CN113970100B

CN113970100B - Hazardous waste pyrolysis incineration system and hazardous waste pyrolysis incineration method

Info

Publication number: CN113970100B
Application number: CN202010709504.6A
Authority: CN
Inventors: 李谦; 周浩宇; 叶恒棣; 魏进超; 沈维民; 陈思墨; 刘前; 王业峰
Original assignee: Zhongye Changtian International Engineering Co Ltd
Current assignee: Zhongye Changtian International Engineering Co Ltd
Priority date: 2020-07-22
Filing date: 2020-07-22
Publication date: 2023-06-23
Anticipated expiration: 2040-07-22
Also published as: CN113970100A

Abstract

The invention discloses a hazardous waste pyrolysis incineration system which comprises a crushing and screening device, a pyrolysis furnace and an incinerator. The material conveying pipe is connected to a feed inlet of the crushing and screening device. The undersize discharge port of the crushing and screening device is connected to the feed inlet of the pyrolysis furnace through a second pipeline. The discharge port of the pyrolysis furnace is connected to the feed port of the incinerator through a third pipeline. And the discharge port of the incinerator discharges residues through a fifth pipeline. And a discharge hole on the screen of the crushing and screening device is communicated with the third pipeline through a fourth pipeline. The system carries out anaerobic (or anoxic) pyrolysis and oxygen-enriched incineration on the materials, thereby realizing the purposes of complete pyrolysis and complete incineration of the organic hazardous waste; the pyrolysis effect is improved. The phenomenon of ring formation caused by subsequent incineration is effectively prevented, and the generation of dioxin is reduced.

Description

Hazardous waste pyrolysis incineration system and hazardous waste pyrolysis incineration method

Technical Field

The invention relates to an organic hazardous waste pyrolyzate incineration treatment process system, in particular to a hazardous waste pyrolysis incineration system and a hazardous waste pyrolysis incineration method, and belongs to the technical field of comprehensive utilization of resources.

Background

The incineration kiln can be used for incinerating organic hazardous wastes, is a rotary incineration kiln, and is an important component device of a hazardous waste incineration system. The organic hazardous waste contains organic matters and has a certain heat value, so that the organic hazardous waste is suitable for being disposed in an incineration mode, the purpose of reducing the volume of the hazardous waste can be achieved, and the heat energy in the waste can be recovered, so that the comprehensive utilization of resources is achieved.

The existing general hazardous waste rotary kiln is shown in fig. 1, wherein the device 1 in fig. 1 is a rotary kiln head; the device 2 is a kiln body. The device 12 is a hazardous waste feed port; the device 13 is an air inlet; the device 21 is a discharge port; in actual production, in order to enable the material to normally advance in the rotation process, a certain inclination angle is arranged on the rotary kiln, and the rotary kiln is required to be high and low in left and right as shown in fig. 1.

The incineration materials are pushed into the rotary kiln from a feed inlet of the device 12 by a hydraulic push rod (not shown in the figure), air enters the rotary kiln from an air inlet channel of the device 13, the materials are dried, pyrolyzed and ignited rapidly in a high-temperature environment, the incineration materials are continuously rolled and gradually move towards the kiln tail under the rotation of the rotary kiln, the materials are combusted in the rolling and moving process, and residues and smoke are discharged out of the kiln body from a discharge outlet of the device 21.

In the prior art, the rotary kiln generally maintains the combustion temperature of 800-900 ℃, the combustible components of dangerous wastes and air enter the rotary kiln from the kiln head, and the dangerous wastes are quickly dried, pyrolyzed and ignited after entering the rotary kiln, and are fully contacted with the air and fully combusted under the rotation of the rotary kiln. However, the existing rotary kiln has unsatisfactory pyrolysis effect, is easy to cause incomplete subsequent incineration, is likely to increase the generation of dioxin, even needs to consume a large amount of fuel additionally, and simultaneously is easy to cause uneven temperature distribution of the incinerator along the kiln body direction, so that the incineration efficiency is low, and the phenomenon of looping easily occurs at a high temperature section, thereby influencing normal production.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a separated organic hazardous waste pyrolysis and incineration system, which realizes the purposes of complete pyrolysis and complete incineration of the organic hazardous waste by adopting two furnace bodies to respectively carry out anaerobic (or anoxic) pyrolysis and oxygen-enriched incineration on materials; meanwhile, the combustible pyrolysis gas obtained by pyrolysis is used as an incineration fuel, and high-temperature flue gas generated by incineration is used as a heat source in the pyrolysis process, so that comprehensive utilization of resources is realized. The invention further creates an anaerobic or anoxic pyrolysis environment for pyrolysis by separating the pyrolysis zone from the heat source radiation zone, thereby improving the pyrolysis effect. Thereby preventing the subsequent burning from generating ring forming phenomenon and reducing the generation of dioxin.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

according to a first embodiment of the present invention, there is provided a hazardous waste pyrolysis incineration system comprising a pulverizing and screening device, a pyrolysis furnace, and an incinerator. The material conveying pipe is connected to a feed inlet of the crushing and screening device. The undersize discharge port of the crushing and screening device is connected to the feed inlet of the pyrolysis furnace through a second pipeline. The upper screen discharge port of the crushing and screening device is connected to the feed inlet of the incinerator through a fourth pipeline. The discharge port of the pyrolysis furnace is connected to the feed port of the incinerator or to a fourth pipeline through a third pipeline. And the discharge port of the incinerator discharges residues through a fifth pipeline.

Preferably, the pyrolysis gas outlet of the pyrolysis furnace is connected to the gas inlet of the incinerator through a seventh pipe. The exhaust port of the incinerator is connected to the flue gas inlet of the pyrolysis furnace through a sixth pipeline.

