A system and method for co-processing organic hazardous waste by temperature-controlled and oxygen-controlled combustion

Abstract

A system for the coordinated disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, comprising a rotary kiln; the rotary kiln comprising a kiln head, a kiln body, and a kiln tail; a material inlet being provided at the kiln head; a kiln body comprising a furnace lining and a furnace; a material outlet and a kiln tail air duct being provided at the kiln tail; the furnace being divided into a pyrolysis chamber and an incineration chamber along the direction of the material; a kiln air duct being provided within the furnace lining corresponding to the pyrolysis chamber; one end of the kiln air duct extending into the kiln head and the other end communicating with the incineration chamber; an annular air duct being provided at the kiln head; the kiln air duct being communicated with a primary air duct disposed outside the rotary kiln via the annular air duct; a secondary air duct branching from the primary air duct; the secondary air duct passing through the kiln head and communicating with the pyrolysis chamber. The present invention proposes a dual-purpose rotary kiln for both forward and reverse flow, employing different combustion modes for different raw materials, thereby expanding the adaptability of the rotary kiln to different materials.

Description

Technical Field

[0001] The present invention relates to a process for the disposal of organic hazardous waste, and in particular to a system and method for the coordinated disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, belonging to the technical field of coordinated sintering treatment of organic hazardous waste. Background Art

[0002] Generally, rotary incinerators are used to incinerate organic hazardous waste and are a key component of hazardous waste incineration systems. Since organic hazardous waste contains organic matter and possesses a certain calorific value, incineration is suitable for its disposal. This not only reduces the volume of hazardous waste but also recovers heat energy from the waste, achieving comprehensive resource utilization.

[0003] Existing rotary kilns for hazardous waste incineration are primarily used to incinerate municipal hazardous waste, including organic resins and municipal sludge. However, with increasing demand from steel companies to ensure that no solid waste leaves the factory, some steel mills have begun constructing on-site hazardous waste incineration facilities to incinerate their own hazardous waste. However, hazardous waste generated by steel mills has a high iron content, making it prone to slagging and agglomeration. Furthermore, existing rotary kilns for municipal hazardous waste incineration also suffer from uneven temperature distribution, resulting in relatively low incineration efficiency.

[0004] In the existing technology, rotary kilns are mostly used to dispose of municipal organic hazardous waste with low iron content. The hazardous waste incineration and flue gas purification process usually adopts "rotary kiln + secondary combustion chamber + waste heat boiler (SNCR denitrification) + flue gas quenching + dry deacidification (slaked lime and activated carbon injection) + bag filter + induced draft fan + pre-wash tower + wet scrubber + flue gas reheater + chimney". The main purpose of this process is to fully burn the organic matter in the hazardous waste. The incineration equipment used is a rotary kiln, such as Figure 1 As shown in the figure, zone I is the kiln head feeding area, zone II is the incineration area, the kiln head feeding area is equipped with a hazardous waste feeding port and an air inlet, and the kiln tail is equipped with a material outlet. In actual application, the rotary kiln has an inclination angle of about 5° ( Figure 1 The material and air enter the rotary kiln from the kiln head (Zone I) together. Driven by the kiln's rotation and inclination, the material moves toward the kiln tail, where it mixes with the air and burns. The final residue is discharged from the rotary kiln through the material outlet. Currently, the residue on the market falls directly into a pool for wet cooling after leaving the rotary kiln. The cooled residue is then removed, solidified, and landfilled.

[0005] The primary incineration temperature for hazardous waste in a rotary kiln is approximately 850-950°C, with a residence time of 30-40 minutes. Under these conditions, the organic matter in the hazardous waste is fully burned. According to current standards and environmental impact assessment requirements, the ignition reduction rate of the incineration residue must be below 5%.

[0006] Existing hazardous waste incineration technology primarily targets municipal organic hazardous waste. However, when treating organic hazardous waste from steel mills, the iron content is relatively high, such as steel mill sludge, which can reach 50% to 60%. If existing technology is still used to incinerate iron-containing sludge, the iron element forms a low-temperature eutectic with the metal oxides in the ash. At incineration temperatures of 850-950°C, this easily forms slagging and rings in the rotary kiln. The iron-containing residue forms large, highly sturdy agglomerates in the rotary kiln, causing blockage and disrupting normal production.

[0007] In the existing technology, all organic matter is fully incinerated in the rotary kiln to release heat. Although the rotary kiln hazardous waste incineration disposal line is equipped with a waste heat boiler to recover the waste heat, the rotary kiln itself dissipates a lot of heat, and the utilization rate of the heat in the organic matter is low.

[0008] In existing technologies, municipal hazardous waste incineration residues and fly ash, due to their high levels of heavy metals and certain dioxin pollutants, are typically simply stabilized using cement, lime, and water before being landfilled. This wasteful disposal process is particularly wasteful of residual resources, particularly steel mill hazardous waste, which contains high iron content and high recycling value. However, this iron resource is not effectively reused. Furthermore, landfilling does not completely eliminate its environmental impact and still poses the risk of secondary pollution. Summary of the Invention

[0009] To address the aforementioned issues in the prior art, the present invention proposes a system for the coordinated treatment of organic hazardous waste using temperature- and oxygen-controlled combustion. The system includes a rotary kiln capable of both downstream and countercurrent operation for different types of hazardous organic waste. When the material to be treated is high-volatile organic hazardous waste, the kiln can function as a two-stage countercurrent kiln for pyrolysis and incineration. When the material to be treated is low-volatile organic hazardous waste, the kiln can be converted directly to a downstream rotary kiln without any modifications, thereby expanding the rotary kiln's adaptability to different materials. The system also includes a sintering machine. The present invention distributes the incineration residue from the incineration of hazardous waste in the rotary kiln to the sintering machine for disposal. Residual organic matter in the incineration residue can be graded and utilized during sintering.

[0010] Correspondingly, the present invention also proposes a method for the coordinated disposal of organic hazardous wastes based on temperature-controlled and oxygen-controlled combustion in a rotary kiln-sintering machine. Compared with the prior art, the present invention controls the incineration temperature in the rotary kiln so that the hazardous waste is incinerated below the low-temperature eutectic point, effectively alleviating the ringing and slagging phenomenon when the rotary kiln incinerates iron-containing organic solid waste. The incineration residue of the rotary kiln is co-disposed of using the sintering process of the steel enterprise, which can effectively recover the iron element in the iron-containing solid waste, and the heavy metals in the residue are disposed of by the sintering process, completely eliminating the environmental impact of the solid waste and the risk of secondary pollution. Moreover, the temperature-controlled and oxygen-controlled incineration in the rotary kiln also allows the organic matter in the hazardous waste to be partially preserved, which is fully utilized in the sintering process, thereby improving the utilization rate of thermal energy.

[0011] According to a first embodiment of the present invention, a system for co-processing organic hazardous wastes by temperature-controlled and oxygen-controlled combustion is provided.

[0012] A system for the coordinated disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, the system comprising a rotary kiln. The rotary kiln comprises a kiln head, a kiln body and a kiln tail. A material inlet is provided at the kiln head. The kiln body comprises a furnace lining and a furnace. A material outlet and a kiln tail air duct are provided at the kiln tail. Along the direction of the material, the furnace is divided into a pyrolysis chamber and an incineration chamber. An in-kiln air duct is provided inside the furnace lining corresponding to the pyrolysis chamber. One end of the in-kiln air duct extends into the kiln head, and the other end is connected to the incineration chamber. An annular air duct is also provided on the kiln head. The in-kiln air duct is connected to a primary air duct arranged outside the rotary kiln through the annular air duct. A secondary air duct is branched from the primary air duct. The secondary air duct passes through the kiln head and is connected to the pyrolysis chamber.

[0013] In the present invention, the system also includes a sintering machine located downstream of the rotary kiln. A lower-level material distributor, a middle-level material distributor, and an upper-level material distributor are sequentially positioned above the sintering trolley in the sintering machine's feed section, along the material flow path. The material outlet of the rotary kiln is connected to the lower-level material distributor, the middle-level material distributor, or the upper-level material distributor.

[0014] In the present invention, the system further includes a hot slag cooler disposed between the rotary kiln and the sintering machine. The hot slag cooler is provided with a hot slag inlet, a cold slag outlet, a cold medium inlet, and a hot medium outlet. The rotary kiln's material outlet is connected to the hot slag inlet of the hot slag cooler. The cold slag outlet of the hot slag cooler is connected to a lower, middle, or upper material distributor on the sintering machine. Preferably, the hot slag cooler is a dry-type hot slag cooler, preferably a partition-type heat exchanger.

[0015] Preferably, the rotary kiln is provided with n kiln air ducts. The n kiln air ducts are evenly distributed along the circumference of the rotary kiln. Each kiln air duct is connected to an annular air duct provided at the kiln head. Here, n is 2-30, preferably 3-20.

[0016] Preferably, a three-way valve is provided at the location where the primary air duct branches off into the secondary air duct. An air extraction device is provided on the secondary air duct. Preferably, a supplementary heat burner is further provided at the kiln tail of the rotary kiln.

[0017] Preferably, a temperature detection device is provided in the combustion chamber of the rotary kiln, a material iron content detection device is provided at the material inlet at the kiln head, and a gas analyzer is provided on the primary air duct near the annular air duct.

[0018] According to a second embodiment of the present invention, a method for co-disposal of organic hazardous wastes by temperature-controlled and oxygen-controlled combustion is provided.

[0019] A method for co-processing organic hazardous waste by temperature-controlled and oxygen-controlled combustion or a method using the system described in the first embodiment, the method comprising the following steps:

[0020] 1) Pyrolysis: Highly volatile organic waste is transported to the rotary kiln through the material inlet at the kiln head. Combustion air enters the rotary kiln through the kiln tail air duct. The high-volatile organic waste first enters the rotary kiln's pyrolysis chamber for drying and pyrolysis. After pyrolysis, the residue and pyrolysis gases enter the incineration chamber.

[0021] 2) Incineration: Material residue, pyrolysis gases, and combustion air are mixed and burned in the incineration chamber. After incineration, the hot slag is discharged from the rotary kiln through the material outlet at the kiln tail. The incinerated flue gas is discharged from the rotary kiln through the kiln air duct, the annular air duct, and the primary air duct.

[0022] 3) Flue gas circulation: Part of the flue gas that enters the primary air duct in step 2) enters the rotary kiln again through the secondary air duct and completes the pyrolysis and incineration process together with the materials in the rotary kiln.

[0023] Preferably, the high-volatile organic hazardous waste is an organic hazardous waste having a mass percentage of volatile matter on a dry basis greater than or equal to H%, wherein H is 6-12, preferably 7-10.

[0024] In the present invention, the method further comprises:

[0025] 4) Cooling: The hot slag discharged from the rotary kiln in step 2) is transported to a hot slag cooler, into which a cooling medium is introduced. The hot slag and the cooling medium exchange heat within the hot slag cooler, resulting in cold slag and a hot medium.

[0026] 5) Sintering: Place the cold slag obtained in step 4) and the sintering raw materials on a sintering trolley and ignite and sinter.

[0027] Preferably, in step 4), the cooling medium introduced into the hot slag cooler is cold air. The cold air is converted into hot air after heat exchange in the hot slag cooler and then discharged from the hot medium outlet. The hot air is then transported to the kiln tail air duct of the rotary kiln as combustion air.

