JP3722609B2 - Waste pyrolysis melting combustion equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a waste pyrolysis melting combustion apparatus used for melting combustion treatment of waste such as municipal waste.
[0002]
[Prior art]
FIG. 4 shows a schematic system diagram of a conventional waste pyrolysis melting and combustion apparatus. In FIG. 4, 50 is a waste supply apparatus, 51 is a pyrolysis drum, 52 is a heated gas heater, 53. Is a separator, 54 is a pyrolysis gas conduit, 55 is a combustion melting furnace, 56 is a slag cooling tank, 57 is a double damper, 58 is a cooling vibration conveyor, 59 is a cooling water pipe, 60 is a cooling water circulation pump, and 61 is a heat An exchanger, 62 is a nitrogen gas supply pipe, 63 is a bucket conveyor, 64 is a pyrolysis residue sorting device, 65 is a pulverizer, 66 is a silo, and 67 is a blower.
[0003]
Thus, the waste A supplied to the pyrolysis drum 51 by the supply device 50 is heated to a temperature of 300 ° C. to 600 ° C. under the interruption of air by the heating gas B from the heating gas heater 52. And decomposed into pyrolysis gas C and pyrolysis residue D. The pyrolysis gas C is mainly composed of moisture, CO, CO ₂ , H ₂ and hydrocarbons, and the pyrolysis residue D is a mixture of carbon residue, iron, aluminum, glass and the like.
[0004]
The pyrolysis gas C and pyrolysis residue D generated in the pyrolysis drum 51 are introduced into a separator 53 adjacent to the pyrolysis drum 51, where it is separated into pyrolysis gas C and pyrolysis residue D by gravity. Is done.
[0005]
The pyrolysis gas C is directly introduced into the combustion melting furnace 55 via the pyrolysis gas conduit 54, and the pyrolysis residue D is a recovery of valuable materials such as iron and aluminum and a carbon residue after the recovery of the valuable materials. For pulverization and fuel conversion, it is introduced into a pyrolysis residue sorting device 64 (consisting of a sieve, a magnetic separator, an aluminum sorter, etc.) through a double damper 57, a cooling vibration conveyor 58 and a bucket conveyor 63.
[0006]
That is, the pyrolysis residue D falls from the separator 53 to the double damper 57 and is sent to the cooling vibration conveyor 58 while the double damper 57 blocks the atmosphere in the separator 53 and the cooling vibration conveyor 58. It should be noted that the inside of the separator 53 and the inside of the cooling vibration conveyor 58 are cut off when the low-temperature atmospheric gas (nitrogen gas or the like) in the cooling vibration conveyor 58 is sucked into the separator 53 and the pyrolysis gas conduit 54. This is because the tar contained in the cracked gas C is solidified and the pyrolyzed gas conduit 54 may be blocked.
[0007]
The pyrolysis residue D sent to the cooling vibration conveyor 58 is indirectly cooled with cooling water in a low-oxygen or oxygen-free state in the cooling vibration conveyor 58 to a temperature of about 450 ° C. to about 80 ° C. After being lowered to a lower level, the sheet is conveyed upward by the bucket conveyor 63 and sent to the pyrolysis residue sorting device 64. The reason why the pyrolysis residue D is cooled in a low-oxygen or oxygen-free state is to prevent the pyrolysis residue D from being burned or exploded. Further, nitrogen gas is supplied into the cooling vibration conveyor 58 from the nitrogen gas supply pipe 62 in order to make the inside of the cooling vibration conveyor 58 in a low oxygen or oxygen-free state.
[0008]
And, as for the thermal decomposition residue D sent to the thermal decomposition residue sorting device 64, valuables such as iron and aluminum are recovered here. The remaining carbon residue D ′ is subsequently pulverized into fine particles having a particle diameter of 1 mm or less by the pulverizer 65 and converted into fuel.
[0009]
The pulverized carbon residue D ′ is stored in the silo 66 and then sent to the combustion melting furnace 55 by pneumatic transportation, where it is burned and melted together with the pyrolysis gas C to become molten slag F. The molten slag F is dropped and discharged into the slag cooling layer 56 to become a granulated slag.