Preferably, the pyrolysis furnace is a rotary kiln pyrolysis furnace, and comprises a kiln head, a kiln body and a kiln tail. The kiln head is provided with a material inlet channel and a smoke inlet channel. And a residue outlet channel, a flue gas outlet channel and a pyrolysis gas outlet channel are arranged on the kiln tail. The kiln body is of a hollow cavity structure, and a kiln head stacking area is arranged between the kiln body and the kiln head. And a kiln tail stacking area is arranged between the kiln body and the kiln tail. The kiln head stacking area is communicated with the material inlet channel. And the kiln tail stacking area is communicated with the residue outlet channel and the pyrolysis gas outlet channel.

Preferably, the kiln body comprises an outer wall and an inner cavity. The outer wall is formed by a furnace lining. The inner cavity is composed of a smoke flow chamber and a material flow chamber. The material flow chamber is located between the flue gas flow chamber and the furnace lining. One end of the smoke flow chamber passes through the kiln head stacking area and then is communicated with the smoke inlet channel, and the other end of the smoke flow chamber passes through the kiln tail stacking area and then is communicated with the smoke outlet channel. One end of the material flow chamber is communicated with the kiln head stacking area, and the other end of the material flow chamber is communicated with the kiln tail stacking area.

Preferably, the system further comprises a waste heat utilization device and a pyrolysis gas utilization device. The flue gas outlet channel of the pyrolysis furnace is connected to the waste heat utilization device through an eighth pipeline. And the seventh pipeline is provided with a bypass pipeline which is connected to the pyrolysis gas utilization device.

Preferably, the system further comprises a pyrolysis gas bypass conduit. The incinerator is provided with a pyrolysis gas inlet. The pyrolysis gas branch pipeline is connected to the furnace body of the incinerator. The seventh pipeline is communicated with a pyrolysis gas inlet of the incinerator through a pyrolysis gas branch pipeline.

Preferably, the system comprises a plurality of said pyrolysis gas branch conduits. The incinerator is provided with a plurality of pyrolysis gas inlets, and each pyrolysis gas branch pipeline is connected to one pyrolysis gas inlet. The number of the pyrolysis gas branch pipelines is 1-20, preferably 3-15, more preferably 5-10.

Preferably, a plurality of material flow chambers are arranged in the kiln body. A plurality of said material flow chambers are circumferentially arranged between the furnace lining and the flue gas flow chamber.

Preferably, the number of the plurality of material flow chambers is 1 to 10, preferably 2 to 8, more preferably 3 to 5.

Preferably, the incinerator is further provided with a combustion air pipeline and a fuel pipeline.

Preferably, the material flow chamber and the smoke flow chamber are not communicated with each other. Any one of the material flow chambers and the smoke flow chamber are isolated by a heat exchange partition board. The heat exchange partition plate is an efficient heat exchange plate.

Preferably, the pyrolysis furnace is of an inclined design with a high kiln head and a low kiln tail, and the inclination angle is 3-60 degrees, preferably 5-45 degrees, and more preferably 8-30 degrees.

According to a second embodiment of the present invention, there is provided a hazardous waste pyrolysis incineration method or a method for pyrolysis incineration of hazardous waste using the system described in the first embodiment, the method comprising the steps of:

1) According to the trend of the materials, after the dangerous waste is crushed and sieved by the crushing and sieving device, the undersize fine materials are conveyed into a material flow chamber of the pyrolysis furnace for pyrolysis treatment. And conveying pyrolysis residues after pyrolysis and coarse materials on a screen of the crushing and screening device into an incinerator for incineration treatment. The incineration residue after the incineration is completed is discharged through a fifth pipe.

2) According to the trend of the flue gas, the high-temperature flue gas of the incinerator is conveyed into a flue gas flow chamber in the pyrolysis furnace through a sixth pipeline and supplies heat required by material pyrolysis for a material flow chamber arranged outside the flue gas flow chamber. Pyrolysis gas generated by pyrolysis in the pyrolysis furnace is conveyed into the incinerator through a seventh pipeline to provide fuel for material incineration, and the pyrolysis gas circulates in this way.

3) In the pyrolysis furnace, materials are firstly put into a kiln head stacking area through a material inlet channel. And then, uniformly distributing the materials in the kiln head stacking area into a plurality of material flowing chambers through rotation of the kiln body to carry out pyrolysis (an anaerobic or anoxic environment). And meanwhile, pyrolysis residues after pyrolysis treatment in the material flow chambers are discharged to a kiln tail stacking area and then discharged through a residue outlet channel. In the process, high-temperature flue gas entering the flue gas flow chamber from the flue gas inlet channel continuously irradiates heat to the material flow chamber to complete pyrolysis treatment of the material.

Preferably, the method further comprises step 4): when the pyrolysis temperature is too low, the fuel is supplemented by the fuel pipeline to perform incineration treatment so as to improve the temperature of the high-temperature flue gas. When pyrolysis temperature is too high, increase material is put in and is carried partial pyrolysis gas to pyrolysis gas utilization device through bypass pipeline simultaneously and recycle. And finally, conveying the flue gas subjected to pyrolysis treatment to a waste heat utilization device for waste heat recycling.

Preferably, the feeding amount of the pyrolysis furnace is 800-6000kg/h, preferably 1200-5000kg/h, and more preferably 1500-4000kg/h.

Preferably, the rotation speed of the pyrolysis furnace is 1-6r/min, preferably 1.5-5r/min, more preferably 2-4r/min.

Preferably, the particle size of the undersize material is 15mm or less, preferably 12mm or less, more preferably 10mm or less.

Preferably, the particle size of the coarse material on the screen is 15mm or more, preferably 12mm or more, more preferably 10mm or more.

