Industrial waste salt treatment device and method based on circulating medium resistance barrier discharge fluidized bed

Abstract

The application discloses a kind of industrial waste salt processing device and method based on circulating dielectric barrier discharge fluidized bed.The device includes circulating fluidized reactor.Circulating fluidized reactor is equipped with annular structure circulating reaction flow channel.Circulating reaction flow channel is equipped with reaction discharge area, reflux section and feeding area connected in turn into annular shape.The circulating fluidized reactor in the application can make waste salt particles in fluidized state circulating flow, repeatedly enter the reaction discharge area of plasma discharge, so that waste salt particles react with active particles generated by discharge in fully dispersed fluidized state, realize the efficient degradation of organic pollutants.At the same time, the circulating fluidized reactor in the application has the characteristics of continuous sample input, can continuously process waste salt, and ensures the scale and reaction rate of waste salt treatment.The carrier gas input into reaction discharge area from side strengthens the disturbance of fluidized state waste salt particles in reaction discharge area and improves reaction rate.

Description

Technical Field

[0001] This invention belongs to the field of industrial waste salt treatment technology, specifically relating to an industrial waste salt treatment device and method based on a circulating medium-barrier discharge electrochemical bed. Background Technology

[0002] my country's chemical industry is massive, generating large quantities of waste salt during production. This waste salt pollution is characterized by its large volume, complex composition, and significant environmental risks. Currently, approximately 70% of waste salt is disposed of through landfill or open-air dumping, with leachate polluting groundwater. Resource utilization of chemical waste salt is a crucial aspect of achieving hazardous waste reduction and resource recovery. A key challenge in resource utilization lies in the removal of organic impurities.

[0003] Dielectric barrier discharge is a discharge method in which an insulating dielectric is covered on the surface of electrode 10 or inserted into the space. After a voltage is applied to electrode 10, an electric field is formed in the air gap. When the applied electric field strength reaches the breakdown field strength, the gas between electrode 10 is broken down and discharge occurs. The introduction of the dielectric can prevent atmospheric pressure gas discharge from forming an electric arc. At this time, the macroscopic manifestation is light and heat, and the microscopic manifestation is the generation of current and active particles. A large-area uniform discharge plasma can be generated under atmospheric pressure to treat waste salt. During the discharge process, high-energy electrons and active substances react with organic matter to decompose organic matter, deeply remove organic impurities in waste salt, avoid the generation of high salinity and subsequent treatment, and because of the effect of the concentrated electric field, the discharge voltage can be reduced, the energy utilization rate can be improved, and the operating cost can be reduced.

[0004] Circulating fluidized beds allow waste salt to be fluidized and fully reacted. By controlling the reaction time and processing capacity through the number of cycles, the efficiency of industrial waste salt treatment can be improved. The main focus of research and improvement on circulating fluidized bed reactors is to increase the contact area, residence time, and processing capacity of plasma in the discharge reaction zone and industrial waste salt, thus solving several major problems existing in current fixed fluidized bed devices.

[0005] During the treatment process, a fouling layer forms on the inner wall of the equipment due to the deposition of waste salt particles. This may include organic residues or other impurities. The agglomeration or channeling of waste salt particles affects the flow rate of the waste salt, increasing the processing time. It also causes uneven and insufficient contact between the waste salt and the plasma, resulting in fluctuations in TOC removal rate. Waste salt particles agglomerated on the reactor may also cause the wall temperature to exceed the limit. This phenomenon can lead to decreased equipment efficiency, increased energy consumption, and even equipment damage. Summary of the Invention

[0006] The purpose of this invention is to provide an industrial waste salt treatment device and method based on a circulating dielectric barrier discharge electrochemical bed, and to systematically examine the treatment process and products of the device for chemical waste salt as the treatment object, and to form a method with the optimal technical parameters for organic matter removal rate.

