Microwave pyrolysis sludge drying system and device

Abstract

The invention discloses a microwave pyrolysis sludge drying system and device, which comprises: a sludge pretreatment unit, which receives and stores wet sludge, performs preliminary dehydration treatment on the wet sludge to reduce the water content to 60%-65%, and then sends the dehydrated sludge into a microwave heater through a conveying mechanism; the microwave heater is used for uniformly heating the sludge by using microwaves, so that moisture is quickly evaporated, the heating temperature is 100-150 DEG C, and the moisture is effectively removed. The microwave pyrolysis sludge drying system has the advantage of being good in treatment effect, and the problems that in the using process of an existing microwave pyrolysis sludge drying system, the evaporation effect on water in sludge is poor, in order to evaporate redundant water, the system needs to consume more electric energy or heat energy, and the operation cost is remarkably increased are solved.

Description

Technical Field

[0001] The invention relates to the technical field of sludge treatment, and in particular to a microwave pyrolysis sludge drying system and device. Background Art

[0002] Microwave pyrolysis sludge drying system is an environmentally friendly technology that uses microwave heating technology to dry and pyrolyze sludge. This system is mainly used in the treatment of sludge generated by sewage treatment plants to reduce the volume of sludge, increase its calorific value, and realize resource utilization. Microwaves can penetrate materials, causing the water molecules inside the materials to vibrate and generate heat, thereby achieving the effect of rapid heating. Compared with traditional heating methods, microwave heating has the advantages of uniform heating and fast speed. Under certain temperature conditions, the organic matter in the sludge will decompose and produce combustible gas, oil substances and solid carbon. These products can be recycled as energy, which helps to reduce processing costs and reduce environmental pollution.

[0003] During use, the existing microwave pyrolysis sludge drying system has a poor evaporation effect on the water in the sludge. In order to evaporate the excess water, the system needs to consume more electricity or heat energy, which significantly increases the operating cost. Summary of the invention

[0004] The purpose of the present invention is to provide a microwave pyrolysis sludge drying system and device, which has the advantage of good treatment effect and solves the problem that the existing microwave pyrolysis sludge drying system has poor evaporation effect on water in the sludge during use. In order to evaporate excess water, the system needs to consume more electricity or heat energy, which significantly increases the operating cost.

[0005] To achieve the above object, the present invention provides the following technical solution: a microwave pyrolysis sludge drying system, comprising:

[0006] A sludge pretreatment unit receives and stores wet sludge, performs preliminary dehydration treatment on the wet sludge to reduce the water content to 60%-65%, and then delivers the dehydrated sludge to the microwave heater through a conveying mechanism;

[0007] A microwave heater uses microwaves to uniformly heat the sludge to evaporate the water rapidly. The heating temperature is between 100°C and 150°C to ensure effective removal of water.

[0008] A pyrolysis reactor, wherein the pyrolysis reactor performs high-temperature pyrolysis on the microwave-dried sludge at a temperature of 300° C. to 600° C. During the pyrolysis process, organic matter in the sludge is decomposed into combustible gas, oily substances and solid charcoal;

[0009] A gas collection and purification system, wherein the gas collection and purification system collects the combustible gas generated during the pyrolysis process, monitors and controls the content of the combustible gas to be within the range of the explosion threshold, and then processes the combustible gas. The processed combustible gas is used as a heat source for the pyrolysis reactor. The gas collection and purification system collects the tail gas generated by the pyrolysis reactor, purifies the tail gas, and prevents the tail gas from polluting the environment;

[0010] A solid product processing unit, wherein the solid product processing unit cools the solid carbon after pyrolysis, and then screens and packages the cooled solid carbon;

[0011] A control and monitoring system detects the temperature of the microwave heater and the pyrolysis reactor during operation and adjusts the operating temperature according to a preset temperature.

