out of
solution".
[0053] In some embodiments, for example, the decrease in the
solubility of carbon dioxide within the carbon dioxide-comprising
liquid solution feed 42A is effected by effecting an increase in
the temperature of the carbon dioxide-comprising liquid solution
feed 42A. In some embodiments, for example, the decrease in the
solubility of carbon dioxide within the carbon dioxide-comprising
liquid solution feed 42A is effected by effecting a decrease in the
pressure of the carbon dioxide-comprising liquid solution feed
42A.
[0054] In some embodiments, for example, the release of the gaseous
carbon dioxide-rich intermediate from the carbon dioxide-comprising
liquid solution feed 42A effects formation of a carbon dioxide-lean
liquid intermediate, such that a carbon dioxide-comprising mixture
54 is provided including the gaseous carbon dioxide-rich
intermediate and the carbon dioxide-lean liquid intermediate.
[0055] In some embodiments, for example, in parallel with the
release of the gaseous carbon dioxide-rich intermediate from the
carbon dioxide-comprising liquid solution feed 42A, depletion of
the carbon dioxide, and, in some embodiments, of one or more
materials, from the carbon dioxide-comprising liquid solution feed
42A is effected, such that formation of a material depleted carbon
dioxide-comprising liquid solution feed 42A is effected, wherein
the material depleted carbon dioxide-comprising liquid solution
feed 42A includes the carbon dioxide-lean liquid intermediate. In
some embodiments, for example, the material depleted carbon
dioxide-comprising liquid solution product defines the carbon
dioxide-lean liquid intermediate.
[0056] A gaseous carbon dioxide-rich recovery product 56 is
separated from the carbon dioxide-comprising mixture 54. The
gaseous carbon dioxide-rich recovery product 56 includes at least a
fraction of the gaseous carbon dioxide-rich intermediate, and, in
some embodiments, is defined by at least a fraction of the gaseous
carbon dioxide-rich intermediate, such that the gaseous carbon
dioxide-rich recovery product 56 includes at least a fraction of
the supplied exhausted carbon dioxide, and, in this respect,
includes at least a fraction of the produced carbon dioxide. In
this respect, the carbon dioxide of the gaseous carbon dioxide-rich
recovery product 56 includes at least a fraction of the supplied
exhausted carbon dioxide, and, in some embodiments, is defined by
at least a fraction of the supplied exhausted carbon dioxide. Also
in this respect, the carbon dioxide of the gaseous carbon
dioxide-rich recovery product 56 includes at least a fraction of
the produced carbon dioxide, and, in some embodiments, is defined
by at least a fraction of the produced carbon dioxide.
[0057] In some embodiments, for example, the gaseous carbon
dioxide-rich recovery product 56 includes the one or more other
materials supplied by the separation process feed material 24 that
are solvated (or dissolved) and then supplied within the carbon
dioxide-comprising liquid solution feed 42A, and that are
beneficial to the growth of the phototrophic biomass within the
reaction zone 10. Examples of such materials include SO.sub.X,
NO.sub.X, and NH.sub.3.
[0058] In some embodiments, for example, the gaseous carbon
dioxide-rich recovery product also includes at least one of
SO.sub.x and NO.sub.x In some embodiments, for example, the
concentration of carbon dioxide within the carbon dioxide-rich
recovery product 56 is at least 90 volume % based on the total
volume of the product 56. In some embodiments, for example, the
gaseous carbon dioxide-rich recovery product 56 is substantially
pure carbon dioxide.
[0059] In some embodiments, for example, the separation of the
gaseous carbon dioxide-rich recovery product 56 from the carbon
dioxide-comprising mixture 54 includes separation by gravity
separation. In some embodiments, for example, the separation is
effected in the contacting zone.
[0060] In some embodiments, for example, the separation of the
gaseous carbon dioxide-rich recovery product 56 from the carbon
dioxide-comprising mixture 54 effects separation of a carbon
dioxide-lean liquid product 58 from the gaseous carbon dioxide-rich
recovery product 56. The carbon dioxide-lean liquid product 58
includes at least a fraction of the carbon dioxide-lean liquid
intermediate, and, in some embodiments, for example, is defined by
at least a fraction of the carbon dioxide-lean liquid
intermediate.
[0061] In some embodiments, for example, in parallel with the
separation of the gaseous carbon dioxide-rich recovery product 56
from the carbon dioxide-comprising mixture 54, depletion of the
carbon dioxide, and, in some embodiments, of one or more materials,
from the carbon dioxide-comprising mixture 54 is effected, such
that separation of a material depleted carbon dioxide-comprising
mixture from the gaseous carbon dioxide-rich recovery product 56 is
effected, wherein the material depleted carbon dioxide-comprising
mixture includes the carbon dioxide-lean liquid product 58. In some
embodiments, for example, the material depleted carbon
dioxide-comprising mixture is defined by the carbon dioxide-lean
liquid product 58.
[0062] In some embodiments, for example, the carbon dioxide-lean
liquid product 58 includes carbon dioxide, and in some of these
embodiments, also includes SO.sub.x and NO.sub.x, but, for each of
these, in much smaller concentrations than their corresponding
concentrations in the carbon dioxide-rich recovery product 56.
[0063] The carbon dioxide-rich separation fraction 28 includes at
least a fraction of the gaseous carbon dioxide-rich recovery
product 56. In some embodiments, for example the carbon
dioxide-rich separation fraction 28 is defined by at least a
fraction of the gaseous carbon dioxide-rich recovery product 56. In
this respect, as a corollary, the carbon dioxide-rich separation
fraction 28 includes at least a fraction of the supplied exhausted
carbon dioxide, and, in this respect, includes at least a fraction
of the produced carbon dioxide. Also in this respect, as a
corollary, the carbon dioxide of the carbon dioxide-rich separation
28 includes at least a fraction of the supplied exhausted carbon
dioxide, and, in some embodiments, is defined by at least a
fraction of the supplied exhausted carbon dioxide. Also in this
respect, as a corollary, the carbon dioxide of the carbon
dioxide-rich separation 28 includes at least a fraction of the
produced carbon dioxide, and, in some embodiments, is defined by at
least a fraction of the produced carbon dioxide.
