JP4550512B2 - Waste pyrolysis treatment system - Google Patents

Description

  The present invention relates to a waste pyrolysis processing system for processing a workpiece such as waste by pyrolysis.

  Conventionally, as a waste treatment system that converts unsorted and untreated waste containing various pollutants into usable materials, for example, described in JP 2000-202419 A (Patent Document 1) There is known a pyrolysis system for treating a waste such as the above by pyrolysis.

  In such a waste treatment system, an object to be treated such as waste is supplied into a thermal decomposition furnace by a waste supply device via a pretreatment device, and is thermally decomposed at a temperature of about 550 ° C. in the thermal decomposition furnace. It is processed. As a general pyrolysis furnace, for example, an externally heated rotary kiln that heats a rotary drum from the outside is used.

  The organic polymer gas generated by pyrolysis in the pyrolysis furnace is reformed at a temperature of about 1100 ° C. by a gas reformer to become a low molecular combustible gas, and then from about 900 ° C. to 200 ° C. by a gas cooler. It is rapidly cooled to about 0 ° C. and further purified by a gas purification device. In the gas cleaning process performed by the gas purification device, removal of carbon dust by a bag filter and gas water cleaning by water are performed. The combustible gas purified by the gas purification device is supplied to the gas usage destination through the induction blower, the water seal device, and the supply blower. These pyrolysis furnaces, gas reformers, gas coolers, and gas purification devices are controlled by the induction blower to a slightly negative pressure state, so that air easily enters from the outside. The main part is provided with a sealing structure so that the excessive amount does not enter.

However, in the conventional waste pyrolysis treatment system, the pyrolysis gas generated by pyrolyzing the waste at about 550 ° C. and the reforming oxidant (air) are reacted in the gas reformer. A large amount of dust (hereinafter referred to as soot) is generated. It is important to improve the operating rate of the processing facility by efficiently transporting the soot to the subsequent stage and not blocking the important points. Further, the reformed gas contains a certain amount of chemical substance, and may adhere to a partially thin part or a part that solidifies in temperature, resulting in clogging. Therefore, measures to prevent this are necessary. In addition, as waste treatment technology, inventions related to patent applications of Japanese Patent Application Nos. 2003-068182, 2003-203553, and 2003-391159 are known as the inventions of the present inventors.
JP 2000-202419 A

  The present invention has been made in view of the above-described conventional problems, and by smoothly performing the optimal arrangement and structure of the device, the wiping, the slag discharge, and the removal of deposits, the waste treatment can be performed stably and. An object of the present invention is to provide a waste pyrolysis treatment system that has been made possible over a long period of time.

The invention of claim 1 accepts a pyrolysis furnace for thermally decomposing an object to be treated such as waste and an organic polymer gas generated by the thermal decomposition of the object to be treated in the pyrolysis furnace, A gas reformer that reforms and discharges into a low-molecular combustible gas in a gas reforming process, a gas cooler that receives and cools the combustible gas discharged from the gas reformer, and discharges the combustible gas; In the waste pyrolysis system comprising a gas purification device that receives and purifies the combustible gas discharged from the gas cooler, removes impurities, and discharges the purified combustible gas, the gas reforming The vessel is composed of a pre-reaction tower and a post-reaction tower, and has a concave shape by connecting the lower parts of the pre-reaction tower and the post-reaction tower, and the upper part of the pre-reaction tower is connected to the pyrolysis furnace. The organic polymer gas is accepted and the front A pyrolysis burner was attached in the vicinity of the upper part of the tower, and the discharge part at the upper part of the post-reaction tower was connected to the gas cooler to be reformed by high-temperature gas reforming treatment in the gas reformer. A low-molecular combustible gas is discharged to the gas cooler, and the gas cooler is loaded with a heat transfer tube for gas cooling, and passes through the heat transfer tube from above to the combustible gas. By connecting the lower part of the front part and the rear part of the quencher device so as to communicate with each other, the upper part of the front part is the low molecule of the gas reformer. It connected to the discharge part of flammable gas, and the upper part of the said quencher apparatus was connected to the said gas purification apparatus.

According to a second aspect of the present invention, in the waste pyrolysis treatment system according to the first aspect, the bottom part of the gas cooler that communicates with the front part and the rear part comprises a transfer screw, a cooling screw, and a discharge mechanism. A carbon ash removal mechanism is provided.

  The invention of claim 3 is the waste thermal decomposition treatment system according to claim 1 or 2, wherein an intermediate portion of a bug filter in which the vicinity of the upper part of the quencher device is vertically installed is connected, It is characterized in that the gas from the quencher device flows from the outer surface of the vertical filter cloth provided above the intermediate portion to the inside, and the gas flows upward.

