A rotary kiln, a solid waste treatment system and a solid waste treatment method

Abstract

The present invention discloses a rotary kiln, a solid waste treatment system and a solid waste treatment method, relating to the technical field of solid waste treatment. After the solid waste is dried and preheated in the first drum, it is sent into the second drum, where the solid waste undergoes pyrolysis. The pyrolysis liquid generated during the pyrolysis process flows out from the pyrolysis liquid outlet, while the solid pyrolysis carbon part is discharged from the pyrolysis carbon outlet, thereby separating the pyrolysis liquid and the pyrolysis carbon. By discharging the pyrolysis liquid in advance, the situation of coking in the high-temperature environment of the third drum after the pyrolysis liquid enters the third drum is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste treatment equipment, and particularly relates to a rotary kiln, a solid waste treatment system and a solid waste treatment method. Background Art

[0002] General solid waste includes municipal domestic waste, domestic solid waste, sludge, etc., which contain a large amount of organisms and organic matter. When heated in an anaerobic state at 200°C - 500°C or above, it can be converted into pyrolysis gas, tar and other pyrolysis liquids and pyrolysis carbon. The specific process can be divided into the following stages:

[0003] (1) Drying and preheating stage (200°C), water is precipitated;

[0004] (2) Pyrolysis stage (200 - 500°C), generating gases such as combined water, carbon dioxide, carbon monoxide, methane (collectively referred to as pyrolysis gas) and liquids such as tar (collectively referred to as pyrolysis liquid), and at the same time, condensation and synthesis reactions occur, volatiles are precipitated, and solid substances begin to form;

[0005] (3) Drying shrinkage and carbonization stage (500 - 950°C), volatiles are precipitated, a large amount of pyrolysis gas is generated, and carbonization is completed to form pyrolysis carbon.

[0006] Traditional rotary kilns used for solid waste carbonization will generate a large amount of pyrolysis liquids such as tar in the kiln. Especially in the pyrolysis stage (200 - 500°C), a large amount of pyrolysis liquid adheres to the inner wall of the rotary kiln, seriously reducing the heat transfer efficiency of the rotary kiln in this stage and easily causing local high temperatures. At the same time, a large amount of pyrolysis liquid mixed with solid substances easily adheres to the inner wall of the rotary kiln, causing coking and slagging. Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, the present invention provides a rotary kiln that can treat solid waste and prevent the problem that pyrolysis liquid adheres to the inner wall of the rotary furnace during the solid waste treatment process, resulting in a reduction in the heat transfer efficiency of the rotary furnace.

[0008] The present invention also provides a solid waste treatment system.

[0009] The present invention also provides a solid waste treatment method.

[0010] A rotary kiln according to an embodiment of the first aspect of the present invention includes:

[0011] A first drum, provided with a first feed port and a first discharge port;

[0012] A first material transmission mechanism, arranged inside the first drum, for discharging the solid waste entering from the first feed port through the first discharge port;

[0013] A second drum, the second drum is sleeved on the first drum, and the first discharge port is located inside the second drum. The second drum is provided with a pyrolysis liquid outlet and a solid waste outlet, and the pyrolysis liquid of the second drum can flow out from the pyrolysis liquid outlet;

[0014] A second material transmission mechanism, arranged inside the second drum, for discharging the solid waste entering the second drum from the solid waste outlet;

[0015] A third drum, the third drum is sleeved on the second drum, and the solid waste outlet is located inside the third drum. The third drum is provided with a second discharge port;

[0016] A third material transmission mechanism, arranged inside the third drum, for discharging the solid waste entering the third drum from the second discharge port;

[0017] A heating system, used to regulate the temperatures inside the first drum, the second drum and the third drum.

[0018] The rotary kiln according to the embodiment of the present invention has at least the following beneficial effects: After the solid waste is dried and preheated in the first drum, it is sent into the second drum. The solid waste undergoes pyrolysis in the second drum. The pyrolysis liquid generated during the pyrolysis process flows out from the pyrolysis liquid outlet, while the solid waste part is discharged from the solid waste outlet, thereby separating the pyrolysis liquid and the solid waste. By discharging the pyrolysis liquid in advance, the situation of coking of the pyrolysis liquid in the high-temperature environment of the third drum after entering the third drum is avoided.