[0064] In some embodiments, for example, the carbon dioxide-rich
separation fraction 28 includes the one or more other materials
supplied by the separation process feed material 24 that are
solvated (or dissolved), then supplied within the carbon
dioxide-comprising liquid solution feed 42A, and then provided
within the gaseous carbon dioxide-rich recovery product 56, and
that are beneficial to the growth of the phototrophic biomass
within the reaction zone 10. Examples of such materials include
SO.sub.X, NO.sub.X, and NH.sub.3.
[0065] In some embodiments, for example, the carbon
dioxide-comprising liquid solution feed 42A is supplied to a carbon
dioxide recovery zone 60, wherein the above-described release of
the gaseous carbon dioxide-rich intermediate from the carbon
dioxide-comprising liquid solution feed 42A is effected in the
carbon dioxide recovery zone 60.
[0066] In some embodiments, for example, the temperature within the
carbon dioxide recovery zone 60 is higher than the temperature of
the contacting zone 34, so as to effect the release of the gaseous
carbon dioxide-rich intermediate from the carbon dioxide-comprising
liquid solution feed 42A. In this respect, in some embodiments, for
example, the temperature within the carbon dioxide recovery zone 60
is higher than the temperature within the contacting zone 34 by at
least 15 degrees Celsius. In some embodiments, for example, this
temperature difference is at least 20 degrees Celsius. In some
embodiments, for example, this temperature difference is at least
25 degrees Celsius. In some embodiments, for example, this
temperature difference is at least 30 degrees Celsius. In this
respect, in those embodiments, where the operative solvation (or
dissolution) agent is an aqueous material, the temperature within
the carbon dioxide recovery zone is at least 17 degrees
Celsius.
[0067] It is understood that the temperature within the carbon
dioxide recovery zone 60 is dependent on the temperature within the
contacting zone 34, as well as on the composition of the separation
fraction 24 to be recovered. The extent of the temperature spread
between the carbon dioxide recovery zone 60 and the contacting zone
34 is dictated by the solubility characteristics of the materials
within the separation fraction 24 to be recovered. In order to
effect the desired solvation (or dissolution) of materials within
the contacting zone 34, and then effect the desired release (or
effervescence) of those same materials within the carbon dioxide
recovery zone 60, for each of these materials, the solubility of
the material within the solvent provided in the carbon dioxide
recovery zone 60 must be sufficiently lower than the solubility of
the same material within the solvent provided in the contacting
zone 34 such that meaningful recovery of such material from the
separation process feed material 24 is effected.
[0068] In some embodiments, for example, the pressure of the carbon
dioxide recovery zone 60 is lower than the pressure of the
contacting zone 34. This also effects the release of the gaseous
carbon dioxide-rich intermediate from the carbon dioxide-comprising
liquid solution feed 42A. In some embodiments, for example, a
vacuum is generated within the recovery zone so as to effect the
release.
[0069] In some embodiments, for example, the carbon
dioxide-comprising liquid solution feed 42A is supplied to a carbon
dioxide recovery zone 60 as a flow. In some embodiments, for
example, the flow of the carbon dioxide-comprising liquid solution
feed 42A is effected by a prime mover, such as a pump. In some
embodiments, for example, flow of the carbon dioxide-comprising
liquid solution feed 42A from the contacting zone 34 to the carbon
dioxide recovery zone 60 is effected by gravity. In some
embodiments, for example, the carbon dioxide-comprising liquid
solution feed 42A from the contacting zone 34 to the carbon dioxide
recovery zone 60 is effected by a prime mover, such as a pump,
whose suction is disposed in fluid communication with the carbon
dioxide recovery zone 60.
[0070] In some embodiments, for example, a heat exchanger 64 is
disposed in thermal communication with the carbon dioxide recovery
zone 60 to effect an increase in the temperature of the carbon
dioxide-comprising liquid solution feed 42A, and thereby effect a
decrease in solubility of the carbon dioxide within the carbon
dioxide-comprising liquid solution feed 42A. In some embodiments,
for example, the carbon dioxide recovery zone 60 is disposed in a
carbon dioxide recovery tank 66, and the heat exchanger 64 is
mounted in thermal communication with the external surface of the
carbon dioxide recovery tank 66.
[0071] In some embodiments, for example, the separation of the
gaseous carbon dioxide-rich recovery product 56 from the carbon
dioxide-comprising mixture 54 is effected in the carbon dioxide
recovery zone 60.
[0072] In some embodiments, for example, the carbon dioxide
recovery tank 66 contains a carbon dioxide recovery zone liquid
material 68 disposed within the carbon dioxide recovery zone 60,
and also includes a headspace 70 disposed above the carbon dioxide
recovery zone liquid material for collecting the gaseous carbon
dioxide-rich recovery product 56. In some embodiments, for example,
the carbon dioxide recovery zone liquid material 68 includes a
vertical extent of at least three (3) feet. In some embodiments,
for example, the vertical extent is at least ten (10) feet. In some
embodiments, for example, this vertical extent is between ten (10)
and twenty (20) feet. In some embodiments, for example, sufficient
volume of carbon dioxide recovery zone liquid material 68 is
provided, and co-operates with a disposition of the outlet for
discharging the liquid material 68, such that sufficient residence
time is provided within the carbon dioxide recovery zone 60 for
effecting the desired release and separation of carbon dioxide from
the liquid material 68 prior to discharge of the liquid material 68
from the carbon dioxide recovery zone 60. The carbon dioxide
recovery zone liquid material 68 includes the material depleted
carbon dioxide-comprising liquid solution product. In some
embodiments, for example, the carbon dioxide recovery zone liquid
material 68 includes a fraction of the carbon dioxide-comprising
liquid solution feed 42A from which carbon dioxide, and, in some
embodiments, one or more other materials, have not been separated.
In some embodiments, for example, the carbon dioxide-comprising
liquid solution feed 42A is supplied to the carbon dioxide recovery
zone 60 by introduction into a lower portion of the carbon dioxide
recovery zone liquid material 68, and is heated by heat that is
thermally communicated to the carbon dioxide recovery zone liquid
material 68 from in and around the lower portion of the carbon
dioxide recovery zone liquid material 68.