[0012] As a preferred microwave pyrolysis sludge drying system of the present invention, the sludge pretreatment unit includes a sludge receiving and storage unit, a dehydration unit and a conveying unit. The sludge receiving and storage unit includes a receiving tank for storing wet sludge. A stirring structure is installed inside the receiving tank to stir the wet sludge to prevent the wet sludge from agglomerating and settling. The dehydration unit includes a centrifugal dehydrator. The centrifugal dehydrator separates water from the sludge through a high-speed rotating centrifugal drum inside the centrifugal dehydrator. The conveying unit includes a screw conveyor. The screw conveyor pushes and conveys the sludge through a screw rod inside the screw conveyor.

[0013] As a preferred microwave pyrolysis sludge drying system of the present invention, during the operation of the pyrolysis reactor, the inside of the reactor is heated to 300°C-600°C by an electric heating element, and the generated combustible gas and oil substances enter the condenser through the gas outlet, the oil substances are condensed and separated, the combustible gas is collected and stored, the solid charcoal after pyrolysis is discharged through the discharge port for further processing, and the collected gas enters the gas collection and purification system.

[0014] As a preferred microwave pyrolysis sludge drying system of the present invention, the gas collection and purification system includes a gas collection unit and a gas purification unit, the gas collection unit includes a gas outlet, a gas pipeline and a gas flow meter, the gas outlet is installed at the gas outlet end of the pyrolysis reactor, the gas discharged from the pyrolysis reactor enters the gas purification unit through the gas pipeline and the gas flow meter, the gas pipeline transports the gas, and the gas flow meter detects the flow of the gas.

[0015] As a preferred microwave pyrolysis sludge drying system of the present invention, the gas purification unit includes an indirect contact condenser, a cyclone separator, a spray absorption tower and a gas storage tank. The high-temperature gas enters the pipeline inside the indirect contact condenser and indirectly contacts the cooling water to avoid direct mixing of the gas and water to condense the gas. The cyclone separator uses centrifugal force to separate larger particles. The spray absorption tower uses an alkaline solution to absorb sulfur dioxide in the gas. The gas compressor compresses the treated gas and then stores it in the gas storage tank.

[0016] As a preferred microwave pyrolysis sludge drying system of the present invention, the solid product processing unit includes a cooling system and a screening system, the cooling system includes a cooling bed and a cooling fan, the solid carbon is placed on the cooling bed to ensure uniform cooling, the cooling fan provides forced convection cooling air to accelerate the cooling process, the screening system includes a vibrating screen, the feed port of the vibrating screen is connected to the discharge port of the cooling bed, the cooled solid carbon is fed into the vibrating screen, the vibration motor drives the screen on the vibrating screen to vibrate, the screen divides the solid carbon into grades of different particle sizes, and the discharge port on the vibrating screen discharges the screened solid carbon.

[0017] As a preferred microwave pyrolysis sludge drying system of the present invention, the control and monitoring system includes a temperature sensor, a pressure sensor, a flow sensor, a humidity sensor and a PLC controller. The temperature sensor detects the temperature of microwave heating and pyrolysis reaction, the flow sensor detects the flow of gas and liquid, the humidity sensor detects the humidity of the sludge, and the PLC controller receives the detection signal from the sensor and then controls the microwave heater and the pyrolysis reactor.

[0018] A microwave pyrolysis sludge drying system device comprises a microwave heating mechanism, the top of which is connected to a dehumidification mechanism.

[0019] As a preferred microwave pyrolysis sludge drying device of the present invention, the microwave heating mechanism includes a microwave heater body, a microwave generator and a waveguide structure are installed inside the microwave heater body, the top of the microwave heater body is respectively connected to a mud inlet and a dehumidification port, a stirring motor is fixedly connected at the center of the top of the microwave heater body, the output shaft of the stirring motor passes through the inner cavity of the microwave heater body and is installed with a stirring structure, the bottom of the microwave heater body is connected to a lower mud valve, a fixing ring is fixedly connected to the surface of the microwave heater body, a plurality of conveying augers are fixedly installed on the fixing ring, the feed end of the conveying augers passes through the bottom of the inner cavity of the microwave heater body, the discharge end of the conveying augers passes through the top of the inner cavity of the microwave heater body, and the bottom of the microwave heater body is fixedly connected to a base.