[0019] According to some embodiments of the present invention, the second drum is a drum made of high-temperature resistant porous ceramics.

[0020] According to some embodiments of the present invention, the second drum has a double-layer barrel wall structure, including an inner barrel wall and an outer barrel wall. The inner barrel wall is provided with pores, a pyrolysis oil export channel is formed between the inner barrel wall and the outer barrel wall, the pores are communicated with the pyrolysis oil export channel, and the pyrolysis liquid outlet is communicated with the pyrolysis oil export channel.

[0021] According to some embodiments of the present invention, the second drum is horizontally arranged, and the diameter of the second drum gradually increases from the solid waste outlet to the pyrolysis liquid outlet direction.

[0022] According to some embodiments of the present invention, it further includes a pyrolysis liquid recovery device. The pyrolysis liquid recovery device is provided with a recovery cavity, and the recovery cavity is hermetically sleeved on the second drum so that a sealed chamber is formed between the recovery cavity and the second drum, and the pyrolysis liquid outlet is located inside the sealed chamber.

[0023] According to some embodiments of the present invention, the pyrolysis liquid recovery device is provided with a nozzle for connecting to a blower.

[0024] According to some embodiments of the present invention, the first roller is horizontally arranged, and the first material transmission mechanism includes a first spiral blade, and the first spiral blade is arranged on the inner wall of the first roller;

[0025] The second roller is horizontally arranged, and the second material transmission mechanism includes a second spiral blade, and the second spiral blade is arranged on the inner wall of the second roller, and the spiral direction of the second spiral blade is opposite to that of the first spiral blade;

[0026] The third roller is horizontally arranged, and the third material transmission mechanism includes a third spiral blade, and the third spiral blade is arranged on the inner wall of the third roller, and the spiral direction of the third spiral blade is the same as that of the first spiral blade;

[0027] It further includes a driving device, and the driving device drives the first roller, the second roller and the third roller to rotate coaxially and in the same direction.

[0028] A solid waste treatment system according to an embodiment of the second aspect of the present invention includes the rotary kiln of the above embodiment.

[0029] The solid waste treatment system according to the embodiment of the present invention has at least the following beneficial effects: The solid waste treatment system adopting the above rotary kiln can reduce the energy consumption of the solid waste treatment system.

[0030] A solid waste treatment method according to an embodiment of the third aspect of the present invention includes the rotary kiln of the above embodiment, and the solid waste treatment is carried out through the following steps:

[0031] S100: Drying and preheating, putting the solid waste into the first roller from the first feed port, and the solid waste entering the first roller is discharged from the first discharge port under the action of the first material transmission mechanism. At the same time, the heating system regulates the temperature in the first roller to dry and preheat the solid waste in the first roller;

[0032] S200: Thermal decomposition, the second material transmission mechanism discharges the solid waste entering the second roller from the solid waste outlet. At the same time, the heating system regulates the temperature in the second roller to the thermal decomposition temperature, generally 200 - 500 °C, to carry out thermal decomposition on the solid waste in the second roller, and the pyrolysis liquid decomposed out flows out from the pyrolysis liquid outlet;

[0033] S300: Drying shrinkage and carbonization, the third material transmission mechanism discharges the solid waste entering the third roller from the second discharge port. At the same time, the heating system regulates the temperature in the third roller to the shrinkage and carbonization temperature, generally 500 - 950 °C, to carry out drying shrinkage and carbonization on the solid waste in the third roller.

[0034] The solid waste treatment method according to the embodiments of the present invention has at least the following beneficial effects: during the solid waste treatment process, by separating the pyrolysis liquid and the solid waste in the pyrolysis stage and discharging the pyrolysis liquid in advance, the situation of coking of the pyrolysis liquid in the high-temperature environment of the third drum is avoided, thus preventing problems such as reduced heat transfer efficiency and uneven heating of the rotary kiln.

[0035] According to some embodiments of the present invention, in step S200, it further includes the collection of the pyrolysis liquid. The fan is connected to the air nozzle on the pyrolysis liquid recovery device, and a negative pressure environment is formed in the closed chamber through the fan to suck out the pyrolysis liquid in the pores.

[0036] According to some embodiments of the present invention, in step S200, it further includes pore dredging. A positive pressure environment is formed in the closed chamber through the fan to blow out the pyrolysis liquid remaining in the pores in the reverse direction.