[0028] Preferably, in step 4), the cooling medium introduced into the hot slag cooler is cooling water. The cooling water is converted into hot water through heat exchange in the hot slag cooler and then discharged from the heat medium outlet, and the hot water is used as boiler feed water.

[0029] In the present invention, in step 2), the iron content w of the high-volatile organic hazardous waste entering the rotary kiln is detected by a material iron content detection device. The combustion temperature T0 required to be controlled in the incineration chamber is determined based on the detected material iron content. Specifically:

[0030] When w>50%, T0 is 550~650℃.

[0031] When 25%<w≤50%, T0 is 650~750℃.

[0032] When 5%≤w≤25%, T0 is 750~850℃.

[0033] When w<5%, T0 is 850~950℃.

[0034] In the present invention, in step 1), the pyrolysis temperature in the pyrolysis chamber of the rotary kiln is 200-550°C, preferably 300-500°C.

[0035] In the present invention, the type of cold slag obtained in step 4) is determined based on the combustion temperature T0 that needs to be controlled in the incineration chamber in step 2). Specifically:

[0036] When T0 is 550-650°C, the cold slag obtained in step 4) is a high-carbon residue.

[0037] When T0 is 650-850°C, the cold slag obtained in step 4) is a low-carbon residue.

[0038] When T0 is 850-950°C, the cold slag obtained in step 4) is a carbon-free residue.

[0039] Preferably, the organic matter content of the high carbon residue is greater than Z%, and the organic matter content of the low carbon residue is less than or equal to Z%, wherein Z is 4-12, preferably 5-10.

[0040] In the present invention, according to the type of cold slag obtained in step 4), step 5) is specifically as follows:

[0041] When the cold slag obtained in step 4) is high-carbon residue, the high-carbon residue is placed in the upper distribution machine on the sintering machine, that is, the sintering raw materials are distributed to the sintering trolley, and then the high-carbon residue is distributed above the sintering raw materials through the upper distribution machine, and ignited and sintered.

[0042] When the cold slag obtained in step 4) is low-carbon residue, the sintering mixture obtained by mixing the low-carbon residue with the sintering raw materials is placed in the middle-layer distribution machine on the sintering machine, and then the sintering mixture is distributed to the sintering trolley through the middle-layer distribution machine and ignited and sintered.

[0043] When the cold slag obtained in step 4) is a carbon-free residue, the carbon-free residue is placed in the lower distribution machine on the sintering machine, and the carbon-free residue is distributed as a base material to the sintering trolley through the lower distribution machine. Then, the sintering raw material is distributed above the base material and ignited for sintering.

[0044] In the present invention, in the incineration process of step 2), when the material residue, pyrolysis gas and combustion-supporting air are burned, the temperature changes in the incineration chamber are monitored in real time, and the oxygen content and combustible component content in the flue gas after incineration are monitored in real time, and then the air intake and / or feed amount and / or the heat supply of the heat supply burner in the rotary kiln are adjusted, thereby achieving the control of the process conditions of the incineration process and controlling the combustion temperature in the incineration chamber.

[0045] In the present invention, the process conditions of the incineration process are controlled to control the combustion temperature in the incineration chamber, which specifically includes the following sub-steps:

[0046] 201) As the material residue, pyrolysis gas, and combustion air burn, the temperature detection device monitors the combustion temperature within the incineration chamber in real time. During the real-time monitoring process, the detected real-time combustion temperature T within the incineration chamber is compared with the desired combustion temperature T0 within the incineration chamber.

[0047] 201a) If the real-time combustion temperature T in the incineration chamber is equal to the combustion temperature T0 to be controlled, the incineration process is running normally at this time, and the temperature detection device continues to monitor.

[0048] 201b) If the real-time combustion temperature T in the incineration chamber is less than the desired combustion temperature T0, the temperature in the incineration chamber needs to be increased. At this time, the real-time oxygen content and the real-time combustible component content in the flue gas after incineration are detected by a gas analyzer.

[0049] If the real-time oxygen content and combustible component content in the flue gas after incineration are detected to be normal, the supplementary heat burner is turned on, or the feed amount in the rotary kiln is increased, and the air intake in the rotary kiln is increased at the same time, so that T=T0.

[0050] If it is detected that the real-time oxygen content in the flue gas after incineration is low, the air flow into the rotary kiln is increased, and the feed amount into the rotary kiln is increased at the same time, or the supplementary heat burner is turned on to make T=T0.

[0051] If it is detected that the real-time oxygen content in the flue gas after incineration is too high and the real-time combustible component content is normal, the air flow into the rotary kiln is reduced, or the feed amount into the rotary kiln is increased, or the supplementary heat burner is turned on to make T=T0.

[0052] 201c) If the real-time combustion temperature T in the incineration chamber is greater than the desired combustion temperature T0, the temperature in the incineration chamber needs to be lowered. At this time, the real-time oxygen content and the real-time combustible component content in the flue gas after incineration are detected by a gas analyzer.

[0053] If the real-time oxygen content and combustible component content in the flue gas after incineration are detected to be normal, the heat supply of the heat supply burner is reduced, or the feed amount in the rotary kiln is reduced, and the air intake in the rotary kiln is reduced at the same time, so that T=T0.

[0054] If the real-time oxygen content in the flue gas after incineration is detected to be low, the air flow into the rotary kiln is increased, while the feed amount into the rotary kiln is reduced, or the heat supply of the heat supply burner is reduced, so that T=T0.

[0055] If it is detected that the real-time oxygen content in the flue gas after incineration is too high and the real-time combustible component content is normal, the air intake into the rotary kiln is reduced, the feed amount into the rotary kiln is reduced, or the heat supply of the heat supply burner is reduced to make T=T0.

[0056] According to a third embodiment of the present invention, a method for co-disposal of organic hazardous wastes by temperature-controlled and oxygen-controlled combustion is provided.

[0057] A method for co-processing organic hazardous waste by temperature-controlled and oxygen-controlled combustion or a method using the system of the first embodiment, the method comprising the following steps:

[0058] a) Low-volatile organic waste is transported to the rotary kiln through the material inlet at the kiln head. Combustion air enters the rotary kiln through the secondary air duct at the kiln head. The low-volatile organic waste and combustion air mix and burn in the furnace.

[0059] b) After the incineration is completed, the hot slag is discharged from the rotary kiln through the material outlet at the kiln tail. The smoke after incineration is discharged from the rotary kiln through the kiln tail air duct.

[0060] c) transporting the hot slag discharged from the rotary kiln in step b) to a hot slag cooler, and introducing a cooling medium into the hot slag cooler. The hot slag and the cooling medium exchange heat in the hot slag cooler, and after the heat exchange is completed, cold slag and hot medium are obtained.

[0061] d) placing the cold slag obtained in step c) and the sintering raw materials on a sintering trolley and igniting and sintering.

[0062] Preferably, the low-volatile organic hazardous waste is an organic hazardous waste having a dry-base volatile content of less than H%, wherein H is 6-12, preferably 7-10.

[0063] Preferably, in step a), the combustion-supporting air also enters the incineration chamber of the rotary kiln through the primary air duct, the annular air duct, and the kiln air duct.

[0064] Preferably, the amount of the combustion-supporting air entering the rotary kiln through the secondary air duct accounts for 20% to 45%, preferably 30% to 40%, of the total air volume required in the rotary kiln.

[0065] In the existing technology, hazardous waste incineration rotary kilns are mainly used to incinerate municipal hazardous waste, including organic resins, municipal sludge, etc. However, with the increasing requirements of steel companies to "keep solid waste out of the factory", some steel mills have begun to build hazardous waste incineration projects within the factory to incinerate the hazardous waste generated by the steel companies themselves. However, the hazardous waste generated by steel companies has a high iron content, which is prone to slagging and agglomeration, causing the rotary kiln to be blocked. At the same time, the existing municipal hazardous waste incineration rotary kilns also have uneven temperature distribution and relatively low incineration efficiency. Moreover, in the existing technology, all organic matter in hazardous waste is fully burned and released in the rotary kiln. Although the rotary kiln hazardous waste incineration disposal line is equipped with a waste heat boiler to recover the waste heat, the rotary kiln itself dissipates a lot of heat, so the utilization rate of the heat in the organic matter is low. Furthermore, municipal hazardous waste incineration residues and fly ash, due to their high levels of heavy metals and dioxin, are typically stabilized using cement, lime, and water before being landfilled. This wasteful disposal process is particularly wasteful of residual resources, particularly steel mill hazardous waste, which contains high iron content and high recycling value. However, this iron resource is not effectively reused. Furthermore, landfilling does not completely eliminate its environmental impact and still poses the risk of secondary pollution.

[0066] In response to the defects in the hazardous waste disposal process in the prior art, the present invention proposes a system for the coordinated disposal of organic hazardous wastes by temperature-controlled and oxygen-controlled combustion. The system includes a rotary kiln, which includes a kiln head, a kiln body, and a kiln tail. A material inlet is provided on the kiln head, the kiln body includes a furnace lining and a furnace, and a material outlet and a kiln tail air duct are provided on the kiln tail. Along the direction of the material, the furnace is divided into a pyrolysis chamber and an incineration chamber. An in-kiln air duct is provided inside the furnace lining corresponding to the pyrolysis chamber, one end of the in-kiln air duct extends into the kiln head, and the other end is connected to the incineration chamber. An annular air duct is also provided on the kiln head. The in-kiln air duct is connected to a primary air duct arranged outside the rotary kiln through the annular air duct. A secondary air duct is separated from the primary air duct, and the secondary air duct passes through the kiln head and is connected to the pyrolysis chamber. In the present invention, the rotary kiln can be used for both downstream and upstream treatment of different types of organic hazardous wastes.

[0067] When the material to be processed is a high-volatile organic hazardous waste (such as iron-containing oil sludge), the rotary kiln can be used as a two-stage countercurrent rotary kiln for pyrolysis and incineration. At this time, the kiln head, pyrolysis chamber, incineration chamber, and kiln tail correspond to the feeding section, material pyrolysis section, full incineration section, and discharge section. High-volatile organic hazardous waste is fed into the rotary kiln from the material inlet of the kiln head by a hydraulic push rod or other forms, and the combustion air enters the rotary kiln from the kiln tail air duct in the opposite direction (opposite to the direction of the material). The high-volatile organic hazardous waste entering the rotary kiln first enters the pyrolysis chamber for drying and pyrolysis. The pyrolysis chamber is an oxygen-deficient, high-temperature environment with a temperature of about 200 to 550°C (preferably 300 to 500°C). The heat source of the pyrolysis chamber is mainly the heat exchange in the furnace after the high-temperature flue gas generated by the incineration process enters the kiln air duct. High-volatile organic hazardous waste is dried and pyrolyzed in the pyrolysis chamber, and the volatile matter in the material is precipitated in the form of combustible gases such as CH4, H2, and CO. The airflow direction of the material pyrolysis section is from the kiln head to the kiln tail, that is, the material residue and pyrolysis gas after pyrolysis enter the full incineration section, and the material residue and pyrolysis gas are mixed with the combustion-supporting air entering the incineration chamber and burn violently. The hot slag after incineration is discharged from the rotary kiln through the material outlet at the kiln tail, and the flue gas after incineration is discharged from the rotary kiln through the kiln air duct, the annular air duct and the primary air duct, and in the process, the heat required for pyrolysis is provided to the pyrolysis chamber. The present invention is aimed at the pyrolysis-incineration two-stage countercurrent incineration rotary kiln where high-volatile organic hazardous waste is located, which improves the combustion efficiency and solves the problem that hazardous wastes such as oil sludge are prone to agglomeration, slagging and clogging of rotary kilns.

