WO2001038788A1

WO2001038788A1 - Stack structure

Info

Publication number: WO2001038788A1
Application number: PCT/JP2000/008146
Authority: WO
Inventors: Yoshikazu Kitano
Original assignee: Kabushiki Kaisha Maruki
Priority date: 1999-11-19
Filing date: 2000-11-17
Publication date: 2001-05-31
Also published as: CN1391642A

Abstract

A stack structure capable of preventing carbon dioxide causing global warming from being exhausted into the atmosphere, wherein: a porous stack is disposed in a pipe body having a base end communicating with a combustion chamber, a tip end with an exhaust gas port provided thereto, and a combustion gas flow path formed therein; or the pipe body is formed by bending it in an inverted U-shape, and a porous stack is disposed in the combustion gas flow path.

Description

Description Chimney structure Technical field

TECHNICAL FIELD The present invention relates to a chimney structure capable of halving the height of a chimney and removing harmful carbon dioxide from combustion gas. Background art

Conventionally, refuse incineration plants and the like often have tall chimneys of several tens of meters.

This is intended to spread over the sky so that dust and other harmful substances scattered from the chimney and other harmful substances do not affect nearby areas, and it consumes enormous construction costs.

However, in recent years, environmental pollution due to exhaust gas from chimneys and the like has become a problem on a global scale, and various studies are being advanced.

Above all, research and development on countermeasures against daisy toxins generated by garbage incineration have progressed relatively, and incinerators that can greatly reduce the occurrence of daisy toxins have been developed.

However, carbon dioxide (co ₂ ) contained in the exhaust gas from the chimney is almost completely ignored.

Carbon dioxide itself is also a major component of the atmosphere, and has not been a problem since it did not have a direct adverse effect on the human body as did Daidai Toxin and other harmful substances. Carbon dioxide is rapidly increasing and is facing a very serious problem of global warming.

However, it is difficult to change human lifestyles and production systems significantly, and it is impossible to incinerate garbage or provide all energy without generating carbon dioxide. Therefore, all means must be taken to reduce atmospheric carbon dioxide. Disclosure of the invention

Therefore, in order to solve the above problem, in the present invention according to claim 1, a porous stack is provided in a pipe having a base end communicating with a combustion chamber and an exhaust gas port provided at a front end to form a combustion gas flow path. It was arranged. Therefore, with such a stack, a dream pipe effect accompanied by heat transport is produced, the temperature of the chimney outlet can be significantly reduced, and secondary generation of dioxin can be prevented. Therefore, it can be used for small incinerators and the like, and even for large incinerators, the height of the chimney to be constructed can be reduced and the construction cost can be reduced.

According to the second aspect of the present invention, the pipe is bent in an inverted U-shape, and a porous stack is disposed in a combustion gas flow path formed in the pipe. Therefore, the height of the chimney can be made lower, and even if the exhaust gas outlet is close to the surface of the ground, the stack also has a dream pipe effect with heat transport due to the arrangement of the stack. Can be significantly reduced, and there is no danger of the adverse effects of smoke and high-gas.

According to the third aspect of the present invention, the base end of the inner cylindrical body having an open upper end is communicated with the combustion chamber, and the upper end is closed so as to include the inner cylindrical body, and the exhaust gas port is formed in the middle of the cylindrical body. The formed outer cylinder is disposed, and a combustion gas flow path is formed by communicating a tubular flow path inside the inner cylinder with an annular flow path formed between the inner cylinder and the outer cylinder. A porous stack was installed in the combustion gas channel. Therefore, the chimney to be constructed has a double structure that can reduce the height by half while securing the required length of the exhaust gas flow path, and can reduce the height and the construction cost. In addition, the arrangement of the stack produces a dream pipe effect accompanied by heat transport, which can significantly reduce the temperature of the smoke outlet. There is no risk of adverse effects due to gas. In addition, regarding the sound derived from the dream pipe effect, a double pipe structure consisting of a tubular flow path and an annular flow path is used. The frequency of the generated sound can be canceled out, and silence can be achieved.

According to the fourth aspect of the present invention, a filter is provided in the combustion gas flow path. Therefore, soot and dust can be adsorbed, and clean exhaust gas can be obtained.

According to the fifth aspect of the present invention, the exhaust gas device is connected to the exhaust gas processing means. Therefore, there is no need to worry about environmental pollution because the exhaust gas is clean.

In the present invention according to claim 6, a blower is provided in the exhaust gas port. Therefore, the exhaust gas from the combustion chamber can be efficiently guided to the exhaust gas treatment means.

According to the present invention, the sock is formed of a porous ceramic. Therefore, the existing material can be used as the stack, and the stack can be easily obtained, and the dream pipe effect can be further enhanced.

In the present invention according to claim 8, the exhaust gas treating means is a gas generating unit that generates a methane gas by causing a reduction reaction of carbon dioxide with water using a photocatalyst. Therefore, by replacing this with methane gas without emitting carbon dioxide into the atmosphere, it can be effectively used as an external energy source such as a power source or a heat source.

In the present invention according to claim 9, the gas generating unit includes: a combustion gas storage chamber; a water tank connected to the combustion gas storage chamber; and a methane gas purification chamber connected to the water tank. A photocatalyst in which palladium was supported on the surface of titanium oxide was dispersed in the part. In other words, by using a solid-state semiconductor photocatalyst that can utilize water as a reducing agent and that can accumulate multiple electrons, carbon dioxide can be efficiently reduced, and the efficiency of producing menthane gas can be improved.