[0073] In some embodiments, for example, the gaseous carbon
dioxide-rich recovery product 58 is discharged from the carbon
dioxide recovery tank 66. In some embodiments, for example, the
discharge of the gaseous carbon dioxide-rich recovery product 66
from the headspace 70 of the carbon dioxide recovery tank 66 is
effected with a vacuum. In some embodiments, for example, a vacuum
generated is such that the pressure within the headspace is between
10 and 14.7 psia, and is also lower than the pressure in the
contacting zone 34. In some embodiments, for example, the vacuum is
generated by a prime mover or eductor that is fluidly coupled to
the headspace for effecting supply of at least a fraction of the
gaseous carbon dioxide-rich recovery product 58 to the reaction
zone 10 from the carbon dioxide recovery tank 66.
[0074] In some embodiments, for example, the carbon dioxide
recovery zone liquid material 68 is discharged from the carbon
dioxide recovery zone 60. In some embodiments, the carbon dioxide
recovery zone liquid material 68 is discharged from the carbon
dioxide recovery zone 60 through an outlet of the carbon dioxide
recovery tank 66 disposed proximate to the upper level of the
carbon dioxide recovery zone liquid material 68 within the carbon
dioxide recovery tank 66. In some embodiments, for example, the
outlet is vertically displaced from the upper level of liquid
material 68 no further than 25% of the vertical extent of the
liquid material disposed within the recovery zone 60. In some
embodiments, for example, the outlet is vertically displaced from
the upper level of liquid material 68 no further than 15% of the
vertical extent of the liquid material disposed within the recovery
zone 60. In some embodiments, for example, the outlet is vertically
displaced from the upper level of liquid material 68 no further
than 10% of the vertical extent of the liquid material disposed
within the recovery zone 60. Amongst other things, this mitigates
against short-circuiting of the recovery zone 60 by the material
supplied by the carbon dioxide-comprising liquid solution feed 42A,
which would effectively reduce the residence time of this supplied
material within the carbon dioxide recovery zone 60, and thereby
decreases the proportion of carbon dioxide that undergoes the
above-described release from solution and becomes separated from
the liquid material 68 before being discharged from the outlet of
the tank 66. As well, in some embodiments, for example, the liquid
material 68 disposed closer to the upper level is warmer than the
liquid material disposed closer to the bottom of the recovery zone
60, and carbon dioxide is less likely to be in solution in the
liquid material 68 disposed closer to the upper level relative to
the liquid material disposed closer to the bottom of the recovery
zone 60, thereby further reinforcing the desirability of having the
discharge effected closer to the upper level of the liquid material
68 within the tank 66. In some embodiment, for example, the
discharged carbon dioxide recovery zone liquid material 68 is
recycled to provide at least a fraction of the operative solvation
(or dissolution) agent 30 to the contacting zone 34. In some
embodiments, prior to being introduced into the contacting zone 34,
the discharged carbon dioxide recovery zone liquid material 68 is
cooled so as to effect a reduction in temperature of the discharged
carbon dioxide recovery zone liquid material 68 and thereby render
it suitable for use as at least a fraction of the operative
solvation (or dissolution) agent 30 being supplied to the
contacting zone 34. In this respect, in some embodiments, for
example, the discharged carbon dioxide recovery zone liquid
material 68 is flowed through a chiller 72 for effecting the
reduction in temperature.
[0075] In some embodiments, for example, when the carbon dioxide
recovery tank 66 is of a relatively wider dimension, the
disposition of the outlet relative to the upper level of liquid
material 68 is not as critical, so long as the carbon
dioxide-comprising liquid solution feed 42A is supplied to the
carbon dioxide recovery tank 66 through an inlet that is disposed
substantially opposite relative to the outlet, as sufficient
residence time is more likely to be realized in such a
configuration.
[0076] In some embodiments, for example, the chiller 72 is
thermally coupled to the heat exchanger 64 with a heat transfer
loop that is based on a refrigeration circuit (commercially
available) that extracts heat from the relatively warmer discharged
carbon dioxide recovery zone liquid material 68 flowing through the
chiller to reduce its temperature (for example, to three (3)
degrees Celsius) to maximize the solubility equilibrium of the
soluble gases in the separation process feed material 24. The heat
extracted from the discharged carbon dioxide recovery zone liquid
material 68 is returned to the carbon dioxide recovery 60, to have
the inverse effect and allow the dissolved gases in the carbon
dioxide-comprising liquid solution feed 42A to escape into the
headspace 70 by increasing the temperature of the carbon
dioxide-comprising liquid solution feed 42A, and thereby decreasing
the solubility of the gases that have been previously solvated (or
dissolved).
[0077] At least a fraction of the carbon dioxide-rich product
material 26 is supplied to the reaction zone 10 as a carbon
dioxide-rich product material supply. The reaction zone feed
material 80, being introduced to the reaction zone, includes the
carbon dioxide-rich product material supply. In this respect, the
reaction zone feed material 80 includes at least a fraction of the
carbon dioxide-rich product material 26. In some embodiments, for
example, the reaction zone feed material 80 is defined by at least
a fraction of the carbon dioxide-rich product material 26. In this
respect, as a corollary, the reaction zone feed material includes
carbon dioxide of the carbon dioxide-rich product material 26. As
such, the reaction zone feed material 80 includes at least a
fraction of the supplied exhausted carbon dioxide, and, in this
respect, includes at least a fraction of the produced carbon
dioxide. As a further corollary, the carbon dioxide of the reaction
zone feed material includes at least a fraction of the supplied
exhausted carbon dioxide, and, in this respect, includes at least a
fraction of the produced carbon dioxide. In some embodiments, for
example, the carbon dioxide of this reaction zone feed material 80
is defined by at least a fraction of the supplied exhausted carbon
dioxide, and, in this respect, is defined by the produced carbon
dioxide.
[0078] In some of these embodiments, for example, introduction of
the reaction zone feed material 80 to the reaction zone 10 is
effected while the gaseous exhaust material 14 is being discharged
by the gaseous exhaust material producing process 16.
