KR101224032B1 - Combustion apparatus - Google Patents

Abstract

This invention provides the combustion apparatus which can reduce the dust contained in combustion exhaust gas, and NOx or nitrous oxide. The combustion apparatus of one embodiment includes a furnace having a vertical double cylinder shape having an outer cylinder and an inner cylinder defining a combustion space, an upper burner for mixing and burning pyrolysis gas with primary combustion air in the combustion space, and a thermal decomposition at the upper burner. A gas supply line, a line supplying primary combustion air to the upper burner, and a lower portion than the upper burner, inject secondary combustion air to mix and burn unburned gas and the secondary combustion air in the combustion space. And a line for supplying secondary combustion air to the lower burner. The inner cylinder forms a flow path through which the lower end is opened to discharge combustion exhaust gas from the combustion space. The upper burner has a first combustion port that opens in the upper inner circumferential wall of the outer cylinder to inject the pyrolysis gas and the primary combustion air in the circumferential direction of the upper inner circumferential wall of the outer cylinder to form swirl flow in the combustion space.

Description

Combustion device {COMBUSTION APPARATUS}

This application is based on Japanese Patent Application No. 2010-20637 (Application date: February 1, 2010), which nominates a priority benefit from this application. This application includes the entire contents of this application by reference to this application.

Embodiments of the present invention relate to combustion apparatus used in waste treatment systems for treating organic waste.

In a waste treatment system for treating organic waste such as dewatered sludge, the organic waste is thermally decomposed to a low oxygen state in a pyrolysis furnace to discharge pyrolysis gas and pyrolysis residue. Since pyrolysis gas discharged from a pyrolysis furnace is flammable, pyrolysis gas is used as a heat source of a combustion apparatus.

Japanese Patent Publication No. 2007-270018 Japanese Patent Publication No. 2004-205161 Japanese Patent Publication No. 2006-207840

In the waste disposal system described in Japanese Patent Application Laid-Open No. 2007-270018, when ash is contained in the organic waste, there is not a lot of sold out when the organic waste is burned or thermally decomposed. As time goes by, the dust is attached to and deposited on the heat-use device, which lowers the heat transfer rate of the heat-use device. For this reason, the thermal efficiency of a heat utilization apparatus falls, respectively. In addition, when organic nitrogen is included in the organic waste, NOx, which is an air pollutant in the combustion exhaust gas, increases, or when the combustion temperature is low, nitrous oxide, which is a greenhouse gas, is generated.

The combustion apparatus described in Japanese Patent Laid-Open No. 2004-205161 or Japanese Patent Laid-Open No. 2006-207840 employs a two-stage combustion method as a method of reducing NOx, nitrous oxide, or unburned gas. However, these two stage combustion type combustion apparatuses cannot solve the problem that the dust is adhered to the inner wall of a heat utilizing apparatus or the like. For this reason, the method of mechanically removing the dust adhering to the inner wall of a heat utilization apparatus, etc. is used. Since the mechanical removal means of the sold out has a high facility cost and a maintenance cost, it leads to an increase in the cost of the entire system.

The technical problem to be solved by the present invention is to provide a combustion apparatus capable of reducing the amount of dust contained in the combustion exhaust gas discharged while reducing NOx, nitrous oxide, or unburned gas.

The combustion apparatus according to the embodiment is a combustion apparatus for combusting a flammable pyrolysis gas generated in a pyrolysis furnace of a waste treatment system for pyrolyzing organic waste, the outer cylinder defining a combustion space for combusting pyrolysis gas ( A furnace having a vertical double cylinder shape having an outer cylinder and an inner cylinder, the inner cylinder forming a flow path for discharging combustion exhaust gas from the combustion space; An upper burner injecting pyrolysis gas and primary combustion air into the combustion space to mix and burn the pyrolysis gas and the primary combustion air; A pyrolysis gas supply line for supplying a pyrolysis gas to the upper burner; A primary combustion air supply line for supplying primary combustion air to the upper burner; A lower burner disposed below the upper burner and injecting secondary combustion air into the combustion space to mix and combust unburned gas and secondary combustion air in the combustion space; A secondary combustion air supply line for supplying secondary combustion air to the lower burner; The upper burner has a first combustion port opening in the upper inner circumferential wall of the outer cylinder for injecting the pyrolysis gas and the primary combustion air in the circumferential direction of the upper inner circumferential wall of the outer cylinder.