In the prior art, the existing rotary incinerator device is usually provided with only one air inlet, namely all air required by material incineration enters the rotary kiln from the kiln head, and the air quantity can be regulated only by the air flow rate in the kiln head. This has two disadvantages: firstly, air just enters the rotary kiln, an oxygen-enriched section is formed at the inlet section of the rotary kiln, the oxygen in the section of the rotary kiln is sufficient and violently combusted, the temperature is higher, the oxygen in the rear section of the rotary kiln is insufficient, the temperature is rapidly reduced, and a temperature distribution structure with high forward temperature (higher than an ideal temperature value Ta) and low backward temperature (lower than the ideal temperature value Ta) of the rotary kiln is formed. The normal combustion temperature Ta of the materials in the rotary kiln is generally 850-900 ℃, when the high temperature in the rotary kiln is too high, ash slag is easy to melt, the rear temperature is too low, and the melted ash slag is condensed, so that the phenomenon of ring formation is caused. Secondly, because the solid material is not uniformly contacted with air, partial residues cannot be fully combusted, and the generation of dioxin is possibly increased.

Further, in the prior art, heat sources required by the pyrolysis section are all from heat radiation generated by combustion in the rear of the rotary kiln, and meanwhile, because kiln head air inlet is adopted, anaerobic (or anoxic) pyrolysis cannot be realized by pyrolysis in the front of the rotary kiln, so that the burning phenomenon occurs in the front of the rotary kiln, and the pressure of subsequent burning treatment is not fully increased by pyrolysis. Meanwhile, a great amount of oxygen is consumed due to the burning phenomenon in the front of the rotary kiln, so that the oxygen flowing into the rear for burning treatment is insufficient, the burning of the subsequent burning treatment is insufficient, and a great amount of dioxin is easy to generate. In the prior art, partial pyrolysis incineration technology is adopted to assist combustion by adopting a mode of air intake at the middle and rear parts of the rotary kiln to supplement oxygen in the later half-process incineration stage, so as to solve the problem of incomplete incineration. Although the effect that takes this measure to obtain is better, add the air supply system in addition, improved production input and maintenance cost, also lead to the rotary kiln to follow the inhomogeneous temperature distribution of kiln body direction simultaneously easily for incineration efficiency is not high, and the high temperature section easily takes place the phenomenon of looping, influences normal production.

In the invention, an organic hazardous waste treatment process for dividing the existing integral incineration rotary kiln into two kilns for pyrolysis and incineration is provided, and the pyrolysis and the incineration of materials are respectively realized in two kiln bodies, namely, a pyrolysis section and an incineration section are relatively independent. The high-temperature flue gas generated by incineration in the incinerator is introduced into the pyrolysis furnace through a pipeline to provide heat for pyrolysis of materials. And the combustible pyrolysis gas generated by pyrolysis in the pyrolysis furnace is conveyed into the incinerator through a pipeline to be burnt as fuel.

In order to effectively ensure an anaerobic or anoxic (a small amount of air enters when kiln head feeding is considered) environment of a pyrolysis section, the kiln head of the pyrolysis furnace is respectively provided with a material inlet channel and a smoke inlet channel which are not communicated with each other, and a material flow chamber and a smoke flow chamber which are not communicated with each other are arranged in the inner cavity of a kiln body of the pyrolysis furnace. The material flow chamber is provided with a plurality of and is the outside that surrounds the setting at flue gas flow chamber, baffle between material flow chamber and the flue gas flow chamber adopts high-efficient heat transfer material, and then improves the heat in the high temperature flue gas in the flue gas flow chamber and gets into the material flow chamber and carry out pyrolysis to the material as far as possible in the radiation. Through the independent design of the material flow chamber and the smoke flow chamber which are not communicated with each other, the anaerobic pyrolysis environment of the pyrolysis section is ensured as much as possible (the smoke flow contained in the smoke is prevented from entering the pyrolysis section). Meanwhile, in order to further improve the pyrolysis effect, the outer wall of the kiln body of the pyrolysis furnace adopts a furnace lining (the thickness of the furnace lining is 3-50cm, preferably 5-30cm, more preferably 8-15 cm) which is made of materials with heat preservation effect and has a considerable thickness, and the furnace lining completely covers the outer parts of the material flow chamber and the smoke flow chamber, so that heat loss is reduced. And also avoids excessive heat radiation from being discharged to the outside.

In the present invention, the organic hazardous waste material before entering pyrolysis is required to be subjected to crushing and screening treatment, wherein only undersize fine material (the particle size of which is 15mm or less, preferably 12mm or less, more preferably 10mm or less) is conveyed to a pyrolysis furnace for pyrolysis, and undersize coarse material (the particle size of which is 15mm or more, preferably 12mm or more, more preferably 10mm or more) is conveyed to an incinerator together with pyrolysis residues formed after pyrolysis of the undersize fine material for incineration treatment. The small-particle material has large specific surface area and high pyrolysis efficiency, and enters a pyrolysis furnace for pyrolysis. The pyrolysis furnace is an external heating type rotary kiln, a heat source for pyrolysis is provided by high-temperature flue gas, the high-temperature flue gas exchanges heat with materials through pipe walls (plate walls made of high-efficiency heat exchange materials), the materials are pyrolyzed under the condition of isolating air, combustible gas can be separated out, and residual pyrolysis residues are discharged from the pyrolysis furnace. Because the pyrolysis furnace can not ensure that the organic matters in the materials are fully reacted, the pyrolysis residues still have more organic combustible matters, and therefore, the pyrolysis residues are continuously sent into the incinerator for further incineration. The pyrolysis efficiency of the large-particle materials in the pyrolysis furnace is low, so that the large-particle materials are directly mixed with pyrolysis residues and then sent into an incinerator for incineration.