According to the tenth aspect of the present invention, the exhaust gas treatment means is a carbon dioxide recovery tank containing a processing solution in which calcium hydroxide is dissolved, and the carbon dioxide contained in the combustion gas can be recovered as calcium carbonate. did. Therefore, carbon dioxide generated by combustion can be recovered in a stable state.

According to the present invention, the inside of the carbon dioxide recovery tank is maintained at a negative pressure. Therefore, the combustion gas can be effectively drawn into the carbon dioxide capture tank. In the present invention according to claim 12, the exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and generates the separated carbon dioxide and a hydrogen generator. By reacting with hydrogen, methanol could be produced. Therefore, by replacing methanol with methanol without emitting carbon dioxide to the atmosphere, it can be effectively used as an external energy source such as a power source or a heat source.o

In the present invention according to claim 13, the exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and generates the separated carbon dioxide and the hydrogen from the hydrogen generator. By reacting with hydrogen, carbon could be generated. Therefore, it can be replaced with pure carbon as a resource without emitting carbon dioxide into the atmosphere.

According to the present invention, a cooling circuit for cooling the surface of the stack is provided. Therefore, the exhaust gas temperature can be efficiently reduced. BRIEF DESCRIPTION OF THE FIGURES

【Figure 1】

FIG. 2 is a schematic explanatory view of a chimney structure according to the first embodiment.

【Figure 2】

FIG. 8 is a schematic explanatory view of a chimney structure according to a second embodiment.

[Figure 3]

It is explanatory drawing which shows the modification of the exhaust gas processing means in the embodiment.

[Fig. 4]

FIG. 9 is a schematic explanatory view of a chimney structure according to a third embodiment.

[Figure 5]

[Fig. 6]

FIG. 9 is a schematic explanatory view of a chimney structure according to a fourth embodiment.

[Fig. 7] FIG. 8 is an explanatory view showing a modified example of the exhaust gas processing means in the embodiment c.

[Fig. 9]

FIG. 14 is a schematic explanatory view of a chimney structure according to a fifth embodiment.

[Fig. 10]

FIG. 4 is an explanatory diagram of a stack cooling unit. BEST MODE FOR CARRYING OUT THE INVENTION

As one mode of the chimney structure according to the present invention, a porous stack is disposed in a pipe in which a base end communicates with a combustion chamber, an exhaust gas port is provided at a tip end, and a combustion gas flow path is formed. Can be. The tube may have an upright structure or a slightly inclined structure.

In other words, by arranging a porous stack inside the pipe, the high-grade exhaust gas can be cooled down to about room temperature near the smoke outlet by the dream pipe effect, and the secondary daisy toxin is generated. That is to prevent that. In addition, soot and dust can be captured by the stack.

Therefore, the chimney can be made relatively low, and the construction cost can be greatly reduced.

Further, such a structure can be adopted for a small incinerator or the like, and can be easily installed in a school or other facilities.

Further, the above-mentioned tubular body may be bent in an inverted U-shape, and the porous stack described above may be disposed in a combustion gas flow passage formed in the tubular body.

In other words, the concept of the chimney, which was standing upright, was broken, and the chimney pipe was bent downward in the middle to form an inverted U-shape, and a porous stack placed inside the pipe was used. The dream pipe effect enables high-temperature exhaust gas to be cooled down to about room temperature, and enables soot and dust to be captured by the stack. Therefore, a chimney with a shorter height can be provided, and the tip portion serving as an exhaust gas outlet Will also be located near the ground, which will significantly reduce construction costs, for example, in garbage incineration plants.

By the way, the above-mentioned stack can be formed of porous ceramics. In other words, existing materials such as a catalyst disposed in an exhaust pipe of an automobile can be used as a sock, so that the material can be easily obtained and the dream pipe effect can be further enhanced.

Further, the above-mentioned tubular body may be bent in an inverted U-shape, and the porous stack described above may be provided in a combustion gas flow path formed in the tubular body. If this chimney structure is bent in a U-shape, the height of the chimney can be further reduced.In addition, since the tip, which is the exhaust gas outlet, is also located near the ground, construction costs can be reduced. It can be greatly reduced.

By the way, a configuration having a cooling circuit for cooling the surface of the stack may be employed. Such a rejection circuit allows the exhaust gas temperature to be reduced more efficiently.Furthermore, the exhaust gas can be communicated with the exhaust gas treatment means, and the harmful substances contained in the exhaust gas are removed and then discharged to the atmosphere. You can also. At this time, if the temperature of the exhaust gas at the inlet of the exhaust gas treatment means is as high as about 300 ° C, it is reported that a large amount of dioxin is generated in the treatment means. According to Ming, it will also be effective in controlling daisies.

In addition, a special filter for soot and dust as well as a stack can be provided in the pipe. The placement location may be located at either the top or bottom of the stack or at both locations as required.

In addition, if the combustion chamber is configured to be capable of high-temperature combustion at 1000 to 1500 ° C, it is possible to remove dioxin, which has recently become a problem, in the combustion chamber. Further, a blower can be provided in the exhaust gas port. That is, the exhaust gas from the combustion chamber is forcibly sucked by the blower and can be efficiently guided to the exhaust gas treatment means.

In addition, the present invention particularly provides carbon dioxide, which causes global warming, to the atmosphere. Since it also has the purpose of preventing discharge, the exhaust gas treatment means can have the following configuration.