According to the said structure, the amount of sold-out contained in the combustion exhaust gas discharged | emitted from a combustion apparatus can be reduced.

1 is a block diagram showing a waste treatment system having a combustion device according to a first embodiment;
2 (A) to 2 (D) are cross-sectional views each showing a two-stage burner in which the mounting position with respect to the outer cylinder is variously changed.
3 is an internal perspective schematic view showing a combustion device according to a second embodiment;
4 is an internal perspective schematic view of the combustion device according to the third embodiment;
Fig. 5 is a block diagram showing a waste treatment system having a combustion device according to the fourth embodiment.
6 is an internal perspective schematic view of the combustion device according to the fourth embodiment;
7 is a cross sectional view showing an example of a mounting position of a cooling air inlet pipe;

In the combustion apparatus of the embodiment, the furnace body of the two stage combustion system is vertical. By setting the furnace body to the double cylinder structure which consists of an outer cylinder and an inner cylinder, a vertical combustion space is formed. Moreover, the swirl flow of combustion exhaust gas arises in a combustion space by making the gas injection direction from the burner of the upper and lower stages 2 into a circumferential direction of the inner peripheral wall of an outer cylinder. When gas is injected from the burners of the upper and lower stages in such a vertical combustion space, a so-called spiral gas flow that forms while the combustion exhaust gas turns is formed. When centrifugal force acts on combustion exhaust gas, the dust which has a specific gravity larger than combustion exhaust gas flows in the periphery of a combustion space, is attached to the inner peripheral wall of an outer cylinder, and a dust is isolate | separated from combustion exhaust gas. By this centrifugal action, the dust is efficiently separated from the combustion exhaust gas. Therefore, according to the combustion apparatus of the embodiment, the amount of sold-out contained in combustion exhaust gas can be reduced. In addition, when the adhesion amount of the dust increases, the attached and deposited dust is peeled off from the inner circumferential wall by its own weight, and the peeled off dust is recovered from the lower part of the combustion apparatus. Sold out again on the inner circumferential wall after the sold-out peeled off, and when the adhesion amount of sold-out increases, it naturally peels off by its own weight and falls. As described above, according to the combustion apparatus of the embodiment, the dust is efficiently separated and recovered from the combustion exhaust gas by the cycle of adhesion → peeling down → adhesion of the dust in the combustion exhaust gas.

In the embodiment, it is preferable that the lower portion of the outer cylinder is formed in an inverted conical shape in which the diameter gradually decreases as it moves downward to increase the angular velocity of the combustion gas stream descending by rotating in the combustion space. Do.

According to the embodiment, since the lower shape of the outer cylinder is inverted conical, the angular velocity of the swirl flow increases as the swirl flow of the combustion exhaust gas descends the combustion space, and the centrifugal force is increased. For this reason, the dust can be separated more efficiently from the combustion exhaust gas.

In an embodiment, the lower burner opens in the upper inner circumferential wall of the outer cylinder at a position lower than the first combustion port so as to inject gas in the circumferential direction of the upper inner circumferential wall of the outer cylinder to form a swirl flow of combustion exhaust gas in the combustion space. It is preferable to have a 2nd combustion port to make.

There is a case where the demand for an air ratio or combustion temperature for reducing NOx, nitrous oxide, and unburned gas in the combustion exhaust gas does not coincide with the demand for a flow rate for separating the dust. For this reason, it is difficult to achieve both the improvement of the combustion efficiency and the improvement of the separation efficiency of a sold out by only a single stage burner. Thus, in the embodiment, secondary combustion air is injected from the second combustion port of the lower burner in the circumferential direction of the inner circumferential wall of the outer cylinder. Therefore, secondary combustion air is mixed in the unburned gas after the primary combustion, and combustion efficiency is improved and NOx, nitrous oxide, or unburned gas is reduced. In addition, the angular velocity of the swirl flow increases, thereby increasing the efficiency of separating the dust. The circumferential direction of the inner circumferential wall is the intangential tangential direction. In this case, the combustion exhaust gas refluxed from the downstream of the heat utilization apparatus can also be used as secondary combustion air.

In the embodiment, it is preferable to further have a cooling gas injection pipe having a gas injection port that opens in the inner circumferential wall of the outer cylinder at a position below the second combustion port of the lower burner.