In the invention, pyrolysis residues are fully combusted and decomposed in the incinerator, the final bottom residues are discharged from the incinerator body for other treatment, meanwhile, the combustible pyrolysis gas generated by the pyrolysis furnace is independently pumped out and sent into the incinerator, and the pyrolysis gas is introduced into the incinerator along the kiln body in a grading way by adopting the design of a plurality of pyrolysis gas branch pipelines, and then air is supplemented from the kiln head of the incinerator to ensure full combustion. And the temperature of the high-temperature flue gas after heat exchange in the pyrolysis furnace is reduced to become low-temperature flue gas. The low-temperature flue gas enters a subsequent waste heat utilization device (such as a waste heat boiler) to recover heat, and then enters a flue gas purification system to be purified and then discharged.

In the invention, in order to prevent the phenomenon of air flow backflow, a valve or an induced draft fan can be arranged on the flue gas conveying pipeline and the pyrolysis gas conveying pipeline according to actual needs. Not only can prevent the air flow from flowing back, but also can improve the air flow conveying efficiency.

In the invention, when the system is adopted to carry out the organic hazardous pyrolysis incineration process, the pyrolysis and incineration proceeding degree can be judged by observing pyrolysis residues or incineration residues or observing the temperatures of a pyrolysis zone and an incineration zone, and then corresponding measures are adopted to lead the pyrolysis and the incineration to proceed smoothly: for example: when the temperature of the pyrolysis section is too low, the heat of the high-temperature flue gas radiation is insufficient, and the temperature of the high-temperature flue gas can be increased by adding fuel to the incinerator (all pyrolysis gas is conveyed to the incinerator at the moment); when the temperature of the pyrolysis furnace is too high, the temperature of the high-temperature flue gas is reduced by increasing the flow of the pyrolysis gas delivered to the incinerator or reducing the flow of the pyrolysis gas, and meanwhile, the redundant pyrolysis gas is delivered to other pyrolysis gas utilization devices for treatment and utilization.

According to the invention, the kiln head stacking area is arranged, materials put in through the material inlet channel can be uniformly distributed into each material flowing cavity for pyrolysis treatment in the process of rotating the kiln body, and under the condition of a certain high-temperature flue gas temperature and flow rate, the material put-in amount and pyrolysis temperature of each material flowing cavity are kept consistent, so that the material pyrolysis degree of each material flowing cavity is consistent, the optimal pyrolysis effect can be achieved (only the material put-in amount and the flue gas temperature are required to be controlled), and the phenomenon that the pyrolysis temperature of the pyrolysis cavity with less materials and too low pyrolysis temperature of the pyrolysis cavity with too much materials is generated under the same flue gas temperature due to uneven material distribution of each material flowing cavity is avoided. Meanwhile, a kiln tail stacking area is arranged at the kiln tail, pyrolysis residues and hot gas in each material flow chamber can be combined together, then the pyrolysis residues are discharged from a discharge hole at the bottom of the kiln tail stacking area, and the pyrolysis gas is discharged from an exhaust hole at the upper part of the kiln tail stacking area. Realizes the centralized separation and discharge of pyrolysis residues and pyrolysis gas.

In the invention, the furnace length and the outer diameter of the pyrolysis furnace can be designed according to actual working conditions. For example, the pyrolysis furnace has a furnace length of 3 to 30m, preferably 5 to 25m, more preferably 8 to 20m. The external diameter of the pyrolysis furnace is 1-10m, preferably 2-8m, more preferably 3-8m. The present invention is merely illustrative of the preferred design and should not be construed as limiting the scope of the invention.

Further, the feeding amount of the pyrolysis furnace is 800-6000kg/h, preferably 1200-5000kg/h, and more preferably 1500-4000kg/h. The rotational speed of the pyrolysis furnace is 1-6r/min, preferably 1.5-5r/min, more preferably 2-4r/min.

In the invention, the pyrolysis degree of the high-volatile garbage material in the pyrolysis furnace is determined by the residence time of the high-volatile garbage material in the pyrolysis furnace, and the residence time of the organic hazardous waste garbage in the pyrolysis furnace is only determined by the rotating speed of the pyrolysis furnace under the condition that the structural design parameters of the pyrolysis furnace body are determined. If the residence time of the garbage in the pyrolysis furnace is too short, the garbage is insufficiently pyrolyzed, and the effect of segmented pyrolysis incineration cannot be achieved; if the residence time is too long, the rotating speed of the pyrolysis furnace is too low, the organic hazardous waste is not turned sufficiently, and the pyrolysis is also caused to be insufficient and uneven. The reasonable rotating speed of the pyrolysis furnace needs to ensure the sufficient residence time of the garbage and enable the garbage to be fully turned, and on the basis, the specific value of the rotating speed is positively related to the garbage amount entering the furnace. The preferred recommended speeds and feeds for pyrolysis furnaces having a furnace length of 10 meters and an outer diameter of 3 meters are exemplified herein as set forth in the following table (which is not intended to be limiting in this regard):

compared with the prior art, the invention has the following beneficial technical effects:

1. according to the system, the pyrolysis section and the incineration section adopt a separated design, high-temperature flue gas of the incineration section is used as a heat source of the pyrolysis section, and pyrolysis gas of the pyrolysis section is used for assisting combustion of the incineration section to obtain high-temperature flue gas, so that comprehensive utilization of resources is realized, and production investment cost is reduced.

2. In the pyrolysis furnace, the material flow area and the high-temperature smoke flow area are not communicated with each other, heat exchange is performed by adopting a pipe wall heat exchange mode, so that pyrolysis of materials is completed, meanwhile, the anaerobic or anoxic environment of the material flow area is effectively ensured, the pyrolysis effect is improved, and the subsequent incineration pressure is reduced.

3. The pyrolysis incineration system provided by the invention has the advantages that the structure is simple, the operation is easy, the process flow of the pyrolysis incineration treatment of the organic hazardous waste heat by adopting the system is short, the pyrolysis incineration efficiency is high, and the pyrolysis incineration sectional operation is adopted, so that the pyrolysis is more sufficient, the incineration is more thorough, and the occurrence of the ring formation phenomenon in a kiln and the generation of dioxin are effectively prevented.