  According to a fourth aspect of the present invention, in the waste thermal decomposition treatment system according to any one of the first to third aspects, a smoke tube boiler is installed at a front stage of the gas cooler, and a suction cone is placed in an upper can plate of the smoke tube boiler. And a wiping nozzle for spraying steam on the suction cone is disposed in a state of being slightly inserted into the suction cone.

  According to a fifth aspect of the present invention, in the waste pyrolysis processing system according to the fourth aspect, a small amount of steam is always allowed to flow through the nozzle of the gas cooler. It is a feature.

  According to the present invention, it is possible to smoothly perform the optimal arrangement of the device, the wiping, the slag discharge, and the removal of the deposits, and the waste pyrolysis process that enables efficient treatment operation of the waste treatment over a long period of time. A system can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  (First Embodiment) FIG. 1 is a block diagram of a waste pyrolysis treatment system according to one embodiment of the present invention. In FIG. 1, an object to be processed such as waste is supplied into a thermal decomposition furnace 103 by a waste supply device 102 via a pretreatment device 101 that performs crushing and iron recovery. The waste is processed by pyrolysis at a temperature of about 550 ° C. in the pyrolysis furnace 103. As the pyrolysis furnace 103, for example, an externally heated rotary kiln for heating a rotary drum from the outside is generally used, and an organic polymer gas generated by pyrolysis in the pyrolysis furnace 103 is used as a gas reformer 104. Here, it is reformed at a temperature of about 1100 ° C. to become a low-molecular combustible gas. The combustible gas is transferred to the gas cooler 105 where it is rapidly cooled from about 900 ° C. to about 200 ° C. and then supplied to the gas purification device 106. In the gas purification device 106, the cooled gas is purified to obtain a combustible gas from which impurities are removed. The gas purification device 106 includes a bag filter and a gas cleaning device, removes carbon dust with the bag filter, and gas cleaning with water is performed by the gas cleaning device 106. The combustible gas purified by the gas purification device 106 is supplied to the gas use destination through the induction blower 107, the water seal device 108, and the supply blower 109.

  On the other hand, the residue generated in the pyrolysis furnace 103 is discharged to the outside of the pyrolysis furnace 103 through the residue discharge device 111, valuable metal is recovered by the residue cooling, pulverization, and separation device 112, and the carbon residue is transferred to the granulator 113. It is sent and recycled as a granulated product. The cleaning water used for gas cleaning in the gas purification device 106 is sent to the water treatment device 114, neutralized, absorbed and adsorbed, subjected to purification water, and returned to the gas purification device 106.

  Note that the pyrolysis furnace 103, the gas reformer 104, the gas cooler 105, and the gas purification device 106 are controlled by the induction blower 107 in a slightly negative pressure state, so that the main part does not enter excessive air from the outside. Is provided with a sealing structure. In the pyrolysis processing system shown in FIG. 1, a reformed gas that is a combustible gas of a secondary material generated in the pyrolysis processing system is reused as an energy source of the pyrolysis furnace 103. In addition, it is recirculated for temperature adjustment of main components. Further, surplus gas generated by the system is burned according to the exhaust gas standard in a combustion furnace or the like, and released into the atmosphere.

  FIG. 2 is a plan view of the equipment arrangement of the waste pyrolysis processing system according to the first embodiment of this invention. In FIG. 2, an object to be treated such as waste is supplied into the pyrolysis furnace 3 by the waste supply apparatus 2 through the pretreatment apparatus 1, and is processed by pyrolysis at a temperature of about 550 ° C. in the pyrolysis furnace 3. Is done. Here, the organic polymer gas generated by pyrolysis in the pyrolysis furnace 3 is sent to the gas reformer 6 through the pyrolysis furnace outlet hood 4 and the gas connection pipe 5 and modified at a temperature of about 1100 ° C. The gas is cooled to about 900 ° C. to about 200 ° C. by the gas cooler 7, the soot is removed by the bag filter 8, and the gas is washed with water by the gas washing device 9. Is called. The combustible gas purified by the gas purification device 9 is supplied to the gas use destination through the induction blower 10, a water seal (not shown), and a supply blower.

