U.S. patent application number 14/005774 was filed with the patent office on 2014-01-09 for method for the energy-efficient and environmentally friendly obtention of light oil and/or fuels on the basis of crude bitumen from oil shales and/or oil sands.
This patent application is currently assigned to ECOLOOP GMBH. The applicant listed for this patent is Leonhard Baumann, Ulf Boenkendorf, Roland Moller, Thomas Stumpf. Invention is credited to Leonhard Baumann, Ulf Boenkendorf, Roland Moller, Thomas Stumpf.
Application Number | 20140008272 14/005774 |
Document ID | / |
Family ID | 45976891 |
Filed Date | 2014-01-09 |
United States Patent
Application |
20140008272 |
Kind Code |
A1 |
Stumpf; Thomas ; et
al. |
January 9, 2014 |
METHOD FOR THE ENERGY-EFFICIENT AND ENVIRONMENTALLY FRIENDLY
OBTENTION OF LIGHT OIL AND/OR FUELS ON THE BASIS OF CRUDE BITUMEN
FROM OIL SHALES AND/OR OIL SANDS
Abstract
The present invention relates to a method for the
energy-efficient and environmentally friendly obtention of light
oil and/or fuels on the basis of crude bitumen from oil shales
and/or oil sands (1) by thermal use of carbonaceous residues which
are obtained during this process, whereby the carbonaceous residues
are converted at temperatures below 1800.degree. C. into
sulfur-poor, gaseous cleavage products (31) by sub-stoichiometric
oxidation with oxygen-containing gas in an updraft gasifier (19)
which is operated with a bulk material moving bed while alkaline
substances are added. The cleavage products are then converted into
sensible heat by hyperstoichiometric oxidation and are used for the
production of heated aqueous process media (2) for physically
comminuting the oil sands and/or oil shales (1) and/or for
separating of the crude bitumen (7) from the rock material and/or
as process heat for the thermal fractioning (12) of the crude
bitumen (7).
Inventors: |
Stumpf; Thomas; (Bad
Harzburg, DE) ; Boenkendorf; Ulf; (Holle, DE)
; Baumann; Leonhard; (Aldersbach, DE) ; Moller;
Roland; (Bad Harzburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stumpf; Thomas
Boenkendorf; Ulf
Baumann; Leonhard
Moller; Roland |
Bad Harzburg
Holle
Aldersbach
Bad Harzburg |
|
DE
DE
DE
DE |
|
|
Assignee: |
ECOLOOP GMBH
Goslar
DE
|
Family ID: |
45976891 |
Appl. No.: |
14/005774 |
Filed: |
March 16, 2012 |
PCT Filed: |
March 16, 2012 |
PCT NO: |
PCT/EP2012/001168 |
371 Date: |
September 17, 2013 |
Current U.S.
Class: |
208/390 ;
208/347 |
Current CPC
Class: |
C10K 1/024 20130101;
C10G 2300/202 20130101; C10J 2300/0946 20130101; C10G 2300/4081
20130101; C10J 2300/0996 20130101; C10G 1/02 20130101; C10G 1/04
20130101; F23G 2201/40 20130101; C10J 2300/0903 20130101; C10G
2300/1003 20130101; C10J 3/20 20130101; Y02E 60/32 20130101; C10J
2300/0906 20130101; C10J 3/84 20130101; C10J 3/12 20130101 |
Class at
Publication: |
208/390 ;
208/347 |
International
Class: |
C10G 1/04 20060101
C10G001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2011 |
DE |
10 2011 014 345.9 |
Claims
1. A method for energy-efficient, environmentally friendly
extraction of light oil and/or fuels from crude bitumen from oil
shale and/or oil sands by thermal exploitation of carbon-containing
compounds occurring in this extraction, characterized in that the
carbon-containing compounds contain sulfur and by substoichiometric
oxidation with oxygen-containing gas in a countercurrent gasifier
operated with a moving bed of bulk material are converted, with the
addition of alkaline substances, at temperatures <1800.degree.
C. into low-sulfur gaseous cleavage products, and these cleavage
products are then converted by superstoichiometric oxidation into
perceptible heat, and are used for generating heated aqueous
process media for a physical comminution of the oil sands and/or
oil shale and/or for separating the crude bitumen out of the rock
mass and/or as process heat for a thermal fractionation of the
crude bitumen.