[0037] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The following further describes the present invention in conjunction with the drawings and embodiments, where:

[0039] Figure 1 It is a schematic structural diagram of a rotary kiln according to an embodiment of the present invention.

[0040] Reference Numerals in the Drawings:

[0041] The first drum 100; the first feed inlet 110; the first discharge outlet 120;

[0042] The first material transmission mechanism 210; the second material transmission mechanism 220; the third material transmission mechanism 230;

[0043] The second drum 300; the pyrolysis liquid outlet 310; the solid waste outlet 320;

[0044] The pyrolysis liquid recovery device 400; the closed chamber 410;

[0045] The third drum 500; the second discharge outlet 510;

[0046] The heating system 600; the first heating device 610; the second heating device 620;

[0047] The kiln tail hood 700; the pyrolysis gas outlet 710; the pyrolysis carbon outlet 720. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as limiting the present invention.

[0049] In the description of the present invention, it should be understood that with regard to the orientation description, such as up, down, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

[0050] In the description of the present invention, "a plurality of" means more than two. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or the sequence relationship of the indicated technical features.

[0051] In the description of the present invention, unless otherwise clearly defined, terms such as "set", "installed", "connected", etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0052] Refer to Figure 1 As shown, the present invention discloses a rotary kiln, comprising:

[0053] A first drum 100, provided with a first feed port 110 and a first discharge port 120;

[0054] A first material transmission mechanism 210, arranged inside the first drum 100, for discharging the solid waste entering from the first feed port 110 through the first discharge port 120;

[0055] A second drum 300, the second drum 300 is sleeved on the first drum 100, and the first discharge port 120 is located inside the second drum 300. The second drum 300 is provided with a pyrolysis liquid outlet 310 and a solid waste outlet 320, and the pyrolysis liquid of the second drum 300 can flow out through the pyrolysis liquid outlet 310;

[0056] A second material transmission mechanism 220, arranged inside the second drum 300, for discharging the solid waste entering the second drum 300 through the solid waste outlet 320;

[0057] A third drum 500, the third drum 500 is sleeved on the second drum 300, and the solid waste outlet 320 is located inside the third drum 500. The third drum 500 is provided with a second discharge port 510;

[0058] The third material transfer mechanism 230 is disposed inside the third drum 500 and is used to discharge the solid waste entering the third drum 500 from the second discharge port 510;

[0059] The heating system 600 is used to regulate the temperatures inside the first drum 100, the second drum 300, and the third drum 500.

[0060] In this embodiment, the solid waste is fed into the first drum 100 from the first feed port 110. Under the action of the first material transfer mechanism 210, the solid waste entering the first drum 100 is discharged from the first discharge port 120. At the same time, the heating system 600 regulates the temperature inside the first drum 100 to dry and preheat the solid waste in the first drum 100. Among them, the preheating temperature is about 200 °C. After preset drying, the moisture in the solid waste is removed, so that the solid waste entering the second drum 300 is preheated and dehydrated.

[0061] After being dried and preheated in the first drum 100, the solid waste is sent into the second drum 300. The solid waste undergoes pyrolysis in the second drum 300. The pyrolysis liquid generated during the pyrolysis process flows out from the pyrolysis liquid outlet 310, while the solid waste part is discharged from the solid waste outlet 320, thereby separating the pyrolysis liquid and the solid waste. By discharging the pyrolysis liquid in advance, the situation where the pyrolysis liquid cokes in the high-temperature environment of the third drum 500 after entering the third drum 500 with the solid waste is avoided.

[0062] The solid waste after separating the pyrolysis liquid is discharged from the solid waste outlet 320 through the second material transfer mechanism 220 and enters the third drum 500. The third material transfer mechanism 230 discharges the solid waste entering the third drum 500 from the second discharge port 510. During the transmission of the solid waste in the third drum 500, the heating system 600 regulates the temperature inside the third drum 500 to 500 - 950 °C to dry, shrink, and carbonize the solid waste in the third drum 500. The solid waste discharged from the second discharge port 510 has completed the drying, shrinking, and carbonization of the solid waste.