That is, the exhaust gas processing means is a gas generating unit that generates a methane gas by causing a reduction reaction of carbon dioxide with water using a photocatalyst.

In particular, the gas generating section includes a combustion gas storage chamber, a water tank communicating with the combustion gas storage chamber, and a methane gas purification chamber communicating with the water tank. If a photocatalyst carrying palladium on the surface is dispersed, water can be used as a reducing agent and a solid-state photocatalyst capable of accumulating multiple electrons can be used to efficiently reduce carbon dioxide. It can be reduced and the efficiency of menthol gas generation can be improved.

As described above, according to the present invention, carbon dioxide can be effectively used as an external energy source such as a power source or a heat source by replacing it with methane gas without discharging carbon dioxide into the atmosphere.

As explained above, the chimney to be constructed is short, which can reduce construction costs and eliminate the concern of environmental pollution. Also, since the temperature of the smoke outlet can be greatly reduced, there is no danger of soot or high-grade gas even if the exhaust gas outlet is close to the ground. The above-mentioned dream pipe effect has been analyzed by thermoacoustic theory, which has been studied in recent years.

Further, as another preferred embodiment of the exhaust gas treatment means, the following constitution can be adopted.

That is, the exhaust gas treatment means is a carbon dioxide recovery tank containing a treatment solution in which calcium hydroxide is dissolved, and carbon dioxide contained in the combustion gas can be recovered as carbon dioxide.

Carbon dioxide is known to react with calcium hydroxide to form calcium carbonate and water. Calcium carbonate acts as a reservoir for carbon dioxide and exists naturally in a stable form as calcite.

Therefore, the carbon dioxide generated by combustion can be recovered in a stable state without being released to the atmosphere. In general, it is often attached desulfurization apparatus in the combustion chamber, calcium carbonate, which can be used as an absorbent for use in the desulfurization apparatus, in this case, it is reacted with SO _x in the exhaust gas Plaster can also be obtained as a by-product.

When calcium hydroxide (slaked lime) is dissolved in water, it is known that a lower temperature is preferable. However, as described above, the exhaust gas temperature is greatly reduced by the dream pipe effect. It is possible to ensure the required amount of calcium hydroxide dissolved in the liquid.

Further, a plurality of such carbon dioxide recovery tanks can be provided in series as needed.

Further, it is preferable that the inside of the carbon dioxide recovery tank is maintained at a negative pressure, and the combustion gas from the combustion chamber passing through the inverted U-shaped pipe is effectively drawn in even if the above-mentioned blower device or the like is not particularly provided. be able to.

Further, as another form of the exhaust gas treatment means, the exhausted gas is separated into nitrogen and carbon dioxide through the decomposition catalyst of ΝΟχ, and the separated carbon dioxide and hydrogen generated from the hydrogen generator are separated. It can be reacted to produce a methyl alcohol.

Furthermore, as an exhaust gas treatment means, the exhaust gas is separated into nitrogen and carbon dioxide via the decomposition catalyst of ΝΟχ, and the separated carbon dioxide reacts with the hydrogen generated from the hydrogen generator to produce carbon. Can be generated.

According to such a configuration, it is possible to recover carbon dioxide as a pure resource instead of carbon as a pure resource without emitting carbon dioxide to the atmosphere, and to utilize the carbon dioxide effectively. Further, as a further embodiment of the chimney structure according to the present invention, a base end of an inner cylindrical body having an open upper end is communicated with the combustion chamber, and the upper end is closed so as to include the inner cylindrical body. An outer cylinder having an exhaust slot formed in the middle thereof is provided, and a tubular channel inside the inner cylinder communicates with an annular channel formed between the inner cylinder and the outer cylinder. Alternatively, a combustion gas flow path may be formed to form a porous stack in the combustion gas flow path.

Even with this structure, the height of the exhaust gas passage can be reduced by almost half while securing the required length, and the chimney to be constructed is shorter and the construction cost is reduced. Can be In addition, in this case, a vertical chimney structure can be used, so that even a large chimney can be installed in a small space.

Also in this case, the stack described above can be provided, and by providing such a stack, a dream pipe effect accompanied by heat transport is exhibited, and the temperature at the chimney outlet is significantly reduced. Even if the exhaust gas outlet is located as low as possible near the surface of the ground, there is no risk of adverse effects from soot and high-gas.

Further, as described above, by connecting the exhaust gas outlet of the chimney to the exhaust gas treatment means, it is possible to prevent the emission of carbon dioxide, which causes global warming, into the atmosphere.

In addition, the chimney structure of the present embodiment has a characteristic double structure of the inner cylinder and the outer cylinder, so that the noise generated due to the above-described dream pipe effect is reduced by the tubular flow path of the inner cylinder, The noise generated from the annular flow path formed between the inner cylinder and the outer cylinder interferes with each other, and the frequencies are offset, so that noise can be greatly reduced and the surrounding environment can be disturbed. Absent.

Hereinafter, more specific embodiments of the present invention will be described with reference to the drawings.

(First embodiment)

FIG. 1 is a schematic explanatory view showing a chimney structure according to the first embodiment.