[0068] It should be noted that the present invention is provided with a secondary air duct at the kiln head position, and its main function is: the combustible pyrolysis gas pyrolyzed out of the pyrolysis chamber (from the kiln head to the kiln tail) is strongly mixed and burned with the mixed gas of air and flue gas from the incineration chamber (from the kiln tail to the kiln head). However, some combustible gas may still not be completely burned and directly brought into the air duct in the kiln, causing the flue gas to contain a large amount of combustible matter. In this way, when the flue gas passes through the three-way valve at the connection position of the primary air duct and the secondary air duct, part of the flue gas is sucked into the secondary air duct by the exhaust device (such as an exhaust pump) and returns to the rotary kiln for re-reaction. Another function of circulating flue gas is that the volume of pyrolysis gas produced by the pyrolysis of materials in the pyrolysis chamber is much smaller than the flue gas and air mixture produced by the combustion of materials in the incineration chamber. Therefore, when the pyrolysis gas is mixed with the flue gas and air mixture, the pyrolysis gas velocity is too low, making it difficult to achieve a good mixing and combustion effect. However, mixing the circulating flue gas with the pyrolysis gas can increase the volume of the pyrolysis gas and increase the kinetic energy of the pyrolysis gas moving toward the kiln tail, thereby enhancing the gas mixing effect in the kiln and accelerating the combustion reaction. At the same time, the circulating flue gas can also provide some heat for the pyrolysis of materials.

[0069] When the material to be processed is low-volatile organic hazardous waste (such as converter mud), the rotary kiln can be directly converted into a downstream rotary kiln without any changes. Since the volatility of low-volatile organic hazardous waste itself is not high, even after pyrolysis, it will not produce much volatiles. Therefore, it is not very meaningful to first pass the material pyrolysis section. At this time, the kiln head, pyrolysis chamber, incineration chamber, and kiln tail correspond to the feeding section, primary incineration section, secondary incineration section, and discharge section, of which the secondary incineration section is the main combustion zone. Low-volatile organic hazardous waste is fed into the rotary kiln from the material inlet of the kiln head by a hydraulic push rod or other forms. A part of the combustion air enters the rotary kiln from the secondary air duct at the kiln head in the same direction (the same direction as the material), and the remaining combustion air enters the incineration chamber through the primary air duct, the annular air duct, and the kiln air duct, that is, the remaining combustion air enters the rotary kiln from the middle of the kiln body. The low-volatile organic hazardous waste entering the rotary kiln is first mixed with the combustion-supporting air in the pyrolysis chamber (i.e., the primary incineration section) and burned once, and then enters the incineration chamber (i.e., the secondary incineration section) to be mixed with the combustion-supporting air entering from the kiln body and further burned. The hot slag after the incineration is discharged from the rotary kiln through the material outlet at the end of the kiln, and the smoke after incineration is discharged from the rotary kiln through the air duct at the end of the kiln. That is, in the present invention, the downstream rotary kiln can be directly used with the original countercurrent rotary kiln through the combustion-supporting air and the smoke after incineration, and the original rotary kiln is converted into a downstream and countercurrent dual-purpose rotary kiln. The downstream rotary kiln is used to treat low-volatile organic hazardous waste, and the countercurrent rotary kiln is used to treat high-volatile organic hazardous waste, thereby increasing the adaptability of the rotary kiln to different materials.

[0070] As a preferred embodiment, the temperature-controlled and oxygen-controlled combustion system for the coordinated disposal of organic hazardous wastes according to the present invention further includes a sintering machine. The sintering machine is arranged downstream of the rotary kiln. Along the direction of the material, a lower-layer distribution machine, a middle-layer distribution machine, and an upper-layer distribution machine are sequentially arranged above the sintering trolley located in the feed section of the sintering machine (the specific number of distribution machines can be set according to the specific sintering process). The material outlet of the rotary kiln is connected to a lower-layer distribution machine, a middle-layer distribution machine or an upper-layer distribution machine. The present invention transports the incineration residue after the rotary kiln incinerates the hazardous waste to the sintering machine for disposal, and selectively distributes the incineration residue to the lower layer, middle layer or upper layer of the sintering trolley according to the degree of incineration of the organic hazardous waste and the residual organic matter in the incineration residue. The incineration residue completed in the rotary kiln is co-disposed of using the sintering process of the steel plant, which can effectively recover the iron element in the iron-containing solid waste, and the heavy metals in the residue are disposed of by the sintering process, completely eliminating the environmental impact of the solid waste and the risk of secondary pollution. Compared with the existing technology, the temperature and oxygen controlled incineration in the rotary kiln also allows the organic matter in the hazardous waste to be partially preserved and fully utilized in the sintering process, thereby improving the thermal energy utilization rate.

[0071] In the present invention, since the residue after incineration in the rotary kiln is transported to the sintering machine for co-processing, if the residue is too wet, it will have a significant impact on sintering production. Therefore, it must be dried before being added to the sintering machine. Based on this, the system of the present invention also includes a hot slag cooler disposed between the rotary kiln and the sintering machine. The hot slag cooler is a dry hot slag cooler, such as a partition-type heat exchanger. Compared with existing wet cooling, a dry hot slag cooler does not increase the humidity of the residue. The cooling medium used in the hot slag cooler can be air or water, depending on the heat exchange capacity or actual needs. If air is used as the cooling medium, the cold air enters the hot slag cooler and becomes hot air, which can then be fed into the rotary kiln through the kiln tail air duct as combustion air. If water is used as the cooling medium, the heated hot water can also be used as boiler feed water within the factory. Therefore, whether air or water is used as the cooling medium, heat energy recovery from the hot slag can be achieved.

[0072] In the present invention, a plurality of kiln air ducts are provided in the rotary kiln. The plurality of kiln air ducts are evenly distributed along the circumference of the rotary kiln, i.e., the plurality of kiln air ducts are evenly arranged in rotational symmetry within the rotary kiln. Each kiln air duct is connected to the annular air duct, i.e., each kiln air duct is connected to the primary air duct via the annular air duct. In actual production, the specific number and size of the kiln air ducts are determined based on the flue gas flow rate (or air volume) and the size of the rotary kiln. Generally speaking, the number of kiln air ducts can be 2-30, preferably 3-20, for example, 12, 16, or 20.

[0073] In order to facilitate the exhaust of flue gas after incineration in the counter-flow rotary kiln through the primary air duct and to circulate it into the rotary kiln through the secondary air duct, and also to facilitate the transportation of the combustion-supporting air of the downstream rotary kiln into the rotary kiln through the primary air duct and the secondary air duct respectively, the present invention provides a three-way valve at the position where the secondary air duct is divided on the primary air duct, and provides an exhaust device (such as an exhaust pump) on the secondary air duct to control the amount of flue gas circulating into the rotary kiln. In the downstream rotary kiln, the exhaust device can control the amount of combustion-supporting air entering the rotary kiln through the secondary air duct.

[0074] Based on the aforementioned rotary kiln-sintering machine temperature-controlled and oxygen-controlled combustion system for the coordinated treatment of organic hazardous waste, the present invention also proposes a corresponding method for the coordinated treatment of organic hazardous waste using temperature-controlled and oxygen-controlled combustion. When the material to be treated is high-volatile organic hazardous waste, the method for treating this waste is a method for the coordinated treatment of organic hazardous waste using temperature-controlled and oxygen-controlled combustion using a countercurrent rotary kiln-sintering machine. In this method, the high-volatile organic hazardous waste is organic hazardous waste having a mass percentage of volatile matter on a dry basis greater than or equal to H%, where H is 6-12, preferably 7-10. The method primarily includes the steps (or processes) of pyrolysis, incineration, flue gas recirculation, cooling, and sintering. In view of the fact that conventional rotary kilns typically employ incineration temperatures of 850-950°C, which can easily lead to slagging and agglomeration when treating organic hazardous waste with a high iron content in steel mills, this method adjusts and controls the temperature within the rotary kiln's incineration chamber (i.e., the main combustion zone) based on the iron content of the organic hazardous waste. The adjustment method is mainly to control the air volume and material volume entering the rotary kiln furnace, and adjust the heat supply of the heat supply burner when necessary. The basis for adjustment is the real-time combustion temperature in the rotary kiln incineration chamber and the real-time oxygen content and real-time combustible component content in the flue gas after incineration. Generally speaking, the normal oxygen content in flue gas is 6% to 10%. If it exceeds 10%, it means there is too much air (that is, the oxygen content is too high), and if it is less than 6%, it means there is insufficient air (that is, the oxygen content is too low). The content of combustible components in the flue gas should be as low as possible. If the combustible component content exceeds 5%, it means that the combustible component content is too high. In order to burn cleanly, usually the excessive content of combustible components and the excessive oxygen content will not occur at the same time, because oxygen and combustible components will react at high temperatures.

[0075] In the present invention, by controlling the oxygen content and temperature in the rotary kiln, the organic hazardous waste is incinerated below the low-temperature eutectic point, effectively alleviating the ringing and slagging phenomenon when the rotary kiln incinerates iron-containing organic solid waste, thereby improving the combustion efficiency. In the incineration process of the present invention, the specific strategy for adjusting the combustion temperature in the rotary kiln incineration chamber is as follows:

[0076] First, the iron content w of the high-volatile organic hazardous waste entering the rotary kiln is detected by the iron content detection device installed at the material inlet. The combustion temperature T0 that needs to be controlled in the incineration chamber can be determined based on the detected iron content of the material. Specifically:

[0077] When w>50%, T0 is 550~650℃.

[0078] When 25%<w≤50%, T0 is 650~750℃.

[0079] When 5%≤w≤25%, T0 is 750~850℃.

[0080] When w<5%, T0 is 850~950℃.

[0081] The temperature detection device then monitors the combustion temperature in the incineration chamber in real time. The detected real-time combustion temperature T is compared with the desired combustion temperature T0. If T = T0, the incineration process is operating normally. In other words, the combustion temperature in the incineration chamber does not need to be adjusted, and the temperature detection device can continue monitoring.

[0082] If T<T0, it means that the temperature in the incineration chamber is too low and needs to be increased. At this time, the real-time oxygen content and real-time combustible component content in the flue gas after incineration are detected by a gas analyzer.

[0083] If the gas analyzer detects that the real-time oxygen content in the flue gas after incineration is normal (i.e., the oxygen content is 6% to 10%) and the combustible component content is also normal (i.e., the combustible component content is ≤5%), this indicates that the heat in the incineration chamber itself is insufficient and a heat source is needed. Therefore, the heat supply can be supplemented by opening the supplementary heat burner at this time, so that T = T0. Alternatively, the feed rate in the rotary kiln can be increased (i.e., the amount of material entering the rotary kiln from the kiln head material inlet is increased) and the heat supply is increased by burning the incremental material. To ensure the combustion of the incremental fuel, the air intake in the rotary kiln can be increased at the same time (i.e., the amount of combustion-supporting air entering the rotary kiln from the kiln tail air duct is increased), ultimately achieving T = T0.

