Note: Descriptions are shown in the official language in which they were submitted.
20766~1
DISTILLATION GASIFICATION COMBUSTION EQUIPMENT AND
DRY DISTILLATION GAS GENERATOR THEREFOR
This invention relates to a dry ~ till~tion gas generator adapted for heating a
5 solid fuel, e.g., a high molecular weight material such as rubber or plastic, etc., or tire,
etc. to convert the solid fuel to a combustible gas by heat decomposition, and to a dry
(listill~tion gasification combustion equipment in which a combustion burner unit for
burning a generated dry distillation gas is combined with the dry riistill~tion gas
generator. Our copending application number 2,149,858 relates to a combustion burner
10 unit suitable for use in the dry (li~till~tion gasification combustion equipment.
A solid fuel combustion equipment with an upward combustion system disclosed
in Japanese Laid Open Patent Application No. 231307/1984 has a combustion unit
provided on a tlictill~tion unit for converting a solid fuel to a ~ till~tion gas. A heat
exchange unit is provided at the upper part thereof to generate a clistill~tion gas at the
15 lower part thereof and to burn this gas as it rises through the heat exchange unit. An air
supply means delivers a small quantity of air at the bottom portion of the distillation unit.
It is seen from the figure that an upward air-supply opening is bored at the bottom
portion thereof.
While it can be said that the above-described equipment is, in principle, a sort2 o of dry listill~tion gasification combustion equipment, it is only a structure in which the
dry (listill~tion unit and the combustion unit are continuous in upper and lower directions
It is not a structure in which both units are clearly partitioned.
Referring to the dry distillation unit of this equipment, insufficient consideration
is given to generation efficiency of the dry ~i~till~tion gas and to making the dry
2 5 distillation gasification process as clean as possible. Therefore, environmental problems
such as the generation of soot and smoke or dust, or odor remain unsolved.
The few air supply holes bored in the bottom of this unit tend to become choked
or clogged up with ashes from the combustion taking place therein. Consequently,unstable performance of the apparatus reduces the production efficiency of the dry
3 o tlistill~tion gas; or stoppage of production of the distillation occurs.
To continue operation, an operator must clean out the small air supply holes by
inserting a driver, or the like, into individual holes to scrape away ashes thel~rlolll. This
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is tedious work, and its necessity substantially reduces the effectiveness of the
equipment.
As stated above, the conventional equipment is unsatisfactory in its efficiency in
the production of dry distillation gas, the generation of clean dry distillation gas, and in
its performance stability. In addition, the difficulty in cleaning and maintenance are
substantial drawbacks.
Further the combustion unit of this prior-art unit burns dry distillation gas only
within a broad combustion chamber wherein dry (listill~tion gas is mixed with air
together with soot and smoke or dust, etc. Accordingly, it is impossible to adjust
0 combustion to attain complete, clean, combustion.
A gasification fuel combustion equipment for burning gasified fuel obtained by
means such as dry ~ till~tion, etc. is disclosed in Japanese Patent Publication No.
29365/1990. In this equipment, as in the equipment of the invention of this application,
the combustion equipment of the burner system is adapted for completely burning a fuel
once gasified by dry distillation or other means.
However, since this prior art equipment uses a rectification cylinder within a
cylindrical combustion chamber, thus to agitate and mix air blown off from small holes
with combustion gas, this equipment is satisfactory when use begins, but such holes
become clogged after a little use. Furthermore, the internal structure is complicated, and
2 o its cleaning and/or maintenance are very difficult.
It is an object of the present invention to provide a dry distillation gasification
combustion equipment and a dry (listill~tion gas generator which overcome the drawbacks
of the prior art.
It is a further object of the present invention to provide a system which offersefficient generation of dry combustion gas from a high-molecular weight fuel, and in
which combustion is controllable to provide a clean effluent.
It is a still further object of the present invention to provide a combination of a
dry ~ till~tion gas generator and a combustion gas burner which has high performance,
is easy to handle, and has high utility.
3 o Studies on the technical problems to be solved by the present invention are as
follows. First, the technical problem of the combustion burner unit will be described.
Since the combustion burner unit is exposed to high temperature at all times, it can
become damaged, and permit burning materials to be ejected, or to become attached
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thereto. For this reason, frequent maintenance of this type of equipment is expected.
Accordingly, embodiments of the present invention employ a combustion burner unit
having a burner with a simple internal structure having few, if any, uneven portions, so
that cleaning is simplified.
To resist the high temperatures of combustion, the cylindrical burner body of the
combustion burner unit of embodiments of the present invention is made of materials
having excellent heat resisting properties. In order to realize complete combustion, the
combustion burner unit provides excellent agitation and mixture of fuel with air to
improve the combustion speed and/or efficiency.
1 o The technical problem of the dry distillation gas generator will now be described.
In order to burn and heat a solid fuel, e.g., high molecular weight material such as
rubber or plastic, or tires, etc., within a dry distillation gas genelator, in order to
produce a dry ~ till~ion gasified fuel by thermal decomposition, the oxygen supply for
combustion must be controlled to a value low enough to allow a limited weak combustion
state to last for a long time, but high enough to burn a sufficient portion of the solid fuel
to thermally decompose the remainder. This requires the amount of combustion heat to
be sufficient to allow only a portion of solid fuel to burn weakly over a long time, while
the combustion heat decomposes the remainder of the solid fuel to a gaseous fuel.