[0020] As a preferred microwave pyrolysis sludge drying device of the present invention, the dehumidification mechanism includes a condenser, the top of the condenser is connected to a bent pipe, the bent pipe is connected to the dehumidification port, the bottom of the condenser is connected to a three-way pipe, the water outlet end of the three-way pipe is connected to a water outlet valve, the air outlet end of the three-way pipe is connected to a first multi-head pipe, the air outlet end of the first multi-head pipe is connected to a first solenoid valve, the air outlet end of the first solenoid valve is connected to an activated carbon purifier, the surface fixed sleeve of the activated carbon purifier is provided with a fixed frame, the air outlet end of the activated carbon purifier is connected to a second solenoid valve, the air outlet end of the second solenoid valve is connected to a second multi-head pipe, and the air outlet end of the second multi-head pipe is connected to a fan.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention can quickly reduce the moisture content of wet sludge to 60%-65% through the centrifugal dehydrator in the sludge pretreatment unit, greatly reducing the burden of subsequent treatment. The microwave heater uses microwave technology to evenly heat the sludge, so that the water evaporates quickly and improves the drying efficiency. The pyrolysis reactor pyrolyzes the dried sludge at a high temperature of 300°C-600°C, effectively decomposing organic matter to generate combustible gas, oil substances and solid charcoal.

[0023] 2. The present invention generates combustible gas and oil substances through pyrolysis, which can be used as fuel to achieve energy recovery and utilization. The solid charcoal after pyrolysis can be used for soil improvement, adsorption material or as fuel after cooling and screening, thus realizing waste resource utilization.

[0024] 3. The present invention uses a gas collection and purification system to effectively treat harmful gases generated during the pyrolysis process to ensure that emissions meet environmental standards. The solid carbon processing and packaging process reduces the amount of sludge landfill and reduces the risk of secondary pollution. The efficient dehydration and pyrolysis process reduces energy consumption and reduces operating costs. The economic benefits of the system are increased by recycling combustible gases and oil substances and reusing solid carbon.

[0025] 4. The present invention monitors parameters such as temperature, pressure and flow in real time through the control and monitoring system to ensure the safety of system operation. The PLC controller realizes automatic control of the system, reduces errors caused by human operation, and improves the reliability and stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the system of the present invention;

[0027] Figure 2 It is a schematic diagram of the structure of the microwave pyrolysis sludge drying device of the present invention;

[0028] Figure 3The microwave heating mechanism structure of the present invention is shown in FIG. Figure 1 ;

[0029] Figure 4 The microwave heating mechanism structure of the present invention is shown in FIG. Figure 2 ;

[0030] Figure 5 It is a schematic diagram of the structure of the dehumidification mechanism of the present invention.

[0031] In the figure: 1. microwave heating mechanism; 101. microwave heater body; 102. fixing ring; 103. mud inlet; 104. stirring motor; 105. dehumidification port; 106. conveying auger; 107. lower mud valve; 108. base; 2. dehumidification mechanism; 201. condenser; 202. elbow; 203. three-way pipe; 204. water outlet valve; 205. fixing frame; 206. fan; 207. second manifold; 208. second solenoid valve; 209. activated carbon purifier; 210. first solenoid valve; 211. first manifold. DETAILED DESCRIPTION

[0032] Example 1

[0033] See also Figure 1 , a microwave pyrolysis sludge drying system, comprising:

[0034] The sludge pretreatment unit receives and stores wet sludge, and performs preliminary dehydration treatment on the wet sludge to reduce the water content to 60%-65%, and then delivers the dehydrated sludge to the microwave heater through a conveying mechanism;

[0035] Microwave heater: The microwave heater uses microwaves to evenly heat the sludge to evaporate the water quickly. The heating temperature is 100℃-150℃ to ensure effective removal of water.