[0084] If the gas analyzer detects a low real-time oxygen content in the flue gas after incineration (i.e., an oxygen content of less than 6%), regardless of the level of combustible components at this time, it indicates that the oxygen required for the reaction in the incineration chamber is insufficient. Considering the need to increase the combustion temperature in the incineration chamber, the air flow into the rotary kiln can be increased to increase the oxygen content, and the feed rate into the rotary kiln can be increased to ensure a temperature increase, so that T = T0. Alternatively, if temperature control is the primary concern, additional heat can be added by turning on the supplementary heat burner to achieve T = T0.

[0085] If the gas analyzer detects a high real-time oxygen content in the flue gas after incineration (i.e., oxygen content > 10%) and a normal real-time combustible component content, it indicates that the combustible components in the incineration chamber have been essentially burned out. A low temperature in the incineration chamber may be due to insufficient heat in the kiln or excessive heat absorption by the combustion-supporting air. Therefore, the air flow into the rotary kiln can be reduced, the feed rate can be increased, or the supplemental heat burner can be activated to ultimately achieve T = T0.

[0086] If T>T0, it means that the temperature in the incineration chamber is too high and needs to be lowered. At this time, the real-time oxygen content and real-time combustible component content in the flue gas after incineration are detected by a gas analyzer.

[0087] If the gas analyzer detects normal real-time oxygen and combustible component content in the flue gas after incineration, it indicates that the current combustion is under equivalence ratio combustion conditions, the combustion conditions are very good, and there is excess heat in the kiln. Therefore, the heat supply of the supplementary heat burner can be directly reduced, or the feed rate to the rotary kiln can be reduced, while the air flow rate to the rotary kiln is also reduced to achieve T = T0.

[0088] If the gas analyzer detects a low real-time oxygen content in the flue gas after incineration, it indicates an excess of fuel and insufficient air. Considering the need to lower the combustion temperature in the incineration chamber, the air flow into the rotary kiln can be increased to increase the oxygen content, while the feed rate can be reduced to ensure a lower temperature, so that T = T0. Alternatively, if temperature control is the primary concern, the heat added by the supplemental heat burner can be reduced to achieve T = T0.

[0089] If the gas analyzer detects a high real-time oxygen content in the flue gas after incineration, but a normal real-time combustible component content, this indicates an excess of air and heat in the kiln. Therefore, the air flow into the rotary kiln can be reduced to lower the oxygen content, while the feed rate can be reduced to reduce the heat input, thereby ensuring a lower temperature, such that T = T0. Alternatively, T = T0 can be achieved by directly reducing the heat added by the supplemental heat burners.

[0090] It should be noted that during the incineration process, when the oxygen content is normal, there is also 6% to 10% oxygen, which is sufficient for complete combustion. Therefore, in theory, if the content of combustible components is too high, the oxygen content will not be normal (even below 3%). Therefore, under normal conditions, the situation where the oxygen content is normal and the content of combustible components is too high generally does not occur.

[0091] According to the above-mentioned temperature adjustment strategy, after adjusting the combustion temperature according to the iron content of the material, since the rotation speed of the rotary kiln remains unchanged, theoretically the residence time of the material in the kiln will not change significantly. Compared with the existing technology, after the combustion temperature drops, the hazardous waste residue may be insufficiently incinerated and organic matter may remain. And in theory, the lower the temperature, the more organic matter remains in the residue, which cannot meet the requirement of the existing incineration technology that the residue ignition rate is less than 5%. However, the requirement of the existing incineration technology of "residue ignition rate less than 5%" is based on the current situation where incineration residues are generally used for safe landfill. In this technical solution, since the incineration residue continues to enter the sintering system for disposal, its residual organic matter can be used in sintering, and the residue can be graded and utilized according to the different amounts of organic matter remaining in the residue.

[0092] Practical experience shows that incineration residues at temperatures above 850°C essentially eliminate organic matter, leaving only the iron resources available for sintering and utilization, thus becoming carbon-free residues. Incineration residues at temperatures below 650°C contain significant amounts of organic matter, exceeding 5%, resulting in high-carbon residues. Incineration residues at temperatures between 650°C and 850°C have a relatively low organic content, falling between high-carbon residues and carbon-free residues, thus becoming low-carbon residues.

[0093] In other words, different iron content of materials corresponds to different combustion temperatures, and different combustion temperatures correspond to different types of residues after incineration. Specifically:

[0094] When T0 is 550-650°C, the cold slag obtained after incineration is completed and cooled is a high-carbon residue.

[0095] When T0 is 650-850°C, the cold slag obtained after incineration is completed and cooled is a low-carbon residue.

[0096] When T0 is 850-950°C, the cold slag obtained after incineration is completed and cooled is a carbon-free residue.

[0097] Figure 5 This is a structural diagram of the sintering machine for the coordinated disposal of organic hazardous waste in the present invention. The sintering trolley located in the feeding section of the sintering machine is equipped with lower, middle and upper distribution machines in sequence. Along the running direction of the sintering trolley, the downstream of the distribution machine is the ignition and holding furnace. The lower part of the sintering machine is provided with a sintering main exhaust fan, and the sintering trolley is not shown in the figure. In the existing sintering production, due to the exhaust effect of the main exhaust fan during the movement of the sintering trolley, there is a heat storage effect in the lower layer of sintering material, that is, the heat distribution is more at the bottom and less at the top, which may result in insufficient heat in the upper layer and more raw materials, while the lower layer of material is over-melted due to too much heat, and even due to too much heat in the lower layer, the trolley grate bars may be burned.

[0098] Based on the above sintering principles and practical experience, the utilization of incineration residues can be achieved by placing carbon-free residue in the lower-layer feeder. This carbon-free residue acts as a base material, effectively reducing the heat in the lower layer and protecting the trolley grate. Low-carbon residue can be mixed with the sintering raw materials and placed in the middle-layer feeder, where it co-mineralizes with the raw materials. High-carbon residue can be placed in the upper-layer feeder to increase the heat in the upper layer and improve ignition. This layered distribution can alleviate the uneven heat distribution in the original sintering layer, effectively reducing energy consumption and minimizing sintering return.

[0099] It should be noted that the countercurrent incineration rotary kiln in the aforementioned solution is designed for high-volatile, high-iron hazardous waste. However, the system described in the present invention is dual-purpose. Using the same equipment, without any changes to the system itself, the rotary kiln can also be converted into a downstream rotary kiln for incinerating low-volatile hazardous waste. Because low-volatile hazardous waste itself is not highly volatile, if it undergoes pyrolysis, it will not produce much volatile matter, so there is little point in first passing it through the pyrolysis stage. Changing to a downstream rotary kiln expands the applicability of the system of the present invention to the hazardous waste being incinerated.

[0100] When the material to be treated is low-volatile organic hazardous waste, the method for disposing of this waste is a method for co-processing organic hazardous waste using temperature- and oxygen-controlled combustion in a downstream rotary kiln-sintering machine. In this method, the low-volatile organic hazardous waste is organic hazardous waste with a dry-weight volatile matter content of less than or equal to H%. Where H is 6-12, preferably 7-10. Because this method does not require a pyrolysis stage, it primarily includes steps (or processes) such as primary incineration, secondary incineration, cooling, and sintering.

[0101] When burning low volatile organic hazardous waste, such as Figure 7 As shown, the primary air duct is changed from the exhaust channel of the flue gas after incineration to the channel for the combustion air to enter the rotary kiln, and the secondary air duct is changed from the circulating flue gas channel to another channel for the combustion air to enter the rotary kiln. At this time, the source of the combustion air can still be the heat medium (i.e. hot air or hot wind) discharged from the hot slag cooler. Among them, the secondary air duct transports the combustion air from the kiln head to the rotary kiln, and the primary air duct transports the combustion air from the kiln body to the rotary kiln through the annular air duct and the kiln air duct. The kiln tail air duct is changed from the channel for the combustion air to enter the rotary kiln to the exhaust channel of the flue gas after incineration. That is, the use of Figure 7When using the downstream rotary kiln shown above to dispose of low-volatile organic hazardous waste, the only requirement is to reverse the direction of the flue gas and air in the primary and tail air ducts, based on the aforementioned countercurrent rotary kiln. This now transforms the countercurrent rotary kiln into a downstream rotary kiln (i.e., the material flow and the combustion air flow are the same). Low-volatile organic hazardous waste continues to enter the rotary kiln through the material inlet at the kiln head, while primary air enters the pyrolysis chamber of the rotary kiln through the secondary air duct at the kiln head. The low-volatile organic hazardous waste and combustion air undergo a single combustion process within the pyrolysis chamber. The primary air ratio is controlled to be between 0.3 and 0.4 of the theoretical air volume required in the kiln, adjusted by the exhaust pump in the secondary air duct. The remaining air, in the form of secondary air, passes through the primary air duct, the annular air duct, and the kiln air duct into the incineration chamber of the kiln body for further incineration. The incinerated residue is discharged through the material outlet at the kiln tail and cooled in a hot slag cooler. The incinerated flue gas is discharged through the kiln tail duct. After cooling, the cold slag is transported to the sintering process for utilization. The functions of the remaining components in the rotary kiln are the same as those of the aforementioned countercurrent rotary kiln. The secondary combustion section corresponding to the incineration chamber is the main combustion zone, and its temperature adjustment also needs to adjust the temperature of the main combustion zone according to the iron content of the material. The original temperature adjustment rules still apply.

[0102] In the present invention, the downstream rotary kiln is directly converted from the original countercurrent rotary kiln through the air and flue gas reversal. The downstream rotary kiln changes the original external heat flue gas heat exchange pipe (i.e., the air duct in the kiln) into a secondary air supply pipe, realizing secondary air intake into the kiln body, changing the original combustion-supporting air from the kiln head, resulting in intense combustion at the kiln head and high temperature, and less air and low temperature at the kiln tail. That is, the secondary air intake of the kiln body reduces the air intake at the kiln head, lowers the kiln head temperature, and increases the kiln tail temperature, making the temperature distribution of the rotary kiln more uniform, and also conducive to the reduction of nitrogen oxides.

[0103] Compared with the prior art, the present invention has the following beneficial technical effects:

[0104] 1. The present invention proposes a dual-purpose rotary kiln of co-current and counter-current types, which adopts different combustion modes for different raw materials. Co-current is used to incinerate low-volatile organic hazardous waste, while counter-current is used to incinerate high-volatile organic hazardous waste, thereby expanding the adaptability of the rotary kiln to different materials.

[0105] 2. The present invention proposes a two-stage countercurrent incineration rotary kiln for pyrolysis-incineration of high-volatile organic hazardous waste. By controlling the oxygen content and temperature in the rotary kiln, the organic hazardous waste is incinerated below the low-temperature eutectic point, effectively alleviating the ringing and slagging phenomenon when the rotary kiln incinerates iron-containing organic solid waste, thereby improving the combustion efficiency.

[0106] 3. This invention utilizes the rotary kiln's incineration residues for co-processing within the steel mill's sintering process, effectively recovering the iron from the iron-containing solid waste. Heavy metals in the residue are disposed of by the sintering process, completely eliminating the environmental impact of the solid waste and the risk of secondary pollution. Compared to existing technologies, the temperature- and oxygen-controlled incineration in the rotary kiln also partially preserves organic matter from the hazardous waste, fully utilizing it in the sintering process and improving thermal energy efficiency.