[0007] In a first aspect, the present invention provides an industrial waste salt treatment device based on a circulating dielectric barrier discharge electrochemical bed, comprising a circulating fluidized bed reactor. The circulating fluidized bed reactor has an annular circulating reaction channel. The circulating reaction channel has a reaction discharge zone, a reflux section, and a feeding zone connected in sequence in an annular shape. The feeding zone has an outlet, a feed inlet, a first inlet, and an outlet arranged at intervals along the gas circulation direction. A filter screen is provided at the outlet. The carrier gas input through the first inlet causes the waste salt particles input through the outlet to enter a fluidized state and circulate along the circulating reaction channel. Electrodes are provided on both sides of the reaction discharge zone. The circulating reaction channel forms a dielectric barrier layer for plasma discharge on the tube wall of the reaction discharge zone. The reaction discharge zone is equipped with a gas distributor for lateral input of carrier gas. The carrier gas input through the gas distributor disturbs the airflow in the reaction discharge zone, improving the reaction effect and blowing off solid deposits on the inner wall of the reaction discharge zone, alleviating the problem of dirty walls.

[0008] Preferably, the reactive discharge region is equipped with an embedded dielectric sensor. The embedded dielectric sensor is used to detect the dielectric constant within the reactive discharge region.

[0009] Preferably, the industrial waste salt treatment device further includes a blower. The gas distributor includes multiple second air inlets located at different positions on the side of the tube wall in the reaction discharge zone. The first air inlet of the feeding zone and the gas distributor are both connected to the blower.

[0010] Preferably, both the inlet and outlet are equipped with valves.

[0011] Preferably, the dielectric material of the tube wall in the reaction discharge region is microwave ceramic with a dielectric constant of 3 to 5. A CeO2-TiO2 composite catalyst is loaded on the inner wall of the reaction discharge region. During operation, ultraviolet light is applied to the transparent tube wall of the reaction discharge region.

[0012] The industrial waste salt treatment device provided by this invention achieves highly efficient removal of organic matter from industrial waste salt by combining a novel circulating fluidized bed design with dielectric barrier discharge technology using new dielectric materials. Compared with traditional treatment methods, this invention has advantages such as higher treatment efficiency, lower energy consumption, convenient and intelligent operation, and no wall fouling. Through the reaction of high-energy electrons and active substances with organic matter during the discharge process, the organic matter is decomposed, while avoiding the generation of large amounts of wastewater, thus contributing to the resource utilization of industrial waste salt.

[0013] Secondly, the present invention provides a method for treating industrial waste salt, which uses the aforementioned industrial waste salt treatment device. The industrial waste salt treatment method includes: Industrial waste salt is crushed and screened into waste salt particles; the discharge port is closed, and the waste salt particles are fed into the inlet. Carrier gas is introduced into the first inlet and the gas distributor. The flow rate of the carrier gas is greater than the critical fluidization velocity, causing the waste salt particles to circulate in a fluidized state in the circulating reaction channel.

[0014] Power is supplied to the electrodes in the reaction discharge region, causing plasma discharge to occur within the region; organic pollutants in the waste salt particles entering the reaction discharge region are degraded in the plasma discharge environment.

[0015] The carrier gas in the reaction discharge zone is introduced laterally through the gas distributor, which agitates the fluidized waste salt particles and blows off the solid deposits on the inner wall of the reaction discharge zone.

[0016] Preferably, after the organic pollutants have been degraded, power supply to the electrodes in the reaction discharge zone is stopped; the discharge port is opened, allowing the treated waste salt particles to be discharged from the circulating fluidized reactor with the airflow. Afterwards, gas supply to the first inlet and the gas distributor is stopped.

[0017] Preferably, during the discharge process in the reactive discharge region, the effective dielectric constant within the region is continuously monitored, and the discharge frequency is adjusted to maintain the effective dielectric constant within a target range. The target range for the effective dielectric constant is determined based on the relationship between the effective dielectric constant and the amount of deposited material in the reactive discharge region. The target range is the effective dielectric constant range with the lowest amount of deposited material in the reactive discharge region.