[0036] Pyrolysis reactor: The pyrolysis reactor performs high-temperature pyrolysis on the microwave-dried sludge at a temperature of 300°C-600°C. During the pyrolysis process, the organic matter in the sludge is decomposed into combustible gas, oil substances and solid carbon;

[0037] A gas collection and purification system, wherein the gas collection and purification system collects the combustible gas generated during the pyrolysis process, monitors and controls the content of the combustible gas to be within the range of the explosion threshold, and then processes the combustible gas. The processed combustible gas is used as a heat source for the pyrolysis reactor. The gas collection and purification system collects the tail gas generated by the pyrolysis reactor, purifies the tail gas, and prevents the tail gas from polluting the environment;

[0038] A solid product processing unit, wherein the solid product processing unit cools the solid carbon after pyrolysis, and then screens and packages the cooled solid carbon;

[0039] The control and monitoring system detects the temperature of the microwave heater and the pyrolysis reactor during operation and adjusts the operating temperature according to the preset temperature.

[0040] Furthermore, the sludge pretreatment unit includes a sludge receiving and storage unit, a dehydration unit and a conveying unit. The sludge receiving and storage unit includes a receiving tank for storing wet sludge. A stirring structure is installed inside the receiving tank to stir the wet sludge to prevent the wet sludge from agglomerating and settling. The dehydration unit includes a centrifugal dehydrator. The centrifugal dehydrator separates water from the sludge through a high-speed rotating centrifugal drum inside the centrifugal dehydrator. The conveying unit includes a screw conveyor. The screw conveyor pushes and conveys the sludge through a screw rod inside the screw conveyor.

[0041] Furthermore, during the operation of the pyrolysis reactor, the interior of the reactor is heated to 300°C-600°C by an electric heating element, and the generated combustible gas and oil substances enter the condenser through the gas outlet, the oil substances are condensed and separated, the combustible gas is collected and stored, and the solid charcoal after pyrolysis is discharged through the discharge port for further processing, and the collected gas enters the gas collection and purification system.

[0042] Furthermore, the gas collection and purification system includes a gas collection unit and a gas purification unit. The gas collection unit includes a gas outlet, a gas pipeline and a gas flow meter. The gas outlet is installed at the gas outlet end of the pyrolysis reactor. The gas discharged from the pyrolysis reactor enters the gas purification unit through the gas pipeline and the gas flow meter. The gas pipeline transports the gas, and the gas flow meter detects the flow of the gas.

[0043] Furthermore, the gas purification unit includes an indirect contact condenser, a cyclone separator, a spray absorption tower and a gas storage tank. The high-temperature gas enters the pipe inside the indirect contact condenser and indirectly contacts the cooling water to avoid direct mixing of the gas and water to condense the gas. The cyclone separator uses centrifugal force to separate larger particles. The spray absorption tower uses an alkaline solution to absorb sulfur dioxide in the gas. The gas compressor compresses the treated gas and then stores it in a gas storage tank.

[0044] Furthermore, the solid product processing unit includes a cooling system and a screening system. The cooling system includes a cooling bed and a cooling fan. The solid carbon is placed on the cooling bed to ensure uniform cooling. The cooling fan provides forced convection cooling air to accelerate the cooling process. The screening system includes a vibrating screen. The feed port of the vibrating screen is connected to the discharge port of the cooling bed. The cooled solid carbon is fed into the vibrating screen. The vibration motor drives the screen on the vibrating screen to vibrate. The screen divides the solid carbon into grades of different particle sizes. The discharge port on the vibrating screen discharges the screened solid carbon.

[0045] Furthermore, the control and monitoring system includes a temperature sensor, a pressure sensor, a flow sensor, a humidity sensor and a PLC controller. The temperature sensor detects the temperature of microwave heating and pyrolysis reaction, the flow sensor detects the flow of gas and liquid, the humidity sensor detects the humidity of sludge, and the PLC controller receives the detection signal from the sensor and then controls the microwave heater and pyrolysis reactor.