However, it is a difficult technical problem to m~int~in and control the dry
2 o ~ till~tion conditions through control of the combustion heating system to generate a
stable supply of clean combustible gas from a solid fuel such as tires. In the prior art,
satisfactory combustible gas was not achievable.
In actual terms, it is first pointed out that controlling the air supply to m~int~in
distillation conditions in which combustion and heating are well-balanced is technically
2 5 difficult.
Secondly, it is difficult to deliver air in a gentle even manner to reduce expulsion
of soot and dust such as carbon, etc. and thereby produce clean combustible gas in a
stable marmer.
Thirdly, many solid fuels such as, for example, tires, contain impurities which,3 o when burned and heated, produce byproduct h~l~uliLies such as tar, carbon, wire, spike
tire pins or sand. These byproduct impurities can melt together to produce solid waste,
be reduced to ashes, or otherwise result in unburned residual material. Such residual
material can clog air blowoff openings. Such clogging destabilizes the supply of air, thus
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- making it difficult to maintAin stable combustion in which the conditions for dry
distillation are satisfied.
Fourthly, it is difficult to find an easy way to elimin~tç residual hll~uliLies within
a dry ~ tillation gas generator to simplify cleaning thereof, thus to prevent lowering of
5 the distillation gas generation long-term efficiency.
This invention contemplates solving the technical problems as described above.
The technical problem of the invention concerning the dry distillation gasification
combustion equipment will be now described.
In recent dry distillation gasification combustion equipment, the key problems are
10 how to stably produce clean combustible gas from a solid fuel in the dry distillation gas
generator and how to burn the combustible gas in the combustion gas burner unit.However, there is the problem that, while a double combustion system may be employed
merely to burn a solid fuel primarily within a dry distillation gas generator to generate
dry distillation gas and secondarily to burn it at the combustion unit, thereby to burn it
15 with an efficiency as high as possible, such a system cannot cope with the recent
~nvilol~lllental problem such as soot and smoke or dust, or odor, etc.
The inventor of this application contemplates a dry ~ tillation gas generator for
generating dry distillation gas and a combustion gas burner unit for completely burning
gasified fuel which are completely partitioned or divided, thus to improve respective
2 o functions thereof as far as possible. Especially, the inventor has drawn attention to the
fact that, in order to burn a solid fuel completely enough to prevent the production of
soot, smoke or odor, etc., the dry distillation gas must be as clean as possible, with a
predetçrmin~cl quantity of the dry di~tillation gas produced in a stable state at all times.
With the above in view, the inventor has advantageously adopted a scheme to improve
2 5 first the portions of the dry distillation gas generator and the air supply means, and to
provide an hll~uli~y separation tank in the middle of a gas conduit interconnecting the
dry fli~tillation gas generator and the combustion gas burner unit to improve cleanliness
of dr,v distillation gas delivered into the combustion gas burner unit.
According to a first aspect of the present invention, there is provided a dry
3 o ~i~tillation gasification combustion equipment comprising:
a dry distillation gas generator;
said dry ~ tillation gas generator including a tank furnace;
an air chamber in a bottom of said tank furnace;
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an air blowoff section colu",u~icating from said air chamber to a bottom portionof said tank furnace;
said air blowoff section including an air vent recessed portion bored in a bottom
surface of said tank furnace,
an air duct allowing for pe"lli~ g air from said air chamber to pass to a centerof said air vent recessed portion;
an air dispersion cap fitted into an opening of said air duct;
an upper surface of said air dispersion cap forming a portion of a bottom surface
of said tank furnace;
lo a blowoff opening about a circumference of said air dispersion cap;
said blowoff opening supplying air from said air duct in a decelerated and
dispersed state substantially uniformly into the tank furnace from said circumference of
said blowoff opening;
said air softly and evenly spreading over the entire bottom surface of said tank1 5 furnace;
a fuel door in said tank furnace, effective for perrnitting entry of a dry fuel into
said tank furnace;
said fuel door being openable and closeable;
a dry ~ till~tion gas outlet from said tank furnace;
2 o a combustion gas burner unit;
a gas conduit conducting dry ~ till~tion gas from said dry distillation gas outlet
to said combustion gas burner unit;
said combustion gas burner unit including a burner body;
a combustion chamber in said combustion gas burner unit receiving gas from said
2 5 gas conduit;
said combustion chamber including a preheat burner section for igniting a pilot
at a position close to an upstream end of said combustion chamber;
an air storage layer surrounding an outer circumferential surface of an
intermediate portion of said combustion chamber;
3 o a first air supply section skewed an angle for injecting air rotating in a spiral from
the outside through a side wall of said combustion chamber;
a second air supply section skewed at an angle for injecting air in a spiral from
said air storage layer through said side wall;
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said air injected by said second air supply section being preheated in said air
storage layer and injected in said combustion chamber at a position downstream of the
injection of air by said first air supply section; and
an h~ uliLy separation tank in said gas conduit at a position intermediate said tank
furnace and said combustion gas burner unit for separating in~ulilies from said dry
distillation gas before applying it to said combustion gas burner unit.
