U.S. patent application number 12/080313 was filed with the patent office on 2008-10-23 for smokeless furnace.
Invention is credited to E. Laurence Green.
Application Number | 20080257236 12/080313 |
Document ID | / |
Family ID | 39870956 |
Filed Date | 2008-10-23 |
United States Patent
Application |
20080257236 |
Kind Code |
A1 |
Green; E. Laurence |
October 23, 2008 |
Smokeless furnace
Abstract
A biomass fired boiler having a series of inverted U-shaped
exhaust gas flues. Water from a collection tank is pumped and
sprayed onto deflection plates in the towers. The exhaust gases
progressively commingle with the droplets to extract heat energy
and collect contaminants at the tank until all the smoke has been
absorbed into the water. The heated water is re-directed through a
thermal exchanger of the heat transfer system and heat energy is
reclaimed. Floating and/or suspended contaminants are filtered
and/or collected and appropriately removed and/or incinerated.
Inventors: |
Green; E. Laurence;
(Gildford, MT) |
Correspondence
Address: |
DOUGLAS L. TSCHIDA
633 LARPENTEUR AVE. WEST, SUITE B
ST. PAUL
MN
55113
US
|
Family ID: |
39870956 |
Appl. No.: |
12/080313 |
Filed: |
April 2, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60923823 |
Apr 17, 2007 |
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Current U.S.
Class: |
110/215 |
Current CPC
Class: |
F23J 2217/20 20130101;
F24D 2200/18 20130101; F23B 80/04 20130101; F23J 15/04 20130101;
B01D 53/78 20130101; F23J 2219/70 20130101; F24D 2200/065 20130101;
F23J 2217/60 20130101; Y02B 10/70 20130101; F23J 15/003
20130101 |
Class at
Publication: |
110/215 |
International
Class: |
F23J 15/00 20060101
F23J015/00 |
Claims
1. A heating system comprising: a) a combustible fuel fired furnace
including liquid thermal transfer means for extracting heat from
combusted materials and transferring the heat to a circulated
liquid and exhaust means for exhausting combustion gases; and b)
exhaust treatment means for receiving exhausted combustion gases
and conveying the gases through a liquid rich atmosphere to extract
exhausted heat and contaminants in the gases and vent substantially
only moist vapor to the environment.
2. A system as set forth in claim 1 wherein said exhaust treatment
means includes a hollow tower coupled to receive said combustion
gases and coupled to a lower lying collection container containing
a wash liquid, wherein the wash liquid is directed into the tower
to commingle with the combustion gases under the influence of
gravity to heat the liquid and extract solids from the gases, and
wherein the liquid is coupled to said liquid thermal transfer
means.
3. A system as set forth in claim 2 wherein said furnace includes
an exhaust flue, wherein said exhaust treatment means comprises a
cylindrical, inverted U-shaped tower coupled to said exhaust flue
to receiving said exhausted combustion gases, wherein said tower
includes a baffle and onto which a stream of wash liquid is
directed, and wherein said baffle converts the liquid to form
droplets and mist.
4. A system as set forth in claim 3 including a second cylindrical
inverted U-shaped tower, wherein at least the input ends of the
first and second towers project from a cover mounted to said
collection container, wherein the level of wash liquid in the
collection container is maintained to provide a space between the
cover and liquid whereby the exhaust gases can flow from an output
of the first tower to an input of the second tower.
5. A system as set forth in claim 4 including means for filtering
the wash liquid of suspended particulates and contaminants.
6. A system as set forth in claim 4 including means having a
plurality of paddles mounted to rotate to skim materials floating
on the wash liquid, collect and incinerate the skimmed flotsam.
7. A system as set forth in claim 4 wherein said collection
container includes thermal exchanger means for directing the wash
liquid over the thermal exchanger means to extracting heat
reclaimed in the wash liquid and re-circulate the reclaimed heat
via a media passed through the thermal exchanger means.
8. A system as set forth in claim 4 including means for circulating
a supply of air over the space between the cover and liquid to
moisturize the air and convey the air to the heated premises.
9. A system as set forth in claim 2 wherein said wash liquid
comprises a mixture of water, soda and a sudsing ingredient.