[0107] 4. The sintering process of the present invention utilizes the residues after incineration at different temperatures in a step-by-step manner and distributes the materials in layers, thereby alleviating the heat storage effect of the existing sintering material layer, promoting uniform sintering, and improving the sintering quality.

[0108] 5. In the present invention, the downstream rotary kiln is directly converted from the original countercurrent rotary kiln through the air and flue gas reversal. The downstream rotary kiln converts the original external heat flue gas heat exchange pipe into a secondary air supply pipe, realizing secondary air intake into the kiln body, changing the original combustion air entering from the kiln head, resulting in intense combustion and high temperature at the kiln head, less air and low temperature at the kiln tail, that is, the secondary air intake of the kiln body reduces the air intake at the kiln head, lowers the kiln head temperature, and increases the kiln tail temperature, making the distribution of the rotary kiln more uniform, and also conducive to the reduction of nitrogen oxides. BRIEF DESCRIPTION OF THE DRAWINGS

[0109] Figure 1 This is a schematic diagram of the structure of a hazardous waste incineration rotary kiln in the prior art;

[0110] Figure 2 Schematic diagram of the structure of the countercurrent rotary kiln for treating high-volatile organic hazardous waste in the present invention;

[0111] Figure 3 for Figure 2 Cross-section along the AA direction;

[0112] Figure 4 for Figure 2 Cross-section along the mid-BB direction;

[0113] Figure 5 This is a schematic structural diagram of a sintering machine for collaboratively treating hazardous organic waste in the present invention;

[0114] Figure 6 Schematic diagram of the structure of the countercurrent rotary kiln-sintering machine collaborative treatment system for hazardous organic waste in the present invention;

[0115] Figure 7 This is a schematic structural diagram of a downstream rotary kiln for treating low-volatile organic hazardous waste in the present invention;

[0116] Figure 8 The present invention is a flow chart of the method for adjusting the incineration temperature in the rotary kiln.

[0117] Reference numerals:

[0118] C1: Rotary kiln; 1: Kiln head; 101: Material inlet; 2: Kiln body; 201: Furnace lining; 202: Furnace chamber; 20201: Pyrolysis chamber; 20202: Incineration chamber; 3: Kiln tail; 301: Material outlet; 302: Kiln tail air duct; 303: Supplementary heat burner; 4: Kiln air duct; 5: Annular air duct; 6: Primary air duct; 7: Secondary air duct; C2: Sintering machine; 801: Lower layer charge distributor; 802: Middle layer charge distributor; 803: Upper layer charge distributor; 9: Hot slag cooler; 901: Hot slag inlet; 902: Cold slag outlet; 903: Cold medium inlet; 904: Hot medium outlet; 10: Three-way valve; 11: Exhaust device; 12: Temperature detection device; 13: Material iron content detection device; 14: Gas analyzer. DETAILED DESCRIPTION

[0119] The technical solutions of the present invention are illustrated below with examples, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0120] According to a first embodiment of the present invention, a system for co-processing organic hazardous wastes by temperature-controlled and oxygen-controlled combustion is provided.

[0121] A system for the coordinated disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, the system comprising a rotary kiln C1. The rotary kiln C1 comprises a kiln head 1, a kiln body 2, and a kiln tail 3. The kiln head 1 is provided with a material inlet 101. The kiln body 2 comprises a furnace lining 201 and a furnace 202. The kiln tail 3 is provided with a material outlet 301 and a kiln tail air duct 302. Along the flow of the material, the furnace 202 is divided into a pyrolysis chamber 20201 and an incineration chamber 20202. A kiln air duct 4 is provided inside the furnace lining 201 corresponding to the pyrolysis chamber 20201. One end of the kiln air duct 4 extends into the kiln head 1, and the other end is connected to the incineration chamber 20202. An annular air duct 5 is also provided on the kiln head 1. The kiln air duct 4 is connected to a primary air duct 6 arranged outside the rotary kiln C1 via the annular air duct 5. A secondary air duct 7 is branched from the primary air duct 6. The secondary air duct 7 passes through the kiln head 1 and is connected to the pyrolysis chamber 20201.

[0122] In the present invention, the system also includes a sintering machine C2, located downstream of the rotary kiln C1. Along the material flow path, above the sintering trolleys in the feed section of the sintering machine C2, are positioned a lower-level material distributor 801, a middle-level material distributor 802, and an upper-level material distributor 803. The material outlet 301 of the rotary kiln C1 is connected to the lower-level material distributor 801, the middle-level material distributor 802, or the upper-level material distributor 803.

[0123] In the present invention, the system also includes a hot slag cooler 9 disposed between the rotary kiln C1 and the sintering machine C2. The hot slag cooler 9 is provided with a hot slag inlet 901, a cold slag outlet 902, a cold medium inlet 903, and a hot medium outlet 904. The material outlet 301 of the rotary kiln C1 is connected to the hot slag inlet 901 of the hot slag cooler 9. The cold slag outlet 902 of the hot slag cooler 9 is connected to the lower-layer material distributor 801, the middle-layer material distributor 802, or the upper-layer material distributor 803 of the sintering machine C2. Preferably, the hot slag cooler 9 is a dry-type hot slag cooler, preferably a partition-type heat exchanger.

[0124] Preferably, the rotary kiln C1 is provided with n kiln air ducts 4. The n kiln air ducts 4 are evenly distributed along the circumference of the rotary kiln C1. Each kiln air duct 4 is connected to an annular air duct 5 provided at the kiln head 1. Wherein: n is 2-30, preferably 3-20.

[0125] Preferably, a three-way valve 10 is provided at the location where the primary air duct 6 branches off into the secondary air duct 7. An air extraction device 11 is provided on the secondary air duct 7. Preferably, a supplementary heat burner 303 is further provided on the kiln tail 3 of the rotary kiln C1.

[0126] Preferably, a temperature detection device 12 is provided in the combustion chamber 20202 of the rotary kiln C1. A material iron content detection device 13 is provided at the material inlet 101 of the kiln head 1. A gas analyzer 14 is provided on the primary air duct 6, near the annular air duct 5.

[0127] Example 1

[0128] like Figure 2-3 As shown, a system for co-processing organic hazardous waste by temperature-controlled and oxygen-controlled combustion includes a rotary kiln C1. The rotary kiln C1 includes a kiln head 1, a kiln body 2, and a kiln tail 3. The kiln head 1 is provided with a material inlet 101. The kiln body 2 includes a furnace lining 201 and a furnace 202. The kiln tail 3 is provided with a material outlet 301 and a kiln tail air duct 302. Along the flow of the material, the furnace 202 is divided into a pyrolysis chamber 20201 and an incineration chamber 20202. A kiln air duct 4 is provided inside the furnace lining 201 corresponding to the pyrolysis chamber 20201. One end of the kiln air duct 4 extends into the kiln head 1, and the other end is connected to the incineration chamber 20202. An annular air duct 5 is also provided on the kiln head 1. The kiln air duct 4 is connected to a primary air duct 6 arranged outside the rotary kiln C1 through the annular air duct 5. A secondary air duct 7 is branched from the primary air duct 6. The secondary air duct 7 passes through the kiln head 1 and is connected to the pyrolysis chamber 20201.

[0129] Example 2

[0130] like Figure 5As shown, Example 1 is repeated, except that the system also includes a sintering machine C2 located downstream of the rotary kiln C1. Along the material flow path, a lower-level material distributor 801, a middle-level material distributor 802, and an upper-level material distributor 803 are located above the sintering trolley in the feed section of sintering machine C2. The material outlet 301 of rotary kiln C1 is connected to the upper-level material distributor 803.

[0131] Example 3

[0132] Example 1 was repeated, except that the system also included a sintering machine C2 located downstream of the rotary kiln C1. Along the material flow path, a lower-level material distributor 801, a middle-level material distributor 802, and an upper-level material distributor 803 were positioned above the sintering trolley in the feed section of sintering machine C2. The material outlet 301 of rotary kiln C1 was connected to the lower-level material distributor 801.

[0133] Example 4

[0134] Example 1 was repeated, except that the system also included a sintering machine C2 located downstream of the rotary kiln C1. Along the material flow path, above the sintering trolleys in the feed section of sintering machine C2, a lower-level material distributor 801, a middle-level material distributor 802, and an upper-level material distributor 803 were installed. The material outlet 301 of rotary kiln C1 was connected to the middle-level material distributor 802.

[0135] Example 5

[0136] like Figure 6 As shown, Example 2 is repeated, except that the system further includes a hot slag cooler 9 disposed between the rotary kiln C1 and the sintering machine C2. The hot slag cooler 9 is provided with a hot slag inlet 901, a cold slag outlet 902, a cold medium inlet 903, and a hot medium outlet 904. The material outlet 301 of the rotary kiln C1 is connected to the hot slag inlet 901 of the hot slag cooler 9. The cold slag outlet 902 of the hot slag cooler 9 is connected to the upper material distributor 803 of the sintering machine C2.

[0137] Example 6

[0138] Example 5 is repeated, except that the hot slag cooler 9 is a partition-type heat exchanger.

[0139] Example 7

[0140] Example 6 was repeated, except that the rotary kiln C1 was provided with four kiln air ducts 4. The four kiln air ducts 4 were evenly distributed along the circumference of the rotary kiln C1. Each kiln air duct 4 was connected to the annular air duct 5 provided at the kiln head 1.

[0141] Example 8

[0142] like Figure 4As shown, Example 6 is repeated, except that the rotary kiln C1 is provided with 16 kiln air ducts 4. The 16 kiln air ducts 4 are evenly distributed along the circumference of the rotary kiln C1. Each kiln air duct 4 is connected to the annular air duct 5 provided at the kiln head 1.

[0143] Example 9

[0144] The embodiment 8 is repeated except that a three-way valve 10 is provided at the position where the primary air duct 6 branches off into the secondary air duct 7. An air extraction device 11 is provided on the secondary air duct 7.

[0145] Example 10

[0146] Example 9 is repeated, except that a supplementary heat burner 303 is further provided on the kiln tail 3 of the rotary kiln C1.

[0147] Example 11

[0148] Example 10 was repeated except that a temperature detection device 12 was installed in the combustion chamber 20202 of the rotary kiln C1. A material iron content detection device 13 was installed at the material inlet 101 of the kiln head 1. A gas analyzer 14 was installed on the primary air duct 6 near the annular air duct 5.

[0149] Example 12

[0150] A method for co-disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, using the system described in Example 1, comprising the following steps:

[0151] 1) Pyrolysis: Highly volatile organic hazardous waste is delivered to the rotary kiln C1 via the material inlet 101 at the kiln head 1. Combustion air enters the rotary kiln C1 via the kiln tail air duct 302. The high-volatile organic hazardous waste first enters the pyrolysis chamber 20201 of the rotary kiln C1 for drying and pyrolysis. After pyrolysis, the residual material and pyrolysis gases enter the incineration chamber 20202.