In accordance with a second aspect of the present invention, there is provided adry tlistill~tion gasification combustion equipment comprising:
a tank furnace;
0 means for entering a solid fuel in said tank furnace;
a cooling layer about a substantial portion of said tank furnace;
a bottom of said tank furnace including a triple layer structure including first,
second and third layers;
said first layer including a heat resisting material;
said second layer including a cooling layer;
said third layer including an air chamber;
a plurality of air blowoff portions in said bottom;
each of said air blowoff portions an air vent recessed portion bored in said first
layer and an air duct collllllunicating air from said air chamber to said air vent recessed
2 o portion;
an air dispersion cap fitted into each air duct;
an upper surface of each air dispersion cap forming a portion of said first layer;
means for p~ ing air to pass said air dispersion cap substantially uniformly
in a decelerated and dispersed state in a lateral direction into the tank furnace from a
blowoff opening on a cil~;unlfelellce of each air dispersion cap toward the lateral
direction, the supplied air softly and evenly spreading over the entire bottom surface
along the air vent recessed portion around the air dispersion cap;
a combustion gas burner unit;
said combustion gas burner unit including a burner body;
3 o a gas conduit section conntocting dry distillate fuel gas from said tank furnace to
said combustion gas burner;
said burner body including a combustion chamber;
a preheat burner section at an upstream end of said combustion chamber;
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a pilot in said preheat burner for igniting said dry ~listill~te gas;
an air storage layer surrounding a substantial circumferential portion of said;
a first air supply section opening from the outside through a side wall of said
burner body at an angle rotated in a spiral;
a second air supply section opening from said air supply layer through said sidewall at an angle rotated in a spiral;
said first air supply section entering said burner body at a position upstream of
a position where said second air supply section enters said burner body;
air in said air supply layer being preheated before being injected into said burner
0 body; and
an im~uliLy separation tank at an intermediate position in said gas conduit for
removing i,ll~uli~ies from said dry di~till~tion gas.
According to a third aspect of the present invention, there is provided a dry
distillation gas generator comprising:
a tank furnace;
a combustion chamber in said tank furnace;
means for entering a fuel into said combustion chamber;
a dry distillation gas outlet from said combustion chamber;
an air chamber below a bottom of said combustion chamber;
an air blow-off section col"~llul-icating air from said air chamber to a bottom
portion of said tank furnace;
said air blowoff section including at least one air vent recessed portion bored in
a bottom surface of said combustion chamber;
an air duct co~ ul-icating air from said air chamber to said at least one air vent
2 5 recessed portion;
an air dispersion cap fitted into said air duct;
an upper surface of said air dispersion cap forming a portion of said bottom
surface;
a blowoff opening about a circumference of said air dispersion cap;
3 0 said blowoff opening supplying air radially therefrom substantially uniformly in
a decelerated and dispersed state into said tank furnace, the supplied air softly and evenly
spreading over said bottom surface.
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According to a fourth aspect of the present invention, there is provided a dry
distillation gas generator comprising:
a tank furnace;
a fuel door in said tank furnace adapted to being opened and closed;
a dry ~ till~tion gas outlet from said tank furnace;
a cooling layer surrounding a substantial portion of an outer circumferential
surface of the tank furnace;
a bottom portion of said tank furnace including first, second and third layers;
said first layer being a heat resisting material;
lo said second layer being a cooling layer below said first layer;
said third layer being an air chamber below said cooling layer;
a plurality of air blowoff portions in said bottom portion;
each air blowoff portion including an air vent recessed portion bored in said first
layer;
an air duct co~ llunicating air from said air chamber to said air vent recessed
portion;
an air dispersion cap being fitted into said air duct;
an upper surface of said air dispersion cap forming a portion of said a bottom
surface of said tank furnace;
means for permitting air entering said tank furnace to be supplied radially fromsaid air dispersion cap and to enter said tank furnace substantially uniformly in a
decelerated and dispersed state and to softly and evenly spread over the entire bottom
surface along the air vent recessed portion around the air dispersion cap.
According to a fifth aspect of the present invention, there is provided a dry
distillate gas generator comprising:
a tank furnace;
means for loading a solid fuel in said tank furnace;
a bottom in said tank furnace;
an air chamber below said bottom;
3 o an air duct connecting said air chamber through said bottom;
an air dispersion cap in a top of said air duct;
a tapered lower surface on said air dispersion cap;
at least one projection on said tapered lower surface;
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said at least one projection being effective for m~int~ining said tapered lower
surface out of contact with said air duct, whereby at least one blow-off hole ism~int~ined between said tapered lower surface and said air duct; and
said blow-off hole being inclined to enter air above said bottom generally radially,
and in a slow, gentle flow.