Drawings

Fig. 1 is a diagram of a pyrolysis incineration device of a rotary kiln in the prior art.

FIG. 2 is a cross-sectional view of a rotary kiln A-A of the prior art.

FIG. 3 is a block diagram of the hazardous waste pyrolysis incineration system according to the present invention.

FIG. 4 is a schematic diagram of a pyrolysis furnace according to the present invention.

FIG. 5 is a cross-sectional view of a pyrolysis furnace A-A according to the present invention.

FIG. 6 is a cross-sectional view of a pyrolysis furnace B-B according to the present invention.

FIG. 7 is a cross-sectional view of a pyrolysis furnace C-C according to the present invention.

Reference numerals: 1: crushing and screening device; 2. a pyrolysis furnace; 3. an incinerator; 4: a waste heat utilization device; 5: a pyrolysis gas utilization device; 201: kiln heads; 202: a kiln body; 203: kiln tail; 204: a kiln head stacking area; 205: a kiln tail stacking area; 301: a combustion air duct; 302: a fuel pipe; 20101: a material inlet passage; 20102: a flue gas inlet channel; 20201: a furnace lining; 20202: a flue gas flow chamber; 20203: a material flow chamber; 20204: a heat exchange partition plate; 20301: a residue outlet channel; 20302: a flue gas outlet channel; 20303: a pyrolysis gas outlet channel; l1: a material conveying pipe; l2: a second pipe; l3: a third conduit; l4: a fourth conduit; l5: a fifth pipe; l6: a sixth conduit; l7: a seventh pipe; l8: an eighth conduit; l9: a pyrolysis gas bypass conduit; l10: and a bypass conduit.

Detailed Description

The following examples illustrate the technical aspects of the invention, and the scope of the invention claimed includes but is not limited to the following examples.

A hazardous waste pyrolysis incineration system comprises a crushing and screening device 1, a pyrolysis furnace 2 and an incinerator 3. The material conveying pipe L1 is connected to a feed inlet of the crushing and screening device 1. The undersize discharge port of the crushing and screening device 1 is connected to the feed port of the pyrolysis furnace 2 through a second pipeline L2. The upper screen discharge port of the crushing and screening device 1 is connected to the feed port of the incinerator 3 through a fourth pipeline L4. The discharge port of the pyrolysis furnace 2 is connected to the feed port of the incinerator 3 or to the fourth pipeline L4 through the third pipeline L3. The discharge port of the incinerator 3 discharges residues through a fifth pipeline L5.

Preferably, the pyrolysis gas outlet of the pyrolysis furnace 2 is connected to the gas inlet of the incinerator 3 through a seventh duct L7. The exhaust port of the incinerator 3 is connected to the flue gas inlet of the pyrolysis furnace 2 through a sixth pipe L6.

Preferably, the pyrolysis furnace 2 is a rotary kiln pyrolysis furnace, and includes a kiln head 201, a kiln body 202 and a kiln tail 203. The kiln head 201 is provided with a material inlet channel 20101 and a flue gas inlet channel 20102. The kiln tail 203 is provided with a residue outlet channel 20301, a flue gas outlet channel 20302 and a pyrolysis gas outlet channel 20303. The kiln body 202 is of a hollow cavity structure, and a kiln head stacking area 204 is arranged between the kiln body 202 and the kiln head 201. A kiln tail stockpiling area 205 is arranged between the kiln body 202 and the kiln tail 203. The kiln head stockpiling area 204 is in communication with the material inlet channel 20101. The kiln tail stacker zone 205 communicates with a residue outlet channel 20301 and a pyrolysis gas outlet channel 20303.

Preferably, the kiln body 202 includes an outer wall and an inner cavity. The outer wall is formed by a furnace lining 20201. The inner cavity is formed by a flue gas flow chamber 20202 and a material flow chamber 20203. The material flow chamber 20203 is located between the flue gas flow chamber 20202 and the furnace lining 20201. One end of the flue gas flowing chamber 20202 passes through the kiln head stacking area 204 and then is communicated with the flue gas inlet channel 20102, and the other end of the flue gas flowing chamber 20202 passes through the kiln tail stacking area 205 and then is communicated with the flue gas outlet channel 20302. One end of the material flow chamber 20203 is communicated with the kiln head stockpiling zone 204, and the other end is communicated with the kiln tail stockpiling zone 205.

Preferably, the system further comprises a waste heat utilization device 4 and a pyrolysis gas utilization device 5. The flue gas outlet channel 20302 of the pyrolysis furnace 2 is connected to the waste heat utilization device 4 through an eighth conduit L8. The seventh pipe L7 is connected to the pyrolysis gas utilization unit 5 through a bypass pipe L10.

Preferably, the system further comprises a pyrolysis gas bypass line L9. The incinerator 3 is provided with a pyrolysis gas inlet. The pyrolysis gas branch pipeline L9 is arranged on the furnace body of the incinerator 3. The seventh pipeline L7 is communicated with a pyrolysis gas inlet of the incinerator 3 through a pyrolysis gas branch pipeline L9.

Preferably, the system comprises a plurality of said pyrolysis gas branch ducts L9. The incinerator 3 is provided with a plurality of pyrolysis gas inlets, and each pyrolysis gas branch pipeline L9 is connected to one pyrolysis gas inlet. The number of the pyrolysis gas branch lines L9 is 1 to 20, preferably 3 to 15, more preferably 5 to 10.

Preferably, a plurality of material flow chambers 20203 are provided inside the kiln body 202. A plurality of said material flow chambers 20203 are circumferentially arranged between the furnace lining 20201 and the flue gas flow chambers 20202.

Preferably, the number of the plurality of material flow chambers 20203 is 1 to 10, preferably 2 to 8, more preferably 3 to 5.

Preferably, the incinerator 3 is further provided with a combustion air duct 301 and a fuel duct 302.