[0063] In this embodiment, the heating system 600 includes a first heating device 610 and a second heating device 620. The temperature inside the kiln is regulated through the cooperation of the first heating device 610 and the second heating device 620. At the same time, by coordinating the feeding speeds inside the first drum 100, the second drum 300, and the third drum 500, the temperatures of the materials inside the first drum 100, the second drum 300, and the third drum 500 are controlled.

[0064] Specifically, when the temperature of the material in the drum is lower than the required reaction temperature, the feeding speed in the corresponding drum is reduced, so as to increase the heating time of the material in the corresponding drum, and then the temperature of the material in the corresponding drum can be raised. When the temperature of the material in the drum is higher than the required reaction temperature, the feeding speed in the corresponding drum is increased, so as to shorten the heating time of the material in the corresponding drum, and then the temperature of the material in the corresponding drum can be reduced.

[0065] Reference Figure 1 As shown, the second drum 300 is horizontally arranged. The second drum 300 is a drum made of high-temperature resistant porous ceramics. There are pores on the wall of the second drum 300. The pyrolysis liquid outlet 310 communicates with the inside of the second drum 300 through the pores.

[0066] In this embodiment, the second drum 300 is a drum 300 made of high-temperature resistant porous ceramics. There are pores on the wall of the second drum 300. The second drum 300 made of high-temperature resistant porous ceramics can maintain its own characteristics unchanged under the high-temperature conditions of pyrolysis. The second drum 300 itself has pores. The pyrolysis liquid generated during the pyrolysis process will flow out of the second drum 300 through the pores and be recovered by the pyrolysis liquid recovery device 400. And the solid waste in the second drum 300 is retained in the second drum 300. Thus, the separation of pyrolysis liquid and solid waste is realized. Generally, the outlet of the pores is the pyrolysis liquid outlet 310.

[0067] In some embodiments, the second drum 300 has a double-layer wall structure, including an inner wall and an outer wall. There are pores on the inner wall. A pyrolysis oil export channel is formed between the inner wall and the outer wall. The pores communicate with the pyrolysis oil export channel, and the pyrolysis liquid outlet communicates with the pyrolysis oil export channel.

[0068] The pyrolysis liquid generated during the pyrolysis process will flow from the second drum 300 into the pyrolysis oil export channel through the pores, and then flow out from the pyrolysis liquid outlet and be recovered by the pyrolysis liquid recovery device 400. And the solid waste in the second drum 300 is retained in the second drum 300. Thus, the separation of pyrolysis liquid and solid waste is realized.

[0069] Reference Figure 1 As shown, the diameter of the second drum 300 gradually increases from the solid waste outlet 320 to the pyrolysis liquid outlet 310.

[0070] In this embodiment, the diameter of the second drum 300 gradually increases from the solid waste outlet 320 to the pyrolysis liquid outlet 310. As Figure 1As shown, the solid waste outlet 320 of the second drum 300 is on the left side, and the pyrolysis liquid outlet 310 is on the right side. The inner wall of the second drum 300 is in an inclined state with the left side higher than the right side. The pyrolysis liquid in the second drum 300 and the pyrolysis liquid in the pores of the second drum 300 will flow to the right under the action of gravity, that is, flow to the pyrolysis liquid outlet 310, which is conducive to the outward flow of the pyrolysis liquid.

[0071] It should be noted that the pores on the wall of the second drum 300 are preferably arranged in the part outside the third drum 500. The pyrolysis liquid in the second drum 300 flows into the third drum 500 through the pores. Because the inner wall of the second drum 300 is in an inclined state, even if the whole of the second drum 300 is provided with pores, it is also possible. The pyrolysis liquid in the second drum 300 and the pyrolysis liquid in the pores of the second drum 300 will flow to the right under the action of gravity, and only a small part of the pyrolysis liquid will enter the third drum 500, which will not have too much impact on the overall equipment.

[0072] Reference Figure 1 As shown, it further includes a pyrolysis liquid recovery device 400. The pyrolysis liquid recovery device 400 is provided with a recovery cavity, and the recovery cavity is hermetically sleeved on the second drum 300 so as to form a sealed chamber 410 between the recovery cavity and the second drum 300, and the pyrolysis liquid outlet 310 is located in the sealed chamber 410.