In the figure, reference numeral 1 denotes a combustion chamber of a refuse incinerator, which includes a first combustion chamber 11 as an incinerator for directly charging a substance to be burned, a second combustion chamber 12, which performs the most combustion in two stages, and a third combustion chamber. The combustion chamber is divided into chambers 13, and the combustion temperature is controlled in each of the combustion chambers 11, 12, 13, so that generation of harmful substances is suppressed as much as possible. In the figure, reference numeral 14 denotes a burner device provided in each of the combustion chambers 11, 12, and 13, and reference numeral 15 denotes a communication path connecting the first combustion chamber 11 and the second combustion chamber 12.

Reference numeral 3 denotes a chimney which is a main part of the present invention.The stack 30 has a base 30a communicating with the combustion chamber 1 and a discharge gas slot 30b provided at the end to form a combustion gas flow path R, and a porous stack is provided therein. The feature is that 4 are arranged.

That is, the base end 30a of the pipe 30 is connected to the third combustion chamber 13 so as to extend directly upward, and the outlet 30b is positioned at a height h from the parner device 14 of the third combustion chamber 13. . A plurality of porous stacks 4 are arranged inside the pipe 30 at appropriate intervals, and the combustion gas discharged from the combustion chamber 1 is passed through the pipe 30 through the stack 4. I have.

Therefore, due to the dream pipe effect of the stack 4, the exhaust gas rising from the lower part of the pipe 30 at a high temperature is greatly cooled to near normal temperature in the vicinity of the discharge port 30 b, and secondary generation of dioxin is generated. Can be prevented. The stack 4 is made of porous ceramics used as an exhaust gas treatment catalyst in an exhaust pipe of an automobile and molded into a shape that can be disposed inside the chimney 3. The number and position of the stacks 4 may be determined by experimentally finding the optimum number and the optimum position.In the present embodiment, three stacks 4 are connected to the third combustion chamber 13. It is arranged at a distance of h / 4 from the banner device 14.

The above-mentioned chimney structure can be used for both large refuse incinerators and small incinerators that can be used in schools and homes. A chimney suitable for reduced environmental protection can be provided.

Although the above-mentioned pipe 30 is made upright, it may be slightly inclined, especially in the case of a small chimney.

(Second embodiment)

FIG. 2 is a schematic explanatory view showing a chimney structure according to the second embodiment. In the figure, 1 is a combustion chamber of a refuse incinerator, to which a desulfurization unit 2 is attached. The combustion chamber 1 according to the present embodiment is configured to be capable of burning at a high temperature of about 125 ° C. to about 150 ° C. in order to suppress the generation of dyes. Although not shown, a sub-combustion chamber may be provided to suppress combustion at around 800 ° C in combustion chamber 1 and burn at high temperature in the sub-combustion chamber to convert incinerated ash and fly ash into molten slag. .

In the above configuration, the feature of the present embodiment is that the pipe 30 of the chimney 3 is extended upward and is bent in the middle in a substantially inverted U-shape to form a substantially inverted U-shaped pipe. That is, the porous stack 4 described above is disposed in the middle of the first vertical portion 31 and the second vertical portion 32 of the device 30, respectively.

The exhaust gas port 30b, which is located at a height close to the ground, is connected to an exhaust gas treatment It communicates with the steps. In the figure, 31 is a first vertical portion, 32 is a second vertical portion, and .33 is a bent portion. In the present embodiment, the height of the inverted U-shaped portion of the chimney 3 is about 15 m.

In addition, the arrangement position of each stack 4 may be determined by experimentally finding the optimum position. In this embodiment, the height position H of the stack 4 arranged in the first vertical portion 31 is determined based on the height position H. Position 3 to 8 m from the position of end 3 Oa, Arrangement position D of stack 4 to be arranged in second vertical portion 32 is set to 3 to 8 m from the upper end of bent portion 33 .

Further, in the second vertical portion 32, a filter 5 for removing dust and ash is provided on the lower side of the stack 4. The location of the filter 5 and the number of the filters 5 may be determined as appropriate, and are not particularly limited to the present embodiment.

With the above-described configuration of the chimney structure, the combustion gas discharged from the combustion chamber 1 passes through the inverted U-shaped pipe 30 while passing through the stack 4 and the filter 5, and the dream pipe formed by the stack 4 Due to the effect, the temperature is reduced to nearly the normal temperature. As described above, since the exhaust gas concentration at the entrance of the exhaust gas treatment means is lowered, it is possible to prevent the secondary production of daisy toxin and the like in the exhaust gas treatment means.

In addition, the stack 4 and the filter 5 allow the exhaust gas subjected to the primary treatment from which soot and dust has been removed to flow into the exhaust gas processing means, thereby reducing the processing load of the exhaust gas processing means. In particular, when silver or silver oxide is carried on the stack 4, the primary treatment effect of the exhaust gas can be further enhanced.

Here, the configuration of the exhaust gas processing means in the present embodiment will be described.

Exhaust gas treatment means, other removal of harmful substances die old Xing, in particular, for the purpose of carbon dioxide that causes global warming (C 0 ₂₎ is prevented from being discharged into the atmosphere For this purpose, the gas generating unit 6 functions as a gas generating unit 6 that generates a methane gas by inducing a reduction reaction of carbon dioxide with water using a photocatalyst. A chamber 60, a water tank 61 communicating with the combustion gas storage chamber 60, and a methane gas purification chamber 62 communicating with the water tank 61. A photocatalyst 63 in which palladium is supported on the surface of titanium oxide is dispersed in the water tank 61. 62a is a methane gas outlet.