In the thermal decomposition furnace disposed upstream of the combustion apparatus, organic waste is thermally decomposed using hot air. The use of hot steam instead of hot air can also pyrolyze organic waste. In some cases, the organic waste may be thermally decomposed by heating the organic waste indirectly in the presence of high temperature steam. Hazardous contaminants such as PCBs (polychlorinated biphenyls) and dioxins contained in organic wastes are difficult to decompose at low heating temperatures. PCBs and dioxins are gradually decomposed with an increase in temperature, but are not completely decomposed 100%, and trace amounts remain undecomposed. In the embodiment, the combustion exhaust gas is 900 ° C or higher, and also 950 ° C or higher or 1000 ° C or higher in order to further burn the high temperature pyrolysis gas in the combustion apparatus. For this reason, a part of a combustion apparatus becomes high locally, and it is easy to produce a problem, such as making a nonuniformity of temperature distribution. For this reason, it is difficult to control the operation of the combustion device. In order to prevent the occurrence of such nonuniformity of temperature distribution, a method of injecting a cooling gas into the combustion space, diluting the high temperature combustion exhaust gas and lowering the temperature is considered.

According to the embodiment, as the cooling gas from the cooling gas injection pipe, the combustion exhaust gas whose temperature refluxed from the downstream of the heat utilization apparatus is lowered is injected in the circumferential direction of the inner circumferential wall of the outer cylinder in the region after the combustion of the unburned gas. As a result, the high temperature secondary combustion exhaust gas is diluted with the low temperature combustion exhaust gas. Thus, overheating in the lower region of the combustion space is prevented. In addition, the flow rate of the combustion exhaust gas is further increased, whereby the separation efficiency of the dust is improved.

In an embodiment, it is preferable to further have a dust collection container communicating with the lower portion of the outer cylinder.

According to the embodiment, when the attached sold out, ie, the sold out lump grows and its thickness increases, the sold out lump is peeled off from the inner circumferential wall of the outer cylinder by its own weight, and the removed sold out lump falls naturally in the sold out container. For this reason, mechanical removal means, such as a scraping apparatus, are unnecessary.

In an embodiment, it is preferable that the inner cylinder is disposed coaxially with the outer cylinder in the outer cylinder so that the radial distance from the outer cylinder to the inner cylinder is substantially evenly over the entire circumference.

According to the embodiment, when the inner cylinder is disposed coaxially with the outer cylinder in the outer cylinder, the radial distance, i.e., the width, of the combustion space becomes equal. As a result, the combustion exhaust gas stream does not generate turbulent flow and descends while turning smoothly, so that the separation recovery efficiency of the dust is improved.

Hereinafter, various embodiments will be described with reference to the accompanying drawings.

(First embodiment)

The combustion apparatus of the first embodiment will be described with reference to FIGS. 1 and 2.

The waste disposal system 1 of the Example shown in FIG. 1 is equipped with the thermal decomposition furnace 3, the combustion apparatus 4, the heat utilization apparatus 5, and the dust collection container 6. As shown in FIG. In the system of this processing system 1, the exhaust gas is sucked out by a single blower or a plurality of blowers (not shown) arranged downstream. In addition, the whole of the processing system 1 is collectively managed and controlled by the process computer which is not shown in figure. The pyrolysis furnace 3 thermally decomposes organic waste under a high temperature reducing atmosphere. The combustion device 4 burns combustible pyrolysis gas generated in the pyrolysis furnace 3. The heat utilization apparatus 5 uses the high temperature combustion exhaust gas discharged | emitted from the combustion apparatus 4. Below, each component of the waste processing system 1 is demonstrated.

The pyrolysis furnace 3 is a horizontal kiln type | mold or a screw feeder type horizontal apparatus which has the hollow shaft chamber 31 which is rotationally driven, and the heating jacket 32 which heats this. The hollow shaft chamber 31 has a hollow cylindrical fireproof material wall and a supply screw, and is rotatably supported by a rotation drive mechanism (not shown). The organic waste is supplied to the hollow portion of the hollow shaft chamber 31 through the waste supply line L1 from a source not shown, and the feeding screw rotates in the forward direction to feed the organic waste in the axial direction. The waste supply line L1 includes, for example, a belt conveyor, a meter, a shooter and a hopper. The organic waste in the hollow shaft chamber 31 is heated by the fruit which passes through the heating jacket 32, and decompose | disassembles into a thermal decomposition gas and a thermal decomposition residue. The downstream end, ie, the outlet end, of the hollow shaft chamber 31 is connected to the upper burner 43 of the combustion device 4 via the pyrolysis gas line L2, and the pyrolysis gas is connected to the pyrolysis gas line L2. Discharged. Further, a carbide discharge line L5 is provided at a position downstream of the hollow shaft chamber 31, and carbide, which is a residue after thermal decomposition, is discharged from the hollow shaft chamber 31 through the carbide discharge line L5.