[0079] In some embodiments, for example, the pressure of the carbon
dioxide-rich product material supply is increased before being
supplied to the reaction zone 10. In some embodiments, for example,
the pressure increase is at least partially effected by a prime
mover 76. For those embodiments where the carbon dioxide-rich
product material supply 26 is disposed within a liquid-comprising
material, a suitable prime mover 76 is, for example, a pump. For
those embodiments where the carbon dioxide-rich product material
supply is disposed within a gaseous material, suitable prime movers
76 include, for example, blowers, compressors, and air pumps. In
other embodiments, for example, the pressure increase is effected
by a jet pump or eductor.
[0080] With respect to such embodiments, where the pressure
increase is effected by a jet pump or eductor, in some of these
embodiments, for example, the carbon dioxide-rich product material
supply is supplied to the jet pump or eductor and pressure energy
is transferred to the reaction zone carbon dioxide feed material
from another flowing fluid (the "motive fluid flow") using the
venturi effect to effect a pressure increase in the carbon
dioxide-rich product material supply. In this respect, in some
embodiments, for example, and referring to FIG. 2, a motive fluid
flow 100 is provided, wherein material of the motive fluid flow 100
includes a motive fluid pressure P.sub.M1. In this respect also, a
lower pressure state reaction zone feed-comprising material 300 is
provided including a pressure P.sub.E, wherein the lower pressure
state reaction zone feed comprising material 300 includes the
carbon dioxide-rich product material supply. In some embodiments,
the lower pressure state reaction zone feed-comprising material is
defined by the carbon dioxide-rich product material supply.
P.sub.M1 of the motive fluid flow is greater than P.sub.E of the
lower pressure state reaction zone feed-comprising material.
Pressure of the motive fluid flow 100 is reduced from P.sub.M1 to
P.sub.M2, such that P.sub.m2 is less than P.sub.E, by flowing the
motive fluid flow 100 from an upstream fluid passage portion 102 to
an intermediate downstream fluid passage portion 104. The
intermediate downstream fluid passage portion 104 is characterized
by a smaller cross-sectional area relative to the upstream fluid
passage portion 102. By flowing the motive fluid flow from the
upstream fluid passage portion 102 to the intermediate downstream
fluid passage portion 104, static pressure energy is converted to
kinetic energy. When the pressure of the motive fluid flow 100 has
becomes reduced to P.sub.M2, fluid communication between the motive
fluid flow 100 and the lower pressure state reaction zone
feed-comprising material 300 is effected such that the lower
pressure state reaction zone feed-comprising material 300 is
induced to mix with the motive fluid flow 100 in the intermediate
downstream fluid passage portion 104, in response to the pressure
differential between the lower pressure state reaction zone
feed-comprising material 300 and the motive fluid flow 100, to
produce an intermediate reaction zone feed-comprising material 302
which includes the carbon dioxide-rich product material supply.
Pressure of the intermediate reaction zone feed-comprising material
302, which includes the carbon dioxide-rich product material
supply, is increased to P.sub.M3, such that the pressure of the
carbon dioxide-rich product material supply is also increased to
P.sub.M3. P.sub.M3 is greater than P.sub.E and is also sufficient
to effect supply of the carbon dioxide-rich product material supply
to the reaction zone 10 and, upon supply of the carbon dioxide-rich
product material supply to the reaction zone 10 as at least a
fraction of the reaction zone feed material 80, effect flow of the
carbon dioxide-rich product material supply through a vertical
extent of reaction mixture within the reaction zone 10 of at least
a seventy (70) inches. In some embodiments, for example, P.sub.M3
is greater than P.sub.E and is also sufficient to effect supply of
the carbon dioxide-rich product material supply to the reaction
zone 10 and, upon supply of the carbon dioxide-rich product
material supply to the reaction zone 10, effect flow of the carbon
dioxide-rich product material supply through a vertical extent of
reaction mixture within the reaction zone 10 of at least 10 feet.
In some embodiments, for example, P.sub.M3 is greater than P.sub.E
and is also sufficient to effect supply of the carbon dioxide-rich
product material supply to the reaction zone 10 and, upon supply of
the carbon dioxide-rich product material supply to the reaction
zone 10, effect flow of the carbon dioxide-rich product material
supply through a vertical extent of reaction mixture within the
reaction zone 10 of at least 20 feet. In some embodiments, for
example, P.sub.M3 is greater than P.sub.E and is also sufficient to
effect supply of the carbon dioxide-rich product material supply to
the reaction zone 10 and, upon supply of the carbon dioxide-rich
product material supply to the reaction zone 10, effect flow of the
carbon dioxide-rich product material supply through a vertical
extent of reaction mixture within the reaction zone 10 of at least
30 feet. In any of these embodiments, the pressure increase is
designed to overcome the fluid head within the reaction zone 10.
The pressure increase is effected by flowing the intermediate
reaction zone feed-comprising material 302 from the intermediate
downstream fluid passage portion 104 to a "kinetic energy to static
pressure energy conversion" downstream fluid passage portion 106.
The cross-sectional area of the "kinetic energy to static pressure
energy conversion" downstream fluid passage portion 106 is greater
than the cross-sectional area of the intermediate downstream fluid
passage portion 104, such that kinetic energy of the intermediate
reaction zone feed-comprising material 302 disposed in the
intermediate downstream fluid passage portion 104 is converted into
static pressure energy when the intermediate reaction zone
feed-comprising material 302 becomes disposed in the "kinetic
energy to static pressure energy conversion" downstream fluid
passage portion 106 by virtue of the fact that the intermediate
reaction zone feed-comprising material 302 has become flowed to a
fluid passage portion with a larger cross-sectional area. In some
embodiments, for example, a converging nozzle portion of a fluid
passage defines the upstream fluid passage portion 102 and a
diverging nozzle portion of the fluid passage defines the "kinetic
energy to static pressure energy conversion" downstream fluid
passage portion 106, and the intermediate downstream fluid passage
portion 104 is disposed intermediate of the converging and
diverging nozzle portions. In some embodiments, for example, the
combination of the upstream fluid passage portion 102 and the
"kinetic energy to static pressure energy conversion" downstream
fluid passage portion 106 is defined by a venture nozzle. In some
embodiments, for example, the combination of the upstream fluid
passage portion 102 and the "kinetic energy to static pressure
energy conversion" downstream fluid passage portion 106 is disposed
within an eductor or jet pump. In some of these embodiments, for
example, the motive fluid flow includes liquid aqueous material
and, in this respect, the intermediate reaction zone
feed-comprising material 302 includes a combination of liquid and
gaseous material, and includes the carbon dioxide-rich product
material supply. In this respect, in some embodiments, for example,
the intermediate reaction zone feed-comprising material 302
includes a dispersion of a gaseous material within a liquid
material, wherein the dispersion of a gaseous material includes the
carbon dioxide-rich product material supply. Alternatively, in some
of these embodiments, for example, the motive fluid flow is another
gaseous flow, such as an air flow, and the intermediate reaction
zone feed-comprising material 302 is gaseous. After pressure of the
intermediate reaction zone feed-comprising material has been
increased to P.sub.M3, the supply of the carbon dioxide-rich
product material by the intermediate reaction zone feed-comprising
material 302 to the reaction zone feed material 80 is effected.