[0073] In this embodiment, by setting the pyrolysis liquid recovery device 400, the pyrolysis liquid discharged from the pyrolysis liquid outlet 310 of the second drum 300 is collected. Specifically, by hermetically sleeving the recovery cavity on the second drum 300, a sealed chamber 410 is formed between the recovery cavity and the second drum 300 to ensure that no external air enters the second drum 300 during the pyrolysis reaction. The pyrolysis liquid flowing out from the pyrolysis liquid outlet 310 then enters the sealed chamber 410. In addition, an oil discharge port can be provided on the pyrolysis liquid recovery device 400. After the pyrolysis liquid in the recovery cavity is collected to a certain amount, the pyrolysis liquid is discharged.

[0074] Since in this embodiment, the pyrolysis liquid of the second drum 300 is discharged through the pores on the second drum 300, in order to prevent solid waste from being discharged through the pores, the aperture of the pores is relatively small. Therefore, the fluidity of the pyrolysis liquid in the pores is low and the discharge speed is slow. It is easy to have a situation where part of the pyrolysis liquid stays in the pores and causes the pores to be blocked.

[0075] Based on this, a nozzle for connecting to a blower is provided in the pyrolysis liquid recovery device 400. During the pyrolysis process, the blower is connected to the nozzle, so that a negative pressure environment is formed in the sealed chamber 410. Under the action of the negative pressure, the pyrolysis liquid can be discharged from the pores. To prevent the pores from being blocked, a positive pressure environment is formed in the sealed chamber 410 by the blower. Under the action of the positive pressure, the pyrolysis liquid in the pores can be blown back into the second drum 300 in the reverse direction. It is possible to avoid the pyrolysis liquid staying in the pores from blocking the pores.

[0076] In some embodiments, referring to Figure 1 as shown, the first drum 100 is horizontally arranged, and the first material transmission mechanism 210 includes a first spiral blade, and the first spiral blade is arranged on the inner wall of the first drum 100;

[0077] The second drum 300 is horizontally arranged, and the second material transmission mechanism 220 includes a second spiral blade, and the second spiral blade is arranged on the inner wall of the second drum 300, and the spiral direction of the second spiral blade is opposite to that of the first spiral blade;

[0078] The third drum 500 is horizontally arranged, and the third material transmission mechanism 230 includes a third spiral blade, and the third spiral blade is arranged on the inner wall of the third drum 500, and the spiral direction of the third spiral blade is the same as that of the first spiral blade;

[0079] It further includes a driving device, and the driving device drives the first drum 100, the second drum 300 and the third drum 500 to rotate coaxially and in the same direction.

[0080] In this embodiment, the first drum 100, the second drum 300 and the third drum 500 are relatively fixedly installed together. Since the spiral direction of the second spiral blade is opposite to that of the first spiral blade and the third spiral blade, the advancing direction of the material in the second drum 300 is opposite to the advancing direction of the material in the first drum 100 and the third drum 500. This greatly simplifies the overall structure of the rotary kiln.

[0081] In some embodiments, referring to Figure 1 as shown, the first drum 100 is horizontally arranged, and the first material transmission mechanism 210 includes a first spiral blade and a first driving unit, the first spiral blade is arranged on the inner wall of the first drum 100, and the first driving unit drives the first drum 100 to rotate around its own axis.

[0082] In this embodiment, the first drum 100 rotates about its axis under the action of the first driving unit. During the rotation of the first drum 100, the first spiral blade in the first drum 100 will push the solid waste in the drum forward, so as to discharge the solid waste entering the first drum 100 from the first discharge port. By controlling the rotation speed of the first drum 100, the feeding speed can be controlled, and further the temperature of the material in the first drum 100 can be controlled.

[0083] In other embodiments, a spiral feeding shaft may also be provided in the first drum 100, and by driving the spiral feeding shaft to rotate, the material in the first drum 100 is pushed forward.

[0084] The second drum 300 is horizontally arranged. The second material transmission mechanism 220 includes a second spiral blade and a second driving unit. The second spiral blade is arranged on the inner wall of the second drum 300, and the second driving unit drives the second drum 300 to rotate about its own axis;

[0085] In this embodiment, the second drum 300 rotates about its axis under the action of the second driving unit. During the rotation of the second drum 300, the second spiral blade in the second drum 300 will push the solid waste in the drum forward, so as to discharge the solid waste entering the second drum 300 from the second discharge port 510. By controlling the rotation speed of the second drum 300, the feeding speed can be controlled, and further the temperature of the material in the second drum 300 can be controlled.