2. The method of claim 1, characterized in that as
carbon-containing compounds, solid residues from the aqueous
separation of crude bitumen from the rock mass and/or solid
residues from the thermal fractionation of the crude bitumen are
used.
3. The method of claim 1, characterized in that the countercurrent
gasifier is embodied as a vertical process chamber with a
calcination zone and an oxidation zone, in which the calcined
carbon- and sulfur-containing residues oxidize with
oxygen-containing gas, and the gaseous reaction products are drawn
off at the top of the vertical reaction chamber, the vertical
process chamber being in the form of a vertical shaft furnace,
through which a bulk material that itself is not oxidized flows
continuously from top to bottom, and the oxygen-containing gas is
introduced at least partially below the oxidation zone, thereby
further advancing the rising gas stream.
4. The method of claim 1, characterized in that as alkaline
substances, metal oxides, metal carbonates, metal hydroxides or
mixtures of two or three of these substances are used, and are
metered purposefully into the vertical process chamber and/or into
the gas phase above the calcination zone, and/or are admixed with
the carbon-containing compounds before entering the vertical
process chamber.
5. The method of claim 4, characterized in that the metal oxides,
metal carbonates, and metal hydroxides contain elements of the
alkali metals or elements of the alkaline earth metals and
especially preferably contain calcium as a cation.
6. The method of claim 1, characterized in that the alkaline
substances are used at least partially in fine-granular form with a
particle size of less than 2 mm.
7. The method of claim 1, characterized in that the
substoichiometric oxidation is performed at a lambda of less than
0.5 and especially preferably of less than 0.3.
8. The method of claim 1, characterized in that by addition of
alkaline substances under reductive conditions, the gaseous sulfur
compounds occurring in the countercurrent gasifier are converted at
temperatures of above 400.degree. C. from the ingredients of the
carbon- and sulfur-containing residues by chemical reaction with
the alkaline substances into solid sulfur compounds, and these
solid sulfur compounds are at least partially carried out with the
gaseous reaction products, and are removed from the gas phase by
fine-material separation at temperatures above 300.degree. C.
9. The method of claim 1, characterized in that in the vertical
process chamber and/or in the gas phase of the drawn-off gaseous
reaction products in the presence of water vapor and calcium oxide
and/or calcium carbonate and/or calcium hydroxide, a
calcium-catalyzed reformation of substantial proportions is
performed, at temperatures of above 400.degree. C., of the
resultant cleavage products, containing oil and/or tar, that have a
chain length of greater than C4, into carbon monoxide, carbon
dioxide, and hydrogen.
10. The method of claim 1, characterized in that the moving bed of
bulk material is formed partially by additional metering of coarse
material, in order to increase the flowability of the bulk material
and/or its gas permeability, and the coarse material is admixed
with the carbon-containing compounds before entering the vertical
process chamber.
11. The method of claim 10, characterized in that as the coarse
material, mineral substances and/or other inorganic substances or
mixtures of substances, having a particle size in the range of from
2 mm to 300 mm, and especially preferably oil sands and/or oil
shale, are used.
12. The method of claim 10, characterized in that as the coarse
material, wood and/or other biogenic materials having a particle
size in the range of from 2 mm to 300 mm are used.
13. The method of claim 10, characterized in that the coarse
material at the lower end of the vertical process chamber is
separated from the fine material and ashes obtained and is at least
partially returned to the process again as oversized material .
14. The method of claim 1, characterized in that the
carbon-containing compounds, before being used in the
countercurrent gasifier, are converted by agglomeration into
particles having a particle size in the range between 2 mm and 300
mm.
15. The method of claim 1, characterized in that in the vertical
process chamber, between the top and the bottom, a differential
pressure in a range of from 50 to 100 mbar is developed.
Description
[0001] The present invention relates to a method for
energy-efficient, environmentally friendly extraction of light oil
and/or fuels from crude bitumen from oil shale and/or oil sands (A)
by thermal exploitation of carbon-containing compounds (E)
occurring in this extraction.