[0018] Preferably, the particle size of the waste salt particles is 122μm to 312μm.

[0019] Preferably, the discharge voltage of the reaction discharge region is 13.7kV to 16.6kV.

[0020] Preferably, the operating parameters are determined using a step-by-step optimization method. These operating parameters include particle size, gas flow rate, gas humidity, and discharge voltage. The step-by-step optimization method involves selecting one operating parameter as the target optimization parameter, while keeping the remaining parameters fixed; sequentially adjusting the target optimization parameter to multiple different candidate values, recording the organic pollutant removal rate and energy efficiency of the waste salt particles, and selecting the optimal candidate value as the target optimization parameter.

[0021] The present invention has the following beneficial effects.

[0022] 1. Simple operation and fast reaction rate: The circulating fluidized bed reactor of this invention enables waste salt particles to circulate in a fluidized state, repeatedly entering the reaction discharge zone of plasma discharge. This allows the waste salt particles to react rapidly with the active particles generated by the discharge in a fully dispersed fluidized state, achieving efficient degradation of organic pollutants. Simultaneously, the circulating fluidized bed reactor of this invention features continuous sample feeding, allowing for continuous processing of waste salt and ensuring the scale of waste salt treatment and the reaction rate.

[0023] 2. Elimination or suppression of wall fouling: This invention incorporates multiple lateral air inlets in the reaction discharge zone. The laterally input carrier gas enhances the disturbance of fluidized waste salt particles within the reaction discharge zone, increasing the reaction rate. Furthermore, it removes deposits from the sidewalls of the reaction discharge zone, significantly reducing wall fouling. Simultaneously, this invention uses an embedded dielectric sensor to detect the effective dielectric constant of the reaction discharge zone. By adjusting the discharge parameters, the effective dielectric constant is controlled within a range that suppresses wall fouling, reducing the conductivity of the waste salt and minimizing electrostatic adsorption on the wall surface. Based on these two reasons, this invention significantly reduces wall fouling, ensuring thorough and uniform treatment of the waste salt, improving the organic matter removal rate, and minimizing damage to the device walls.

[0024] 3. Environmentally friendly and low operating cost: This invention adopts a dry process, avoiding the problem of generating large amounts of wastewater and facilitating the resource utilization of industrial waste salt. Simultaneously, because the dielectric barrier discharge technology uses an insulating dielectric, the electric field can only pass through the micropores, achieving the effect of focusing the electric field, reducing the discharge voltage, improving energy utilization, and thus lowering operating costs.

[0025] 4. Highly efficient removal of organic pollutants: The plasma generated by dielectric barrier discharge in this invention can deeply remove organic impurities from solid waste salt. The plasma-photocatalytic synergistic effect generated by the novel dielectric material greatly improves the removal efficiency of organic impurities and avoids the generation of high salinity and subsequent catalyst recovery treatment. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the circulating fluidized reactor in Embodiment 1 of the present invention.

[0027] Figure 2 This is a flow path diagram of gas and waste salt particles in Embodiment 2 of the present invention.

[0028] Figure 3 This is a comparison chart of pollutant degradation results at different particle sizes in Example 3 of the present invention.

[0029] Figure 4 This is a comparison chart of pollutant treatment energy efficiency under different particle sizes in Example 3 of the present invention.

[0030] Figure 5 This is a comparison chart of pollutant degradation results under different gas flow rates in Example 3 of the present invention.

[0031] Figure 6 This is a comparison chart of pollutant treatment energy efficiency under different gas flow rates in Embodiment 3 of the present invention.

[0032] Figure 7 This is a comparison chart of pollutant degradation results under different gas humidity conditions in Example 3 of the present invention.

[0033] Figure 8 This is a comparison chart of pollutant treatment energy efficiency under different gas humidity conditions in Example 3 of the present invention.