[0086] The third drum 500 is horizontally arranged. The third material transmission mechanism 230 includes a third spiral blade and a third driving unit. The third spiral blade is arranged on the inner wall of the third drum 500, and the third driving unit drives the third drum 500 to rotate about its own axis.

[0087] In this embodiment, the third drum 500 rotates about its axis under the action of the third driving unit. During the rotation of the third drum 500, the third spiral blade in the third drum 500 will push the solid waste in the drum forward, so as to discharge the solid waste entering the third drum 500 from the solid waste outlet 320. By controlling the rotation speed of the third drum 500, the feeding speed can be controlled, and further the temperature of the material in the third drum 500 can be controlled.

[0088] It further includes a kiln tail hood 700. The kiln tail hood 700 is arranged at the outlet end of the third drum 500. The solids discharged from the third drum 500 are discharged from the pyrolysis carbon outlet 720 at the lower part, and the pyrolysis gas is discharged from the pyrolysis gas outlet 710 at the upper part.

[0089] The present invention also discloses a solid waste treatment system, including the rotary kiln of the above embodiment.

[0090] Since the solid waste treatment system adopts all the technical solutions of the rotary kiln in the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here.

[0091] The present invention also discloses a solid waste treatment method, the rotary kiln in the above embodiments, and the solid waste treatment is carried out through the following steps:

[0092] S100: Drying and preheating. The solid waste is fed into the first drum 100 from the first feed port 110. Under the action of the first material transmission mechanism 210, the solid waste entering the first drum 100 is discharged from the first discharge port 120. At the same time, the heating system 600 regulates the temperature in the first drum 100 to dry and preheat the solid waste in the first drum 100.

[0093] S200: Thermal decomposition. The second material transmission mechanism 220 discharges the solid waste entering the second drum 300 from the solid waste outlet 320. At the same time, the heating system 600 regulates the temperature in the second drum 300 to 200 - 500 °C to thermally decompose the solid waste in the second drum 300, and the pyrolysis liquid thermally decomposed flows out from the pyrolysis liquid outlet 310.

[0094] S300: Drying shrinkage and carbonization. The third material transmission mechanism discharges the solid waste entering the third drum 500 from the second discharge port 510. At the same time, the heating system 600 regulates the temperature in the third drum 500 to 500 - 950 °C to carry out drying shrinkage and carbonization on the solid waste in the third drum 500.

[0095] During the solid waste treatment process, by separating the pyrolysis liquid and the solid waste in the thermal decomposition stage and discharging the pyrolysis liquid in advance, it is possible to avoid the situation of coking when the pyrolysis liquid enters the third drum 500 in the high-temperature environment of the third drum 500, resulting in problems such as reduced heat transfer efficiency and uneven heating of the rotary kiln.

[0096] In some embodiments of the present invention, in step S200, it further includes the collection of pyrolysis liquid. The fan is connected to the air nozzle on the pyrolysis liquid recovery device 400, and a negative pressure environment is formed in the closed chamber 410 through the fan to suck out the pyrolysis liquid in the pores.

[0097] During the thermal decomposition process, by connecting the fan and the air nozzle, a negative pressure environment is formed in the closed chamber 410, and under the action of the negative pressure, the pyrolysis liquid can be discharged from the pores.

[0098] In some embodiments of the present invention, in step S200, it further includes pore dredging. A positive pressure environment is formed in the closed chamber 410 through the fan to blow out the pyrolysis liquid remaining in the pores in the reverse direction.

[0099] To prevent the pores from being blocked, a positive pressure environment is formed in the sealed chamber 410 by a blower. Under the action of the positive pressure, the pyrolysis liquid in the pores can be blown back into the second drum 300 in the reverse direction, which can avoid the pyrolysis liquid remaining in the pores from blocking the pores.

[0100] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention within the scope of knowledge possessed by those of ordinary skill in the art to which the present invention pertains.