[0046] The centrifugal dehydrator in the sludge pretreatment unit can quickly reduce the moisture content of the wet sludge to 60%-65%, greatly reducing the burden of subsequent treatment. The microwave heater uses microwave technology to evenly heat the sludge, so that the water evaporates quickly and improves the drying efficiency. The pyrolysis reactor pyrolyzes the dried sludge at a high temperature of 300℃-600℃, effectively decomposing organic matter and generating combustible gas, oil substances and solid charcoal.

[0047] The combustible gases and oils produced during the pyrolysis process can be used as fuel to achieve energy recovery and utilization. The solid charcoal after pyrolysis can be used for soil improvement, adsorption materials or as fuel after cooling and screening, thus realizing waste resource utilization.

[0048] The harmful gases generated during the pyrolysis process are effectively treated through the gas collection and purification system to ensure that emissions meet environmental standards. The solid carbon processing and packaging process reduces the amount of sludge landfill and reduces the risk of secondary pollution. The efficient dehydration and pyrolysis process reduces energy consumption and reduces operating costs. The economic benefits of the system are increased by recycling combustible gases and oils and reusing solid carbon.

[0049] The control and monitoring system monitors parameters such as temperature, pressure and flow in real time to ensure the safety of system operation. The PLC controller realizes automatic control of the system, reduces errors caused by human operation, and improves the reliability and stability of the system.

[0050] The system can record historical data of key parameters to facilitate subsequent data analysis and process optimization. Through data analysis, problems in system operation can be discovered in a timely manner, and fault diagnosis and preventive maintenance can be performed. Through continuous processing, the overall processing efficiency and production capacity are improved.

[0051] The microwave pyrolysis sludge drying system achieves effective treatment and resource utilization of sludge through multiple links such as efficient dehydration, uniform heating, high-temperature pyrolysis, gas purification and solid carbon treatment. The system not only improves the treatment efficiency and economic benefits, but also significantly reduces the risk of environmental pollution, and has good environmental performance and safety.

[0052] Example 2

[0053] See also Figure 2-Figure 5A microwave pyrolysis sludge drying device comprises a microwave heating mechanism 1, and a dehumidification mechanism 2 is connected to the top of the microwave heating mechanism 1.

[0054] Furthermore, the microwave heating mechanism 1 includes a microwave heater body 101, a microwave generator and a waveguide structure are installed inside the microwave heater body 101, a mud inlet 103 and a dehumidification port 105 are respectively connected to the top of the microwave heater body 101, a stirring motor 104 is fixedly connected at the center of the top of the microwave heater body 101, the output shaft of the stirring motor 104 passes through the inner cavity of the microwave heater body 101 and is installed with a stirring structure, a lower mud valve 107 is connected to the bottom of the microwave heater body 101, a fixing ring 102 is fixedly connected to the surface of the microwave heater body 101, a plurality of conveying screw dragons 106 are fixedly installed on the fixing ring 102, a feeding end of the conveying screw dragon 106 passes through the bottom of the inner cavity of the microwave heater body 101, a discharging end of the conveying screw dragon 106 passes through the top of the inner cavity of the microwave heater body 101, and a base 108 is fixedly connected to the bottom of the microwave heater body 101.

[0055] Furthermore, the dehumidification mechanism 2 includes a condenser 201, a bend pipe 202 is connected to the top of the condenser 201, the bend pipe 202 is connected to the dehumidification port 105, the bottom of the condenser 201 is connected to a three-way pipe 203, the water outlet end of the three-way pipe 203 is connected to a water outlet valve 204, the air outlet end of the three-way pipe 203 is connected to a first multi-head pipe 211, the air outlet end of the first multi-head pipe 211 is connected to a first solenoid valve 210, the air outlet end of the first solenoid valve 210 is connected to an activated carbon purifier 209, the surface of the activated carbon purifier 209 is fixedly sleeved with a fixing frame 205, the air outlet end of the activated carbon purifier 209 is connected to a second solenoid valve 208, the air outlet end of the second solenoid valve 208 is connected to a second multi-head pipe 207, and the air outlet end of the second multi-head pipe 207 is connected to a fan 206.