Preferably, the material flow chamber 20203 and the flue gas flow chamber 20202 are not in communication with each other. Any one of the material flow chambers 20203 and the flue gas flow chamber 20202 are isolated by a heat exchange partition 20204. The heat exchange spacer 20204 is a high-efficiency heat exchange plate.

Preferably, the pyrolysis furnace 2 is of an inclined design with a high kiln head 201 and a low kiln tail 203, the inclination angle being 3-60 °, preferably 5-45 °, more preferably 8-30 °.

A method of hazardous waste pyrolysis incineration or a method of hazardous waste pyrolysis incineration using a hazardous waste pyrolysis incineration system, the method comprising the steps of:

1) According to the trend of the materials, after the dangerous waste is crushed and sieved by the crushing and sieving device 1, the undersize fine materials are conveyed into a material flow chamber 20203 of the pyrolysis furnace 2 for pyrolysis treatment. And the pyrolysis residues after pyrolysis and the coarse materials on the screen of the crushing and screening device 1 are conveyed into the incinerator 3 for incineration treatment. The incineration residue after the incineration is completed is discharged via a fifth pipe L5.

2) According to the trend of the flue gas, the high temperature flue gas of the incinerator 3 is conveyed into the flue gas flow chamber 20202 in the pyrolysis furnace 2 via the sixth pipeline L6 and provides the heat required for pyrolysis of the material to the material flow chamber 20203 arranged outside the flue gas flow chamber 20202. Pyrolysis gas generated by pyrolysis of the pyrolysis furnace 2 is conveyed into the incinerator 3 through a seventh pipeline L7 to provide fuel for material incineration, and the pyrolysis gas circulates.

3) In the pyrolysis furnace 2, material is first fed into the kiln head stacking zone 204 via the material inlet channel 20101. And then the material in the kiln head stacking area 204 is uniformly distributed into a plurality of material flow chambers 20203 for pyrolysis by rotating the kiln body 202. Meanwhile, pyrolysis residues after pyrolysis treatment in a plurality of material flow chambers 20203 are discharged to a kiln tail stacker zone 205 and then discharged through a residue outlet channel 20301. In the process, high-temperature flue gas entering the flue gas flow chamber 20202 from the flue gas inlet channel 20102 continuously carries out heat radiation on the material flow chamber 20203 to finish pyrolysis treatment on the material.

Preferably, the method further comprises step 4): when the pyrolysis temperature is too low, the fuel is supplemented through the fuel pipe 302 to perform incineration treatment to raise the high temperature flue gas temperature. When the pyrolysis temperature is too high, the material feeding is increased, and meanwhile, part of pyrolysis gas is conveyed to the pyrolysis gas utilization device 5 through the bypass pipeline L10 for recycling. And finally, conveying the flue gas subjected to pyrolysis treatment to a waste heat utilization device 4 for waste heat recycling.

Preferably, the feeding amount of the pyrolysis furnace 2 is 800-6000kg/h, preferably 1200-5000kg/h, more preferably 1500-4000kg/h. And/or

Preferably, the rotation speed of the pyrolysis furnace 2 is 1-6r/min, preferably 1.5-5r/min, more preferably 2-4r/min.

Example 1

As shown in fig. 3, a hazardous waste pyrolysis incineration system comprises a crushing and screening device 1, a pyrolysis furnace 2 and an incinerator 3. The material conveying pipe L1 is connected to a feed inlet of the crushing and screening device 1. The undersize discharge port of the crushing and screening device 1 is connected to the feed port of the pyrolysis furnace 2 through a second pipeline L2. The upper screen discharge port of the crushing and screening device 1 is connected to the feed port of the incinerator 3 through a fourth pipeline L4. The discharge port of the pyrolysis furnace 2 is connected to the feed port of the incinerator 3 or to the fourth pipeline L4 through the third pipeline L3. The discharge port of the incinerator 3 discharges residues through a fifth pipeline L5.

Example 2

Example 1 was repeated except that the pyrolysis gas outlet of the pyrolysis furnace 2 was connected to the gas inlet of the incinerator 3 through a seventh duct L7. The exhaust port of the incinerator 3 is connected to the flue gas inlet of the pyrolysis furnace 2 through a sixth pipe L6.

Example 3

Example 2 is repeated, as shown in fig. 4, except that the pyrolysis furnace 2 is a rotary kiln pyrolysis furnace, which includes a kiln head 201, a kiln body 202, and a kiln tail 203. The kiln head 201 is provided with a material inlet channel 20101 and a flue gas inlet channel 20102. The kiln tail 203 is provided with a residue outlet channel 20301, a flue gas outlet channel 20302 and a pyrolysis gas outlet channel 20303. The kiln body 202 is of a hollow cavity structure, and a kiln head stacking area 204 is arranged between the kiln body 202 and the kiln head 201. A kiln tail stockpiling area 205 is arranged between the kiln body 202 and the kiln tail 203. The kiln head stockpiling area 204 is in communication with the material inlet channel 20101. The kiln tail stacker zone 205 communicates with a residue outlet channel 20301 and a pyrolysis gas outlet channel 20303.

Example 4

Example 3 is repeated except that the kiln body 202 includes an outer wall and an inner cavity. The outer wall is formed by a furnace lining 20201. The inner cavity is formed by a flue gas flow chamber 20202 and a material flow chamber 20203. The material flow chamber 20203 is located between the flue gas flow chamber 20202 and the furnace lining 20201. One end of the flue gas flowing chamber 20202 passes through the kiln head stacking area 204 and then is communicated with the flue gas inlet channel 20102, and the other end of the flue gas flowing chamber 20202 passes through the kiln tail stacking area 205 and then is communicated with the flue gas outlet channel 20302. One end of the material flow chamber 20203 is communicated with the kiln head stockpiling zone 204, and the other end is communicated with the kiln tail stockpiling zone 205.