[0002] Because of the strong worldwide demand for fossil fuels and
petroleum-based raw materials, as well as the expected long-term
scarcity of conventional petroleum, the recovery of energy carriers
and raw materials from oil shale and/or oil sand resources is
becoming increasingly important.
[0003] Naturally occurring oil sands or oil shale comprise natural
rock and contain up to 20% of a bitumen mixture. This bitumen
mixture essentially contains organic carbon compounds with
different molecular weights and boiling points.
BACKGROUND OF THE INVENTION
[0004] To make these carbon compounds accessible to purposeful
extraction, the bitumen mixture must first be separated from the
natural rock component.
[0005] The separation of the bitumen from these natural rock masses
can be done essentially via two technologies.
[0006] Quarrying by open pit mining:
[0007] In this method, the rock mass containing bitumen is carried
away using overburden dredgers or wheel loaders and transported to
the processing plants with heavy road vehicles. The processing is
done as a rule in the following process steps:
[0008] 1. Breaking up/comminuting the rock, as a rule while
supplying water vapor or hot water
[0009] 2. Sending the resultant suspension to the first extraction
step, where sediment and water form as the lower separation layer,
and bitumen with foam forms as the upper separation layer.
[0010] 3. Carrying away the lower sediment and water layer to
usually artificial lakes or water lagoons.
[0011] 4. Carrying away the upper bitumen layer to the second
extraction step, where residues of water and fine particles are
separated out. The bitumen is usually dissolved in an organic
solvent (as a rule, "naphtha", which is a product of the light-oil
recovery process). What is obtained is so-called crude bitumen.
[0012] 5. The crude bitumen is sent to ensuing bitumen processing
("upgrading").
[0013] Recovery by the so-called "in-situ method":
[0014] In this technology, the crude bitumen is already recovered
in the soil, below the surface and without breaking up the rock
masses. This is accomplished as follows:
[0015] 6. High-pressure water vapor is injected into deep
bitumen-containing rock strata. As a result, a thermal liquefaction
of the crude bitumen is achieved.
[0016] 7. This liquefied crude bitumen is carried purposefully into
underground collection points and pumped from there to the surface,
by means of suitable pumping technology.
[0017] 8. The crude bitumen thus recovered then, as a rule, follows
the same further procedure as in step 5 above.
[0018] Extraction of light oil and liquid fuels from crude
bitumen:
[0019] The crude bitumen (possibly from both recovery methods) is
combined in the next processing plant ("upgrading"). There, the
following process steps are usually performed:
[0020] 9. From the mixture comprising crude bitumen and naphtha,
the volatile hydrocarbons are distilled off. At the end, what
remains is an insoluble residue, called pet coke. Depending on the
material used, it can contain up to 10% sulfur components.
[0021] 10. The gaseous hydrocarbons from the distillation are
separated by fractionated condensation into naphtha, kerosene, and
gas oil; naphtha is as a rule at least partially returned to the
process
[0022] 11. Depending on the quality required of the individual
fractions, desulfurization can be done in the further step. This is
usually done by means of hydrogenation and separating out of the
elemental sulfur.
[0023] 12. At the end of the process come the storage and shipping
out of the liquid fractions.
[0024] However, the method described above for recovering light oil
and fuels from oil shale and/or oil sands has considerable
disadvantages.
[0025] For instance, extracting the crude bitumen from the rock
masses requires considerable amounts of hot water and water vapor.
Per volumetric unit of light oil, up to 6 volumetric units of water
have to be used. The preparation of steam and hot water is usually
done in boilers fired by natural gas. The demand for natural gas is
extremely high and leads to an extraordinarily unfavorable energy
balance of the entire process. Moreover, as a result the specific
CO.sub.2 emissions per barrel of light oil obtained is
fundamentally unacceptable ecologically and in view of the need to
use valuable resources sparingly.
[0026] The pet coke remaining behind in the distillation of the
crude bitumen (step 9) contains sulfur in concentrations of up to
10%. This is fundamentally a valuable energy carrier. However,
because of its high sulfur content, it cannot readily be used in
combustion processes, such as for generating water vapor or hot
water. Ensuring environmentally sound thermal exploitation is
therefore questionable and is possible, if at all, only at
disproportionate expense for flue gas desulfurization.