Further, the high-temperature (1200 ° C. to 1400 ° C.) combustion exhaust gas G generated in the combustion melting furnace 55 flows into a waste heat boiler (not shown) and is heat-recovered here, and then an exhaust gas treatment device (not shown). After that, it becomes clean gas and is discharged into the atmosphere.
[0010]
[Problems to be solved by the invention]
By the way, in the conventional pyrolysis melting and combustion apparatus for waste, since the pyrolysis residue D discharged from the pyrolysis drum 51 is sequentially moved downward by gravity, the pyrolysis drum 51 is placed on the floor surface. The double damper 57, the cooling vibration conveyor 58, the bucket conveyor 63, and the like (portion surrounded by the one-dot chain line in FIG. 4) must be installed in the basement.
In particular, in a large-scale pyrolysis melt combustion apparatus, the apparatus installed at the bottom may be close to 10 m underground.
As described above, the conventional pyrolysis melt combustion apparatus has a problem that a large basement is required for installation, the installation space is increased, and the installation cost is significantly increased.
[0011]
The present invention has been made in view of such problems, and its purpose is to provide a waste pyrolysis melting combustion apparatus that eliminates the need for a basement and can greatly reduce installation space and installation cost. To provide.
[0012]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention is a rotary pyrolysis drum which is obtained by pyrolyzing waste materials into pyrolysis gas and pyrolysis residue, and a shaft of the pyrolysis drum. Disposed on the line and connected to the pyrolysis drum in communication with the pyrolysis gas and pyrolysis residue, and disposed on the axis of the pyrolysis drum, the tip of the discharge pipe is inserted and discharged A rotary cooling drum that indirectly cools the pyrolysis residue sent from the pipe for use in connection with the cooling drum through a gas passage formed outside the tip of the discharge pipe, and separated in the cooling drum. A separator that separates the fine pyrolysis residue in the pyrolysis gas by guiding the pyrolysis gas through the gas passage, and the pyrolysis residue in the cooling drum and the fine pyrolysis residue in the separator to the pyrolysis residue sorting device A transport device to transport and It is characterized in that provided.
[0013]
The invention according to claim 2 of the present invention is characterized in that screw blades are provided on the outer peripheral surface of the discharge pipe to convey fine pyrolysis residues dropped into the gas passage into the separator.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a schematic system diagram of a waste pyrolysis melting and combustion apparatus according to an embodiment of the present invention. In FIG. 1, 1 is a supply screw feeder for waste A, and 2 is a pyrolysis drum. 3 is a heated gas inlet side casing, 4 is a heated gas outlet side casing, 5 is a heated gas heater, 6 is a heated gas circulation fan, 7 is a discharge pipe, 8 is a cooling drum, 9 is a separator, and 10 is a bucket. Conveying device comprising conveyor 10 ′ and pyrolysis residue conveyor 10 ″, 11 is a pyrolysis residue sorting device, 12 is a pulverizer, 13 is a silo, 14 is a combustion melting furnace, 15 is a slag cooling tank, 16 is a waste heat boiler, Reference numeral 17 is a dust collector, 18 is an exhaust gas treatment device, 19 is an induction fan, and 20 is a chimney.
[0015]
As shown in FIG. 2, the pyrolysis drum 2 has a drum main body 21 in which a heated gas inlet 21a and a heated gas outlet (not shown) are formed at both ends, and is disposed in an airtight manner at both end positions in the drum main body 21. A pair of tube plates 22 and both end portions thereof are inserted and supported in an airtight manner in both tube plates 22, and are disposed in the drum body 21 and a plurality of heating tubes 23 along the axial direction of the drum body 21. It consists of a scraping plate 24 of pyrolysis residue D, and the heating gas B is passed through the heating gas inlet 21a, the heating pipe 23 and the heating gas outlet, and is surrounded by the body portion of the drum main body 21 and the two pipe plates 22. The waste A is subjected to dry distillation pyrolysis in the space (hereinafter referred to as dry distillation pyrolysis space).
[0016]
A waste supply port (not shown) on the heated gas outlet side of the pyrolysis drum 2 supplies waste A sent by the supply screw feeder 1 to the space for dry distillation pyrolysis ( However, the pyrolysis gas C and pyrolysis residue D generated in the space for pyrolysis pyrolysis are discharged to the tube plate 22 on the heating gas inlet 21a side of the pyrolysis drum 2 (right side in FIG. 2). Each discharge port 25 is formed.