Example 5

Example 4 was repeated except that the system further included a waste heat utilization device 4 and a pyrolysis gas utilization device 5. The flue gas outlet channel 20302 of the pyrolysis furnace 2 is connected to the waste heat utilization device 4 through an eighth conduit L8. The seventh pipe L7 is connected to the pyrolysis gas utilization unit 5 through a bypass pipe L10.

Example 6

Example 5 is repeated except that the system further comprises a pyrolysis gas bypass duct L9. The incinerator 3 is provided with a pyrolysis gas inlet. The pyrolysis gas branch pipeline L9 is arranged on the furnace body of the incinerator 3. The seventh pipeline L7 is communicated with a pyrolysis gas inlet of the incinerator 3 through a pyrolysis gas branch pipeline L9.

Example 7

Example 6 was repeated except that the system included a plurality of said pyrolysis gas branch lines L9. The incinerator 3 is provided with a plurality of pyrolysis gas inlets, and each pyrolysis gas branch pipeline L9 is connected to one pyrolysis gas inlet. The number of the pyrolysis gas branch pipelines L9 is 5.

Example 8

Example 7 is repeated except that a plurality of the material flow chambers 20203 are provided inside the kiln body 202. A plurality of said material flow chambers 20203 are circumferentially arranged between the furnace lining 20201 and the flue gas flow chambers 20202.

Example 9

Example 8 was repeated except that the number of the plurality of material flow chambers 20203 was 4.

Example 10

Example 9 is repeated except that the incinerator 3 is further provided with a combustion air duct 301 and a fuel duct 302.

Example 11

Embodiment 10 is repeated except that the material flow chamber 20203 and the flue gas flow chamber 20202 are not in communication with each other. Any one of the material flow chambers 20203 and the flue gas flow chamber 20202 are isolated by a heat exchange partition 20204. The heat exchange spacer 20204 is a high-efficiency heat exchange plate.

Example 12

Example 11 was repeated except that the pyrolysis furnace 2 was designed with a high kiln head 201 and a low kiln tail 203, the angle of inclination being 10 °.

Claims

1. A hazardous waste pyrolysis incineration system, characterized in that: the system comprises a crushing and screening device (1), a pyrolysis furnace (2) and an incinerator (3); the material conveying pipe (L1) is connected to a feed inlet of the crushing and screening device (1); the undersize discharge port of the crushing and screening device (1) is connected to the feed port of the pyrolysis furnace (2) through a second pipeline (L2); the upper screen discharge port of the crushing and screening device (1) is connected to the feed port of the incinerator (3) through a fourth pipeline (L4); the discharge port of the pyrolysis furnace (2) is connected to the feed port of the incinerator (3) or to the fourth pipeline (L4) through a third pipeline (L3); the discharge port of the incinerator (3) discharges residues through a fifth pipeline (L5);

the pyrolysis furnace (2) is a rotary kiln pyrolysis furnace and comprises a kiln head (201), a kiln body (202) and a kiln tail (203); a material inlet channel (20101) and a smoke inlet channel (20102) are arranged on the kiln head (201); a residue outlet channel (20301), a flue gas outlet channel (20302) and a pyrolysis gas outlet channel (20303) are arranged on the kiln tail (203); the kiln body (202) is of a hollow cavity structure, and a kiln head stacking area (204) is arranged between the kiln body (202) and the kiln head (201); a kiln tail stacking area (205) is arranged between the kiln body (202) and the kiln tail (203); the kiln head stacking area (204) is communicated with the material inlet channel (20101); the kiln tail stacker zone (205) is in communication with a residue outlet channel (20301) and a pyrolysis gas outlet channel (20303).

2. The system according to claim 1, wherein: the pyrolysis gas outlet of the pyrolysis furnace (2) is connected to the gas inlet of the incinerator (3) through a seventh pipeline (L7); the exhaust port of the incinerator (3) is connected to the flue gas inlet of the pyrolysis furnace (2) through a sixth pipeline (L6).

3. The system according to claim 2, wherein: the kiln body (202) comprises an outer wall and an inner cavity; the outer wall is formed by a furnace lining (20201); the inner cavity is formed by a smoke flow chamber (20202) and a material flow chamber (20203); the material flow chamber (20203) is located between the flue gas flow chamber (20202) and the furnace lining (20201); one end of the flue gas flowing chamber (20202) passes through the kiln head stacking area (204) and then is communicated with the flue gas inlet channel (20102), and the other end of the flue gas flowing chamber passes through the kiln tail stacking area (205) and then is communicated with the flue gas outlet channel (20302); one end of the material flow chamber (20203) is communicated with the kiln head stacking area (204), and the other end of the material flow chamber is communicated with the kiln tail stacking area (205).

4. A system according to claim 3, characterized in that: the system also comprises a waste heat utilization device (4) and a pyrolysis gas utilization device (5); the flue gas outlet channel (20302) of the pyrolysis furnace (2) is connected to the waste heat utilization device (4) through an eighth pipeline (L8); and a bypass pipeline (L10) is led out of the seventh pipeline (L7) and is connected to the pyrolysis gas utilization device (5).

5. The system according to claim 4, wherein: the system also comprises a pyrolysis gas branch pipeline (L9); the incinerator (3) is provided with a pyrolysis gas inlet; the pyrolysis gas branch pipeline (L9) is connected to the furnace body of the incinerator (3); the seventh pipeline (L7) is communicated with a pyrolysis gas inlet of the incinerator (3) through a pyrolysis gas branch pipeline (L9).

6. The system according to claim 5, wherein: the system comprises a plurality of pyrolysis gas branch pipelines (L9), wherein a plurality of pyrolysis gas inlets are arranged on the incinerator (3), and each pyrolysis gas branch pipeline (L9) is connected to one pyrolysis gas inlet; the number of the pyrolysis gas branch pipelines (L9) is 1-20.