Claims

1. A rotary kiln, characterized in that, Comprising: A first drum, provided with a first feed inlet and a first discharge outlet; A first material transmission mechanism, arranged inside the first drum, for discharging the solid waste entering from the first feed inlet from the first discharge outlet; A second drum, the second drum being sleeved on the first drum, and the first discharge outlet being located inside the second drum. The second drum is provided with a pyrolysis liquid outlet and a solid waste outlet, and the pyrolysis liquid of the second drum can flow out from the pyrolysis liquid outlet; A second material transmission mechanism, arranged inside the second drum, for discharging the solid waste entering the second drum from the solid waste outlet; A third drum, the third drum being sleeved on the second drum, and the solid waste outlet being located inside the third drum. The third drum is provided with a second discharge outlet; A third material transmission mechanism, arranged inside the third drum, for discharging the solid waste entering the third drum from the second discharge outlet; A heating system, for regulating the temperatures inside the first drum, the second drum and the third drum; Wherein, the diameter of the second drum gradually increases from the solid waste outlet to the pyrolysis liquid outlet direction.

2. The rotary kiln according to claim 1, characterized in that: The second drum is a drum made of high-temperature resistant porous ceramics.

3. The rotary kiln according to claim 1, characterized in that: The second drum has a double-layer barrel wall structure, including an inner barrel wall and an outer barrel wall. The inner barrel wall is provided with pores, a pyrolysis oil export channel is formed between the inner barrel wall and the outer barrel wall, the pores are communicated with the pyrolysis oil export channel, and the pyrolysis liquid outlet is communicated with the pyrolysis oil export channel.

4. The rotary kiln according to claim 2 or 3, characterized in that: It further includes a pyrolysis liquid recovery device. The pyrolysis liquid recovery device is provided with a recovery cavity. The recovery cavity is hermetically sleeved on the second drum, so as to form a sealed chamber between the recovery cavity and the second drum, and the pyrolysis liquid outlet is located inside the sealed chamber.

5. The rotary kiln according to claim 1, characterized in that: The first drum is horizontally arranged. The first material transmission mechanism includes a first spiral blade, and the first spiral blade is arranged on the inner wall of the first drum; The second drum is horizontally arranged. The second material transmission mechanism includes a second spiral blade, and the second spiral blade is arranged on the inner wall of the second drum. The spiral direction of the second spiral blade is opposite to that of the first spiral blade; The third drum is horizontally arranged. The third material transmission mechanism includes a third spiral blade, and the third spiral blade is arranged on the inner wall of the third drum. The spiral direction of the third spiral blade is the same as that of the first spiral blade; It further includes a driving device, and the driving device drives the first drum, the second drum and the third drum to rotate coaxially and in the same direction.

6. A solid waste treatment system, characterized in that: Comprising the rotary kiln according to any one of claims 1 to 5.

7. A solid waste treatment method, characterized in that, Comprising the rotary kiln according to any one of claims 1 to 5, and the solid waste treatment is carried out through the following steps: S100: Drying and preheating. The solid waste is fed into the first drum from the first feed inlet. The solid waste entering the first drum is discharged from the first discharge outlet under the action of the first material transmission mechanism. Meanwhile, the heating system regulates the temperature inside the first drum to dry and preheat the solid waste in the first drum; S200: Thermal decomposition. The second material transfer mechanism discharges the solid waste entering the second drum from the solid waste outlet. Meanwhile, the heating system adjusts the temperature inside the second drum to the thermal decomposition temperature to perform thermal decomposition on the solid waste in the second drum, and the pyrolysis liquid produced by the thermal decomposition flows out from the pyrolysis liquid outlet. S300: Drying shrinkage and carbonization. The third material transfer mechanism discharges the solid waste entering the third drum from the second discharge port. Meanwhile, the heating system adjusts the temperature inside the third drum to the drying shrinkage and carbonization temperature to perform drying shrinkage and carbonization on the solid waste in the third drum.

8. The solid waste treatment method according to claim 7, characterized in that: In step S200, it also includes the collection of pyrolysis liquid. The fan is connected to the air nozzle on the pyrolysis liquid recovery device, and a negative pressure environment is formed in the closed chamber through the fan to suck out the pyrolysis liquid in the pores.

9. The solid waste treatment method according to claim 8, characterized in that: In step S200, it also includes pore dredging. A positive pressure environment is formed in the closed chamber through the fan to blow out the pyrolysis liquid remaining in the pores in the reverse direction.

Images