10. A heating system comprising: a) a combustible fuel fired
furnace including liquid thermal transfer means for extracting heat
from combusted materials and transferring the heat to a circulated
liquid and an exhaust flue for exhausting combustion gases; and b)
first and second hollow towers projecting from a cover mounted to
over lie a collection container containing a wash liquid, wherein
at least one of said first and second towers is coupled to said
exhaust flue and including means for conveying the exhaust gases
through said first and second towers, wherein the wash liquid is
directed into the first and second towers to commingle with the
combustion gases under the influence of gravity to heat the liquid
and extract solids from the gases and vent substantially only moist
vapor to the environment, and wherein the liquid is coupled to said
liquid thermal transfer means
11. A system as set forth in claim 10 wherein said furnace includes
an exhaust flue, wherein said exhaust treatment means comprises a
cylindrical, inverted U-shaped tower coupled to said exhaust flue
to receiving said exhausted combustion gases, wherein said tower
includes a baffle and onto which a stream of wash liquid is
directed, and wherein said baffle converts the liquid to form
droplets and mist.
12. A system as set forth in claim 10 wherein said first and second
towers comprise cylindrical inverted U-shaped conduits, wherein at
least an input end of each of the first and second towers project
from said cover mounted to said collection container, wherein the
level of wash liquid in the collection container is maintained to
provide a space between the cover and liquid whereby the exhaust
gases can flow from an output of the first tower to an input of the
second tower.
13. A system as set forth in claim 10 including means for filtering
the wash liquid of suspended particulates and contaminants.
14. A system as set forth in claim 10 including means having a
plurality of paddles mounted to rotate to skim materials floating
on the wash liquid, collect and incinerate the skimmed flotsam.
15. A system as set forth in claim 10 wherein said collection
container includes thermal exchanger means for directing the wash
liquid over the thermal exchanger means to extracting heat
reclaimed in the wash liquid and re-circulate the reclaimed heat
via a media passed through the thermal exchanger means.
16. A system as set forth in claim 10 including means for
circulating a supply of air over the space between the cover and
liquid to moisturize the air and convey the air to the heated
premises.
17. A system as set forth in claim 10 wherein said wash liquid
comprises a mixture of water, soda and a sudsing ingredient.
Description
RELATED APPLICATION DATA
[0001] This is a non-provisional application of provisional
application Ser. No. 60/923,823, filed Apr. 17, 2008.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to biomass fired boilers and,
in particular, to a high-efficiency boiler that can be fired with a
variety of alternative combustible fuels (e.g. wood, coal, waste,
byproducts, pellets, corn, petroleum waste, gas, oil or other
organic material) and wherein the exhaust gases are conducted
through a shower system to absorb the exhaust gases (i.e. smoke),
reclaim the exhausted heat and clean contaminants from the gaseous
effluent.
[0003] The present invention was developed to provide a heating
system wherein exhaust gases from a boiler/stove/furnace are passed
through a moist environment created by a shower system to absorb
the exhaust gases (i.e. smoke), reclaim the exhausted heat and
clean carbon dioxide and other contaminants from the gaseous
effluent. The shower system comprises a serpentine series of
gravity towers (e.g. inverted U-shaped) that channel the exhaust
gases; expose the gases to a moisture rich environment (e.g. water
droplets and mist); and collect the heated water in a collection
tank. The exhaust gases are passed through a humid environment of
patterned water droplets and mist that is formed in the towers to
absorb the exhaust gases, heat energy and contaminants. The heated
water is gravity collected at the collection tank and successively
reduced concentrations of exhaust gases are passed to each
successive tower. A portion of the heated water is re-circulated
through the towers. The remainder of the heated water is filtered,
cleaned of effluents and circulated through the liquid heat
transfer system associated with the boiler/stove/furnace and/or a
secondary thermal transfer system. Solid effluents and contaminants
are skimmed, filtered and/or collected, incinerated or otherwise
disposed.
SUMMARY OF THE INVENTION
[0004] It is a primary object of the invention to provide a high
efficiency fuel fired heating system.