7. The system according to claim 6, wherein: the number of the pyrolysis gas branch pipelines (L9) is 3-15.

8. The system according to claim 7, wherein: the number of the pyrolysis gas branch pipelines (L9) is 5-10.

9. The system according to any one of claims 3-8, wherein: a plurality of material flow chambers (20203) are arranged inside the kiln body (202); a plurality of material flow chambers (20203) are arranged around the furnace lining (20201) and the flue gas flow chambers (20202).

10. The system according to claim 9, wherein: the number of the plurality of material flow chambers (20203) is 1-10.

11. The system according to claim 10, wherein: the number of the plurality of material flow chambers (20203) is 2-8.

12. The system according to claim 11, wherein: the number of the plurality of material flow chambers (20203) is 3-5.

13. The system according to any one of claims 3-8, 10-12, wherein: the material flow chamber (20203) and the smoke flow chamber (20202) are not communicated with each other; any one material flow chamber (20203) and the flue gas flow chamber (20202) are isolated by a heat exchange partition board (20204); the heat exchange partition plate (20204) is an efficient heat exchange plate.

14. The system according to claim 9, wherein: the material flow chamber (20203) and the smoke flow chamber (20202) are not communicated with each other; any one material flow chamber (20203) and the flue gas flow chamber (20202) are isolated by a heat exchange partition board (20204); the heat exchange partition plate (20204) is an efficient heat exchange plate.

15. The system according to any one of claims 1-8, 10-12, 14, wherein: the incinerator (3) is also provided with a combustion air pipeline (301) and a fuel pipeline (302); and/or

The pyrolysis furnace (2) is of an inclined design with a high kiln head (201) and a low kiln tail (203), and the inclination angle is 3-60 degrees.

16. The system according to claim 9, wherein: the incinerator (3) is also provided with a combustion air pipeline (301) and a fuel pipeline (302); and/or

17. The system according to claim 13, wherein: the incinerator (3) is also provided with a combustion air pipeline (301) and a fuel pipeline (302); and/or

18. The system according to claim 15, wherein: the inclination angle is 5-45 degrees.

19. The system according to claim 16, wherein: the inclination angle is 5-45 degrees.

20. The system according to claim 17, wherein: the inclination angle is 5-45 degrees.

21. The system according to any one of claims 18-20, wherein: the inclination angle is 8-30 degrees.

22. A method of pyrolysis incineration of hazardous waste using the system according to any one of claims 1 to 21, characterised in that: the method comprises the following steps:

1) according to the trend of the materials, after the dangerous waste is crushed and sieved by a crushing and sieving device (1), the undersize fine materials are conveyed into a material flow chamber (20203) of a pyrolysis furnace (2) for pyrolysis treatment; the pyrolysis residue after pyrolysis and the coarse materials on the screen of the crushing and screening device (1) are conveyed into an incinerator (3) together for incineration treatment; discharging incineration residue after the incineration is completed through a fifth pipeline (L5);

2) According to the trend of the flue gas, the high-temperature flue gas of the incinerator (3) is conveyed into a flue gas flow chamber (20202) in the pyrolysis furnace (2) through a sixth pipeline (L6) and supplies heat required by material pyrolysis for a material flow chamber (20203) arranged outside the flue gas flow chamber (20202); pyrolysis gas generated by pyrolysis of the pyrolysis furnace (2) is conveyed into the incinerator (3) through a seventh pipeline (L7) to provide fuel for material incineration, and the pyrolysis gas circulates in turn;

3) In the pyrolysis furnace (2), materials are firstly put into a kiln head stacking area (204) through a material inlet channel (20101); then, the material in the kiln head stacking area (204) is uniformly distributed into a plurality of material flow chambers (20203) through the rotation of the kiln body (202) for pyrolysis; simultaneously, the pyrolysis residues after pyrolysis treatment in a plurality of material flow chambers (20203) are discharged to a kiln tail stacker zone (205) and then discharged from a residue outlet channel (20301); in the process, high-temperature flue gas entering the flue gas flow chamber (20202) from the flue gas inlet channel (20102) continuously carries out heat radiation on the material flow chamber (20203) to finish pyrolysis treatment on the material.

23. The method as claimed in claim 22, wherein: the method further comprises step 4): when the pyrolysis temperature is too low, the fuel is supplemented by a fuel pipeline (302) to perform incineration treatment so as to increase the temperature of the high-temperature flue gas; when the pyrolysis temperature is too high, the material throwing is increased, and meanwhile, part of pyrolysis gas is conveyed to a pyrolysis gas utilization device (5) through a bypass pipeline (L10) for recycling; and finally, conveying the flue gas subjected to pyrolysis treatment to a waste heat utilization device (4) for waste heat recycling.

24. The method according to claim 22 or 23, characterized in that: the feeding amount of the pyrolysis furnace (2) is 800-6000kg/h; and/or

The rotation speed of the pyrolysis furnace (2) is 1-6r/min; and/or

The grain diameter of the undersize material is less than 15mm; and/or

The grain diameter of the coarse material on the sieve is more than or equal to 15mm.

25. The method according to claim 24, wherein: the feeding amount of the pyrolysis furnace (2) is 1200-5000kg/h; and/or

The rotation speed of the pyrolysis furnace (2) is 1.5-5r/min; and/or

The grain diameter of the undersize material is smaller than 12mm; and/or

The grain diameter of the coarse material on the sieve is more than or equal to 12mm.

26. The method according to claim 25, wherein: the feeding amount of the pyrolysis furnace (2) is 1500-4000kg/h; and/or

The rotation speed of the pyrolysis furnace (2) is 2-4r/min; and/or

The grain diameter of the undersize material is smaller than 10mm; and/or

The grain diameter of the coarse material on the sieve is more than or equal to 10mm.