[0017]
Further, the heated gas inlet side casing 3 and the heated gas outlet side casing 4 are connected to the heated gas inlet 21 a and the heated gas outlet of the pyrolysis drum 2 in a communicating state. The heating gas inlet side casing 3 and the heating gas outlet side casing 4 are sealed to the heating gas inlet 21a and the heating gas outlet of the pyrolysis drum 2, and the pyrolysis drum 2 rotates with respect to both the casings 3 and 4. Each is connected so that it can.
Accordingly, the heated gas B supplied from the heated gas heater 5 to the heated gas inlet side casing 3 is discharged from the heated gas outlet side casing 4 through the heated gas inlet 21a, the heated pipe 23, and the heated gas outlet.
[0018]
The pyrolysis drum 2 is inclined to a support roller 26 on a support stand (not shown) installed on the floor surface, with a waste supply port positioned above the discharge port 25 side (about horizontal). (Inclination angle of 1.5 degrees) is rotatably supported, and is rotationally driven at a rotational speed of about 1 to 3 rpm by a rotational drive device (not shown) comprising a motor and a gear type transmission mechanism. It has become.
A rotating ring 27 is provided on the outer peripheral surface of the drum body 21 of the pyrolysis drum 2, and this portion is supported by the support roller 26.
[0019]
The gas heater 5 includes an oil burner or a gas burner that uses fossil fuel such as oil or natural gas as fuel, and is connected to the heating gas inlet side casing 3 and the heating gas outlet side casing 4 respectively. The high-temperature heating gas B can be supplied to the heating tube 23 as a heating medium for heating the waste A.
[0020]
That is, the heated gas B heated to 500 ° C. to 600 ° C. by the heated gas heater 5 is heated gas conduit 28, heated gas inlet side casing 3, heated pipe 23, heated gas outlet side casing 4, heated gas conduit 28, and It circulates and circulates in the loop line composed of the heated gas circulation fan 6 and the like, supplies heat energy to the waste A while passing through the heating pipe 23, and heats itself at a temperature of 250 ° C to 300 ° C. It flows out from the gas outlet side casing 4.
The high-temperature heating gas B from the heating gas heater 5 is a clean gas body that does not contain corrosive substances such as HCl because it uses fossil fuels such as petroleum and natural gas as fuel.
[0021]
As shown in FIG. 2, the discharge pipe 7 is arranged on the axis of the pyrolysis drum 2 and is connected to the discharge port 25 of the pyrolysis drum 2, and the heating gas inlet 21a of the pyrolysis drum 2 is heated. The gas inlet side casing 3 and the separator 9 are inserted into the gas inlet side casing 3 and the separator 9 to rotate together with the pyrolysis drum 2.
[0022]
Further, the distal end portion (the right end portion in FIG. 2) of the discharge pipe 7 is inserted into the cooling drum 8 and can guide the pyrolysis gas C and pyrolysis residue D in the pyrolysis drum 2 into the cooling drum 8. It is like that.
[0023]
The cooling drum 8 is rotatably arranged on the axis of the pyrolysis drum 2, indirectly cools the pyrolysis residue D sent from the discharge pipe 7 and discharges it to the bucket conveyor 10 ′. The pyrolysis gas C in the cooling drum 8 can be led to the separator 9.
[0024]
That is, as shown in FIGS. 2 and 3, the cooling drum 8 includes a cylindrical body 29 in which a plurality of cooling pipes 29a are arranged in a circular shape and adjacent cooling pipes 29a are connected in an airtight manner, and An annular and pipe-shaped inlet-side header 30 and outlet-side header 31 connected to both ends of the cooling pipe 29a, and a cooling-water supply pipe 32 and cooling water connected to the inlet-side header 30 and the outlet-side header 31, respectively. The discharge pipe 33, a pair of end plates 34 arranged in an airtight manner at both ends in the body 29, and one end plate 34 (on the right side in FIGS. 2 and 3) are connected to communicate with the inside of the body 29, The pyrolysis residue pipe 35 for discharging the pyrolysis residue D in the fuselage 29 to the bucket conveyor 10 ′ and the other end plate 34 (left side in FIGS. 2 and 3) are connected so as to communicate with the interior of the fuselage 29 for discharge. Between the pipe 7 The thermal decomposition gas pipe 37 forming the gas passage 36 and the scraping plate 38 of the thermal decomposition residue D disposed in the body 29 are cooled. The thermal decomposition residue D in the body 29 is cooled by the cooling pipe 29a. Then, the pyrolysis residue pipe 35 is discharged into the bucket conveyor 10 ′, and the pyrolysis gas C is reversed in the body 29 so as to be introduced into the separator 9 from the gas passage 36.