[0005] It is further object of the invention to provide a boiler
system wherein exhaust gases are conveyed through a shower system
comprised of a serpentine series of conduits (e.g. towers) fed with
gravity water showers.
[0006] It is further object of the invention to provide a series of
inverted U-shaped towers that communicate with a liquid (e.g.
water) supply and collection tank.
[0007] It is further object of the invention to provide a system
wherein each inverted U-shaped tower includes a spray forming
assembly such as a deflector to form droplets and mist that absorb
and cleanse the exhaust gases.
[0008] It is further object of the invention to provide a closed
system wherein pumps, valves, filters, skimmers, sensors and
electro-mechanical servos operate to control and direct water flow
from the collection tank to the spray towers and thermal transfer
assembly(s); monitor water temperature, water level and collected
effluent and contaminants; and channel the gases through each tower
until the gases are fully absorbed and solid effluents and
contaminants are collected, burned or otherwise disposed.
[0009] The foregoing objects, advantages and distinctions of the
invention are obtained in one construction of a biomass fired
boiler and associated liquid heat exchange system. Combustion
exhaust gases or smoke formed in the burn chamber(s) of the boiler
are coupled via a primary flue to a closed system defined by a
sequential series of inverted U-shaped towers disposed above a
water collection tank. Water from the collection tank is pumped and
sprayed onto deflection plates in the towers. The exhaust gases
commingle with the droplets and mist to heat the water and extract
heat energy, effluents and contaminants contained in the smoke.
[0010] Residual gases are successively channeled from the
collection the tank to each tower until fully washed and only vapor
remains. A portion of the heated water is re-circulated through the
towers. The remainder of the heated water is filtered and
circulated through the heat exchanger and thermal transfer system
coupled to the boiler and heat energy is reclaimed. Floating and/or
suspended contaminants are filtered, skimmed and/or collected and
appropriately removed and/or incinerated. Thermal transfer coils
may also be included to extract heat at the collection tank.
[0011] In an alternative system construction, the exhaust gases
might be conducted through the water at the collection tank (e.g.
in the fashion of bubbling) prior to being conducted to the next
adjacent tower.
[0012] Still other objects, advantages, distinctions, constructions
and combinations of individual features of the invention will
become more apparent from the following description with respect to
the appended drawings. Similar components and assemblies are
referred to in the various drawings with similar alphanumeric
reference characters. The description to each combination should
therefore not be literally construed in limitation of the
invention. Rather, the invention should be interpreted within the
broad scope of the further appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 shows a system block diagram to the construction of
the smokeless furnace or heat transfer system and wherein the spray
towers are shown in partial cutaway to expose internal
assemblies.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] With attention to FIG. 1, a system diagram is shown to the
present novel and inventive heating system 2. The system 2 includes
a boiler/furnace 4 that can be fired with a variety of combustible
fuels (e.g. wood, coal, oil, gas, byproducts and other
organic/biomass materials). The fuel is burned in an associated
burn chamber(s) and heat energy is released and absorbed into a
liquid heat transfer media (e.g. water, water/glycol mixture etc.)
circulated through an associated closed loop, heat exchanger system
4. The heat exchanger 4 is located in close thermal transfer
proximity to the burn chamber(s) and most typically surrounds all
or a portion of the burn chamber(s). The combustion heat is
transferred to the liquid media and the media is circulated from
the internal or external heat exchanger 4 to a conduit/radiator
system 5 that directs the liquid about the heated premises.
[0015] The heat exchanger 4 can include internal exhaust conduits
(not shown) that channel the smoke within or about the burn chamber
to an associated chimney or flue 6. The conduits can be located in
the burn chamber or in the heat exchanger 4 but are positioned such
that the liquid thermal transfer media is in thermal contact with
the conduits to most efficiently extract heat contained in the
exhaust gases.
[0016] Whereas conventional boilers release a portion of the heat
energy to the environment with the smoke or exhaust gases, the
present improved heating system 2 directs substantially no smoke or
exhaust gases to the environment. Essentially all the exhaust gases
and any heat energy in the exhaust gases is captured and any
contaminants contained in the effluents are collected and safely
processed to prevent a negative impact on the environment.