[0152] 2) Incineration: Material residue, pyrolysis gases, and combustion air are mixed and burned in the incineration chamber 20202. After incineration, the hot slag is discharged from the rotary kiln C1 through the material outlet 301 at the kiln tail 3. The incinerated flue gas is discharged from the rotary kiln C1 through the kiln air duct 4, the annular air duct 5, and the primary air duct 6.

[0153] 3) Flue gas circulation: Part of the flue gas that enters the primary air duct 6 in step 2) enters the rotary kiln C1 again through the secondary air duct 7 and completes the pyrolysis and incineration process together with the material in the rotary kiln C1.

[0154] Example 13

[0155] A method for co-disposal of organic hazardous waste by temperature-controlled and oxygen-controlled combustion, using the system described in Example 11, comprising the following steps:

[0156] 1) Pyrolysis: Highly volatile organic hazardous waste is delivered to the rotary kiln C1 via the material inlet 101 at the kiln head 1. Combustion air enters the rotary kiln C1 via the kiln tail air duct 302. The high-volatile organic hazardous waste first enters the pyrolysis chamber 20201 of the rotary kiln C1 for drying and pyrolysis. After pyrolysis, the residual material and pyrolysis gases enter the incineration chamber 20202.

[0157] 2) Incineration: Material residue, pyrolysis gases, and combustion air are mixed and burned in the incineration chamber 20202. After incineration, the hot slag is discharged from the rotary kiln C1 through the material outlet 301 at the kiln tail 3. The incinerated flue gas is discharged from the rotary kiln C1 through the kiln air duct 4, the annular air duct 5, and the primary air duct 6.

[0158] 3) Flue gas circulation: Part of the flue gas that enters the primary air duct 6 in step 2) enters the rotary kiln C1 again through the secondary air duct 7 and completes the pyrolysis and incineration process together with the material in the rotary kiln C1.

[0159] 4) Cooling: The hot slag discharged from the rotary kiln C1 in step 2) is transported to a hot slag cooler 9, and a cooling medium is introduced into the hot slag cooler 9. The hot slag and the cooling medium exchange heat within the hot slag cooler 9, resulting in cold slag and a hot medium.

[0160] 5) Sintering: Place the cold slag obtained in step 4) and the sintering raw materials on a sintering trolley and ignite and sinter.

[0161] Example 14

[0162] Example 13 was repeated, except that the high-volatile organic hazardous waste was an organic hazardous waste having a mass percentage of volatile matter on a dry basis greater than or equal to H%, where H is 6.

[0163] Example 15

[0164] Example 14 was repeated except that H was 8.

[0165] Example 16

[0166] Example 14 was repeated, except that in step 4), the cooling medium introduced into the hot slag cooler 9 was cold air. The cold air was converted into hot air after heat exchange in the hot slag cooler 9 and then discharged from the hot medium outlet 904. This hot air was then transported as combustion-supporting air to the kiln tail air duct 302 of the rotary kiln C1.

[0167] Example 17

[0168] Example 14 was repeated, except that in step 4), the cooling medium introduced into the hot slag cooler 9 was cooling water. The cooling water was converted into hot water after heat exchange in the hot slag cooler 9, and then discharged from the hot medium outlet 904. This hot water was used as boiler feed water.

[0169] Example 18

[0170] Example 16 was repeated, except that in step 2), the iron content w of the high-volatile organic hazardous waste entering the rotary kiln C1 was detected by the material iron content detection device 13. The combustion temperature T0 to be controlled in the incineration chamber 20202 was determined based on the detected material iron content. Specifically:

[0171] When w>50%, the temperature range of T0 is 550~650℃.

[0172] When 25%<w≤50%, the temperature range of T0 is 650~750℃.

[0173] When 5%≤w≤25%, the temperature range of T0 is 750~850℃.

[0174] When w<5%, the temperature range of T0 is 850~950℃.

[0175] Example 19

[0176] Example 18 was repeated, except that in step 1), the pyrolysis temperature in the pyrolysis chamber 20201 of the rotary kiln C1 was 400°C.

[0177] Example 20

[0178] Example 18 was repeated, except that in step 1), the pyrolysis temperature in the pyrolysis chamber 20201 of the rotary kiln C1 was 350°C.

[0179] Example 21

[0180] Repeat Example 19, except that the type of cold slag obtained in step 4) is determined based on the combustion temperature T0 that needs to be controlled in the incineration chamber 20202 in step 2). Specifically:

[0181] When the temperature range of T0 is 550-650°C, the cold slag obtained in step 4) is a high-carbon residue.

[0182] When the temperature range of T0 is 650-850°C, the cold slag obtained in step 4) is a low-carbon residue.

[0183] When the temperature range of T0 is 850-950°C, the cold slag obtained in step 4) is a carbon-free residue.

[0184] The organic matter content of the high carbon residue is greater than Z%, and the organic matter content of the low carbon residue is less than or equal to Z%, wherein Z is 5.

[0185] Example 22

[0186] Example 21 was repeated, except that the cold slag type was obtained according to step 4). Step 5) was specifically as follows:

[0187] When the cold slag obtained in step 4) is high-carbon residue, the high-carbon residue is placed in the upper distribution machine 803 on the sintering machine C2, that is, the sintering raw material is distributed to the sintering trolley, and then the high-carbon residue is distributed above the sintering raw material by the upper distribution machine 803, and ignited and sintered.

[0188] When the cold slag obtained in step 4) is low-carbon residue, the sintering mixture obtained by mixing the low-carbon residue with the sintering raw materials is placed in the middle-layer distribution machine 802 on the sintering machine C2, and then the sintering mixture is distributed to the sintering trolley through the middle-layer distribution machine 802 and ignited for sintering.

[0189] When the cold slag obtained in step 4) is carbon-free residue, the carbon-free residue is placed in the lower distribution machine 801 on the sintering machine C2. The carbon-free residue is distributed as a base material to the sintering trolley through the lower distribution machine 801, and then the sintering raw material is distributed above the base material and ignited for sintering.

[0190] Example 23

[0191] Example 22 is repeated, except that in the incineration process of step 2), when the material residue, pyrolysis gas and combustion-supporting air are burned, the temperature changes in the incineration chamber 20202 are monitored in real time, and the oxygen content and combustible component content in the flue gas after incineration are monitored in real time, and then the air intake and feed amount in the rotary kiln C1 and the heat supply of the heat supply burner 303 are adjusted, thereby achieving control of the process conditions of the incineration process and controlling the combustion temperature in the incineration chamber 20202.

[0192] Example 24

[0193] like Figure 8 As shown, Example 23 is repeated, except that the process conditions of the incineration process are controlled to control the combustion temperature in the incineration chamber 20202, which specifically includes the following sub-steps:

[0194] 201) As the material residue, pyrolysis gas, and combustion air burn, the temperature detection device 12 monitors the combustion temperature in the incineration chamber 20202 in real time. During the real-time monitoring process, the detected real-time combustion temperature T in the incineration chamber 20202 is compared with the desired combustion temperature T0 in the incineration chamber 20202.

[0195] 201a) If the real-time combustion temperature T in the incineration chamber 20202 = the combustion temperature T0 to be controlled, that is, the incineration process is operating normally at this time, the temperature detection device 12 continues to monitor.

[0196] 201b) If the real-time combustion temperature T in the combustion chamber 20202 is less than the desired combustion temperature T0, the temperature in the combustion chamber 20202 needs to be increased. At this time, the gas analyzer 14 is used to detect the real-time oxygen content and the real-time combustible component content in the flue gas after combustion.

[0197] If it is detected that the real-time oxygen content and the combustible component content in the flue gas after incineration are normal, the supplementary heat burner 303 is turned on so that T=T0.

[0198] If it is detected that the real-time oxygen content in the flue gas after incineration is low, the air flow rate in the rotary kiln C1 is increased, and the feed rate in the rotary kiln A1 is increased at the same time, so that T=T0.

[0199] If it is detected that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal, the air inlet volume in the rotary kiln C1 is reduced so that T=T0.

[0200] 201c) If the real-time combustion temperature T in the combustion chamber 20202 is greater than the desired combustion temperature T0, the temperature in the combustion chamber 20202 needs to be lowered. At this time, the gas analyzer 14 is used to detect the real-time oxygen content and the real-time combustible component content in the flue gas after combustion.

[0201] If it is detected that the real-time oxygen content and the combustible component content in the flue gas after incineration are normal, the heat supply of the heat supply burner 303 is reduced so that T=T0.

[0202] If it is detected that the real-time oxygen content in the flue gas after incineration is low, the air flow rate in the rotary kiln C1 is increased, and the feed rate in the rotary kiln C1 is reduced, so that T=T0.

[0203] If it is detected that the real-time oxygen content in the flue gas after incineration is too high and the real-time combustible component content is normal, the air flow into the rotary kiln C1 is reduced, and the feed amount into the rotary kiln C1 is reduced at the same time, so that T=T0.

[0204] Example 25

[0205] Example 24 is repeated, except that in step 201b), if the real-time oxygen content and combustible component content in the flue gas after incineration are detected to be normal, the feed amount in the rotary kiln C1 is increased, and the air intake in the rotary kiln C1 is increased at the same time, so that T=T0.

[0206] Example 26

[0207] Repeat Example 24, except that in step 201b), if it is detected that the real-time oxygen content in the flue gas after incineration is low, the supplementary heat burner 303 is turned on so that T=T0.

[0208] Example 27

[0209] Example 24 is repeated, except that in step 201b), if it is detected that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal, the feed rate in the rotary kiln C1 is increased so that T=T0.

[0210] Example 28

[0211] Repeat Example 24, except that in step 201b), if it is detected that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal, the supplementary heat burner 303 is turned on so that T=T0.

[0212] Example 29

[0213] Repeat Example 24, except that in step 201c), if the real-time oxygen content and combustible component content in the flue gas after incineration are detected to be normal, the feed amount in the rotary kiln C1 is reduced, and the air intake in the rotary kiln C1 is also reduced so that T=T0.

[0214] Example 30

[0215] Repeat Example 24, except that in step 201c), if it is detected that the real-time oxygen content in the flue gas after incineration is low, the heat supply of the heat supply burner 303 is reduced so that T=T0.

[0216] Example 31

[0217] Repeat Example 24, except that in step 201c), if it is detected that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal, the heat supply of the heat supply burner 303 is reduced so that T=T0.

[0218] Example 32

[0219] A method for co-processing organic hazardous wastes by temperature-controlled oxygen-controlled combustion, using the system described in Example 11, wherein the rotary kiln C1 in the system is as follows: Figure 7 As shown, the method includes the following steps:

[0220] a) Low-volatile organic waste is delivered to the rotary kiln C1 through the material inlet 101 of the kiln head 1. Combustion air enters the rotary kiln C1 through the secondary air duct 7 of the kiln head 1. The low-volatile organic waste and the combustion air mix and burn in the furnace 202.

[0221] b) After the incineration, the hot slag is discharged from the rotary kiln C1 through the material outlet 301 at the kiln tail 3. The smoke after the incineration is discharged from the rotary kiln C1 through the kiln tail air duct 302.

[0222] c) The hot slag discharged from the rotary kiln C1 in step b) is transported to a hot slag cooler 9, and a cooling medium is introduced into the hot slag cooler 9. The hot slag and the cooling medium exchange heat in the hot slag cooler 9, and after the heat exchange is completed, cold slag and hot medium are obtained.