The heating jacket 32 is a jacket container surrounding at least a part of the hollow shaft chamber 31. The fruit supply pipe 33 and the fruit discharge pipe 34 are connected to the heating jacket 32. High temperature air, for example, 400 to 600 degrees of dry air, is supplied into the heating jacket 32 as a fruit through the fruit supply pipe 33 from the fruit supply source which is not shown in figure. After heating the organic waste in the hollow shaft chamber 31, the fruit is discharged from the heating jacket 32 through the fruit discharge pipe 34. In addition, the fruit supply pipe 33 and the fruit discharge pipe 34 may be connected by a return line to form a circulation circuit to reuse the used fruit. Moreover, as a heat source of the thermal decomposition furnace 3, well-known general purpose heating apparatuses, such as an electrical resistance heating apparatus or a combustion heating apparatus, can be used. From the economic point of view, a combustion heating device is most suitable. In addition, a well-known general purpose measuring instrument, such as a thermocouple, is used for the temperature measuring device which is not shown in figure.

The combustion apparatus 4 has a vertical furnace main body provided with the burners 43 and 44 of the upper and lower stages of a flame-jet system. The furnace body of the combustion apparatus 4 forms the double cylinder which consists of the outer cylinder 41 and the inner cylinder 42 arrange | positioned coaxially. The combustion space 40 is formed between the outer cylinder 41 and the inner cylinder 42. The upper part of the furnace body is blocked by the lid 45. The inner cylinder 42 has an opening 42a at a lower end thereof, and an upper end portion thereof communicates with the combustion exhaust gas line L3 through the lid 45. The inner cylinder 42 forms a flow path through which the combustion exhaust gas is discharged from the combustion space 40. The combustion exhaust gas descends while turning the combustion space 40, passes through the internal flow path of the inner cylinder 42 from the lower end opening 42a of the inner cylinder, and passes through the combustion exhaust gas line L3 connected to the upper end to utilize heat. Is sent to the device 5.

The upper and lower two-stage burners 43 and 44 respectively penetrate the first and second combustion holes 43a and 44a through the outer cylinder 41 at the upper half of the outer cylinder 41 and open to the inner circumferential wall of the outer cylinder 41. Have The upper burner 43 is connected to the hollow shaft chamber 31 of the pyrolysis furnace 3 via the pyrolysis gas line L2, and flammable pyrolysis gas is supplied from the pyrolysis furnace 3. Moreover, the upper burner 43 is connected with the primary combustion air supply line L6, and primary combustion air is supplied. When primary combustion air is simultaneously injected from the upper burner 43 together with the pyrolysis gas, both are mixed and combusted.

On the other hand, the lower burner 44 is connected with the secondary combustion air supply line L7, and secondary combustion air is supplied. When the secondary combustion air is injected from the lower burner 44, the unburned gas of the pyrolysis gas primaryly burned by the upper burner 43 is mixed with the secondary combustion air and combusted. Therefore, NOx, nitrous oxide, or unburned gas is reduced.

The heat utilization device 5 has an inlet connected to the combustion exhaust gas line L3 and an outlet connected to the low temperature combustion exhaust gas line L4. The main body of the heat utilization apparatus 5 has a flow path through which a heat exchange medium that can exchange heat with combustion exhaust gas flows. As the heat utilization apparatus 5, a waste heat boiler can be used, for example.

The dust collection container 6 is attached to the lower portion of the combustion device 4. The dust collection container 6 has an opening 40a in communication with the combustion space 40 for recovering the dust generated by the combustion reaction of the combustion device 4. The dust separated from the combustion exhaust gas in the combustion device 4 is settled in the recovery container 6 through the opening 40a or peeled off from the wall by its own weight after being attached to the inner circumferential wall of the outer cylinder 41. And drop into recovery container 6. In addition, an adjustment valve (not shown) is mounted in the opening 40a between the combustion device 4 and the dust collection container 6 to recover the dust by opening and closing the adjustment valve periodically or temporarily opening or closing according to the driving situation. You may also

With reference to FIG. 2, the structure and effect | action of the two stage burner of a combustion apparatus are demonstrated in detail.