[0081] The reaction mixture disposed in the reaction zone 10 is
exposed to photosynthetically active light radiation so as to
effect photosynthesis. The photosynthesis effects growth of the
phototrophic biomass.
[0082] In some embodiments, for example, the light radiation is
characterized by a wavelength of between 400-700 nm. In some
embodiments, for example, the light radiation is in the form of
natural sunlight. In some embodiments, for example, the light
radiation is provided by an artificial light source. In some
embodiments, for example, light radiation includes natural sunlight
and artificial light.
[0083] In some embodiments, for example, the intensity of the
provided light is controlled so as to align with the desired growth
rate of the phototrophic biomass in the reaction zone 10. In some
embodiments, regulation of the intensity of the provided light is
based on measurements of the growth rate of the phototrophic
biomass in the reaction zone 10. In some embodiments, regulation of
the intensity of the provided light is based on the molar rate of
supply of carbon dioxide to the reaction zone feed material 80.
[0084] In some embodiments, for example, the light is provided at
pre-determined wavelengths, depending on the conditions of the
reaction zone 10. Having said that, generally, the light is
provided in a blue light source to red light source ratio of 1:4.
This ratio varies depending on the phototrophic organism being
used. As well, this ratio may vary when attempting to simulate
daily cycles. For example, to simulate dawn or dusk, more red light
is provided, and to simulate mid-day condition, more blue light is
provided. Further, this ratio may be varied to simulate artificial
recovery cycles by providing more blue light.
[0085] It has been found that blue light stimulates algae cells to
rebuild internal structures that may become damaged after a period
of significant growth, while red light promotes algae growth. Also,
it has been found that omitting green light from the spectrum
allows algae to continue growing in the reaction zone 10 even
beyond what has previously been identified as its "saturation
point" in water, so long as sufficient carbon dioxide and, in some
embodiments, other nutrients, are supplied.
[0086] With respect to artificial light sources, for example, a
suitable artificial light source 14 includes submersible fiber
optics, light-emitting diodes, LED strips and fluorescent lights.
Any LED strips known in the art can be adapted for use in the
process. In the case of the submersible LEDs, the design includes
the use of solar powered batteries to supply the electricity. In
the case of the submersible LEDs, in some embodiments, for example,
energy sources include alternative energy sources, such as wind,
photovoltaic cells, fuel cells, etc. to supply electricity to the
LEDs.
[0087] With respect to those embodiments where the reaction zone 10
is disposed in a photobioreactor 12 which includes a tank, in some
of these embodiments, for example, the light energy is provided
from a combination of sources, as follows. Natural light source 16
in the form of solar light is captured though solar collectors and
filtered with custom mirrors that effect the provision of light of
desired wavelengths to the reaction zone 10. The filtered light
from the solar collectors is then transmitted through light guides
or fiber optic materials into the photobioreactor 12, where it
becomes dispersed within the reaction zone 10. In some embodiments,
in addition to solar light, the light tubes in the photobioreactor
12 contains high power LED arrays that can provide light at
specific wavelengths to either complement solar light, as
necessary, or to provide all of the necessary light to the reaction
zone 10 during periods of darkness (for example, at night). In some
embodiments, with respect to the light guides, for example, a
transparent heat transfer medium (such as a glycol solution) is
circulated through light guides within the photobioreactor 12 so as
to regulate the temperature in the light guides and, in some
circumstances, provide for the controlled dissipation of heat from
the light guides and into the reaction zone 10. In some
embodiments, for example, the LED power requirements can be
predicted and, therefore, controlled, based on trends observed with
respect to the gaseous exhaust material 18, as these observed
trends assist in predicting future growth rate of the phototrophic
biomass.
[0088] In some embodiments, the exposing of the reaction mixture to
photosynthetically active light radiation is effected while the
supplying of the reaction zone carbon dioxide feed material is
being effected.
[0089] In some embodiments, for example, the growth rate of the
phototrophic biomass is dictated by the available reaction zone
carbon dioxide supply material. In turn, this defines the nutrient,
water, and light intensity requirements to maximize phototrophic
biomass growth rate. In some embodiments, for example, a
controller, e.g. a computer-implemented system, is provided to be
used to monitor and control the operation of the various components
of the process disclosed herein, including lights, valves, sensors,
blowers, fans, dampers, pumps, etc.
[0090] Reaction zone product is discharged from the reaction zone.
The reaction zone product includes phototrophic biomass-comprising
product 58. In some embodiments, for example, the phototrophic
biomass-comprising product 58 includes at least a fraction of the
contents of the reaction zone 10. In this respect, the discharge of
the reaction zone product effects harvesting of the phototrophic
biomass 202. In some embodiments, for example, the reaction zone
product also includes a reaction zone gaseous effluent product 204
that is discharged within the exhaust 441.
[0091] In some embodiments, for example, the harvesting of the
phototrophic biomass is effected by discharging the phototrophic
biomass 58 from the reaction zone.