  3, FIG. 4, and FIG. 5 are longitudinal sectional views of the equipment layout of the waste pyrolysis processing system according to the embodiment of the present invention. The gas reformer 6 has a concave shape, and pyrolysis gas and air (oxidant) enter from the upper part of the pre-reaction tower 13, and gas exits from the upper part of the post-reaction tower 14. The reformed gas containing soot coming out from the upper part of the post-reaction tower 14 enters from the upper part of the gas cooler (smoke tube boiler) 7 installed in the vertical form, and flows downward in the heat transfer pipe 15 to be gas cooled, It is folded at the bottom 16 of the gas cooler, flows upward in the quencher device 17, and is led to the middle part of the vertical bag filter 8 by controlling the quencher outlet temperature. By adopting such a configuration, the gas accompanied with soot can be easily transported inside the heat transfer tube 15 of the gas cooler 7.

  A product gas nozzle 18 and a water spray nozzle 19 are incorporated in the quencher device 17 shown in FIG. 3 so that the gas temperature sent to the bag filter 8 can be quickly controlled.

  A filter cloth 20 is attached above the middle part in the bag filter 8 shown in FIG. 4, the gas that has passed through the filter cloth 20 is sent to the gas cleaning device 9, and the soot collected by the filter cloth 20 falls to the lower part. Discharged outside.

  A gas cleaning device 9 shown in FIG. 5 includes a cooler 21 and a gas cleaning tower 22 and has a concave shape including an inlet pipe 23. The cooler 21 includes a water spray nozzle 24, the gas cleaning tower 22 includes a filler 25, a water spray nozzle 26, and an inlet pipe 23 incorporates a scraper 27 of an internal scraping mechanism. The scraper 27 is rotated by a motor 27a attached to the upper portion, and is dropped into the cooler 21 along with the gas while scraping off internal deposits. For this reason, it is possible to prevent the piping from being blocked by the adhering matter.

  The gas exiting the gas cleaning device 9 is sucked into the attracting blower 10 and sealed with water so that the water sealing device 11 cannot back flow. The gas sealed with the water sealing device 11 is configured to be sent to a subsequent supply blower (109 in FIG. 1).

  As shown in detail in FIG. 3, a transfer screw 28 is installed at the bottom of the gas reformer 6. The transfer screw 28 transfers the gutter 29 collected at the bottom to the cooling screw 30. The cooling screw 30 cools the soot and sends the soot to a discharge mechanism 31 (for example, a double damper configuration as shown in FIGS. 6 and 7). The discharge mechanism 31 discharges soot outside while blocking air from the outside.

  A double damper configuration in the distribution mechanism 31 will be described with reference to FIGS. FIG. 6 is a cross-sectional view of a discharge mechanism 80 that discharges carbon and melt accumulated in the floor of the reformer 6, and FIG. 7 is a cross-sectional view illustrating the operation of the discharge mechanism 80. In the discharge mechanism 80, upper and lower open / close lids 84 and 85 are attached to a rotationally movable portion 83 installed on a side wall 81 through a column 82, and has a two-layer structure. 7 (1), when the collar 86 accumulates on the upper opening / closing lid 84, the upper opening / closing lid 84 is opened and the collar 86 is dropped on the lower opening / closing lid 85 as shown in FIG. 7 (2). Next, as shown in FIG. 7 (3), the upper opening / closing lid 84 is closed to block the intrusion of the atmosphere, and then the lower opening / closing lid 85 is opened as shown in FIG. When the bag 86 is thrown away, the lower opening / closing lid 85 is closed as shown in FIG. By adopting a two-layer structure in this way, since there is a combustible gas or the like in the waste pyrolysis processing system, it is possible to prevent the atmosphere (oxygen) from flowing in rapidly.

  As shown in FIG. 3, a transfer screw 32 is installed at the bottom 16 of the gas cooler 7. The transfer screw 32 transfers the gutter 33 collected at the bottom 16 to the cooling screw 34. The cooling screw 34 cools the gutter 33 and sends the gutter 33 to a discharge mechanism 35 having a double damper configuration similar to that shown in FIGS. The discharge mechanism 35 discharges the gutter 33 to the outside while blocking air from the outside. The transfer screw 32 is rotationally driven by a motor 32a installed outside the apparatus. With this structure, the gutter 33 accumulated at the bottom 16 of the gas cooler 7 can be easily discharged, and the operation can be continued without gas blockage.

  As shown in FIG. 4, the soot 36 collected by the bag filter 8 falls to the lower part and is cooled by the cooling screw 37, and the soot 36 is discharged into the discharge mechanism 38 having the same double damper configuration as shown in FIGS. 6 and 7. Send 36. The discharge mechanism 38 discharges the soot outside while blocking air from the outside.

  As shown in FIG. 3, a gas discharge nozzle 39 and a control valve 40 are attached to the upper gas inlet of the gas cooler (smoke tube boiler) 7 so that the gas can be periodically discharged using steam generated by the boiler itself. It is. This prevents the clogging of the inlet portion of the gas cooler 7 in advance.