[0025]
As shown in FIG. 3, the cooling water supply pipe 32 and the cooling water discharge pipe 33 are disposed so as to pass through the casing 10a of the bucket conveyor 10 'and rotate together with the body 29. The rotary joints 39 (disposed on the axis of the cooling drum 8) provided outside the casing 10a of 10 'are connected to each other.
Accordingly, the cooling water E is supplied to the cooling pipe 29a through the rotary joint 39, the cooling water supply pipe 32 and the inlet side header 30, and after cooling the thermal decomposition residue D in the cooling drum 8, the outlet side header 31 and the cooling water are cooled. The water is discharged through the water discharge pipe 33 and the rotary joint 39.
[0026]
The portion of the cooling water supply pipe 32 and the cooling water discharge pipe 33 that penetrates the casing 10 a of the bucket conveyor 10 ′ has a double pipe structure in which a part of the cooling water supply pipe 32 is inserted into the cooling water discharge pipe 33. It has become.
[0027]
Further, the pyrolysis residue pipe 35 and the cooling water discharge pipe 33 are provided with a sealing plate 40 that is slidably and rotatably in contact with the casing 10a of the bucket conveyor 10 ', and into the casing 10a of the pyrolysis residue pipe 35. The inserted portion and the portion of the cooling water discharge pipe 33 that passes through the casing 10a are sealed.
[0028]
The cooling drum 8 is arranged on the axis of the pyrolysis drum 2, and the inlet side (pyrolysis gas pipe 37 side) is on the outlet side of the support roller 41 on a support base (not shown) installed on the floor surface. Rotation comprising a motor and a gear-type transmission mechanism that is rotatably supported with an inclined posture (an inclination angle of about 1.5 degrees with respect to the horizontal) located above (the pyrolysis residue pipe 35 side). A drive device (not shown) is driven to rotate at an appropriate rotation speed.
A rotating ring 42 is provided on the outer peripheral surface of the body 29 of the cooling drum 8, and this portion is supported by the support roller 41.
[0029]
As shown in FIG. 2, the separator 9 is disposed so as to surround a part of the discharge pipe 7 (position portion between the heating gas inlet side casing 3 and the cooling drum 8). The cooling drum 8 is connected to be able to rotate while being sealed by the pyrolysis gas pipe 37.
Accordingly, the pyrolysis gas C in the cooling drum 8 is guided from the cooling drum 8 through the gas passage 36 into the separator 9, where the fine pyrolysis residue D in the pyrolysis gas C is separated by gravity. It has become so.
[0030]
Further, a pyrolysis gas conduit 43 for introducing the pyrolysis gas C to the combustion melting furnace 14 is provided at the upper end portion of the separator 9, and a fine pyrolysis residue D separated at the lower end portion of the separator 9 is supplied to the bucket conveyor 10 '. A rotary valve 44 for conveying and a pyrolysis residue conveyor 10 ″ are connected to each other.
[0031]
In the gas passage 36 communicating with the inside of the separator 9 and the inside of the cooling drum 8, screw blades 45 for conveying the fine pyrolysis residue D falling into the gas passage 36 into the separator 9 are disposed. Yes. The screw blades 45 are provided on the outer peripheral surface of the discharge pipe 7.
[0032]
In FIG. 2, 46 is a partition plate provided between the separator 9 and the heated gas inlet side casing 3. The partition plate 46 is fixed to the outer peripheral surface of the discharge pipe 7 and rotates together with the discharge pipe 7. The partition plate 46 is in sliding contact with the separator 9 and the heated gas inlet side casing 3. The space between the separator 9 and the heated gas inlet side casing 3 is sealed.