[0092] In some embodiments, for example, the discharging of the
phototrophic biomass 58 from the reaction zone 10 is effected by
displacement. In some of these embodiments, for example, the
displacement is effected by supply supplemental aqueous material
supply 20 to the reaction zone 10. In some of these embodiments,
for example, the displacement is an overflow. In some embodiments,
for example, the discharging of the phototrophic biomass 58 from
the reaction zone 10 is effected by gravity. In some embodiments,
for example, the discharging of the phototrophic biomass 58 from
the reaction zone 10 is effected by a prime mover that is fluidly
coupled to the reaction zone 10.
[0093] In some embodiments, for example, the discharge of the
phototrophic biomass-comprising product 202 is effected through an
outlet extending from the reaction mixture within the reaction zone
10 at a vertical level of the reaction mixture that defines less
than 50% of the vertical extent of the reaction mixture within the
reaction zone 10. In some embodiments, for example, the outlet
extends from the reaction mixture within the reaction zone at a
vertical level of the reaction mixture that defines less than 25%
of the vertical extent of the reaction mixture within the reaction
zone 10. In some embodiments, for example, the outlet extends from
the reaction mixture within the reaction zone at a vertical level
of the reaction mixture that defines less than 10% of the vertical
extent of the reaction mixture within the reaction zone 10. In some
embodiments, for example, the outlet extends from the reaction
mixture within the reaction zone at a vertical level of the
reaction mixture that defines less than 5% of the vertical extent
of the reaction mixture within the reaction zone 10. In some
embodiments, for example, the outlet extends from the vertically
lowermost portion of the reaction mixture within the reaction zone
10. In some of these embodiments, for example, the discharging of
the phototrophic biomass-comprising product 202 is effected by
gravity. In some of these embodiments, for example, a prime mover,
such as a pump, is fluidly coupled to the outlet to effect the
discharge of the phototrophic biomass product 202 from the reaction
zone 10. In some embodiments, for example, a rotary air lock valve
(which also functions as a prime mover) is disposed at the outlet
to effect the discharge of the phototrophic biomass product 202
from the reaction zone 10.
[0094] In some embodiments, for example, the molar rate of
discharge of the product 202 is controlled through the molar rate
of supply of supplemental aqueous material supply, which influences
the displacement from the photobioreactor 12 of the phototrophic
biomass-comprising product 202 from an outlet of the
photobioreactor 12. For example, an overflow of an upper portion of
phototrophic biomass suspension in the reaction zone 10 from the
photobioreactor 12 (for example, the phototrophic biomass is
discharged through an overflow port of the photobioreactor 12) is
effected by this displacement to provide the phototrophic
biomass-comprising product 202. In some embodiments, for example,
the discharging of the product 202 is controlled with a prime mover
(such as a pump) fluidly coupled to an outlet of the
photobioreactor 12.
[0095] The phototrophic biomass-comprising product 202 includes
water. In some embodiments, for example, the phototrophic
biomass-comprising product 202 is supplied to a separator system
for effecting removal of at least a fraction of the water from the
phototrophic biomass-comprising product 202 to effect production of
an intermediate concentrated phototrophic biomass-comprising
product (e.g., 208) and a recovered aqueous material 210
(generally, water). In some embodiments, the recovered aqueous
material 210 re-used by the process.
[0096] In some embodiments, for example, the separator system
includes a settling column 212, a decanter 214, and a dryer 50.
[0097] In some embodiments, for example, the discharged
phototrophic biomass-comprising product is supplied to the settling
column 212 under a motive force, such as that supplied by a pump.
In some embodiments, for example, flocculant 216 is added so as to
facilitate settling of the phototrophic biomass within the settling
column 212. In some embodiments, for example, the molar rate of
supply of flocculant to the phototrophic biomass-comprising product
is modulated based on the molar rate of supply of the phototrophic
biomass of the phototrophic biomass-comprising product 202 (which,
for example, can be determined by sensing molar concentration of
phototrophic biomass within the phototrophic biomass-comprising
product 202 in combination with the detection of the molar rate of
flow of the phototrophic biomass-comprising product 202 being
supplied to the settling column 212) to the settling column 212. In
some embodiments, aqueous material 201, which has condensed from
the heat exchanger 46, as well as the aqueous material 2141 which
has been separated from the decanter 214 (see below), is also
supplied to the settling column 212 so as to effect their re-use as
the supplemental aqueous material supply 20. In some embodiments,
for example, liquid level is controlled within the settling column
so as to provide sufficient residence time to effect the desired
settling of a phototrophic biomass-rich first intermediate product
208. In this respect, in some embodiments, for example, upon
determination that a detected liquid level in the settling column
201 is below a predetermined minimum liquid level, water from a
municipal water supply is supplied to the settling column to effect
an increase to the liquid level, such as by effecting opening of a
valve 213. Separation of the phototrophic biomass-rich first
intermediate product 208 from an aqueous liquid overhead product
210 is effected by gravity settling in the settling column. In some
embodiments, for example, the aqueous liquid overhead product 210
is returned to the photobioreactor 12 as the supplemental aqueous
material supply 20 for re-use. In some embodiments, for example,
the supplemental nutrient supply is added to the supplemental
aqueous material supply 20 prior to supply to the photobioreactor.
In some embodiments, for example, the molar rate of supply of the
supplemental aqueous material supply 20 to the photobioreactor 12
is modulated based on a detected molar rate of flow of the carbon
dioxide-rich product material 26 to the reaction zone 10.
[0098] In some embodiments, for example, a level sensor is provided
to detect the level of the reaction mixture within the reaction
zone 10, and transmit a signal representative of the detected level
to a controller. The controller compares the received signal to a
predetermined level value. If the received signal is less than the
predetermined level value, the controller responds by effecting
initiation of supply, or an increase to the molar rate of supply,
of the supplemental aqueous material supply 20 to the reaction zone
10, such as by opening (in the case of initiation of supply), or
increasing the opening (in the case of increasing the molar rate of
supply), of a valve configured to interfere with the supply of the
supplemental aqueous material supply 20 to the reaction zone 10. If
the received signal is greater than the predetermined level value,
the controller responds by effecting a decrease to the molar rate
of supply, or termination of supply, of the supplemental aqueous
material supply 20 to the reaction zone 10, such as by decreasing
the opening of (in the case of decreasing the molar rate of
supply), or closing the valve (in the case of terminating the
supply) that is configured to interfere with the supply of the
supplemental aqueous material supply 20 to the reaction zone 10. In
some embodiments, for example, by regulating the supplying of the
supplemental aqueous material supply 20 to the reaction zone 10 so
as to effect the maintaining of a desired level within the reaction
zone 10, make-up water is supplied to the reaction zone 10 to
replace water that is discharged with the phototrophic
biomass-comprising product 202 with a view to maintaining steady
state conditions within the reaction zone 10.