According to a sixth aspect of the present invention, there is provided a dry
till~te gas generator and a combustion apparatus comprising:
a tank furnace;
sealable means for adding a solid fuel to said tank furnace;
means for flowing air into a bottom of said tank furnace in a generally radial flow
across said bottom, in a flow effective to combust no more than a portion of said solid
fuel, and to thermally decompose a remainder of said solid fuel to produce a drydistillate gas;
a combustion chamber;
a gas conduit connecting said dry distillate gas from said tank furnace to said
combustion chamber;
an impurity separation tank in said gas conduit;
an air storage layer surrounding said combustion chamber;
a preheat burner in an upstream end of said combustion chamber;
means for injecting a first supply of air from outside said combustion chamber
into said combustion chamber downstream of said preheat burner;
means for injecting a second supply of air from said air storage layer into saidcombustion chamber dowll~L~ l of an injection point of first supply of air; and
said first means for injecting and said second means for injecting including means
2 5 for spiralling air injected into said combustion chamber whereby agitation and mixing
of air with said dry distillate gas is enabled.
According to a first aspect of the invention disclosed and claimed in copending
applicatlon number 2,149,858, there is provided a combustion gas burner unit
comprlsmg:
3 0 a burner body having a longitll~lin~l axis;
a gas conduit portion at bottom end portion of said burner body;
a combustion chamber in said burner body;
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-- a preheat burner section for igniting a pilot at a position close to an upstream end
of said combustion chamber;
an air storage layer surrounding a substantial portion of a circumference of said
combustion chamber;
a first air supply section from outside to an interior of said combustion chamber,
skewed at a first angle for rotating injected air in a spiral;
a second air supply section from said air storage layer to said interior, skewedat a second angle for rotating air injected air in a spiral;
said second angle having a shallower forward angle with respect to said
lo longit~1(1in~l axis than said first angle, thereby producing a higher component of air
velocity along axis of said burner body;
an injection point of said first air supply section being upstream of an injection
point of said second air supply section;
air injected through said second air supply section being preheated in said air
storage layer; and
said first and second angles being effective for ~git~ting and mixing a dry
distillate fuel gas with air from said first and second air supply sections.
According to a second aspect of the invention disclosed and claimed in copendingapplication number 2,149,858, there is provided a combustion apparatus for burning a
fuel gas comprising:
a combustion chamber;
an air storage layer surrounding said combustion chamber;
said air storage layer receiving heat from said combustion chamber to preheat air
therein;
2 5 means for flowing said fuel gas through said combustion chamber;
first means for injecting a first supply of air from outside said combustion
chamber into said combustion chamber;
second means for injecting a second supply of preheated air from said air storage
layer into said combustion chamber;
air injected by said second means being injected downstream of a location at
which air is injected by said first means; and
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said first means and said second means both including means for producing a
spiral flow of air in said combustion chamber, whereby agitation and mixing of said fuel
gas with said air is enabled; and
said second means including means to produce a higher component of air velocity
5 along a longitll-lin~l axis of a burner body than said first means.
In embodiments of any of the foregoing aspects of the present invention, the
burner body may be formed of a refractory material such as ceramic.
The dry ~ till~tion gasification combustion equipment may have a gas conduit
conn~cte(l to a dry ~ till~tion gas outlet of the dry (lictill~tion gas generator to provide
10 an hll~uliLy separation tank in the gas conduit connected to the gas burner unit.
In embodiments of the present invention, when a solid fuel such as a tire, etc. is
~lmittctl from the fuel entry portion into the tank furnace and air is ~tlmitte~l from the
air chamber at the bottom portion thereof, a predetermined quantity of air is supplied
into the dry distillation gas generator through the air blowoff section commnnicating with
15 the air chamber. Since the air blowoff section is comprised of the air vent recessed
portion bored at a suitable portion of the bottom surface of the tank furnace, the air duct
communicates between the air chamber provided at the central portion of the air vent
recessed portion and the interior of the tank furnace. The air dispersion cap fitted into
the air duct, and the blowoff hole formed at the circumferential side of the air dispersion
20 cap, cause air blown from the air duct to be supplied into the tank furnace in a
decelerated and dispersed fashion substantially uniformly and laterally from the blowoff
hole such that the supplied air spreads softly and evenly over the entire bottom surface.
When the accommodated solid fuel, such as a tire, etc., is ignited, only the
portion of the solid fuel in the vicinity of the bottom portion of the tank furnace where
2 5 air spreads is burned.
At that time, the upper surface of the air dispersion cap serves as a portion of the
bottom surface of the tank furnace such that there is no projecting portion. Thus,
accornmodation of the solid fuel is easy.
Where the blowoff hole is formed on the circumferential side of the air dispersion
3 o cap, and the air vent recessed portion is formed therearound, there is no possibility of
the air blowoff opening being inadvertently clogged by the solid fuel. In addition, since
air forcefully spreads in a lateral direction through the air vent recessed section, and air
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which has lost its force is dispersed and supplied softly in an upward direction, there
results a state in which air spreads softly and evenly at all times.
As a result, the combustion area of the solid fuel is limited to the portion in the
vicinity of the bottom where air is stably supplied, but does not spread over other
portions. Such stabilized partial combustion in the vicinity of the bottom portion heats
the solid fuel thereabout so that thermal decomposition is produced. Thus, dry (li~t~ tion
gas is efficiently and stably generated. Since, at all times, the air is softly diffused and
supplied, there is no possibility that carbon will be picked up to float in the air within
the tank furnace, thus permitting the dry distillation gas produced to be a clean gas
having less hlly-lliLies.