The upper and lower two stage burners 43 and 44 separate the outer cylinder 41 by a predetermined distance in the axial direction, that is, the vertical direction, of the apparatus in order to completely burn the unburned portion of the pyrolysis gas that has not been burned in the first combustion. ) Is mounted. The mounting position of the burners 43 and 44 in the circumferential direction of the outer cylinder 41, that is, the orientation, is relatively free. As shown to FIG.2 (A)-FIG.2 (D), the position of the burners 43 and 44 can be arrange | positioned variously. For example, as shown to FIG. 2 (A), the upper burner 43 and the lower burner 44 may be attached to the same orientation so that it may overlap up and down. The combustion injection from the 1st combustion port 43a and the combustion injection from the 2nd combustion port 44a have the same orientation. In addition, as shown in FIG.2 (B), the lower burner 44 may be attached to the bearing which shifted 90 degrees clockwise from the mounting orientation of the upper burner 43. As shown in FIG. The combustion injection from the 2nd combustion port 44a is delayed by 90 degrees from the combustion injection from the 1st combustion port 43a. In addition, as shown in FIG.2 (C), the lower burner 44 may be attached to the orientation which shifted 180 degree clockwise from the mounting direction of the upper burner 43. FIG. The combustion injection from the 2nd combustion port 44a is delayed 180 degrees from the combustion injection from the 1st combustion port 43a. In addition, as shown in FIG.2 (D), the lower burner 44 may be attached to the orientation which shifted 270 degrees clockwise from the mounting orientation of the upper burner 43. As shown in FIG. The combustion injection from the 2nd combustion port 44a is delayed by 270 degrees from the combustion injection from the 1st combustion port 43a.

Even when the upper and lower burners 43 and 44 are mounted in any of the orientations of Figs. 2A to 2D, the pyrolysis gas and the primary combustion air flow from the first combustion port 43a to the outer cylinder. It is injected in the tangential direction clockwise inscribed to the inner circumferential wall of 41, and from the second combustion port 44a, secondary combustion air is injected in the tangential direction of the clockwise direction inscribed to the inner circumferential wall of the outer cylinder 41. do. For this reason, combustion exhaust gas rotates in the clockwise direction in the figure within the combustion space 40.

In this embodiment, the combustion exhaust gas descends while turning the combustion space 40, passes through the internal flow path of the inner cylinder 42 from the lower end opening 42a of the inner cylinder, and also passes through the combustion exhaust gas line L3 to utilize heat. Is sent to the device 5. When centrifugal force acts on combustion exhaust gas, the dust which has a specific gravity larger than combustion gas flows in the periphery of a combustion space, adheres to the inner peripheral wall of the outer cylinder 41, and is isolate | separated from combustion exhaust gas. By this centrifugal action, the dust is efficiently separated from the combustion exhaust gas. Therefore, according to the combustion apparatus of the embodiment, the amount of sold-out contained in combustion exhaust gas can be reduced. In addition, the dust adhering to the downstream heat utilization apparatus is reduced by this, and the heat utilization efficiency of a heat utilization apparatus improves. In addition, secondary combustion air is injected from the lower burner 44, and unburned gas of the pyrolysis gas primaryly burned by the upper burner 43 is mixed with the secondary combustion air and combusted, so that NOx or nitrous oxide, Or unburned gas is reduced. In addition, according to the combustion apparatus of the embodiment, when the adhesion amount of the dust increases, the attached and deposited dust is peeled off from the inner circumferential wall by its own weight, and the peeled off dust is recovered from the lower part of the combustion apparatus. Sold out again on the inner circumferential wall after the sold out. When the adhesion amount of the sold out increases, the sold out naturally peels off at its own weight. In this way, the combustion device 4 of the first embodiment can efficiently recover the dust separated from the combustion exhaust gas.

(Second Embodiment)

Next, a second embodiment will be described with reference to FIG. In addition, description of the part which is common in 1st Example is abbreviate | omitted.