[0033]
Next, the operation of the waste pyrolysis melting combustion apparatus having the above configuration will be described.
Waste A such as municipal waste supplied into the pyrolysis drum 2 by the supply screw feeder 1 is heated from room temperature to 300 ° C. by the heated gas B flowing in the heating tube 23 in a state in which oxygen is substantially blocked. It is heated to a temperature of 600 ° C., preferably 400 ° C. to 500 ° C., and stays in the pyrolysis drum 2 for about 1 hour after stirring and mixing by rotation. During this time, the waste A in the pyrolysis drum 2 is pyrolyzed, whereby a pyrolysis gas C and a solid pyrolysis residue D are generated in the pyrolysis drum 2.
[0034]
The pyrolysis of the waste A in the pyrolysis drum 2 is usually completed in about 1 hour, and approximately 75 wt% pyrolysis gas C and 25 wt% pyrolysis residue D are generated. The generated pyrolysis gas C is mainly composed of moisture, CO, CO ₂ , H ₂ and hydrocarbons, and contains a small amount of dust and tar. Further, the generated pyrolysis residue D is homogenized by being stirred and mixed in the pyrolysis drum 2 to form particles having a uniform size, and a char composed mainly of carbon and ash, It is a mixture with non-combustible materials such as iron, aluminum and glass.
[0035]
The pyrolysis gas C in the pyrolysis drum 2 is sent into the cooling drum 8 through the discharge pipe 7, and the pyrolysis residue D in the pyrolysis drum 2 is rotated by the pyrolysis drum 2. Then, it is fed into the discharge pipe 7 by the scraping action of the scraping plate 24 and is sent into the cooling drum 8 through the discharge pipe 7.
[0036]
The pyrolysis gas C fed into the cooling drum 8 is reversed in the cooling drum 8 and flows into the separator 9 through the gas passage 36 outside the discharge pipe 7, where the pyrolysis gas C enters the pyrolysis gas C. After the fine pyrolysis residue D contained is separated by gravity, it is guided to the combustion melting furnace 14 through the pyrolysis gas conduit 43. The fine pyrolysis residue D separated by the separator 9 is sent to the bucket conveyor 10 'through the rotary valve 44 and the pyrolysis residue conveyor 10 ".
The fine pyrolysis residue D dropped when the pyrolysis gas C passes through the gas passage 36 is sent into the separator 9 by the screw blade 45 provided outside the discharge pipe 7 and separated by the separator 9. The fine pyrolysis residue D is fed to the bucket conveyor 10 'via the rotary valve 44 and the pyrolysis residue conveyor 10 ".
[0037]
On the other hand, the pyrolysis residue D in the cooling drum 8 is indirectly cooled by the cooling pipe 29a in the rotationally driven cooling drum 8 and cooled to a temperature of about 80 ° C., and then the scraping plate 38 on the outlet side. Then, it is scraped up into the pyrolysis residue pipe 35 and fed into the bucket conveyor 10 ′ through the pyrolysis residue pipe 35.
Since the cooling drum 8 rotates and agitates the thermal decomposition residue D, the cooling surface can be used effectively.
Further, nitrogen gas is enclosed in the bucket conveyor 10 'in order to prevent the pyrolysis residue D from being ignited.
[0038]
The pyrolysis residue D sent from the bucket conveyor 10 ′ to the pyrolysis residue sorting device 11 (comprising a sieve, a magnetic separator, an aluminum sorter, etc.) collects valuable materials such as iron and aluminum. Further, the remaining pyrolysis residue D is continuously pulverized into fine particles having a particle diameter of 1 mm or less by the pulverizer 12 and converted into fuel, and then stored in the silo 13.
[0039]
The pyrolysis residue D stored in the silo 13 is continuously sent together with dust from the waste heat boiler 16, the dust collector 17 and the like to the combustion melting furnace 14 by air transportation, where it is combusted and melted together with the pyrolysis gas C. It becomes molten slag F.