[0034] Figure 9 This is a comparison chart of pollutant degradation results under different discharge voltages in Example 3 of the present invention.

[0035] Figure 10 This is a comparison chart of pollutant treatment energy efficiency under different discharge voltages in Embodiment 3 of the present invention.

[0036] Figure 11 This is a comparison of SEM images of waste salt particles before and after treatment under the optimal operating parameters in Example 3 of the present invention.

[0037] Figure descriptions: 1. Reaction discharge zone; 2. Reflux section; 3. Feeding zone; 4. Gas outlet; 5. Feed inlet; 6. First gas inlet; 7. Discharge outlet; 8. Blower; 9. Filter screen; 10. Electrode; 11. Second gas inlet; 12. Embedded dielectric sensor. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] Example 1 like Figure 1As shown, an industrial waste salt treatment device based on a circulating fluidized bed reactor with dielectric barrier discharge includes a blower 8, a circulating fluidized bed reactor, a storage silo, and a monitoring and control system. The storage silo is used to store the treated waste salt. The circulating fluidized bed reactor has a ring-shaped circulating reaction channel. The circulating reaction channel has a reaction discharge zone 1, a reflux section 2, and a feeding zone 3 connected in a ring. The feeding zone 3 has an outlet 4, a feed inlet 5, a first inlet 6, and an outlet 7 arranged sequentially at intervals along the gas circulation direction. A filter 9 is installed at the outlet 4, allowing only carrier gas to be output, enabling the waste salt particles to continuously flow and react in the circulating reaction channel. The first inlet 6 is connected to the blower 8. The first inlet 6 and the blower 8 are used to continuously input carrier gas into the circulating fluidized bed reactor, driving the waste salt particles to circulate and generate active particles that degrade the waste salt particles in the plasma discharge environment. Both the feed inlet 5 and the outlet 7 are equipped with valves. The feed inlet 5 is connected to the output port at the bottom of the feed silo. The feed hopper and feed inlet 5 are used to input the industrial waste salt particles to be treated into the circulating fluidized reactor before the reaction begins. The discharge outlet 7 is connected to an external storage silo. The discharge outlet 7 is used to output the treated industrial waste salt particles after the reaction is completed.

[0040] Electrodes 10 are provided on both sides of the reaction discharge region 1. The circulating reaction channel acts as a dielectric barrier layer on the tube wall of the reaction discharge region 1. In this embodiment, by inputting a voltage of 15kV and 17kHz to the electrodes 10 on both sides of the reaction discharge region 1, plasma discharge is induced inside the reaction discharge region 1.

[0041] During operation, industrial waste salt particles are input through inlet 5, accompanied by carrier gas continuously input through the air inlet. They pass through reaction discharge zone 1 and reflux section 2, and are then circulated again until the degradation of the industrial waste salt particles is complete. The industrial waste salt particles undergo degradation in the reaction discharge zone 1 of the plasma discharge. In this embodiment, air is used as the carrier gas. In this embodiment, the completion of degradation is indicated by setting the reaction time. After the reaction is complete, the valve of outlet 7 is opened, and the industrial waste salt particles are output. Outlet 7 is connected to a storage silo via a pipeline.

[0042] A gas distributor is provided on the side of the reaction discharge zone 1. The gas distributor includes multiple second air inlets 11 opened on the side of the pipe wall of the reaction discharge zone 1. The first air inlet 6 and the gas distributor are connected to the carrier gas source through a blower 8 and a pipeline. The gas distributor is used to turbulent the airflow in the reaction discharge zone 1 by introducing air from the side. On the one hand, it can improve the fluidization state of the waste salt particles and improve the efficiency of plasma discharge degradation of the waste salt particles in the reaction discharge zone 1. On the other hand, it can also blow off some of the dirt adhering to the wall of the discharge reaction zone.

[0043] An embedded dielectric sensor 12 is installed in the tube wall of the reaction discharge zone 1. The embedded dielectric sensor 12 is used to determine the dielectric constant of the waste salt particles inside the reaction discharge zone 1.