Since the photocatalyst 63 is a solid-state photocatalyst capable of accumulating multiple electrons, water can be used as a reducing agent as shown in the following formula, and carbon dioxide can be efficiently reduced to improve the menthol gas generation efficiency. Can be done. The following shows the reaction formula for producing methane gas by reduction of carbon dioxide.

C 0 ₂ + 8 e— + 2 H + → CH ₄ + 2 H ₂₀

The generated methane gas can be effectively used as power generation and heating energy.

As described above, according to the present embodiment, a large amount of carbon dioxide is not emitted into the atmosphere, which can greatly contribute to the prevention of global warming, and the carbon dioxide generated by combustion is converted into methane gas. By replacing it, energy can be effectively used as an external energy source such as a power source or a heat source, and energy can be saved.

FIG. 3 shows a modified example of the exhaust gas treatment means for obtaining methane gas from the generated carbon dioxide.

That is, the exhaust gas treatment flow path S which communicatively connected to the chimney 3, V ₂ 0 ₅ - together with Ti 0 ₂ provided catalyst chamber 65 where the cracking catalyst accommodated in the NOx such as, downstream thereof, carbon dioxide and nitrogen Liquefaction tank T1 that liquefies and separates gas, reaction tank T2 that vaporizes carbon dioxide and reacts with hydrogen, and gas tank T3 that stores methane gas generated by the reaction between carbon dioxide and hydrogen are arranged in series are doing. V1 is a drain drain.

In reaction tank T2, Fe, Ru, Ni -Al 2 0 3, Si and the like as a catalyst, methane gas is generated by the following reaction.

C〇 ₂ + 4 H ₂ → CH ₄ + 2 H ₂ 0

In addition, the temperature and pressure in the reaction tank T2 are appropriately set depending on the catalyst used.

Reference numeral 66 denotes a reducing agent tank that accommodates urea water as a reducing agent and allows the urea water to be sprayed into the exhaust gas treatment flow path S via a relevance 66v, and is disposed on the upstream side of the catalyst chamber 65. ing. Reference numeral 67 denotes a nitrogen separation tank connected to and connected to the liquefaction tank T1. , 67V is a liquid nitrogen discharge valve, and 68 is a hydrogen generation unit which is connected to the reaction tank T2 via a valve V2. In the hydrogen generating section 68, water is electrolyzed or hydrogen is obtained by a reaction between water and a metal.

In addition, the flow path on the lower side of the catalyst chamber 65 and the liquefaction tank T1 maintain the temperature at 31 ° C. or less and the pressure at 72.8 atm.

In the above configuration, although not shown, a blower for forcibly drawing the exhaust gas from the chimney 3 into the exhaust gas treatment channel S is provided at a connection portion between the chimney 3 and the exhaust gas treatment channel S.

(Third embodiment)

Next, a third embodiment of the present invention will be described with reference to FIG. This is the configuration of the smoke collision 3 is common to the second embodiment, the exhaust gas treatment unit is obtained by enabling recovery of carbon dioxide contained in the exhaust gas as calcium carbonate (C a C 0 ₃₎ .

That is, as shown in FIG. 4, the exhaust gas treatment means in the present embodiment is a carbon dioxide recovery tank 7 containing a treatment liquid 70 in which hydroxylic acid (slaked lime) is dissolved, and the carbon dioxide contained in the exhaust gas. Can be recovered as calcium carbonate (C a C〇 ₃ ).

It is known that carbon dioxide reacts with calcium hydroxide to form calcium carbonate and water as shown by the following formula.

C〇 ₂ + C a (OH) ₂ → C a C 0 ₃ + H ₂ 〇

Calcium carbonate plays a role as a store of carbon dioxide on the earth, and naturally exists as calcite in a stable form.

Therefore, according to this embodiment, the carbon dioxide generated by the combustion can be recovered in a stable state without being discharged to the atmosphere.

In particular, since the combustion chamber 1 is provided with the desulfurization device 2, calcium carbonate can be reused as an absorbent used in the desulfurization device 2. When carbonated calcium is used, gypsum can be obtained as a by-product by reacting with SO _{x in} the exhaust gas. Also, it is known that when calcium hydroxide is dissolved in water, a lower temperature is preferable.In this embodiment, too, the chimney 3 has a significantly lower exhaust gas temperature due to the dream pipe effect. The required amount of calcium hydroxide dissolved in the treatment liquid 70 can be secured without increasing the temperature of the treatment liquid 70 in the carbon dioxide recovery tank 7.

Further, it is preferable that the inside of the carbon dioxide recovery tank 7 is maintained at a negative pressure, so that the exhaust gas from the combustion chamber 1 passing through the inverted U-shaped pipe 30 can be effectively drawn in without a blower device or the like. it can. In the figure, P is a vacuum pump provided to make the inside of the carbon dioxide capture tank 7 a negative pressure, and is provided in the middle of an exhaust pipe 71 extending from the ceiling wall of the carbon dioxide capture tank 7. Reference numeral 72 denotes a calcium carbonate outlet formed on the bottom wall of the carbon dioxide recovery tank 7, and reference numeral 73 denotes an open / close valve connected to the outlet 72. Further, as shown by the alternate long and short dash line a in FIG. 4, a plurality of such carbon dioxide collecting tanks 7 can be provided in series according to the amount of treatment. In this case, the end of the exhaust pipe 71 may be extended, and inserted deep into the second tank 7 'for connection.

Further, as shown in FIG. 4, on the lower side of the combustion chamber 1, there may be provided a die-cut xin treatment chamber 8 using supercritical water.