[0056] When the sludge is heated and dehydrated, the sludge is poured into the heating chamber inside the microwave heater body 101 through the sludge inlet 103, and the microwave generator and waveguide structure inside the microwave heater body 101 start to work. The microwave generator is a magnetron, which generates microwave energy with a frequency of 2.45 GHz. The waveguide structure transmits the microwave energy from the magnetron to the heating chamber. The waveguide structure ensures efficient transmission of microwave energy and avoids energy loss. The sludge in the heating chamber absorbs microwave energy, and water molecules vibrate rapidly in the microwave field to generate heat, thereby increasing the sludge temperature and evaporating the water.

[0057] When evaporating water from the sludge, the output shaft of the stirring motor 104 drives the stirring structure to rotate inside the heating chamber to evenly mix the sludge and ensure uniform distribution of microwave energy. At the same time, the conveying auger 106 returns the sludge at the bottom of the inner cavity of the microwave heater body 101 to the top of the inner cavity of the microwave heater body 101, so that the sludge always remains in a flowing state, thereby improving the evaporation efficiency. When the evaporation is completed, the lower mud valve 107 is opened to discharge the sludge.

[0058] In the process of evaporating water, the dehumidification mechanism 2 extracts moisture from the inner cavity of the microwave heater body 101 through the dehumidification port 105 to prevent the sludge from returning to moisture. During the operation of the dehumidification mechanism 2, the fan 206 extracts moisture through the activated carbon purifier 209 and the condenser 201, and the moisture enters the interior of the condenser 201 through the elbow 202. The condenser 201 is connected to the cooling water of the external circulation, and the cooling water condenses the high-temperature moisture inside the elbow 202 through the condenser 201. The waste water generated by the condensation is automatically discharged into the waste water treatment equipment through the three-way pipe 203 and the outlet valve 204. The condensed waste gas passes through the three-way pipe 20 3. The first manifold 211 and the first solenoid valve 210 enter into a plurality of activated carbon purifiers 209. An activated carbon adsorbent is arranged inside the activated carbon purifier 209. The activated carbon adsorbent adsorbs organic matter and impurities in the exhaust gas. The purified exhaust gas enters the fan 206 through the second solenoid valve 208 and the second manifold 207, and is discharged through the fan 206. When the activated carbon adsorbent needs to be replaced, the single first solenoid valve 210 and the second solenoid valve 208 are closed, and the activated carbon purifier 209 is disassembled for maintenance, while the other activated carbon purifiers 209 continue to work, so that maintenance without stopping the machine is realized.

[0059] The magnetron inside the microwave heater body 101 generates 2.45 GHz microwave energy, which is efficiently transmitted to the heating chamber through the waveguide structure. The microwave energy directly acts on the water molecules in the sludge, causing them to vibrate rapidly and generate heat, thereby achieving uniform heating and improving the efficiency of water evaporation. The stirring motor 104 drives the stirring structure to rotate in the heating chamber to ensure uniform mixing of the sludge, so that the microwave energy can be evenly distributed, further improving the efficiency of water evaporation. The conveying auger 106 returns the sludge at the bottom of the heating chamber to the top, maintaining the flow state of the sludge and avoiding local overheating or uneven drying, thereby improving the overall evaporation efficiency.

[0060] The dehumidification mechanism 2 extracts moisture in the heating chamber through the dehumidification port 105, effectively preventing the sludge from getting wet and ensuring the drying effect of the sludge. The fan 206 extracts moisture through the activated carbon purifier 209 and the condenser 201. The moisture is condensed into wastewater by cooling water in the condenser 201 and discharged into the wastewater treatment equipment through the three-way pipe 203 and the outlet valve 204. This not only reduces the impact of moisture on the environment, but also recycles part of the water resources.