  As shown in FIG. 4, a backwash nozzle 41 and its control valve 42 are provided at the upper outlet portion of the filter cloth 20 of the bag filter 8 to blow out nitrogen from the filter cloth 20 by blowing out nitrogen. Further, the bag filter 8 is provided with an inlet valve 43 and an outlet valve 44 for partitioning the main body, and is provided with a bag bypass line (not shown). The bag filter 8 main body can be isolated from the system by closing and closing the gas to the bag bypass line.

  As described above, according to the first embodiment, each component device is formed into a concave shape, gas and the like are taken in from the upper part of the front stage, flowed down to the bottom part, soot and the like are collected, and the gas is raised to the rear stage part. By making the structure advancing to the component equipment, it is possible to efficiently separate and process soot and the like from the gas.

  (Second Embodiment) The waste pyrolysis treatment system of the second embodiment of the present invention is characterized by the structure of the gas cooler 7. Therefore, the configuration of other devices is the same as that of the first embodiment. FIG. 8 shows the structure of the gas cooler 7 employed in the present embodiment. With reference to FIG. 8, the wiping structure of the upper can plate of the gas cooler 7 will be described in detail. About 900 ° C. reformed gas flows from the gas reformer 6.

  The gas cooler 7 includes a pressure vessel, a heat transfer tube 46, an upper can plate 47, a lower can plate 48, and a top plate 49, and a steam rectifier 51 is placed above the upper can plate 47 in the upper smoke chamber 50. . The steam rectifier 51 is provided with a suction cone 52 corresponding to the same arrangement as the heat transfer tubes 46. The suction cone 52 has a truncated conical shape squeezed downward. Further, for each suction cone 52, a wiping nozzle 53 passes through the top plate 49 and is attached with a seal 54 while ensuring airtightness from the outside. The wiping nozzle 53 is assembled by being slightly inserted into the suction cone 52. The suction cone 52 has a structure in which a refractory material is poured into a refractory metal or a refractory metal frame.

  A steam generated by itself is used for the wiping, and a valve 55 for always flowing a small amount of steam is attached to the wiping nozzle 53, and a control valve 56 for flowing a large amount of steam intermittently during the wiping. Since a small amount of steam is constantly flown by the valve 55, the wiping nozzle 53 is not clogged and the thermal shock is reduced as compared with a configuration in which a large amount of steam is flowed intermittently, so that damage to the nozzle is prevented. it can.

  In addition, by attaching the suction cone 52, the steam ejected from the wiping nozzle 53 can be reliably put into the heat transfer tube 46. In addition, since the wiping nozzle 53 is assembled with the suction cone 52 being slightly inserted, even if the length of the wiping nozzle 53 is increased due to thermal expansion, it is prevented from interfering with the heat transfer tube 46 or the upper can plate 47 in advance. Can do.

  FIG. 9 is an explanatory diagram of the transfer screw 32 installed at the bottom 16 of the gas cooler 7. In FIG. 9, the soot 33 accumulated at the bottom of the gas cooler 7 is sent by the transfer screw 32 toward the cooling screw 34. The transfer screw 32 is rotationally driven by a motor 32a. The drive shaft passes through the partition wall 57 and is connected to the screw 32 while ensuring airtightness with the seal 58. The transfer screw 32 has a spiral shape, and a scraping bar 59 is inserted therein. By adopting such a configuration, the carbon sticking to the screw 32 is scraped off by the scraping bar 59 so that the carbon sticking to the screw 32 itself is reduced, and the rod 33 can be transferred over a long period of time.

  (Third Embodiment) The third embodiment of the present invention is also characterized by the structure of the gas cooler 7. FIG. 10 is an explanatory view of the structure of the gas cooler 7 in the waste pyrolysis processing system of the third embodiment of the present invention, and FIG. 11 is a front view of the scraper. In FIG. 10, a scraper 60 for scraping off deposits is inserted into the smoke tube boiler heat transfer tube 46 of the gas cooler 7, and a wiping nozzle 61 is provided at the gas cooler bottom 16. The scraper 60 is driven by a drive motor 62, and is attached by being sealed off from the outside by a seal 63. The soot 65 collected at the bottom of the lower smoke chamber 64 is blown off by the soot removal nozzle 61 and sent to the cooling screw 34 side in the subsequent stage.

  Steam generated by itself is used for steaming, and a valve 66 for flowing a small amount of steam at all times and a control valve 67 for flowing a large amount of steam intermittently when brushing are attached. With this configuration, a small amount of steam is constantly flowing, so that compared to the case where only a large amount of steam is flowed intermittently, the brushed nozzle will not be clogged and the thermal shock will be lower, thus preventing damage to the nozzle. Can do.