[0044] An embedded dielectric sensor is a type of capacitive sensor with electrodes located on the same plane. It offers advantages such as single-sided penetration, adjustable signal strength, and tomographic imaging. When applying a planar capacitive sensor to a dielectric measurement system, the sensor housing is made of ceramic matrix composite material and placed away from electrode 10 to avoid interference from the discharge electrode 10. The dielectric constant typically affects the electric field distribution and contaminant adsorption behavior. A high dielectric constant leads to interfacial polarization, causing waste salt particles to electrostatically adsorb onto the wall surface, forming a fouling layer. Simultaneously, the fouling layer hinders electric field penetration, resulting in localized temperature increases, accelerating organic carbonization and forming a denser deposition layer. This causes uneven discharge, affecting organic removal and damaging the equipment. Therefore, the embedded dielectric sensor 12 can be used to measure the dielectric constant of waste salt particles in the circulating fluidized bed reactor to determine the severity of fouling in the reaction discharge zone 1. Subsequently, based on the dielectric constant-process parameter correlation model: in, The effective dielectric constant; The basic dielectric constant; These are material property constants; V This is the discharge voltage; f The discharge frequency; t For processing time; τ is the time constant.

[0045] Based on the correlation model between dielectric constant and process parameters, the effective dielectric constant can be changed by controlling the discharge voltage and discharge frequency, thereby eliminating or alleviating the dirty wall phenomenon.

[0046] The monitoring and control system is used to monitor and control the operating parameters of the circulating fluidized reactor and the waste salt input module. These operating parameters include gas flow rate, discharge voltage, and gas humidity.

[0047] In this embodiment, the air inlet is equipped with a rotor flow meter for detecting the flow rate of the carrier gas input to the circulating fluidized reactor.

[0048] In some embodiments, the tube wall medium of the reaction discharge region 1 is made of low dielectric microwave ceramic (ε=3~5), and a CeO2-TiO2 composite catalyst (particle size 20 nm~50 nm, TiO2 loading 5 wt%~15 wt%) is uniformly loaded by the sol-gel method. The plasma-photocatalytic synergistic effect of the CeO2-TiO2 catalyst is utilized to excite ·OH free radicals in the ultraviolet band (λ=300 nm~400 nm) to degrade organic matter.

[0049] Example 2 like Figure 2 As shown, an industrial waste salt treatment method uses the industrial waste salt treatment device provided in Example 1.

[0050] The industrial waste salt treatment method includes the following steps: Step 1: The industrial waste salt to be processed is crushed, screened, and pretreated before being fed into the feed hopper.

[0051] Step 2: Open the valve at inlet 5 to allow the waste salt particles in the feed hopper to enter the circulating reaction channel within the circulating fluidized bed reactor. Simultaneously, continuously supply carrier gas to the air inlet. Based on the flow rate measured by the rotor flow meter, adjust the speed of blower 8 to control the input carrier gas flow rate at 0.2 m / s, thus fluidizing the waste salt.

[0052] Step 3: Set the discharge parameters of the reaction discharge zone 1, start the discharge power supply, and plasma discharge occurs in the reaction discharge zone 1, generating high-energy electrons and active particles. The waste salt particles flowing through the reaction discharge zone 1 come into contact with the high-energy electrons and active particles, and the organic pollutants in the waste salt particles are degraded. As the discharge environment of the device changes, the waste salt particles are modified, the dielectric constant decreases, and the adhesion of particles to the inner wall of the reaction discharge zone 1 is reduced. For particles that form a deposition layer, they are blown off using an air blowing port.