[0061] The condensed exhaust gas enters the activated carbon purifier 209 through the first solenoid valve 210, and the activated carbon adsorbent adsorbs organic matter and impurities in the exhaust gas. The purified exhaust gas is then discharged through the second solenoid valve 208 and the fan 206. This process significantly reduces the emission of harmful substances and meets environmental protection standards. Multiple activated carbon purifiers 209 work in parallel. When a certain activated carbon purifier 209 needs to be replaced and maintained, the corresponding solenoid valve can be closed, and the purifier can be disassembled and maintained, while other purifiers continue to work, realizing non-stop maintenance and ensuring continuous operation of the system.

[0062] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A microwave pyrolysis sludge drying system, characterized in that: include: A sludge pretreatment unit receives and stores wet sludge, performs preliminary dehydration treatment on the wet sludge to reduce the water content to 60%-65%, and then delivers the dehydrated sludge to the microwave heater through a conveying mechanism; A microwave heater uses microwaves to uniformly heat the sludge to evaporate the water rapidly. The heating temperature is between 100°C and 150°C to ensure effective removal of water. A pyrolysis reactor, wherein the pyrolysis reactor performs high-temperature pyrolysis on the microwave-dried sludge at a temperature of 300° C. to 600° C. During the pyrolysis process, organic matter in the sludge is decomposed into combustible gas, oily substances and solid charcoal; A gas collection and purification system, wherein the gas collection and purification system collects the combustible gas generated during the pyrolysis process, monitors and controls the content of the combustible gas to be within the range of the explosion threshold, and then processes the combustible gas. The processed combustible gas is used as a heat source for the pyrolysis reactor. The gas collection and purification system collects the tail gas generated by the pyrolysis reactor, purifies the tail gas, and prevents the tail gas from polluting the environment; A solid product processing unit, wherein the solid product processing unit cools the solid carbon after pyrolysis, and then screens and packages the cooled solid carbon; A control and monitoring system detects the temperature of the microwave heater and the pyrolysis reactor during operation and adjusts the operating temperature according to a preset temperature.

2. The microwave pyrolysis sludge drying system according to claim 1, characterized in that: The sludge pretreatment unit includes a sludge receiving and storage unit, a dehydration unit and a conveying unit. The sludge receiving and storage unit includes a receiving tank for storing wet sludge. A stirring structure is installed inside the receiving tank to stir the wet sludge to prevent the wet sludge from agglomerating and settling. The dehydration unit includes a centrifugal dehydrator. The centrifugal dehydrator separates water from the sludge through a centrifugal drum rotating at a high speed inside the centrifugal dehydrator. The conveying unit includes a screw conveyor. The screw conveyor pushes and conveys the sludge through a screw rod inside the screw conveyor.

3. The microwave pyrolysis sludge drying system according to claim 2, characterized in that: During the operation of the pyrolysis reactor, the interior of the reactor is heated to 300°C-600°C by an electric heating element, and the generated combustible gas and oil substances enter the condenser through the gas outlet, the oil substances are condensed and separated, the combustible gas is collected and stored, the solid char after pyrolysis is discharged through the discharge port for further processing, and the collected gas enters the gas collection and purification system.

4. The microwave pyrolysis sludge drying system according to claim 3, characterized in that: The gas collection and purification system includes a gas collection unit and a gas purification unit. The gas collection unit includes a gas outlet, a gas pipeline and a gas flow meter. The gas outlet is installed at the gas outlet end of the pyrolysis reactor. The gas discharged from the pyrolysis reactor enters the gas purification unit through the gas pipeline and the gas flow meter. The gas pipeline transports the gas, and the gas flow meter detects the flow of the gas.