The block diagram of a general waste pyrolysis processing system. The layout figure which shows the equipment arrangement | positioning of the waste pyrolysis processing system of the 1st Embodiment of this invention. Sectional drawing of the structure of the gas reformer and gas cooler in the waste thermal decomposition treatment system of the said 1st Embodiment. Sectional drawing of the structure of the bag filter in the waste thermal decomposition treatment system of the said 1st Embodiment. Sectional drawing of the structure of the gas cleaning apparatus in the waste thermal decomposition treatment system of the said 1st Embodiment. Sectional drawing of the soot discharge mechanism of the double damper structure in the said 1st Embodiment. Explanatory drawing of operation | movement of the said soot discharging mechanism. Sectional drawing of the structure of the front | former part of the gas cooler in the waste pyrolysis processing system of the 2nd Embodiment of this invention. Explanatory drawing of the transfer screw of the bottom part of the gas cooler in the waste thermal decomposition treatment system of the said 2nd Embodiment. Sectional drawing of the structure of the gas cooler in the waste pyrolysis processing system of the 3rd Embodiment of this invention. The proof figure of the scraper of the 3rd Embodiment of this invention.

Explanation of symbols

6 Gas reformer 7 Gas cooler 8 Bag filter 9 Gas cleaning device 13 Pre-reaction tower 14 Post-reaction tower 17 Quencher device 20 Filter cloth 21 Cooler 22 Gas cleaning tower 23 Inlet piping 27 Scraper 32 Transfer screw 34 Cooling screw 35 Discharge mechanism 37 Cooling screw 38 Discharge mechanism 47 Upper can plate 52 Suction cone 53 Discharge nozzle 55, 56 Valve 59 Scraping rod 60 Scraper 61 Discharge nozzle 80 Discharge mechanism 81 Side wall 82 Support column 83 Rotating movable part 84 Upper opening / closing cover 85 Lower opening / closing cover

Claims (5)

A pyrolysis furnace for thermally decomposing processed materials such as waste;
A gas reformer that accepts an organic polymer gas generated by thermal decomposition of the object to be processed in the pyrolysis furnace, reforms it into a low-molecular combustible gas by high-temperature gas reforming treatment, and discharges it. When,
A gas cooler that receives and cools the combustible gas discharged from the gas reformer, and discharges the combustible gas;
In a waste pyrolysis system comprising a gas purification device that receives and purifies the combustible gas discharged from the gas cooler, removes impurities, and discharges the purified combustible gas,
The gas reformer includes a pre-reaction tower and a post-reaction tower, and has a concave shape by connecting lower portions of the pre-reaction tower and the post-reaction tower, and the upper part of the pre-reaction tower is the pyrolysis furnace. The organic polymer gas is received and a pyrolysis burner is attached in the vicinity of the upper part of the pre-reaction tower, and the discharge part at the upper part of the post-reaction tower is connected to the gas cooler. The low-molecular combustible gas modified by the high-temperature gas reforming process in the gas reformer is discharged to the gas cooler,
The gas cooler is equipped with a heat transfer tube for gas cooling, and a front stage part for cooling the gas by passing the inside of the heat transfer pipe from the top to the bottom through the combustible gas, and a rear stage part composed of a quencher device, Are connected in such a manner that the lower portions thereof communicate with each other, and the upper portion of the front stage portion is connected to the low molecular combustible gas discharge portion of the gas reformer, and the upper portion of the quencher device. Is connected to the gas purification apparatus.   2. The waste heat according to claim 1, wherein a carbon ash removal mechanism including a transfer screw, a cooling screw, and a discharge mechanism is provided at a bottom portion where the front and rear stages of the gas cooler communicate with each other. Disassembly processing system. The upper part of the quencher device is connected to the middle part of a bag filter installed vertically, and the quencher is placed inward from the outer surface of the vertical filter cloth provided above the middle part in the bag filter. The waste pyrolysis treatment system according to claim 1 or 2, wherein gas from the apparatus is flowed and the gas flows toward an upper part.   A smoke tube boiler is installed at the front stage of the gas cooler, a suction cone is provided on the upper can plate of the smoke tube boiler, and a wiping nozzle for spraying steam on the suction cone is slightly inserted into the suction cone. The waste thermal decomposition treatment system according to any one of claims 1 to 3, wherein   The waste pyrolysis processing system according to claim 4, wherein a small amount of steam is always supplied to the soaking nozzle of the gas cooler, and a large amount of steam is intermittently supplied when sowing.

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