[0027] For the present invention, the object has therefore arisen
of furnishing a method which does not have the disadvantages of the
prior art but permits energy-efficient exploitation of carbon
carriers contained in oil sands and/or oil shale, which handles
fossil fuels (such as natural gas) sparingly, and which on its own
can generate sufficient energy carriers to supply the requisite
energy demand for the exploitation process, at least in part.
[0028] This is attained according to the invention in that the
carbon-containing compounds contain sulfur and by substoichiometric
oxidation with oxygen-containing gas in a countercurrent gasifier
operated with a moving bed of bulk material are converted, with the
addition of alkaline substances, at temperatures <1800.degree.
C. into low-sulfur gaseous cleavage products, and these cleavage
products are then converted by superstoichiometric oxidation into
perceptible heat, and are used for generating heated aqueous
process media for a physical comminution of the oil sands and/or
oil shale and/or for separating the crude bitumen out of the rock
mass and/or as process heat for a thermal fractionation of the
crude bitumen.
[0029] It has been demonstrated that the residues that were not
heretofore exploited because of the problems with sulfur are
capable of improving the energy balance in the recovery of light
oil and/or fuels from oil shale and/or oil sands considerably. By
the appropriate exploitation of the carbon ingredients, the threat
to the environment from carbon compounds that until now remained in
the residues is overcome as well.
[0030] For example, as carbon-containing compounds, solid residues
from the aqueous separation of crude bitumen from the rock mass
and/or solid residues from the thermal fractional distillation of
the crude bitumen can be used.
[0031] A refinement of the method is especially advantageous in
which the countercurrent gasifier is embodied as a vertical process
chamber with a calcination zone and an oxidation zone, in which the
calcined carbon- and sulfur-containing residues oxidize with
oxygen-containing gas, and the gaseous reaction products are drawn
off at the top of the vertical reaction chamber, in the form of a
vertical shaft furnace, through which a bulk material that itself
is not oxidized flows continuously from top to bottom, and the
oxygen-containing gas is introduced at least partially below the
oxidation zone, thereby further advancing the rising gas stream.
The advantage of an inert bulk material is that the mechanical
properties of the pile can be more easily varied and adapted to the
essential aspects of the method.
[0032] Examples of as alkaline substances that can be used are
metal oxides, metal carbonates, metal hydroxides or mixtures
thereof, which are metered into the gas phase above the calcination
zone and/or are admixed with the carbon-containing compounds before
entering the vertical process chamber. Elements of the alkali
metals or elements of the alkaline earth metals, especially
calcium, are preferred for forming the metal oxides, carbonates of
hydroxides, since particularly in the form of calcium oxide,
catalytic effects have a favorable effect on the courses of the
method.
[0033] Adding the alkaline substances at least partially in
fine-granular form, with a particle size of <2 mm, has proved
advantageous, as has a substoichiometric oxidation at a .lamda. of
<0.5, especially preferably <0.3.
[0034] The sulfur-binding mechanisms proceed especially
advantageously by addition of alkaline substances under reductive
conditions, in which the gaseous sulfur compounds occurring in the
countercurrent gasifier at temperatures of above 400.degree. C.
from the ingredients of the carbon-and sulfur-containing residues
are converted by chemical reaction with the alkaline substances
into solid sulfur compounds, and these solid sulfur compounds are
at least partially carried out with the gaseous reaction products,
and are removed from the gas phase by fine-material separation at
temperatures above 300.degree. C. In this way, the sulfur can be
removed from the process especially economically.
[0035] In a desired course of the method, in the vertical process
chamber and/or in the gas phase of the drawn-off gaseous reaction
products in the presence of water vapor and calcium oxide and/or
calcium carbonate and/or calcium hydroxide, a calcium-catalyzed
reformation of substantial proportions is performed, at
temperatures of above 400.degree. C., of the resultant cleavage
products, containing oil and/or tar, that have a chain length of
greater than C4, into carbon monoxide, carbon dioxide, and
hydrogen.
[0036] The moving bed of bulk material is preferably formed by
additional metering of coarse material, in order to increase the
flowability of the bulk material and/or its gas permeability, and
the coarse material is admixed with the carbon-containing compounds
before entering the vertical process chamber. As the coarse
material, mineral substances and/or other inorganic substances,
such as mixtures of substances, having a particle size in the range
of from 2 mm to 300 mm, and especially preferably oil sand and/or
oil shale, can be used. The latter case is especially preferred,
since as a result, a method course in which resources occurring on
site can be used and exploited directly is made possible.