4A of the combustion apparatus of this embodiment is not equipped with the dust collection container 6 shown in FIG. 1 in the lower part of the apparatus. The combustion device 4A includes a bottom lid 49 that closes the lower end opening of the outer cylinder 41. The bottom lid 49 is openable.

In the combustion apparatus of this embodiment, the sold-out 60 is attached to the inner circumferential wall of the outer cylinder 41 and finally peeled off from the wall and deposited on the bottom lid 49. The bottom lid 49 is opened regularly, and the accumulated sold out 60 is recovered from the outer cylinder 41.

According to this embodiment, the bottom lid 49 attaching type | mold outer cylinder 41 functions as a sold-out collection container. Therefore, since the combustion apparatus 4A does not need a separate collection container, the combustion apparatus 4A becomes small. In addition, similarly to the combustion apparatus 4 of the first embodiment, the combustion device 4A of the present embodiment can efficiently separate the dust from the combustion exhaust gas, so that the dust can be efficiently recovered. Therefore, NOx, nitrous oxide, or unburned gas contained in the combustion exhaust gas discharged from the combustion device 4A is reduced, and the amount of sold out is reduced. In addition, the dust adhering to the downstream heat utilization apparatus is reduced by this, and the heat utilization efficiency of a heat utilization apparatus improves.

(Third Embodiment)

Next, a third embodiment will be described with reference to FIG. In addition, description of the part which is common in each said embodiment is abbreviate | omitted.

In the combustion apparatus 4B of this embodiment, the shape of the lower half part of an outer cylinder is a reverse cone shape. That is, the shape of the upper half part 41a of an outer cylinder is cylindrical shape. The shape of the lower half part 41b of an outer cylinder is a reverse cone shape, and the lower part 41c of an outer cylinder is a small cylindrical shape. The bottom part 41c becomes a discharge part. As the lower half portion 41b of the outer cylinder having an inverted cone shape moves downward, the inner diameter gradually decreases. The lower end opening 42a of the inner cylinder is located in the lower half portion 41b of the outer cylinder having an inverted cone shape. Further, the lowermost portion 41c of the outer cylinder, that is, the discharge portion, has an opening 41d at the lower end. The opening 41d of the discharge portion communicates with the dust collection container (not shown).

In the combustion device 4B of the present embodiment, the dust 60 is attached to the inner circumferential wall of the lower half portion 41b of the outer cylinder having an inverted cone shape, peeled off from the wall surface, and the opening 41d of the lowermost portion 41c serving as the discharge portion. It passes through and falls into a recovery container (not shown).

According to this embodiment, since the shape of the lower half of the outer cylinder is a reverse cone shape, the angular velocity of the swirl flow of the combustion exhaust gas increases as the swirl flow of the combustion exhaust gas lowers the combustion space, thereby increasing the centrifugal force. For this reason, the combustion apparatus 4B of an Example can isolate | separate the dust more efficiently from combustion exhaust gas, and can collect | recover the dust efficiently. Therefore, while NOx, nitrous oxide, or unburned gas contained in the combustion exhaust gas discharged from the combustion device 4B is reduced, the amount of sold out is further reduced. Thereby, the dust adhered to the downstream heat utilization apparatus is reduced, and the heat utilization efficiency of a heat utilization apparatus improves.

(Fourth Embodiment)

Next, a fourth embodiment will be described with reference to Figs. In addition, description of the part which is common in said each Example is abbreviate | omitted. 5 shows a waste treatment system 1C of the present embodiment.

4C of the combustion apparatus of this embodiment has the cooling gas injection pipe 46 attached to the inverted-cylindrical cylindrical part of an outer cylinder. The exhaust gas circulation line L4 from the outlet side of the heat utilization device 5 is connected to the cooling gas injection pipe 46. The used low-temperature combustion exhaust gas from the heat utilization device 5 is injected into the lower portion of the combustion space 40 from the cooling gas injection pipe 46.

There may be a case where the demand for an air ratio or combustion temperature for reducing NOx, nitrous oxide, and unburned content in combustion exhaust gas does not coincide with the demand for a flow rate for separating dust. In this case, by incorporating another fluid into the combustion exhaust gas after the secondary combustion to increase the flow rate, the efficiency of separating the dust is increased. When the low temperature combustion exhaust gas which has passed through the heat utilizing apparatus is used as the fluid to be mixed, the thermal efficiency is improved as compared with the case of using air.