[0223] d) placing the cold slag obtained in step c) and the sintering raw materials on a sintering trolley and igniting and sintering.

[0224] Example 33

[0225] Example 32 was repeated, except that the low-volatile organic hazardous waste was an organic hazardous waste having a dry-base volatile matter content of less than H%, where H is 7.

[0226] Example 34

[0227] Example 33 was repeated except that H was 10.

[0228] Example 35

[0229] Example 33 is repeated, except that in step a), the combustion-supporting air also enters the incineration chamber 20202 of the rotary kiln C1 through the primary air duct 6, the annular air duct 5, and the kiln air duct 4.

[0230] Example 36

[0231] Example 35 was repeated, except that the amount of combustion-supporting air entering the rotary kiln C1 through the secondary air duct 7 accounted for 30% of the total air volume required in the rotary kiln C1.

[0232] Example 37

[0233] Example 35 was repeated, except that the amount of the combustion-supporting air entering the rotary kiln C1 through the secondary air duct 7 accounted for 40% of the total air volume required in the rotary kiln C1.

[0234] Application Example 1

[0235] A method for co-processing organic hazardous waste by temperature-controlled and oxygen-controlled combustion, the method comprising the following steps:

[0236] 1) Pyrolysis: Highly volatile organic hazardous waste is delivered to the rotary kiln C1 via the material inlet 101 at the kiln head 1. Combustion air enters the rotary kiln C1 via the kiln tail air duct 302. The high-volatile organic hazardous waste first enters the pyrolysis chamber 20201 of the rotary kiln C1 for drying and pyrolysis. After pyrolysis, the residual material and pyrolysis gases enter the incineration chamber 20202.

[0237] 2) Incineration: Material residue, pyrolysis gases, and combustion air are mixed and burned in the incineration chamber 20202. After incineration, the hot slag is discharged from the rotary kiln C1 through the material outlet 301 at the kiln tail 3. The incinerated flue gas is discharged from the rotary kiln C1 through the kiln air duct 4, the annular air duct 5, and the primary air duct 6.

[0238] 3) Flue gas circulation: Part of the flue gas that enters the primary air duct 6 in step 2) enters the rotary kiln C1 again through the secondary air duct 7 and completes the pyrolysis and incineration process together with the material in the rotary kiln C1.

[0239] 4) Cooling: The hot slag discharged from the rotary kiln C1 in step 2) is transported to a hot slag cooler 9, and a cooling medium is introduced into the hot slag cooler 9. The hot slag and the cooling medium exchange heat within the hot slag cooler 9, resulting in cold slag and a hot medium.

[0240] 5) Sintering: Place the cold slag obtained in step 4) and the sintering raw materials on a sintering trolley and ignite and sinter.

[0241] In the incineration process of step 2), when the material residue, pyrolysis gas, and combustion air are burned, the temperature changes in the incineration chamber 20202 are monitored in real time, and the oxygen content and combustible component content in the flue gas after incineration are monitored in real time. The air inlet and feed amount in the rotary kiln C1, as well as the heat supply of the heat supply burner 303, are then adjusted to control the process conditions of the incineration process and the combustion temperature in the incineration chamber 20202. This specifically includes the following sub-steps:

[0242] 201) As the material residue, pyrolysis gas, and combustion air burn, the temperature detection device 12 monitors the combustion temperature in the incineration chamber 20202 in real time. During the real-time monitoring process, the detected real-time combustion temperature T in the incineration chamber 20202 is compared with the desired combustion temperature T0 in the incineration chamber 20202.

[0243] The iron content w of the high-volatile organic hazardous waste entering the rotary kiln C1 is detected by the material iron content detection device 13 to be 34%. The combustion temperature T0 to be controlled in the incineration chamber 20202 is determined to be 680°C based on the detected material iron content.

[0244] The real-time combustion temperature T in the incineration chamber 20202 detected by the temperature detection device 12 is 680° C., and it is obvious that T=T0, that is, the incineration process is running normally at this time, and the temperature detection device 12 continues to monitor.

[0245] Since T0 = 680°C, the cold slag obtained in step 4) is low-carbon residue at this time. Therefore, the sintering process described in step 5) is specifically as follows: the low-carbon residue obtained in step 4) is mixed with the sintering raw materials to form a sintering mixture, which is placed in the middle-layer distribution machine 802 of the sintering machine C2. The sintering mixture is then distributed to the sintering trolley by the middle-layer distribution machine 802 and ignited for sintering. Mixing the low-carbon residue with the sintering raw materials and then distributing it to the middle layer of the sintering material allows the low-carbon residue and the sintering raw materials to undergo co-mineralization.

[0246] Application Example 2

[0247] Example 1 was repeated, except that in the incineration process of step 2), the iron content w of the high-volatile organic hazardous waste entering the rotary kiln C1 was detected by the material iron content detection device 13 to be 53%. Based on the detected material iron content, the combustion temperature T0 required to be controlled in the incineration chamber 20202 was determined to be 620°C.

[0248] The temperature detection device 12 detects the real-time combustion temperature T in the incineration chamber 20202 as 540°C. Obviously, T < T0, indicating that the temperature in the incineration chamber 20202 needs to be increased. At this time, the gas analyzer 14 detects the real-time oxygen content and the real-time combustible component content in the flue gas after incineration.

[0249] The gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 8%, and the real-time combustible component content is 1%, that is, the real-time oxygen content and combustible component content are normal. At this time, the heat supplement burner 303 is turned on to supplement the heat supply in the rotary kiln C1, so that T=T0.

[0250] Since T0 = 620°C, the cold slag obtained in step 4) is a high-carbon residue. Therefore, the sintering process described in step 5) is as follows: the high-carbon residue obtained in step 4) is placed in the upper distribution mechanism 803 on the sintering machine C2, which distributes the sintering raw material onto the sintering trolley. The upper distribution mechanism 803 then distributes the high-carbon residue above the sintering raw material for ignition and sintering. Distributing the high-carbon residue to the upper layer of the sintering material increases the heat in the upper layer and improves the ignition effect.

[0251] Application Example 3

[0252] Example 2 is repeated, except that the gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 4%, that is, the real-time oxygen content is low. At this time, the air flow rate into the rotary kiln C1 is increased, and the feed rate into the rotary kiln C1 is increased at the same time, thereby increasing the oxygen content in the rotary kiln C1 and making T=T0.

[0253] Application Example 4

[0254] Example 2 is repeatedly applied, except that the gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 12% and the real-time combustible component content is 2%, that is, the real-time oxygen content is high and the real-time combustible component content is normal. At this time, the air intake into the rotary kiln C1 is reduced, thereby reducing the oxygen content in the rotary kiln C1 and making T=T0.

[0255] Application Example 5

[0256] Example 4 is repeated, except that the gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal. At this time, the feed amount in the rotary kiln C1 is increased, so that the oxygen content in the rotary kiln C1 is reduced by incineration of the material, and T=T0.

[0257] Application Example 6

[0258] Example 1 was repeated, except that in the incineration process of step 2), the iron content w = 3% of the high-volatile organic hazardous waste entering the rotary kiln C1 was detected by the material iron content detection device 13. Based on the detected material iron content, the combustion temperature T0 = 890° C. to be controlled in the incineration chamber 20202 was determined.

[0259] The temperature detection device 12 detects the real-time combustion temperature T in the incineration chamber 20202 as 967°C. Clearly, T>T0, indicating that the temperature in the incineration chamber 20202 needs to be lowered. The gas analyzer 14 then detects the real-time oxygen content and combustible component content in the flue gas after incineration.

[0260] The gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 7%, and the real-time combustible component content is 2.5%, that is, the real-time oxygen content and combustible component content are normal. At this time, the heat supply of the heat supply burner 303 is reduced so that T=T0.

[0261] Since T0 = 890°C, the cold slag obtained in step 4) is carbon-free at this time. Therefore, the sintering process described in step 5) is specifically as follows: the carbon-free residue obtained in step 4) is placed into the lower-layer distribution machine 801 on the sintering machine C2. The lower-layer distribution machine 801 distributes the carbon-free residue as a base material to the sintering trolley. The sintering raw material is then distributed above the base material and ignited for sintering. The carbon-free residue is distributed to the lower layer of the sintering material, acting as a base material, which effectively reduces the heat in the lower sintering layer and protects the sintering trolley grate.

[0262] Application Example 7

[0263] Example 6 is repeated, except that the gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 3%, that is, the real-time oxygen content is low. At this time, the air flow rate into the rotary kiln C1 is increased, and the feed rate into the rotary kiln C1 is reduced at the same time, thereby increasing the oxygen content in the rotary kiln C1 and making T=T0.

[0264] Application Example 8

[0265] Example 6 is repeatedly applied, except that the gas analyzer 14 detects that the real-time oxygen content in the flue gas after incineration is 11% and the real-time combustible component content is 1.5%, that is, the real-time oxygen content is high and the real-time combustible component content is normal. At this time, the air intake into the rotary kiln C1 is reduced, and the feed amount into the rotary kiln C1 is reduced at the same time, thereby reducing the oxygen content in the rotary kiln C1 and making T=T0.

Claims

1. A system for co-disposal of organic hazardous waste by temperature-controlled oxygen-controlled combustion, the system comprising a rotary kiln (C1); the rotary kiln (C1) comprising a kiln head (1), a kiln body (2) and a kiln tail (3); a material inlet (101) is provided on the kiln head (1); the kiln body (2) comprises a furnace lining (201) and a furnace (202); a material outlet (301) and a kiln tail air duct (302) are provided on the kiln tail (3); along the direction of the material, the furnace (202) is divided into a pyrolysis chamber (20201) and an incineration chamber (20202); a kiln air duct (4) is provided inside the furnace lining (201) corresponding to the pyrolysis chamber (20201); one end of the kiln air duct (4) extends outward from the kiln tail The kiln head (1) is connected to the combustion chamber (20202); the kiln head (1) is also provided with an annular air duct (5); the kiln air duct (4) is connected to the primary air duct (6) arranged outside the rotary kiln (C1) through the annular air duct (5); a secondary air duct (7) is branched from the primary air duct (6); the secondary air duct (7) passes through the kiln head (1) and is connected to the pyrolysis chamber (20201); n kiln air ducts (4) are provided in the rotary kiln (C1); the n kiln air ducts (4) are evenly distributed along the circumference of the rotary kiln (C1); each kiln air duct (4) is connected to the annular air duct (5) arranged at the kiln head (1); wherein: n is 2-30.

2. The system according to claim 1, wherein: The system further comprises a sintering machine (C2) arranged downstream of the rotary kiln (C1); a lower-layer material distributor (801), a middle-layer material distributor (802), and an upper-layer material distributor (803) are sequentially arranged above a sintering trolley located in a feeding section of the sintering machine (C2) along the direction of the material; and a material outlet (301) of the rotary kiln (C1) is connected to the lower-layer material distributor (801), the middle-layer material distributor (802), or the upper-layer material distributor (803).

3. The system according to claim 2, characterized in that: The system further comprises a hot slag cooler (9) arranged between the rotary kiln (C1) and the sintering machine (C2); the hot slag cooler (9) is provided with a hot slag inlet (901), a cold slag outlet (902), a cold medium inlet (903) and a hot medium outlet (904); the material outlet (301) of the rotary kiln (C1) is connected to the hot slag inlet (901) of the hot slag cooler (9); and the cold slag outlet (902) of the hot slag cooler (9) is connected to a lower-layer material distributor (801), a middle-layer material distributor (802) or an upper-layer material distributor (803) on the sintering machine (C2).