Supercritical water is obtained by applying a certain pressure to water and applying a certain temperature to the boundary between the liquid and the gas. It is known to decompose and detoxify.

The chimney structure according to the third embodiment is as described above. In this embodiment, as in the first and second embodiments, a large amount of carbon dioxide is not emitted into the atmosphere, which is great for preventing global warming. <Can contribute.

FIG. 5 shows a modification of the exhaust gas treatment means in the third embodiment.

That is, the configuration shown in Fig. 3 is applied between the chimney 3 and the carbon dioxide recovery tank 7, and carbon dioxide is separated and extracted from the exhaust gas, and is introduced into the treatment liquid 70 to be stable. Calcium carbonate is recovered. Therefore, the nitrogen component in the exhaust gas is not introduced into the carbon dioxide recovery tank 7, and the carbon dioxide can be efficiently converted into calcium carbonate. (Fourth embodiment)

Next, a fourth embodiment of the present invention will be described with reference to FIG. This is characterized by the structure of the chimney 3. In the first embodiment, the pipe 30 is made upright as a single body, and in the second and third embodiments, the inverted U-shaped pipe 30 is formed into an upright shape having a double cylindrical structure. It is composed. The configuration of the exhaust gas treatment means connected to the chimney 3 may be any of those shown in the second and third embodiments described above, and may be the configuration described later. Others may be adopted.

Further, as in the first embodiment, the combustion chamber 1 in the present embodiment includes a first combustion chamber 11 as an incinerator for directly injecting a substance to be burned, and a second combustion chamber for performing the most combustion in two stages thereafter. 12 and the third combustion chamber 13.

The chimney 3 in this embodiment connected to the combustion chamber 1 described above communicates with the combustion chamber 1 through a base end 35b of an inner cylindrical body 35 having an open upper end 35a, and includes the inner cylindrical body 35. An outer cylinder 36 having an upper end closed and an exhaust gas port 36a formed in the middle of the cylinder is disposed, and the inner cylinder 35 and the outer cylinder 36 are formed from the tubular flow path R1 inside the inner cylinder 35. The combustion gas flow path R is formed by communicating with the annular flow path R2 formed therebetween, and the porous stack 4 is disposed in the combustion gas flow path R.

Further, an exhaust gas port 36a formed in the outer cylindrical body 36 is connected to the exhaust gas processing means as described in the first and second embodiments. 36b is the closed upper end of the outer cylinder 36. Reference numeral 5 denotes a filter disposed on the lower side of the stack 4.

Further, the shape of the stack 4 and the filter 5 is formed into a cylindrical shape or a donut shape, respectively, according to the shape of the tubular flow path R1 or the annular shape R2.

With the above-described configuration, also in this embodiment, the arrangement of the stack 4 in the combustion gas flow path R produces a dream pipe effect accompanied by heat transport, and the smoke outlet temperature, that is, the outer cylindrical body The temperature downstream from the 36 exhaust gas ports 36a can be greatly reduced, and even if the exhaust gas ports 36a are located as low as possible near the surface of the earth, there is no danger of adverse effects due to soot and high-temperature gas.

Moreover, the stack 4 is disposed as a double-structured upright type comprising the inner cylinder 35 and the outer cylinder 36 without bending the chimney 3 as in the first and second embodiments, and combustion is performed. The height of the chimney 3 can be reduced by almost half with respect to the length of the flow path R while securing the length of the combustion gas flow path R necessary for lowering the temperature of the gas.

Also, since it can be an upright type, there is no need to unnecessarily increase the installation space.

Further, the chimney 3 has a characteristic double pipe structure of the inner cylinder 35 and the outer cylinder 36, thereby providing a calming effect.

That is, with respect to the noise generated due to the dream pipe effect, the double pipe structure causes the sounds generated from the tubular flow path and the annular flow path to interfere with each other, canceling out the frequencies, and greatly reducing the noise. That can be reduced. Therefore, with the chimney structure according to the present embodiment, there is no risk of disturbing the environment around the installation.

By the way, the number of the stacks 4 to be arranged and their intervals and arrangement positions can be appropriately set from the length of the combustion gas flow path R. By determining the number and arrangement of the stacks 4, the height position of the exhaust gas port 36a communicating with the exhaust gas treatment means can be set freely. Therefore, even when constructing equipment that will be used as an exhaust gas treatment device after installing the chimney 3, it is necessary to provide the exhaust gas port 36a at the optimum position in consideration of the installation conditions of the equipment and the installation conditions of the combustion chamber 1. It becomes possible.

As described above, the chimney structure in this embodiment can reduce the height of the chimney 3 and can be installed in a small space, thereby reducing construction costs and quieting expected noise. Can be

Also, in this embodiment, as in the first and second embodiments, by communicating and connecting with the exhaust gas treatment means, it is possible to prevent carbon dioxide, which causes global warming, from being discharged into the atmosphere. It is possible.

By the way, as the exhaust gas treatment means, in addition to those described above, those having the configurations shown in FIGS. 7 and 8 can be adopted.

That is, the exhaust gas treatment means shown in FIGS. 7 and 8 can generate methanol from carbon dioxide in exhaust gas.