That is, the fine pyrolysis residue D having a high carbon content supplied into the melt combustion apparatus 4 is combusted at a high temperature of about 1300 ° C. in the combustion melting furnace 14 together with the pyrolysis gas C. Since the combustion temperature (about 1300 ° C.) is about 100 to 150 ° C. higher than the melting temperature of ash, the pyrolysis residue D becomes molten slag F and is discharged into the slag cooling tank 15, so-called granulated slag and Become.
[0040]
In the combustion melting furnace 14, the generated dioxins are almost completely burned and decomposed together with other organic substances at an extremely high combustion temperature.
In the combustion melting furnace 14, various known means for maintaining good combustion, such as a multi-stage supply method of combustion air, an exhaust gas recombustion method, and a cyclone combustion method, are used alone or in combination. Of course you can.
[0041]
On the other hand, the high-temperature (1200 ° C. to 1400 ° C.) combustion exhaust gas G generated in the combustion melting furnace 14 flows into the waste heat boiler 16 and is heat-recovered there. Then, the dust collector 17 and the exhaust gas treatment device 18 are passed through. After that, it becomes a clean gas and is discharged from the chimney 20 into the atmosphere.
[0042]
【The invention's effect】
As described above, the pyrolysis melting and combustion apparatus for waste according to the present invention is provided with a rotary cooling drum on the axis of the pyrolysis drum, and a pipe for discharging pyrolysis gas and pyrolysis residue discharged from the pyrolysis drum. In order to cool the pyrolysis residue here, it is not necessary to install a double damper, cooling vibration conveyor, bucket conveyor, etc. in the basement as in the case of conventional pyrolysis melting and combustion equipment. Is no longer necessary.
As a result, the pyrolysis melting combustion apparatus of the present invention can significantly reduce the installation space and the installation cost as compared with the conventional pyrolysis melting combustion apparatus.
In addition, the cooling drum is a rotary drum that rotates and agitates the pyrolysis residue supplied inside to cool it, so that the cooling surface can be used effectively, and the overall length is shorter than the cooling vibration conveyor of the prior art. Thus, the installation space can be reduced.
In addition, the outer peripheral surface of the discharge pipe is provided with screw blades for transporting fine pyrolysis residues that have fallen into the gas passage communicating with the inside of the cooling drum and the separator into the separator. It is possible to prevent the pyrolysis residue from being deposited.
[Brief description of the drawings]
FIG. 1 is a schematic system diagram of a waste pyrolysis melting combustion apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic longitudinal sectional view of a main part of the pyrolysis melting combustion apparatus.
FIG. 3 is a longitudinal sectional view of a cooling drum of a pyrolysis melting combustion apparatus.
FIG. 4 is a schematic system diagram of a conventional waste pyrolysis melting combustion apparatus.
[Explanation of symbols]
2 is a pyrolysis drum, 7 is a discharge pipe, 8 is a cooling drum, 9 is a separator, 10 is a transport device, 11 is a pyrolysis residue sorting device, 36 is a gas passage, 45 is a screw blade, A is waste, C is pyrolysis gas, D is pyrolysis residue.

Claims (2)

The waste (A) is pyrolyzed pyrolyzing to form a pyrolysis gas (C) and a pyrolysis residue (D), and a rotary pyrolysis drum (2) is disposed on the axis of the pyrolysis drum (2). A pipe (7) for discharge of pyrolysis gas (C) and pyrolysis residue (D) connected to the pyrolysis drum (2) in communication, and disposed on the axis of the pyrolysis drum (2) for discharge A rotary cooling drum (8) for indirectly cooling the pyrolysis residue (D) sent from the discharge pipe (7) while the tip of the pipe (7) is inserted, and a cooling drum (8) The pyrolysis gas (C) connected in communication via a gas passage (36) formed outside the tip of the discharge pipe (7) and separated in the cooling drum (8) is guided by the gas passage (36). A separator (9) for separating the fine pyrolysis residue (D) in the pyrolysis gas (C); And (8) a pyrolysis residue (D) in the separator and (9) a fine pyrolysis residue (D) in the separator (9). Waste pyrolysis melting combustion equipment. A screw blade (45) is provided on the outer peripheral surface of the discharge pipe (7) to convey the fine pyrolysis residue (D) dropped into the gas passage (36) into the separator (9). The waste pyrolysis melting combustion apparatus of Claim 1.

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