Gas distillation gasification combustion equipment employing the dry ~ till~tiongas generator as stated above and making use of the impurity separation tank provided
in the gas conduit to introduce the gas into the combustion gas burner unit efficiently and
stably provides a cleaner dry (li~till~tion gas having less illll)ufilies.
The clean, dry 11istill~tion gas introduced from the gas conduit of the burner body
is agit~tecl and mixed, while rotating, with the air blown off and delivered from the
opening of the first air supply section within the cylindrical burner body heated in
advance by the preheat burner section, and is introduced in a direction of the combustion
chamber at the front end thereof. The dry (ii~till~tion air thus introduced is ignited by a
pilot of the preheating burner unit, and is guided in a direction of the combustion
chamber at the front end portion. The dry distillation gas thus introduced is ignited by
a pilot of the preheat burner section, so it is burned while blowing out flame from the
combustion chamber. In this instance, in the vicinity of the combustion chamber, the air
preheated by the air storage layer is further delivered from the second air supply portion,
2 5 and is agit~t~l and mixed with combustion gas, thus further assisting combustion.
By employing such a configuration, a clean dry distillation gas is completely
burned at the combustion gas burner unit.
In embodiments of the fourth aspect of the invention having a cooling layer
provided at the entire outer circumference of the tank furnace, whose bottom portion is
3 o of a triple layer structure with the bottom surface made up of a heat resisting material,
cooling layer and air chamber, and a cleaning port provided at the side portion of the air
chamber, the configuration thus featured provides the following effect:
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-- First, the presence of the cooling layer on the entire outer ch~;ulllfe~ ce of the
tank furnace suppresses temperature elevation within the tank furnace to prevent extra
or lmn~ces~ry combustion except for portions in the vicinity of the bottom portion of
the solid fuel, thus reducing soot and smoke or dust and floating particulates as much as
5 possible.
Since the bottom portion is a triple layer structure, the high temperature portion
on the surface of the bottom has sufficient durability. Further the cooling layer prevents
the temperature of the bottom portion of the tank furnace from rising higher than is
required. The large air chamber permits an even supply of air over the entire bottom
10 portion. The supplied air is pre-heated.
In addition, the cleaning port at the side of the air chamber permits easy cleaning
of acc~lm~ te~l residual i~ ulilies that may have dropped through the air duct.
By using the dry tli~till~tion gas generator as stated above, the dry distillation
gasification combustion equipment of this fourth aspect of the invention efficiently and
5 stably generates dry distillation gas including less impurities to allow it to serve as a
cleaner dry distillation gas. This cleanliness is further improved by the hll~ulily
separation tank in the middle of the gas conduit. The dry distillation gas generated by
the dry distillation gas generator of the embodiments of the fourth aspect of the invention
has a cleanness higher than that of the embodiments of the first aspect of the invention.
The dry distillation gas is sufficiently clean to be completely burned in the
combustion gas burner unit. Since the effect within the combustion gas burner unit is the
same as that within the combustion gas burner unit described in respect of the first aspect
of the invention, its explanation is omitted here.
Since the effect of the dry distillation gas generator of the third aspect of the
2 5 invention is the same as that of the dry distillation gas generator of the first aspect of the
invention, and the effect of the dry distillation gas generator of the fourth aspect of the
invention is the same as that of the first aspect of the invention, their explanation is
omitted here.
In addition, the effect within the combustion gas burner unit of the fifth aspect
of the invention is also the same as that of the first aspect of the invention, its
explanation is omitted here.
Briefly stated, one aspect of the present invention provides a dry distillation gas
generator which generates a dry distillation gas for burning in a separate combustion gas
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burner unit. Air is supplied in a gentle decelerated flow to the bottom of the dry
cli~till~tion gas generator in a quantity sufficient to support combustion of a solid fuel in
the vicinity of the air supply, but at a low enough volume to prevent the combustion
procee-lin~ to other parts of the gas generator, thus thermally decomposing the remainder
of the solid fuel to generate the dry distillate gas. An air chamber surrounds the gas
generator to reduce the temperature to which the solid fuel is exposed. Similarly, an air
chamber is disposed below the bottom of the gas generator to supply air to the gas
generator, and to moderate the temperature therein. An i~ ulily separation tank in a
conduit between the gas generator and the gas burner unit helps prevent particulates from
0 entering the gas generator. A preheat burner in the combustion gas burner unit includes
a pilot to ignite and preheat the gas. A first air injection device injects air from outside
the gas burner in a spiral flow to agitate and mix the gas with air. A second air injection
device injects air preheated in an air storage layer surrounding the gas burner unit into
the gas burner in a spiral flow to further agitate and mix the gas with air. The injection
point of the second air injection device is downstream of the injection point of the first
air injection device.
The above, and other objects, features and advantages of the present invention
will become apl?arellL from the following description read in conjunction with the
accompanying drawings, in which like reference numerals designate the same elements.