The one shown in FIG. 7 basically has the configuration shown in FIG. During, V ₂ 0 with ₆ -Ti 0 ₂ provided catalyst chamber 65 where the cracking catalyst accommodated in the NOx such as, downstream thereof, to vaporize the liquefied tank Ή for liquefying separation of carbon dioxide and nitrogen, carbon dioxide A reaction tank T2 for reacting hydrogen with hydrogen and a methanol tank T4 for containing methanol generated by the reaction between carbon dioxide and hydrogen are arranged in series. V3 is a methanol extraction valve.

With the above configuration, methane gas is generated in the reaction tank T2 by the following reaction.

C 0 ₂ + 3 H ₂ → CH ₄ + CH ₃ 0 H + H ₂₀

As a matter of course, an appropriate catalyst is used, and the temperature and pressure in the reaction tank T2 are appropriately set according to the catalyst used.

In addition, the one shown in FIG. 8 further separates carbon dioxide generated by the configuration shown in FIG. 7 into carbon monoxide and water, and reacts the obtained carbon monoxide with hydrogen to produce methanol. I'm trying to get.

That is, to obtain a methanol by reaction of _{_{CO + 2 H 2 → CH 3}} OH. Also in this case, the catalyst should be selected appropriately, and the temperature and pressure conditions should be set appropriately. In the figure, T5 is a carbon monoxide tank, which is connected to the hydrogen generator 68 via a valve V2 '.

(Fifth embodiment)

FIG. 9 shows a configuration in which pure exhaust gas is obtained by means of an exhaust gas treatment means, and is basically configured as shown in FIG. B is a blower that forcibly draws exhaust gas from chimney 3 into exhaust gas treatment channel S.

That is, the exhaust gas treatment flow path S which communicatively connected to the chimney 3, V ₂ 0 ₅ - together with Ti 0 ₂ provided catalyst chamber 65 where the cracking catalyst accommodated in the NOx such as, downstream thereof, carbon dioxide and nitrogen A liquefaction tank T1 for liquefaction and separation of carbon dioxide, a reaction tank T2 for vaporizing carbon dioxide and reacting with hydrogen, and a carbon tank T6 for containing carbon generated by the reaction between carbon dioxide and hydrogen are arranged in series. ing.

Then, a reaction of C 0 ₂ +2 H ₂ → C + 2 H ₂ 0 is performed to obtain a force. In this case, too, the catalyst is appropriately selected, The temperature and pressure conditions are set appropriately.

Further, in this embodiment, the chimney 3 has a double pipe structure composed of an inner cylindrical body 35 and an outer cylindrical body 36 as in the fourth embodiment, and the stack 4 is used as a stack cooling means for forcing; ; Rejection circuit F is provided.

As shown in FIG. 10, the cooling circuit F includes a cooling tank F1 having a pump for storing cooling water and being capable of forcibly circulating, and a piping portion F2 forming a circulation flow path. As the pipe to be used, it is preferable to use a member having a high thermal conductivity. In this embodiment, a copper pipe is used.

Then, the middle of the pipe portion F2 is formed so as to spirally contact the surface of the stack 4. F2 'is a contact part.

Further, a high heat conductivity material such as a copper plate can be interposed between the contact portion F2 'and the stack 4.

In the present embodiment, the cooling tank F1 is provided outside the chimney 3, but in order to improve the external appearance, the cooling tank F1 is configured to be sufficiently insulated, and the inner cylinder 35 and the outer cylinder It may be arranged between the body 36, that is, inside the chimney 3.

As described above, the present invention has been described through the above embodiments.For example, exhaust gas treatment means and the like do not necessarily need to be installed, and the configuration is not necessarily limited to the above embodiments. Absent.

Further, the cooling circuit F that forcibly rejects the stack 4 described above can also be applied to the above-described first to fourth embodiments. Industrial applicability

The present invention is implemented in the form as described above, and has the following effects.

(1) In the present invention according to claim 1, the porous stack is disposed in a pipe in which the base end communicates with the combustion chamber, the exhaust gas port is provided at the front end, and the combustion gas flow path is formed. In addition, a dream pipe effect accompanied by heat transport can be achieved, the chimney exit angle can be greatly reduced, and secondary production of daisy toxin can be prevented. But Therefore, it can be suitably used for small incinerators, etc., and even for large incinerators, the height of the chimney to be constructed can be reduced and the construction cost can be reduced.o

(2) In the present invention described in claim 2, the pipe body is bent in an inverted U-shape, and a porous stack is disposed in a combustion gas flow path formed in the pipe body, so that the stack The construction cost can be reduced by lowering the construction cost, and even if the exhaust gas outlet is close to the surface of the ground, the stack arrangement also produces a dream pipe effect that involves heat transport. Can be significantly reduced, and there is no risk of adverse effects due to smoke and hot gases.

(3) According to the present invention as set forth in claim 3, the base end of the inner cylindrical body having an open upper end is communicated with the combustion chamber, and the upper end is closed so that the inner cylindrical body is included. An outer cylinder forming an exhaust gas port is provided, and a combustion gas flow is formed by communicating a tubular channel inside the inner cylinder with an annular channel formed between the inner cylinder and the outer cylinder. By forming a channel and arranging a porous stack in the combustion gas flow path, the chimney to be constructed has a double length that can reduce the height by half while ensuring the required length of the exhaust gas flow path Since it has a tube structure, it is short and can be constructed in a small space, construction costs can be reduced. In addition, the arrangement of the stack produces a dream pipe effect accompanied by heat transport, so that the temperature of the smoke outlet can be greatly reduced. There is no fear. In addition, the noise generated by the dream pipe effect can be eliminated because of the double pipe structure.