[0037] Using wood and/or other biogenic materials as coarse
material, with a suitable particle size, can also be advantageous.
Often, these materials are available in the vicinity of the site
where the method is performed, so given the short transportation
distances, their use is favorable for the sake of overall energy
efficiency.
[0038] Inert bulk material can be separated off at the lower end of
the vertical process chamber from the fine material and ashes
produced and can be returned at least partially to the process as
coarse material, so that the distances the masses have to be moved
can be kept short. It can also be advantageous to convert the
carbon-containing compounds before their use in the countercurrent
gasifier by agglomeration into particles with a particle size in
the range between 2 mm and 300 mm, in order to improve the
flowability of the bulk material and/or its gas permeability, as is
done with the additional metering in of coarse material.
[0039] For the gas countercurrent, the development of a
differential pressure in a range of from 50 to 100 mbar (u) in the
vertical process chamber, between the top and the bottom, has
proved advantageous.
[0040] FIG. 1 shows one example of an integrated method for
producing light oil and fuels by breaking down the oil sands and
oil shale in open pit mining.
[0041] The oil sands and oil shale (A) quarried by open pit mining
are mechanically comminuted via breaker systems (1). This is
usually done by mixing in hot water or also water vapor (2). Hot
water/water vapor is produced in boiler systems (3).
[0042] The suspension resulting from the mechanical comminution is
delivered to a first extraction stage (4). Here, as a rule, hot
water/water vapor is added again. After intensive mixing, in the
extraction stage (4) a separation of the phases is performed by
settling. A water/sediment phase (B) forms as the lower phase. It
is separated off and usually deposited in artificial lagoons or
lakes (6).
[0043] The upper phase (7) essentially contains crude bitumen. It
is separated off and delivered to the next process step (C).
[0044] In the first extraction stage, a middle phase (8) forms as a
rule; besides water/sediment, it can also contain significant
amounts of crude bitumen. This middle phase can be delivered to a
second extraction stage (9). Here, a second separation is
performed, in which the lower water/sediment phase (D) is separated
off and likewise deposited in artificial lagoons or lakes (6). The
upper phase (10) essentially contains crude bitumen and is likewise
delivered to the next process stage (C).
[0045] In process step (C), the crude bitumen can be mixed with
organic solvents, such as naphtha (11), which is obtained as a
product in the later bitumen refining process. Depending on the
quality of the bitumen, undissolved residues (E), also called pet
coke, can occur here.
[0046] The dissolved crude bitumen is delivered to a distillation
stage (12), where the volatile ingredients are evaporated off by
adding heat by means of hot steam (13) from the boiler systems and
using suitable distillation equipment; additional pet coke (E)
remains behind, as a nonvolatile ingredient. This pet coke
comprises carbon-rich residues, which have a high thermal value but
can contain up to 10% sulfur.
[0047] The volatile ingredients (14) are separated, for instance
via fractionated condensation (15), into various boiling fractions,
which can comprise light oil (16), naphtha (11), and various fuels
(17), among other things.
[0048] The method described is very energy-intensive, since very
large quantities of hot water/water vapor have to be produced in
boiler systems (3). Until now, considerable quantities of fossil
fuels, especially natural gas (18), have been used for the
purpose.
[0049] The method of the invention provides for replacing this
natural gas entirely or in part with synthesis gas (20) generated
in the countercurrent gasifier (19), and using this synthesis gas
as fuel in the boiler systems.