[0099] In some embodiments, for example, while growth of the
phototrophic biomass is being effected within the reaction mixture
disposed within the reaction zone 10 and exposed to the
photosynthetically active light radiation, discharge of the
phototrophic biomass from the reaction zone 10 is effected at a
molar rate of discharge that is equivalent to, or substantially
equivalent to, a predetermined molar rate of growth of phototrophic
biomass within the reaction mixture which is disposed within the
reaction zone 10 and is being exposed to the photosynthetically
active light radiation. The growth of the phototrophic biomass
includes growth effected by photosynthesis. In some embodiments,
for example, the predetermined molar rate of growth of phototrophic
biomass is at least 90% of the maximum molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass within the reaction zone 10 is at least 95% of the maximum
molar rate of growth of phototrophic biomass within the reaction
mixture which is disposed within the reaction zone 10 and is being
exposed to the photosynthetically active light radiation. In some
embodiments, for example, the predetermined molar rate of growth of
phototrophic biomass is at least 99% of the maximum molar rate of
growth of phototrophic biomass within the reaction mixture which is
disposed within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass is equivalent to the maximum molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the discharging of the phototrophic biomass 58 from the
reaction zone 10 is effected by displacement. In some of these
embodiments, for example, the displacement is effected by supplying
supplemental aqueous material supply 20 to the reaction zone 10. In
some of these embodiments, for example, the displacement is an
overflow. In some embodiments, for example, the discharging of the
phototrophic biomass 58 from the reaction zone 10 is effected by
gravity. In some embodiments, for example, the discharging of the
phototrophic biomass 58 from the reaction zone 10 is effected by a
prime mover that is fluidly coupled to the reaction zone 10.
[0100] In some embodiments, for example, while growth of the
phototrophic biomass is being effected within the reaction mixture
disposed within the reaction zone 10 and exposed to the
photosynthetically active light radiation, the molar rate of
discharge of the phototrophic biomass from the reaction zone 10 is
modulated in response to detection of a difference between a
phototrophic biomass growth indicator, detected from within the
reaction zone 10, and a predetermined phototrophic biomass growth
indicator value. The predetermined phototrophic biomass growth
indicator value is correlated with a predetermined molar rate of
growth of phototrophic biomass within the reaction mixture which is
disposed within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass is based on the maximum molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass is at least 90% of the maximum molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass is at least 95% of the maximum molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass within the reaction mixture is at least 99% of the maximum
molar rate of growth of phototrophic biomass within the reaction
mixture which is disposed within the reaction zone 10 and is being
exposed to the photosynthetically active light radiation. In some
embodiments, for example, the predetermined molar rate of growth of
phototrophic biomass is equivalent to the maximum molar rate of
growth of phototrophic biomass within the reaction mixture which is
disposed within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation. In some embodiments, for
example, the phototrophic biomass growth indicator is a molar
concentration of phototrophic biomass. In some embodiments, for
example, the predetermined molar rate of growth of phototrophic
biomass, with which the predetermined phototrophic biomass growth
indicator value is correlated, is based upon a rate of increase in
molar concentration of phototrophic biomass within the reaction
zone 10 effected by growth of the phototrophic biomass within the
reaction mixture which is disposed within the reaction zone 10 and
is being exposed to the photosynthetically active light
radiation.
[0101] In some embodiments, for example, while the modulating of
the molar rate of discharge of the phototrophic biomass from the
reaction zone 10 is being effected, the volume of the reaction
mixture disposed within the reaction zone is maintained constant or
substantially constant for a time period of at least one (1) hour.
In some embodiments, for example, the time period is at least six
(6) hours. In some embodiments, for example, the time period is at
least 24 hours. In some embodiments, for example, the time period
is at least seven (7) days. In some embodiments, for example, while
the modulating is being effected, the volume of the reaction
mixture disposed within the reaction zone is maintained constant or
substantially constant for the a period of time such that the
predetermined phototrophic biomass growth indicator value, as well
as the predetermined molar rate of growth of phototrophic biomass,
is maintained constant or substantially constant during this
period, with a view to optimizing economic efficiency of the
process.
[0102] In some embodiments, for example, while the modulating of
the molar rate of discharge of the phototrophic biomass from the
reaction zone 10 is being effected, the process further includes
modulating the molar rate of supply of the supplemental nutrient
supply to the reaction zone in response to the detection of a
difference between a detected molar concentration of one or more
nutrients (e.g., NO.sub.3) within the reaction zone 10 and a
corresponding predetermined target molar concentration value. In
some embodiments, for example, the molar rate of supply of the
supplemental nutrient supply to the reaction zone 10 is modulated
in response to a detected change in the molar rate of supply of the
carbon dioxide-rich product material 26 to the reaction zone
10.
[0103] In some embodiments, for example, while the modulating of
the molar rate of discharge of the phototrophic biomass from the
reaction zone 10 is being effected, the process further includes
modulating the molar rate of supply of the carbon dioxide-rich
product material 26 to the reaction zone 10 based on at least one
carbon dioxide processing capacity indicator. In some embodiments,
for example, the detection of at least one of the at least one
carbon dioxide processing capacity indicator is effected in the
reaction zone 10. The carbon dioxide processing capacity indicator
which is detected is any characteristic that is representative of
the capacity of the reaction zone 10 for receiving carbon dioxide
and having at least a fraction of the received carbon dioxide
converted in a photosynthesis reaction effected by phototrophic
biomass disposed within the reaction zone. In some embodiments, for
example, the carbon dioxide processing capacity indicator is a pH
within the reaction zone 10. In some embodiments, for example, the
carbon dioxide processing capacity indicator is a phototrophic
biomass molar concentration within the reaction zone 10.