In the drawings:
Figure 1 is a side view showing a dry ~ till~tion gasification combustion
equipment;
Figure 2 is a front view showing a dry distillation gas generator;
Figure 3 is a longihl~lin~l cross sectional side elevation showing the
2 5 structure of the bottom portion within the tank furnace;
Figure 4 is a plan view showing the structure of the bottom portion shown
in Figure 3;
Figure 5 is a longit~-lin~l cross sectional side elevation showing the
configuration of an air duct of the air blowoff portion;
3 o Figure 6 is a perspective view showing an air dispersion cap;
Figure 7 is a bottom view showing an air dispersion cap;
Figure 8 is a longitll(lin~l cross sectional explanatory view showing the
state where the air blowoff portion is attached on the bottom portion;
14
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Figure 9 is a longihl(lin~l cross sectional plan view of a combustion gas
burner unit; and
Figure 10 is a side view of the combustion gas burner unit.
Referring to Figures 1 and 2, the dry distillation gasification combustion
equipment of the present invention includes a dry (li~till~tion gas generator 1 and a
combustion gas burner unit which are separate units connected together by means of a
gas conduit 4. An illl~uliLy separation tank 3 is positioned in the middle portion of gas
conduit 4. (The combustion gas burner itself is the subject of our copending patent
application number 2,149,858.)
The dry distillation gasification combustion equipment of the embodiment shown
is especially adaptable for burning used tires and for generating dry distillation gas
thererl.~lll to completely burn used tires, thus providing thermal energy. In accordance
with this equipment, the gas conduit 4 is connected to a dry distillation gas outlet 5 at
the rear of dry ~lictill~tion gas generator 1. A combustion gas burner unit 2 is connected
to the end of the gas conduit 4.
Dry distillation gas generator 1 includes a tank furnace 7 made of carbon steel,having a fuel throw-in portion 6, or feed door, adapted so that it can be opened and
closed to receive solid fuel. Dry distillation gas outlet 5 is conn~ctç~l to tank furnace 7.
A safety valve 8 at the top of the tank furnace 7 permits the discharge of
excessive pressure from tank furnace 7 in the event of a malfunction. A further safety
valve 8a, shown in dashed lines in Figure 2, may be provided according to need.
Referring now to FIGS. 3 and 4, fuel throw-in portion 6 includes a tank door 6c
that can be opened and closed to reveal a large fuel entrance/exit 6a at the front side of
2 5 the tank furnace 7. Screw-type sealing devices 6b, or clamps, hold tank door 6c sealed
over entrance/exit 6a to prevent the loss of fuel gas thel~lluough. The large size of fuel
entrance/exit 6a eases feeding of a stack of solid fuel into the tank furnace 7, and
removing residual material after combustion. The large size of fuel entrance/exit 6a also
simplifies cleaning of the interior of tank furnace 7.
3 o Although the embodiment shown employs a single dry ~ till~tion gas outlet 5 in
the rear of tank furnace 7, one skilled in the art will recognize that additional dry
tli.~till~tion gas outlets (not shown) may be added about the cil.;ulll~elellce of tank furnace
7 without departing from the spirit and scope of the invention. If a plurality of dry
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-- distillation gas outlets are included, a single one may be chosen as required by piping
requirements, or, alternatively, two or more dry ~ till~tion gas outlets may be employed
siml-lt~n~ously to convey the dry distillation gas from tank furnace 7.
A cooling layer 9 encircles the entire circumference of the tank furnace 7.
5 Cooling water is circulated in cooling layer 9 to control the temperature of the outside
wall of tank furnace 7.
Cooling layer 9 extends behind the packing of tank door 6c covering fuel
entrance/exit 6a. The portion of cooling layer 9 in this region avoids accelerated heat
aging of the packing sealing tank door 6c, thereby enabling long-term use of theo equipment.
The bottom portion of the tank furnace 7 is a triple layer structure. The upper
part of the triple layer structure is a bottom surface 10 of a heat resisting material such
as a refractory material. Cooling layer 9 extends under bottom surface 10. An air
chamber 11 is located below cooling layer 9. Removable clearing ports lla at the sides
15 of air chamber 11 permit purging of debris therefrom.
The inner circumferential surfaces of the lower portions of the bottom surface 10
and the tank furnace 7 are exposed to combustion heat. Consequently, at least these
portions of the interior of tank furnace 7 are lined with a refractory (ceramic) material
for its heat-resisting properties.
The cooling layer 9 forms a water jacket system in which cooling water is
contained at the outside of the bottom surface 10, and is adapted to cool the bottom
surface 10 subject to high temperature, thus to realize protection thereof and an increased
durable life. The air chamber 11 formed outside the cooling layer 9 is in the form of an
air chamber formed on the entire surface of the bottom portion, and is of a structure
2 5 such that blowoff of air is caused to be uniform, and that a n~cess~ry quantity of air can
be supplied at any time.
At the bottom portion of the tank furnace 7, a plurality of air blowoff portions12 are distributed substantially uniformly over the area of bottom surface 10.
Referring now to FIGS. 5, 6, 7 and 8, each of the air blowoff portions 12
3 o includes an air vent recessed portion 13 recessed in bottom surface 10. An air duct 14
commllnicates air between air chamber 11 and the center of the air vent recessed portion
13 to permit the flow of air thele~ ough into the interior of tank furnace 7. An air
dispersion cap 15 is fitted at the top of each air duct 14.