[0050] The production of the synthesis gas is done by gasification
of carbon-containing materials in a countercurrent gasifier (19),
which is embodied as a vertical process chamber. A bulk material
(21) flows through this process chamber from top to bottom. The
bulk material can preferably comprise material of a coarse particle
size, and as the bulk material, it is also suitable to use sediment
(B) and/or (D). Especially advantageously, the bulk material can
also be formed partially by the oil sand/oil shale (A); in this
case, it can also be advantageous for the material, before being
used as bulk material, to be comminuted mechanically to a particle
size of less than 20 cm. Further residues from the method described
above can be added to this bulk material before it enters the
countercurrent gasifier. For that purpose, the pet coke (E), which
because of its high carbon content has a high thermal value, is
particularly well suited. The mixture of bulk material and residues
flows through the vertical process chamber (19) by gravity from top
to bottom. The countercurrent gasifier has burner lances (22) in
its middle region, which ensure constant- load firing in the
vertical process chamber and the stationary development of a
burning zone (23). These burner lances can be fueled by fossil
fuels (24) and oxygen-containing gas (25). Alternatively to the
fossil fuels, synthesis gas from the countercurrent gasifier (20),
or the crude bitumen (C) dissolved in naphtha, can also be
used.
[0051] At the lower end of the vertical process chamber,
oxygen-containing gas (26) is introduced. This gas serves first to
cool down the bulk material before in a cooling zone (27) before it
leaves the vertical process chamber. The oxygen-containing gas is
thus preheated as it continues to flow upward in the vertical
process chamber. On the countercurrent gasification principle, the
oxygen from the oxygen-containing gas reacts with the
carbon-containing materials in the bulk material by oxidation, and
the quantity of oxygen-containing gas is adjusted such that a total
lambda of less that 0.5 is established in the vertical process
chamber. As a result, first a burning zone (23) is formed, in which
residues of the carbon-containing material react with oxygen to
form CO.sub.2. Farther upward, the oxygen decreases further, so
that finally, only low-temperature carbonization can occur, until
still farther upward, all the oxygen is finally consumed, and a
pyrolysis zone (28) forms,
[0052] Conversely, if one looks at the flow of the bulk material
and the carbon-containing materials from top to bottom, what
happens first in the pyrolysis zone (28) is drying of the typically
moist materials used, until an intrinsic temperature of 100.degree.
C. is reached. After that, the intrinsic temperature of the
materials rises further, causing the gasification process to begin,
and at an intrinsic temperature of up to 500.degree. C., the
formation of methane, hydrogen and CO begins. After extensive
degassing, the intrinsic temperature of the materials that are
moving downward increases further because of the hot gases rising
from the burning zone (23), so that finally, the carbon-containing
materials are entirely degassed and now comprise nothing but
residual coke, so-called pyrolysis coke, and ash components. The
pyrolysis coke is transported with the bulk material farther
downward in the vertical process chamber, where it is converted
partly into CO at temperatures above 800.degree. C. with the
CO.sub.2 components from the burning zone by Boudouard conversion
and likewise gasified. Some of the pyrolysis coke also reacts in
this zone by the water-gas reaction with water vapor, which is
likewise present in the hot gases, forming CO and hydrogen.
Finally, at temperatures below 1800.degree. C., residues of the
pyrolysis coke are practically completely combusted and thermally
utilized in the burning zone (23) along with the oxygen-containing
gas flowing in from below. As a result, it is possible for the
countercurrent gasifier to be supplied with virtually all the
energy needed for the gasification. This is also known as an
autothermal gasification process.
[0053] Water (29), as an additional cooling and gasification
medium, can also be metered into the cooling zone via water lances
(30).
[0054] The synthesis gas formed in the vertical process chamber is
extracted at the upper end by suction (31), so that in the upper
gas chamber (32), a slight underpressure of from 0 to 200 mbar is
established.
[0055] Depending on the quality of the substances used,
considerably amounts of gaseous sulfur compounds can occur during
the gasification process. It is therefore advantageous if alkaline
substances (33) are admixed with the bulk material before it enters
the vertical process chamber. For this purpose, metal oxides, metal
hydroxides, or metal carbonates are especially suitable, and the
use of fine-granular calcium oxide is especially preferred, since
because of its reactivity and large surface area it reacts
spontaneously with the gaseous sulfur compounds formed and thereby
forms solid sulfur compounds, which are quite predominantly removed
from the vertical process chamber together with the synthesis gas
that is extracted by suction. Still other contaminants, such as
chlorine, hydrogen chloride, or even heavy metals, can be bound
highly effectively to the CaO and removed from the process in the
same way.
[0056] Additionally, it can be appropriate to use coarse-granular
metal oxides, metal hydroxides or metal carbonates as bulk
material, in order on the one hand to increase the proportion of
bulk material to the carbon-containing materials and on the other
also to make alkaline reaction partners available in the lower part
of the vertical process chamber for binding the gaseous sulfur
compounds.