[0104] In some embodiments, for example, while the modulating of
the molar rate of discharge of the phototrophic biomass from the
reaction zone 10 is being effected, the process further includes
modulating the intensity of the photosynthetically active light
radiation to which the reaction mixture is exposed to, in response
to a detected change in the molar rate at which the carbon
dioxide-rich product material 26 is being supplied to the reaction
zone 10.
[0105] In some embodiments, for example, and as described above,
the discharge of the phototrophic biomass from the reaction zone 10
is effected by a prime mover, such as a pump. In this respect, in
some embodiments, for example, the modulating of the molar rate of
discharge of the phototrophic biomass from the reaction zone
includes:
[0106] (i) modulating the power supplied to the prime mover
effecting the discharge of the phototrophic biomass from the
reaction zone 10 in response to detection of a difference between a
detected phototrophic biomass growth indicator, within the reaction
mixture disposed within the reaction zone, and a predetermined
phototrophic biomass growth indicator value, wherein the
predetermined phototrophic biomass growth indicator target value is
correlated with a predetermined molar rate of growth of
phototrophic biomass within the reaction mixture which is disposed
within the reaction zone 10 and is being exposed to the
photosynthetically active light radiation, and;
[0107] (ii) while the modulating of the power supplied to the prime
mover is being effected, modulating the molar rate of supply of the
supplemental aqueous material supply 20 to the reaction zone 10 in
response to detection of a difference between a detected indication
of volume of reaction mixture within the reaction zone and a
predetermined reaction mixture volume indication value, wherein the
predetermined reaction mixture volume indication value is
representative of a volume of reaction mixture within the reaction
zone 10 within which growth of the phototrophic biomass is effected
within the reaction mixture at the predetermined molar rate of
growth of phototrophic biomass while the phototrophic biomass
growth indicator, within the reaction mixture, is disposed at the
predetermined phototrophic biomass growth indicator target
value.
[0108] In some of these embodiments, for example, the predetermined
molar rate of growth of the phototrophic biomass is based upon the
maximum molar rate of growth of the phototrophic biomass within the
reaction mixture which is disposed within the reaction zone 10 and
is being exposed to the photosynthetically active light radiation,
as described above.
[0109] In some embodiments, for example, the phototrophic biomass
growth indicator is a molar concentration of phototrophic
biomass.
[0110] In some embodiments, for example, the indication of volume
of reaction mixture within the reaction zone 10 (or, simply, the
"reaction mixture volume indication") is an upper liquid level of
the reaction mixture within the reaction zone 10. In some
embodiments, for example, this upper liquid level is detected with
a level sensor, as described above.
[0111] The phototrophic biomass-rich first intermediate product 208
is supplied to the decanter 214 to further effect dewatering of the
phototrophic biomass and effect separation from the phototrophic
biomass-rich first intermediate product 208 of a phototrophic
biomass-rich second intermediate product 218 and aqueous product
2181. In some embodiments, for example, the supply of the
phototrophic biomass-rich first intermediate product 208 to the
decanter 214 is modulated based on the detected concentration of
phototrophic biomass within the phototrophic biomass-rich first
intermediate product 208. In such embodiments, the phototrophic
biomass-rich first intermediate product 208 is supplied to the
decanter 214 when the concentration of phototrophic biomass within
the phototrophic biomass-rich first intermediate product 208 is
above a predetermined concentration. In some embodiments, for
example, the supply of the product 208 to the decanter 214 is
controlled by a valve 215 that responds to a signal from a
controller upon the determination of a deviation of the detected
phototrophic biomass concentration within the phototrophic
biomass-rich first intermediate product from a predetermined value.
In some embodiments, for example, the motor speed of the decanter
is controlled by a variable frequency drive, also in response to a
signal from a controller upon the determination of a deviation of
the detected phototrophic biomass concentration within the
phototrophic biomass-rich first intermediate product from a
predetermined value. The decanter 214 effects separation of the
aqueous product 2181 and the phototrophic biomass-rich second
intermediate product 218 from the phototrophic biomass-rich first
intermediate product 214. The aqueous product 2181 is supplied to
the settling column 212. The phototrophic biomass-rich second
intermediate product 218 is discharged from the decanter 214 and
supplied to the dryer 50 which supplies heat to the phototrophic
biomass-rich second intermediate product 218 to effect evaporation
of at least a fraction of the water of the phototrophic
biomass-rich second intermediate product 218, and thereby effect
production of a final phototrophic biomass-comprising product. As
discussed above, in some embodiments, the heat supplied to the
intermediate concentrated phototrophic biomass-comprising product
218 is provided by a heat transfer medium which has been used to
effect the cooling of the supplied exhaust gas prior to supply of
the supplied exhaust gas to the contacting zone. By effecting such
cooling, heat is transferred from the supplied exhaust gas to the
heat transfer medium, thereby raising the temperature of the heat
transfer medium. In such embodiments, the heat requirement to
effect evaporation of water from the phototrophic biomass-rich
second intermediate product is not significant, thereby rendering
it feasible to use the heated heat transfer medium as a source of
heat to effect the drying of the phototrophic biomass-rich second
intermediate product. After heating the phototrophic biomass-rich
second intermediate product, the heat transfer medium, having lost
some energy and becoming disposed at a lower temperature, is
recirculated to the heat exchanger to effect cooling of the
supplied exhaust gas. The heating requirements of the dryer 50 is
based upon the rate of supply of the phototrophic biomass-rich
second intermediate product to the dryer 50. Cooling requirements
(of the heat exchanger) and heating requirements (of the dryer 50)
are adjusted by the controller to balance the two operations by
monitoring flow rates and temperatures of each of the supplied
exhaust gas and the rate of production of the product 202 through
discharging of the product 202 from the photobioreactor 12.
[0112] While this invention has been described with reference to
illustrative embodiments and examples, the description is not
intended to be construed in a limiting sense. Thus, various
modifications of the illustrative embodiments, as well as other
embodiments of the invention, will be apparent to persons skilled
in the art upon reference to this description. It is therefore
contemplated that the appended claims will cover any such
modifications or embodiments. Further, all of the claims are hereby
incorporated by reference into the description of the preferred
embodiments.
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