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Referring specifically to Figure 5, air duct 14 includes a fiKing member 19
including an air dispersion cap receiving portion 17 at the upper end opening portion of
a tubular body 16. An embedded projecting portion 18 projects ~ulw~ld from air duct
14. Embedded projecting portion 18 is embedded in bottom surface 10. A cylindrical
body 20 (Figure 8) extends downwal-l from tubular body 16, through cooling layer 9,
and to air chamber 11.
Referring again to FIGS. 6, 7 and 8, air dispersion cap 15 is a heat resisting
special casting in the form of an inverse triangular cone, as shown in FIGS. 6 and 7. An
upper surface 21 of air dispersion cap 15 is flat. A lower surface of air dispersion cap
0 15 is a tapered surface 22. A plurality of radial projections 23 extend down tapered
surface 22. Centering projections 24 at a lower end of air dispersion cap 15 contact the
inner surface of air duct 14 to m~int~in air dispersion cap 15 centered with respect to air
duct 14. The radial projections 23 and the air dispersion cap receiving portion 17
m~int~in a blowoff channel or hole 25 between the air dispersion cap receiving portion
17 and the tapered surface 22.
Upper surface 21 of air dispersion cap 15, fitted into the opening in the tank
furnace 7, forms a portion of the bottom surface 10 of tank furnace 7. Air entering from
air duct 14 is decelerated and dispersed to enter tank furnace 7 substantially uniformly
through ouLw~rdly tapering blowoff holes 25 between the side of air dispersion cap 15
and air dispersion cap receiving portion 17. The air thus supplied spreads softly and
evenly over the entire bottom surface 10 along the air vent recessed portion 13 around
the air dispersion cap 15.
As described above, in accordance with this invention, air blowoff portions 12
are made up of the air duct 14 and the air dispersion cap 15. Air duct 14 is fixed in the
bottom of tank furnace 7 and air dispersion cap 15 is removably fixed in air duct 14.
This makes it possible to cope with expansion and distortion due to heat over a long
period of use. Further, air dispersion cap 15 can be removed to simplify cleaning,
exchange, and/or maintenance thereof.
It is to be noted that, although not shown, tank furnace 7 includes a temperature
3 o sensor for monitoring the temperature of the dry distillation gas produced, a sensor for
automatically controlling the quantity of gas produced after the temperature reaches a
predetermined temperature (150 degree(s) to 200 degree(s) C.), and an electromagnetic
valve for allowing air to be completely sealed off when the power supply is interrupted
- 2076651
`-- either intentionally or due to primary power hl~ell.lplion. Such sensing and control
enables complete control of the process of dry distillation of solid fuel.
Referring now to FIGS. 9 and 10, combustion gas burner unit 2 includes a
cylindrical burner body 26, of a refractory material such as, for example, a ceramic.
5 A gas conduit portion 27 at the upstream end of burner body 26 admits dry distillate gas
from tank furnace 7. A combustion chamber 28 is provided at the downstream end of
burner body 26. A preheat burner unit 29 for igni~in~ a pilot flame is positioned in the
bottom of burner body 26, near its upstream end. An air storage layer 30 encircles the
outer cil.;unlr~ ce of an intermediate portion of burner body 26.
1 o It is to be noted that, although combustion chamber 28 is shown as a removable
structure, one skilled in the art will recognize that it may be integrally formed with
burner body 26 without departing from the spirit and scope of the invention.
A first air supply section 31 opens through the wall of burner body 26 at a
forward angle and a skew angle with respect to the longit~ldin:~l axis of burner body 26
1 5 to apply a forward velocity component and a rotating velocity component to the injected
air to cause the injected air to rotate in a forward-moving spiral within burner body 26.
A pair of second air supply sections 32 and 32 pass from air supply layer 30 to enter
burner body 26 at a position downstream of the entry of air supply section 31, and at a
shallower forward angle to produce a higher component of air velocity along the axis of
2 o burner body 26. Second air supply sections 32 and 32 are also skewed with respect to
the longi~l-lin~l axis of burner body 26 to impart spiral rotation to the injected air. The
resulting along-axis and spiral motion of the injected air is illustrated by spiral lines in
Figure 9.
The spiral rotation imparted to the air by the skewed positioning of first air
supply section 31 and second air supply sections 32 and 32, tend to mix the fuel gas
passing through burner body 26 with the injected air.
Air storage layer 30 is preheated by heat conduction from the combustion within
burner body 26. As a consequence, the air from second air supply sections 32 and 32
is injected at an elevated temperature to improve combustion at the relatively downstream
3 o location of injection.
According to the foregoing, the present invention provides a dry distillation
gasification combustion equipment in which a dry ~listill;~tion gas generator, a combustion
gas burner unit, and an impurity separation tank are connected together by a gas conduit.