[0057] The synthesis gas extracted by suction contains dust, which
essentially comprises the solid sulfur compounds, fine-granular
alkaline substances, other contaminants, and inert particles. This
synthesis gas containing dust can be treated in the gas chamber of
the vertical process chamber, or after leaving the vertical process
chamber, in the presence of water vapor and fine-granular calcium
oxide at temperatures of over 400.degree. C. This temperature can
be established by suitable adjustment of the quantity of
oxygen-containing gas (26) at the lower end of the vertical process
chamber or by means of the calorific output of the burner lances
(22) in the burning zone. However, it is especially advantageous to
use direct fining in the synthesis gas via burner lances (34),
which are operated stoichiometrically with fuel and
oxygen-containing gas or even with an excess of oxygen-containing
gas. This thermal posttreatment in the presence of water vapor and
calcium oxide ensures that the oils and tars still present in the
synthesis gas will be split off by the catalytic action of the
calcium oxide.
[0058] The dust-containing synthesis gas is then freed of dust at
temperatures above 300.degree. C. by way of hot-gas filtration
(35). The filter dust (36) containing sulfur is spun out of the
process and either disposed of or put to an alternative use.
[0059] The resultant synthesis gas is practically sulfur-fee and
can be used as fuel in the boiler systems (3). Depending on
conditions on site or on the requirements of the boiler systems, it
may be necessary to cool down the synthesis gas using gas coolers
(38) and to free it of condensates, before it can be used in the
boiler systems.
[0060] The condensate (39) that occurs can be used again at least
partially as a cooling and gasification medium via the water lances
(30) in the vertical process chamber.
[0061] The combustion of the cleaned synthesis gas (20) permits the
boiler systems to be operated without requiring that the flue gas
(40) be treated by means of complicated flue gas
desulfurization.
[0062] The bulk material mixture (41) emerging from the lower end
of the vertical process chamber essentially contains
coarse-particle bulk material, ash residues, and fine-granular bulk
material. The fine-granular bulk material may still contain slight
amounts of sulfur products and other contaminants.
[0063] The entire bulk material stream can be stored (42) in its
entirety. However, it is especially preferable to screen the bulk
material mixture (43), with the coarse fraction (44) preferably put
at least partially into circulation and used again as bulk material
in the vertical process chamber.
[0064] The fine screened fraction (45), together with the filter
dust (36) that contains sulfur, is spun out of the process and
disposed of or put to an alternative use.
[0065] FIG. 2 shows an example of an integrated method for
extracting light oils and fuels, in which the crude bitumen is
quarried by the subsurface in-situ method.
[0066] In the in-situ method, the crude bitumen is not obtained by
breaking down the soil and extracting it; instead, it is liquefied
by melting in the earth's crust and brought to the surface via
pumping systems.
[0067] In this process, high-pressure steam from the boiler system
(3) is injected into bituminous soil (1) by means of special lance
systems (2). As a result, the bitumen is liquefied (4) and diverted
to underground collection points (5). From there, the liquid crude
bitumen is brought to the surface via ascending pipelines (6) and
special conveyor systems (7). This liquid crude bitumen is then
used in the next process stage C.
[0068] A further technology contemplates the use of special burner
lances (8), by way of which partial combustion of the crude bitumen
in the earth's crust is initiated. This can be done for instance by
superstoichiometric combustion of fossil fuels (9) with
oxygen-containing gas (10), as a result of which the excess
oxygen-containing gas (10) effects a partial combustion of the
crude bitumen in the soil and thereby furnishes energy for the
liquefaction of the crude bitumen.
[0069] According to the invention, it is also possible in this
example to produce the required high-pressure steam in the boiler
systems (3) using synthesis gas (20) as fuel. Synthesis gas can
also be used as fuel for the partial combustion via the special
burner systems (8).
[0070] Often, the in-situ method is also combined with the open-pit
mining of FIG. 1. In both cases, crude bitumen is extracted, which
is then combined in process stage (3) and further refined.
[0071] The further course of the process after process stage (C) is
analogous to the description of FIG. 1.
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