4. The system according to claim 3, wherein: The hot slag cooler (9) is a dry hot slag cooler.

5. The system according to claim 4, characterized in that: The hot slag cooler (9) is a partition-type heat exchanger.

6. The system according to any one of claims 1 to 5, characterized in that: n is 3-20; and / or A three-way valve (10) is provided at the position where the secondary air duct (7) is separated from the primary air duct (6); an air extraction device (11) is provided on the secondary air duct (7); and / or A temperature detection device (12) is provided in the combustion chamber (20202) of the rotary kiln (C1); a material iron content detection device (13) is provided at the material inlet (101) of the kiln head (1); and a gas analyzer (14) is provided on the primary air duct (6) near the annular air duct (5).

7. The system according to claim 6, characterized in that: A supplementary heat burner (303) is also provided on the kiln tail (3) of the rotary kiln (C1).

8. A method of using the system according to any one of claims 1 to 7, the method comprising the following steps: 1) Pyrolysis: High-volatile organic hazardous waste is transported to the rotary kiln (C1) through the material inlet (101) of the kiln head (1); combustion air enters the rotary kiln (C1) through the kiln tail air duct (302); the high-volatile organic hazardous waste first enters the pyrolysis chamber (2201) of the rotary kiln (C1) for drying and pyrolysis; after the pyrolysis is completed, the material residue and pyrolysis gas enter the incineration chamber (2202); 2) Incineration: Material residue, pyrolysis gas and combustion-supporting air are mixed and burned in the incineration chamber (20202); after the incineration, the hot slag is discharged from the rotary kiln (C1) through the material outlet (301) at the kiln tail (3); the smoke after incineration is discharged from the rotary kiln (C1) through the kiln air duct (4), the annular air duct (5) and the primary air duct (6); 3) Flue gas circulation: Part of the flue gas that enters the primary air duct (6) in step 2) enters the rotary kiln (C1) again through the secondary air duct (7) and completes the pyrolysis and incineration process together with the materials in the rotary kiln (C1).

9. The method according to claim 8, characterized in that: The high-volatile organic hazardous waste is an organic hazardous waste with a mass percentage of volatile matter on a dry basis greater than or equal to H%, wherein H is 6-12.

10. The method according to claim 9, characterized in that: H is 7-10.

11. The method according to claim 8, wherein: The method further includes: 4) Cooling: The hot slag discharged from the rotary kiln (C1) in step 2) is transported to a hot slag cooler (9), and a cooling medium is introduced into the hot slag cooler (9); the hot slag and the cooling medium perform heat exchange in the hot slag cooler (9), and after the heat exchange is completed, cold slag and a hot medium are obtained; 5) Sintering: Place the cold slag obtained in step 4) and the sintering raw materials on a sintering trolley and ignite and sinter.

12. The method according to claim 11, wherein: In step 4), the cooling medium introduced into the hot slag cooler (9) is cold air; the cold air is converted into hot air through heat exchange in the hot slag cooler (9) and then discharged from the hot medium outlet (904), and the hot air is transported as combustion-supporting air to the kiln tail air duct (302) of the rotary kiln (C1); or In step 4), the cooling medium introduced into the hot slag cooler (9) is cooling water; the cooling water is converted into hot water through heat exchange in the hot slag cooler (9) and then discharged from the heat medium outlet (904), and the hot water is used as boiler feed water.

13. The method according to any one of claims 8 to 12, characterized in that: In step 2), the iron content w of the high-volatile organic hazardous waste entering the rotary kiln (C1) is detected by the material iron content detection device (13); the combustion temperature T0 required to be controlled in the incineration chamber (2202) is determined based on the detected material iron content; specifically: When w>50%, T0 is 550~650℃; When 25%<w≤50%, T0 is 650~750℃; When 5%≤w≤25%, T0 is 750~850℃; When w<5%, T0 is 850~950℃; and / or In step 1), the pyrolysis temperature in the pyrolysis chamber (20201) of the rotary kiln (C1) is 200-550°C.

14. The method according to claim 13, wherein: The pyrolysis temperature in the pyrolysis chamber (20201) of the rotary kiln (C1) is 300-500°C.

15. The method according to claim 14, characterized in that: According to the combustion temperature T0 to be controlled in the incineration chamber (2202) in step 2), the type of cold slag obtained in step 4) is determined; specifically: When T0 is 550-650°C, the cold slag obtained in step 4) is a high-carbon residue; When T0 is 650-850°C, the cold slag obtained in step 4) is a low-carbon residue; When T0 is 850-950°C, the cold slag obtained in step 4) is a carbon-free residue.

16. The method according to claim 15, characterized in that: The organic matter content of the high carbon residue is greater than Z%, and the organic matter content of the low carbon residue is less than or equal to Z%, wherein Z is 4-12.

17. The method according to claim 16, wherein: Z is 5-10.

18. The method according to claim 15, wherein: According to the type of cold slag obtained in step 4), step 5) is specifically as follows: When the cold slag obtained in step 4) is a high-carbon residue, the high-carbon residue is placed in the upper distribution machine (803) on the sintering machine (C2), that is, the sintering raw material is distributed to the sintering trolley, and then the high-carbon residue is distributed above the sintering raw material by the upper distribution machine (803), and ignited and sintered; When the cold slag obtained in step 4) is a low-carbon residue, the low-carbon residue is mixed with the sintering raw materials to form a sintering mixture, which is then placed in the middle-layer distribution machine (802) on the sintering machine (C2). The sintering mixture is then distributed to the sintering trolley by the middle-layer distribution machine (802) and ignited for sintering. When the cold slag obtained in step 4) is a carbon-free residue, the carbon-free residue is placed in the lower material distribution machine (801) on the sintering machine (C2), and the carbon-free residue is distributed as a base material to the sintering trolley through the lower material distribution machine (801), and then the sintering raw material is distributed above the base material and ignited for sintering.

19. The method according to claim 13, wherein: In the incineration process of step 2), when the material residue, pyrolysis gas and combustion-supporting air are burned, the temperature changes in the incineration chamber (20202) are monitored in real time, and the oxygen content and combustible component content in the flue gas after incineration are monitored in real time, and then the air intake and / or feed amount and / or the heat supply of the heat supply burner (303) in the rotary kiln (C1) are adjusted, thereby achieving control of the process conditions of the incineration process and controlling the combustion temperature in the incineration chamber (20202).

20. The method according to claim 19, wherein: The process conditions of the incineration process are controlled to control the combustion temperature in the incineration chamber (2202), specifically including the following sub-steps: 201) When the material residue, pyrolysis gas and combustion-supporting air are burning, the temperature detection device (12) monitors the combustion temperature in the incineration chamber (2202) in real time; during the real-time monitoring process, the detected real-time combustion temperature T in the incineration chamber (2202) is compared with the combustion temperature T0 required to be controlled in the incineration chamber (2202); 201a) If the real-time combustion temperature T in the incineration chamber (2202) = the combustion temperature T0 to be controlled, that is, the incineration process is operating normally at this time, the temperature detection device (12) continues to monitor; 201b) If the real-time combustion temperature T in the incineration chamber (2202) is less than the combustion temperature T0 to be controlled, the temperature in the incineration chamber (2202) needs to be increased; at this time, the real-time oxygen content and the real-time combustible component content in the flue gas after incineration are detected by the gas analyzer (14); If it is detected that the real-time oxygen content and combustible component content in the flue gas after incineration are normal, the supplementary heat burner (303) is turned on, or the feed amount in the rotary kiln (C1) is increased, and the air flow in the rotary kiln (C1) is increased at the same time, so that T=T0; If the real-time oxygen content in the flue gas after incineration is detected to be low, the air flow rate in the rotary kiln (C1) is increased, and the feed rate in the rotary kiln (C1) is increased at the same time, or the supplementary heat burner (303) is turned on, so that T=T0; If it is detected that the real-time oxygen content in the flue gas after incineration is high and the real-time combustible component content is normal, the air flow rate in the rotary kiln (C1) is reduced, or the feed rate in the rotary kiln (C1) is increased, or the supplementary heat burner (303) is turned on, so that T=T0; 201c) If the real-time combustion temperature T in the incineration chamber (2202) is greater than the desired combustion temperature T0, the temperature in the incineration chamber (2202) needs to be lowered; at this time, the real-time oxygen content and the real-time combustible component content in the flue gas after incineration are detected by a gas analyzer (14); If it is detected that the real-time oxygen content and combustible component content in the flue gas after incineration are normal, the heat supply of the heat supply burner (303) is reduced, or the feed amount in the rotary kiln (C1) is reduced, and the air supply in the rotary kiln (C1) is reduced at the same time, so that T=T0; If it is detected that the real-time oxygen content in the flue gas after incineration is low, the air flow rate in the rotary kiln (C1) is increased, while the feed rate in the rotary kiln (C1) is reduced, or the heat supply of the heat supply burner (303) is reduced, so that T=T0; If it is detected that the real-time oxygen content in the flue gas after incineration is too high and the real-time combustible component content is normal, the air flow into the rotary kiln (C1) is reduced, the feed amount into the rotary kiln (C1) is reduced, or the heat supply of the heat supply burner (303) is reduced, so that T=T0.

21. A method of using the system according to any one of claims 1 to 7, the method comprising the steps of: a) Low-volatile organic hazardous waste is transported to the rotary kiln (C1) through the material inlet (101) of the kiln head (1); combustion-supporting air enters the rotary kiln (C1) through the secondary air duct (7) of the kiln head (1); the low-volatile organic hazardous waste and the combustion-supporting air are mixed and burned in the furnace (202); b) After the incineration is completed, the hot slag is discharged from the rotary kiln (C1) through the material outlet (301) at the kiln tail (3); the smoke after the incineration is discharged from the rotary kiln (C1) through the kiln tail air duct (302); c) transporting the hot slag discharged from the rotary kiln (C1) in step b) to a hot slag cooler (9), and introducing a cooling medium into the hot slag cooler (9); the hot slag and the cooling medium perform heat exchange in the hot slag cooler (9), and after the heat exchange is completed, cold slag and a hot medium are obtained; d) placing the cold slag obtained in step c) and the sintering raw materials on a sintering trolley and igniting and sintering.

22. The method according to claim 21, characterized in that: The low-volatile organic hazardous waste is an organic hazardous waste with a mass percentage of volatile matter on a dry basis of less than H%, wherein H is 6-12.

23. The method according to claim 22, wherein: H is 7-10.

24. The method according to any one of claims 21 to 23, characterized in that: In step a), the combustion-supporting air also enters the combustion chamber (20202) of the rotary kiln (C1) through the primary air duct (6), the annular air duct (5), and the kiln air duct (4).

25. The method according to claim 24, wherein: The amount of the combustion-supporting air entering the rotary kiln (C1) through the secondary air duct (7) accounts for 20% to 45% of the total air amount required in the rotary kiln (C1).

26. The method according to claim 25, characterized in that: The amount of the combustion-supporting air entering the rotary kiln (C1) through the secondary air duct (7) accounts for 30% to 40% of the total air amount required in the rotary kiln (C1).

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