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2076651
An air blowoff section includes an air vent recessed portion bored in the bottom surface
of a tank furnace. An air duct feeds air through an air chamber in the center of the air
vent recessed portion into the interior of the tank furnace. An air dispersion cap located
in the air duct where it opens into the tank furnace forms a portion of the bottom surface
5 of the tank furnace. A blowoff opening is formed about the circumference of the air
dispersion cap so that air from the air duct enters the tank furnace substantially uniformly
in a decelerated and dispersed state in a radial direction. The supplied air thus spreads
softly and evenly over the entire bottom surface of the tank furnace. Accordingly, when
a solid fuel such as tires is loaded through fuel door into the tank furnace, air is supplied
o to the tank furnace uniformly, and in a decelerated and dispersed fashion. The slow
unirolm air flow prevents emission of embers and dust from the tank furnace. Air flow
control is suitable to limit the amount of air to that required to generate dry ~1istill~te fuel
gas from the solid fuel by burning only a portion of the solid fuel.
The dry (listill~tion gas generator of the present invention permits stable supply
15 of a predetermined quantity of air controlled so as to m~int~in the distillation condition
with balanced combustion and heating. For this reason, the combustion area is limited
to a portion of the solid fuel near the bottom portion where air is stably supplied. Such
stabilized partial combustion in the vicinity of the bottom portion heats the remainder of
the solid fuel in the tank furnace to produce thermal decomposition. Thus, dry
2 o distillation gas is efficiently and stably generated.
Since air supplied is softly diffused and supplied at all times, whirling or floating
up of carbon within the tank furnace is avoided, thus making it possible to generate clean
combustible gas in a stabilized manner.
The upper surface of the air dispersion cap forms a portion of the bottom surface
2 5 of the tank furnace. A blowoff opening about the circumference of the air dispersion cap
supplies air from the air duct into the tank furnace radially in a uniform, decelerated and
dispersed marmer.
The present invention provides the following advantages. When a solid fuel such
as tires is burned and heated, il--~uflLies such as tar, carbon, wire, spike tire pin, or
3 o sand, etc. are heated together, so that they are melted, are reduced to ashes, or result in
residual material. Such residual material cannot easily clog the air blowoff opening in
the bottom of the tank furnace. For this reason, the air supply remains stable in use,
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~076651
thus making it possible to stably m~int~in for a long time the heat/combustion state in
which the conditions for dry distillation are satisfied.
Since the air blowoff opening is large, it is easy to clean and remove residual
impurities from the dry distillation gas generator by removing the air dispersion cap.
This extends the time during which the dry distillation gas generation can operate.
The combustion gas burner unit burns the clean dry (ii~till~tion gas fed from the
tank furnace through a gas conduit. The dry distillation gas is ignited by a pilot burner
in a preheat burner section and is then rotated and mixed with air injected through a
skewed first air supply section of the burner body to enable further combustion. The first
l o air supply section injects air with a forward component of velocity along the axis of the
combustion gas burner. An air supply is preheated in an air storage layer before being
injected through a second air supply section into the combustion gas burner unit at a
location downstream of the injection by the first air supply section. The second air
supply section is skewed to rotate the injected air for agitation and mixing, and is
directed in the downstream direction to increase the travel velocity of the burning gas.
The second air supply section is less skewed, but its forward angle is greater than the
first air supply section. The combination of plentiful air supply and vigorous agitation
with preheating in the combustion burner unit provides efficient and complete combustion
of the clean dry distillation gas.
2 o The dry distillation gasification combustion equipment of the present invention
efficiently and stably generates a dry ~ till~tion gas including less impurities. An
hll~uliLy separation tank in the gas conduit carrying the gas to the combustion gas burner
unit traps hlll~ulilies (dust, embers, ashes, etc.) to deliver clean dry distillation gas to the
combustion gas burner unit. This permits the generation of thermal energy without the
emission of soot, smoke or dust into the environment. The dry distillation gasification
combustion equipment of the invention is combined with a combustion gas burner unit,
and an impurity separation tank connected together by a gas conduit.
A cooling layer about the entire outer circumference of the tank furnace lowers
the temperature therein to prevent extra or unnecessary combustion except at the portion
3 o in the vicinity of the bottom of the solid fuel to reduce the production of soot, smoke or
dust to a mh~illlulll, thus permi~ting production of a clear dry distillation gas.
Using a three-layer structure in the bottom of the tank furnace improves the
durability of the high temperature portion on the surface of the bottom portion. A cooling
~076651
layer, through which combustion air passes on its way to the interior of the tank furnace,
keeps the temperature of the bottom surface of the tank furnace at a relatively low
temperature without permitting the temperature to rise higher than is required. The air
passing through the cooling layer is pre-heated to improve the efficiency of the tank
5 furnace.
The sides of the air chamber include cleaning ports to enable the cleaning out of
residual ill~ulilies that may have dropped through the air duct in the bottom of the tank
furnace.
The i~ Uli~y separation tank in the middle of the gas conduit cleans the dry
o distillation gas to permit complete combustion in the combustion gas burner unit without
the emission of soot, dust or smoke.
Clean dry ~ till~tion gas from the gas conduit section of the burner body is
ignited by a pilot in a preheat burner section, and is then rotated, agitated and mixed
with air from openings of the first and second air supply sections within the cylindrical
15 burner body.
Having described pl~efelled embodiments of the invention with reference to the
accompanying drawings, it is to be understood that the invention is not limited to those
precise embodiments, and that various changes and modifications may be effected therein
by one skilled in the art without departing from the scope or spirit of the invention as
2 o defined in the appended claims.