[0017] The exhaust gases are particularly exposed to a liquid
shower or wash system 8 where the exhaust gases are absorbed into a
liquid media and the heat is reclaimed and any contaminants are
collected. The reclaimed heat trapped in the spray water is
combined and re-circulated with the liquid media of the thermal
transfer exchanger 4.
[0018] Turning attention to the upper regions of the boiler 2,
exhaust gases are conducted from the flue 6 to the shower system or
washing assembly 8. The gases can enter the flue 6 at temperatures
approaching 900.degree. F. The assembly 8 provides a number towers
10 of appropriate length, height, and cross-sectional shape and
diameter to treat the exhaust gases until completely absorbed. Two
inverted U-shaped, cylindrical towers 10 are presently provided.
The towers 10 project from a cover or canopy assembly 12 of a lower
lying liquid holding tank 14. More or less towers 10 can be adapted
to accommodate any particular system. The towers 10 can be
constructed to a variety of shapes and orientations, although a
gravity supported construction for reclamation of the water is
preferred.
[0019] A supply of liquid 16 (e.g. water) is contained in the tank
14 to a level that permits the exhaust gases to flow above the
water 16 from one tower 10 to the next. The towers 10 can be
constructed to alternative shapes and can be arranged as desired to
appropriately direct the liquid 16 and gases into the tank 12 and
between the towers 10. The exhaust gases are conducted between and
through the towers 10 due to normal thermal and pressure
differentials and/or provided baffles (not shown) and/or fans (not
shown) fitted to the towers 10 or tank 12.
[0020] The water or other appropriate liquid 16 stored in the tank
14 is directed via one or more pumps 18 and a conduit system 20
into the towers 10. Valves 22 located along the piping of the
conduit system 20 control the flow of liquid into the towers
10.
[0021] A portion of the liquid 16 is sprayed to impinge or strike
baffles 24 fitted inside the towers 10. The baffles 24 break up
liquid spray into droplets and mist that fall back through the
towers 10 to the tank 14. The baffles 24 can be positioned at any
desired deflection angle, can be constructed of a variety of
materials that withstand the environment, and can exhibit a variety
of shapes and surfaces defined to produce the most advantageous
spray patterns for optimal smoke absorption. The baffles 24 can be
solid or porous and can exhibit any geometric shape that
facilitates the formation of the desired droplets and mist. The
baffles 24 are normally located near the tops of the towers 10,
although can be located anywhere along each tower 10. Multiple
baffles 24 can also be located in each tower 10.
[0022] Exhaust gases in the towers 10 mix with the droplets and
mist to heat the liquid spray and extract heat, particulates and
other contaminants emitted with the gases. For flue gases
approaching 900.degree. F., the liquid 16 in a nominal 70 cubic
foot tank 14 can be elevated to 160.degree. F. As the smoke is
absorbed, the droplets and mist fall under the influence of gravity
back into the tank 12. Any solid materials vented from the flue in
the smoke (e.g. ash, soot, heavy metals) are held in the tank 14
and typically collect at the top of the liquid 16, settle to the
bottom or are suspended as particulates.
[0023] The liquid 16 is maintained in the tank to a level that
forms a space 26 between the top of the liquid 16 and the cover or
canopy assembly 12. The channel space 26 can be in the range of 8
to 18 inches. The channel space 26 allows the exhaust gases to flow
from the boiler 2 and sequentially into each of the towers 10. As
noted at FIG. 1 the gases are depicted to be denser (i.e. darker)
nearer the boiler 4 and progressively less dense as each tower 10
is traversed, until only water or steam is emitted from the exit
port 28 of the rightmost tower 10.
[0024] The cover or canopy 12 can be constructed of plastic,
stainless steel or other suitable materials or composites resistant
to the working environment. Suitable conduits, baffles or fans can
also be provided in the space 26 to direct the gases between the
towers 10. Conduits might also be provided in the space 26 to
direct a portion of the exhaust gases directly into the liquid 16
in the tank 14 in the fashion of a bubbler to facilitate the
extraction of heat and contaminants.