The low temperature combustion exhaust gas after heat use is in the range of 100 degreeC or more and 350 degrees C or less. The low temperature combustion exhaust gas is introduced into the combustion space 40 from the cooling gas introduction pipe 46 via the exhaust gas circulation line L4 which is the low temperature combustion exhaust gas line.

The combustion apparatus of this embodiment injects the low temperature combustion exhaust gas after heat use from the cooling gas injection pipe 46 into the circumferential direction of the inner circumferential wall of the outer cylinder in the region after the unburned gas combustion. According to the combustion apparatus of the present embodiment, overheating in the lower region of the combustion space is prevented by diluting the high temperature secondary combustion exhaust gas with the low temperature cooling gas. In addition, the flow rate of the combustion exhaust gas is further increased, the separation efficiency of the dust is improved, and the dust can be efficiently recovered. Therefore, NOx, nitrous oxide, or unburned gas contained in the combustion exhaust gas discharged from the combustion device 4C is reduced, and the amount of sold out decreases. Thereby, the dust adhered to the downstream heat utilization apparatus is reduced, and the heat utilization efficiency of a heat utilization apparatus improves.

According to the combustion apparatus of some embodiments described above, the amount of sold out can be reduced while the NOx, nitrous oxide, or unburned gas contained in the combustion exhaust gas discharged from the combustion apparatus is reduced.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. These examples and modifications thereof are included in the scope and gist of the invention, and are included in the invention and equivalent scope of the claims.

1: waste treatment system 3: pyrolysis furnace
4: combustion apparatus 5: heat-using apparatus
6: Sold out recovery container 31: Hollow shaft seal
32: heating jacket 33: fruit supply pipe
34: fruit discharge pipe 40: combustion space
40a: opening 41: outer cylinder
42: inner cylinder 42a: opening
43: upper burner 43a: first combustion port
44: lower burner 44a: second combustion port

Claims (10)

A combustion apparatus for combusting flammable pyrolysis gas generated in a pyrolysis furnace of a waste treatment system for pyrolyzing organic waste,
An outer cylinder defining an combustion space for combusting the pyrolysis gas and an inner cylinder, the inner cylinder having a vertical double forming a flow path for discharging combustion exhaust gas from the combustion space; Tubular furnace body,
An upper burner injecting the pyrolysis gas and the primary combustion air into the combustion space to mix and burn the pyrolysis gas and the primary combustion air;
A pyrolysis gas supply line for supplying the pyrolysis gas to the upper burner;
A primary combustion air supply line for supplying the primary combustion air to the upper burner;
A lower burner disposed below the upper burner and injecting secondary combustion air into the combustion space to mix and combust unburned gas and the secondary combustion air in the combustion space;
A secondary combustion air supply line for supplying the secondary combustion air to the lower burner
And,
And the upper burner has a first combustion port opening in the upper inner circumferential wall of the outer cylinder for injecting the pyrolysis gas and the primary combustion air in the circumferential direction of the upper inner circumferential wall of the outer cylinder. The method of claim 1,
The shape of the lower part of the said outer cylinder is an inverted cone shape whose diameter gradually decreases, The combustion apparatus characterized by the above-mentioned. The method according to claim 1 or 2,
The lower burner has a second combustion port opening in the upper inner circumferential wall of the outer cylinder at a position below the first combustion port, which injects the secondary combustion air in the circumferential direction of the upper inner circumferential wall of the outer cylinder. Combustion apparatus. The method of claim 3,
And a cooling gas injection tube having a gas injection hole that is opened in the inner circumferential wall of the outer cylinder at a position below the second combustion port of the lower burner. The method of claim 1,
The upper burner and the lower burner are installed in the upper half of the outer cylinder. The method of claim 2,
Combustion apparatus characterized by the shape of the lower half part of the said outer cylinder provided in reverse cone shape. The method of claim 1,
A combustion device further comprising a dust collection container communicating with the combustion space below the outer cylinder. The method of claim 1,
And the inner cylinder is disposed coaxially with the outer cylinder. The method of claim 1,
A combustion device further comprising a lid that can be opened and closed at a lower portion of the outer cylinder. The method of claim 1,
And the inner cylinder introduces the combustion exhaust gas from the lower end and discharges the combustion exhaust gas from the upper end.

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