(4) According to the present invention, since a filter is provided in the combustion gas flow path, soot, dust and the like can be adsorbed, and clean exhaust gas can be obtained.

(5) In the present invention described in claim 5, since the exhaust gas port is connected to the exhaust gas processing means, the exhaust gas is clean, so that there is no concern about environmental pollution.

(6) According to the present invention, by providing a blower at the exhaust gas port, the exhaust gas from the combustion chamber can be more efficiently guided to the exhaust gas treatment means.

(7) In the present invention described in claim 7, since the above-mentioned stack is formed of porous ceramic, existing materials can be used as the stack, which facilitates the acquisition. Cost can be reduced, and the dream pipe effect can be further enhanced.

(8) According to the present invention as set forth in claim 8, the exhaust gas treatment means is a gas generating unit that generates a methane gas by causing a reduction reaction of carbon dioxide with water using a photocatalyst, thereby reducing By replacing this with methane gas without emitting carbon dioxide to the outside, it can be effectively used as an external energy source such as a power source or heat source.

(9) In the present invention according to claim 9, the gas generating unit includes a combustion gas storage chamber, a water tank communicating with the combustion gas storage chamber, and a methane gas purification chamber communicating with the water tank. By dispersing a photocatalyst in which palladium is supported on the surface of titanium oxide in the water tank, water can be used as a reducing agent, and by using a solid-state semiconductor photocatalyst capable of accumulating multiple electrons, Carbon dioxide can be efficiently reduced, and the efficiency of menthol gas generation can be improved.

(10) In the present invention as set forth in claim 10, the exhaust gas treatment means is a carbon dioxide recovery tank containing a treatment liquid in which calcium hydroxide is dissolved, and the carbon dioxide contained in the combustion gas is calcium carbonate. By making it possible to recover, carbon dioxide generated by combustion can be recovered in a stable state.

(11) In the present invention described in claim 11, by maintaining the inside of the carbon dioxide recovery tank at a negative pressure, the combustion gas can be effectively drawn into the carbon dioxide capture tank, and the processing capacity can be increased. Can be.

(12) In the present invention as set forth in claim 12, the exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and separates the separated carbon dioxide and hydrogen By reacting with the hydrogen generated from the device to produce methanol, instead of emitting carbon dioxide to the atmosphere, it can be replaced with methanol to provide energy to external sources such as power sources and heat sources. Can be used effectively as a source

(13) In the present invention according to claim 13, the exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and separates the separated carbon dioxide and water. By making it possible to generate carbon by reacting with hydrogen generated from the element generator, it is possible to substitute carbon as a pure resource without discharging carbon dioxide into the atmosphere.

(14) In the present invention described in claim 14, the surface of the stack is cooled; since a rejection circuit is provided, the exhaust gas concentration can be reduced efficiently.

Claims

The scope of the claims

A chimney structure in which a porous stack is disposed inside a tube having a base end communicating with a combustion chamber and an exhaust gas port provided at a front end to form a combustion gas flow path. 2. The chimney structure according to claim 1, wherein the pipe is bent in an inverted U-shape, and a porous stack is disposed in a combustion gas flow path formed in the pipe. An outer cylinder with an upper end closed and an exhaust gas port formed in the middle of the cylinder is provided so that the base end of the inner cylinder with an open upper end communicates with the combustion chamber and the inner cylinder is included. And forming a combustion gas flow path by communicating from the tubular flow path inside the inner cylindrical body with an annular flow path formed between the inner cylindrical body and the outer cylindrical body. A chimney structure characterized by a porous stack. 4. The chimney structure according to claim 1, wherein a filter is provided in the combustion gas flow path.

The chimney structure according to any one of claims 1 to 4, wherein the exhaust gas is connected to the exhaust gas processing means. The chimney structure according to any one of claims 1 to 5, wherein a blower is provided in the exhaust gas port. The chimney structure according to any one of claims 1 to 6, wherein the stack is formed of a porous ceramic. The chimney structure according to any one of claims 5 to 7, wherein the exhaust gas treatment means is a gas generation unit that generates a methane gas by causing a reduction reaction of carbon dioxide with water using a photocatalyst. The gas generating unit includes a combustion gas storage chamber, a water tank communicating with the combustion gas storage chamber, and a methane gas purification chamber communicating with the water tank. In the water tank, palladium is supported on the surface of titanium oxide. 9. The chimney structure according to claim 8, wherein the carried photocatalyst is dispersed. The exhaust gas treatment means is a carbon dioxide recovery tank containing a treatment solution in which calcium hydroxide is dissolved, and carbon dioxide contained in the combustion gas can be recovered as carbon dioxide. The chimney structure according to any one of items 5 to 7. The chimney structure according to claim 10, wherein the inside of the carbon dioxide recovery tank is maintained at a negative pressure. The exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and reacts the separated carbon dioxide with the hydrogen generated from the hydrogen generator to produce methanol. The chimney structure according to any one of claims 5 to 7, wherein: The exhaust gas treatment means separates the exhausted gas into nitrogen and carbon dioxide via a NOx decomposition catalyst, and reacts the separated carbon dioxide with the hydrogen generated from the hydrogen generator to produce carbon. The chimney structure according to any one of claims 5 to 7, characterized in that: The chimney structure according to any one of claims 1 to 13, further comprising a cooling circuit for cooling a surface of the stack.