[0025] The leftmost tower 10 also includes a bracket 28 that
supports the tower 10 and weight of the intersecting flue piece 6.
A funnel piece 30 mounted to the bottom of the leftmost riser
portion of the tower captures the falling water and prevents a
downward draft and flow of exhaust gases into the tank 14 rather
that up and into the series of towers 10.
[0026] Distributed about the liquid containment tank 14 are a
number of sensors or electrodes. A sensor 32 (e.g. a float)
monitors liquid depth. Another sensor 34 monitors liquid
temperature. Another servo 36 (e.g. solenoid valve) cooperates with
the sensor 32 to admit additional liquid 16 into the tank 14. Yet
another servo 38 can cooperate with the sensor 34 to circulate the
heated liquid 16 into the heat exchanger 4 and conduit/radiator
system 5.
[0027] The heat extracted from the exhaust gases and stored in the
liquid 16 is returned to the heat exchanger 4 via the conduit
system 20 and/or to the external thermal transfer conduit/radiator
system 5. The liquid 16 is normally separately treated for acidity
and other chemical changes. Also added to the liquid 16 to soften
the water and enhance smoke collection is a mixture of soda (e.g.
Sal soda) and a sudsing agent (e.g. tide soap).
[0028] A separate heat exchange coil 7 coupled for example to a
domestic hot water system might also be mounted in the tank 14 to
heat the domestic water. Supply and return air ducts or conduits 9
and 11 of a heating, ventilating and air conditioning system at the
premises (HVAC) might also be fitted to the cover 12 to humidify a
supply of air passed through the tank 14 in the space 26 adjacent a
smoke free portion of the space 26 and returned to the heated
premises.
[0029] As mentioned, effluents frequently collect on the surface of
the liquid 16 in the form of a floating moss or agglutination of
contaminants. These flotsam materials are skimmed off the liquid 16
with rotating paddles assemblies 40 and 42. The assemblies 40 and
42 presently each provide several laterally displaced paddle arms
or any desired shape that project from an axle that is rotated to
cause the paddles to direct the surface effluent to a collection
point or chute. The effluent may also collect as suspended
particulates in the liquid 16. Rake tines, an auger, strainer or a
variety of other assemblies may alternatively or in combination
with each other be used to periodically draw the solid effluents
from the liquid 16.
[0030] The collected materials can be dried and then conveyed to a
separate incinerator or back to the burn chamber at the boiler 4 to
be re-burned. Alternatively, the materials can be disposed of
through other suitable means or mechanisms.
[0031] Also provided at the tank 14 is a filtration assembly 44
that can take a variety of forms. Appropriate filter media and
supports can be appropriately located about the tank 14. The
filtration assembly 44 can be selected to filter any desired
contaminant, soot, heavy metal, or any other chemical or
particulate found in the spray liquid 16.
[0032] A system controller 50 (e.g. microprocessor based) can be
coupled with suitable conductors or wirelessly to monitor the
foregoing liquid level and temperature sensors 32 and 34, filter
assembly(s) 44 and collected effluents. The controller 50 can
direct the servos 36 and 38, as well as monitor water clarity,
surface debris and direct any associated filtration assembly 44 or
the skimmer assemblies 40 and 42 and/or any collector or
incinerator assembly that might be provided to collect, remove or
incinerate collected contaminants or effluents. Alternatively, a
conveyor (e.g. auger based) can be provided to direct the collected
debris back into the burn chamber of the furnace 2.
[0033] While the invention is shown and described with respect to a
presently preferred assembly and several considered improvements,
modifications and/or alternatives thereto, still other assemblies
and arrangements may be suggested to those skilled in the art. It
is to be appreciated therefore that the features of the disclosed
heating system can be arranged in different combinations. For
example, the towers can be serially coupled or coupled in parallel
to the collection tank. Contaminant filters and/or a rake or
skimmer assembly can be fitted to the tank to extract suspended
contaminants. The primary thermal transfer assembly or a separate
assembly (e.g. radiator) can be coupled to the tank. The foregoing
description should therefore be construed to include all those
embodiments within the spirit and scope of the following
claims.
* * * * *