5. The microwave pyrolysis sludge drying system according to claim 4, characterized in that: The gas purification unit includes an indirect contact condenser, a cyclone separator, a spray absorption tower and a gas storage tank. The high-temperature gas enters the pipe inside the indirect contact condenser and indirectly contacts the cooling water to avoid direct mixing of the gas and water to condense the gas. The cyclone separator uses centrifugal force to separate larger particles. The spray absorption tower uses an alkaline solution to absorb sulfur dioxide in the gas. The gas compressor compresses the treated gas and then stores it in a gas storage tank.

6. The microwave pyrolysis sludge drying system according to claim 5, characterized in that: The solid product processing unit includes a cooling system and a screening system. The cooling system includes a cooling bed and a cooling fan. The solid carbon is placed on the cooling bed to ensure uniform cooling. The cooling fan provides forced convection cooling air to accelerate the cooling process. The screening system includes a vibrating screen. The feed port of the vibrating screen is connected to the discharge port of the cooling bed. The cooled solid carbon is fed into the vibrating screen. The vibrating motor drives the screen on the vibrating screen to vibrate. The screen divides the solid carbon into grades of different particle sizes. The discharge port on the vibrating screen discharges the screened solid carbon.

7. The microwave pyrolysis sludge drying system according to claim 6, characterized in that: The control and monitoring system includes a temperature sensor, a pressure sensor, a flow sensor, a humidity sensor and a PLC controller. The temperature sensor detects the temperature of microwave heating and pyrolysis reaction, the flow sensor detects the flow of gas and liquid, the humidity sensor detects the humidity of sludge, and the PLC controller receives the detection signal from the sensor and then controls the microwave heater and pyrolysis reactor.

8. A microwave pyrolysis sludge drying device, suitable for the microwave pyrolysis sludge drying system according to claim 7, comprising a microwave heating mechanism (1), characterized in that: The top of the microwave heating mechanism (1) is connected to a dehumidification mechanism (2).

9. The microwave pyrolysis sludge drying device according to claim 8, characterized in that: The microwave heating mechanism (1) comprises a microwave heater body (101), a microwave generator and a waveguide structure are installed inside the microwave heater body (101), a mud inlet (103) and a dehumidification port (105) are respectively connected to the top of the microwave heater body (101), a stirring motor (104) is fixedly connected to the center of the top of the microwave heater body (101), the output shaft of the stirring motor (104) passes through the inner cavity of the microwave heater body (101) and is installed with a stirring structure, and the microwave heater body The bottom of the microwave heater body (101) is connected to a lower mud valve (107); a fixing ring (102) is fixedly connected to the surface of the microwave heater body (101); a plurality of conveying screws (106) are fixedly installed on the fixing ring (102); a feeding end of the conveying screw (106) passes through the bottom of the inner cavity of the microwave heater body (101); a discharging end of the conveying screw (106) passes through the top of the inner cavity of the microwave heater body (101); and a base (108) is fixedly connected to the bottom of the microwave heater body (101).

10. The microwave pyrolysis sludge drying device according to claim 9, characterized in that: The dehumidification mechanism (2) comprises a condenser (201), the top of the condenser (201) is connected to a bent pipe (202), the bent pipe (202) is connected to a dehumidification port (105), the bottom of the condenser (201) is connected to a three-way pipe (203), the water outlet end of the three-way pipe (203) is connected to a water outlet valve (204), the air outlet end of the three-way pipe (203) is connected to a first multi-head pipe (211), and the air outlet end of the first multi-head pipe (211) is connected to A first solenoid valve (210) is provided, wherein the air outlet end of the first solenoid valve (210) is connected to an activated carbon purifier (209), a fixed frame (205) is provided on the surface of the activated carbon purifier (209), the air outlet end of the activated carbon purifier (209) is connected to a second solenoid valve (208), the air outlet end of the second solenoid valve (208) is connected to a second multi-head pipe (207), and the air outlet end of the second multi-head pipe (207) is connected to a fan (206).

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