[0053] Simultaneously, the embedded dielectric sensor 12 is activated to measure the dielectric constant of the waste salt particles in the device. The discharge voltage and frequency are dynamically adjusted according to the dielectric constant. The preset range of the dielectric constant is set to 3.6~10. When the dielectric constant is greater than the preset range, the discharge frequency is increased and / or the discharge voltage is decreased to reduce the dielectric constant. When the dielectric constant is lower than the preset range, the discharge frequency is decreased and / or the discharge voltage is increased to increase the dielectric constant. By controlling the dielectric constant within a reasonable range, the waste salt adhering to the inner wall of the reaction discharge zone 1 is removed, and the dirty wall phenomenon is alleviated.

[0054] Step 4: The waste salt particles continue to circulate and degrade in a fluidized state in the circulating reaction channel until the preset reaction time is reached; then, carrier gas is continuously input and the valve of outlet 7 is opened, and the degraded waste salt particles are discharged from outlet 7 from the circulating reaction channel with the carrier gas.

[0055] Step 5: Perform organic composition analysis on the treated waste salt, such as TOC (total organic carbon) analysis, and analyze the impact of each parameter on organic decomposition and energy efficiency through data recording.

[0056] Example 3 An operating parameter optimization method is provided for optimizing multiple operating parameters of the industrial waste salt treatment method provided in Example 2. The specific process is as follows: A certain amount of waste salt from the dyeing and printing industry is weighed and placed inside a circulating fluidized bed reactor. Using freshly prepared media material, the embedded dielectric sensor 12 is activated, and the gas flow rate through the inlet and outlet pipes is controlled by a rotor flowmeter, causing the waste salt to fluidize inside the reactor. A dielectric barrier discharge plasma power supply is then connected for plasma treatment. The optimized operating parameters include particle size, gas velocity, gas humidity, and discharge voltage. The effects of different operating parameters on the organic matter degradation efficiency are recorded during the treatment process to optimize the treatment process.

[0057] (1) Optimization of particle size: Dyeing waste salt with different particle sizes was separated by grinding and sieving. Samples with different particle sizes were placed in a discharge circulating fluidized bed reactor for treatment to investigate the effect of different particle sizes on the TOC removal effect and dielectric constant of the waste salt. When investigating the effect of particle size on the pretreatment effect of dyeing waste salt, 15g of waste salt sample was taken, the gas flow rate was controlled at 0.129m / s, the gas humidity was 11%, the discharge voltage was 20.0 kV, and the average particle sizes were 122μm, 179μm, 236μm, 312μm, and 647μm, respectively. The pollutant removal and energy efficiency were as follows. Figure 3 and Figure 4 As shown in the figure, the processing efficiency is optimal when the particle size is 179 μm.

[0058] (2) Optimization of gas flow rate: Based on the results of the single-factor optimization of particle size, the particle size with the highest TOC removal rate was determined. Using this as a quantitative measure, the effects of different gas flow rates on the TOC removal efficiency and dielectric constant of waste salt were investigated. When investigating the effect of gas flow rate on the pretreatment effect of dyeing and printing waste salt, a 15g waste salt sample was taken, with the particle size controlled at 179μm, gas humidity at 11%, discharge voltage at 20.0 kV, and gas flow rates of 0.043m / s, 0.086m / s, 0.129m / s, 0.151m / s, and 0.172m / s for measurement. The pollutant removal and energy efficiency were as follows: Figure 5 and Figure 6 As shown. Considering all factors, the processing efficiency is optimal when the air velocity is 0.151 m / s; (3) Optimization of gas humidity: Based on the results of the single-factor optimization of gas flow rate, the gas flow rate with the highest TOC removal rate was determined. Using this as a quantitative measure, the effects of different gas humidity levels on the TOC removal efficiency and dielectric constant of waste salt were investigated. When investigating the effect of gas humidity on the pretreatment effect of dyeing and printing waste salt, a 15g waste salt sample was taken, with the particle size controlled at 179μm, the discharge voltage at 20.0 kV, the gas flow rate at 0.151m / s, and the gas humidity at 0%, 11%, 23%, 46%, and 66% for measurement. The pollutant removal and energy efficiency were as follows: Figure 7 and Figure 8As shown. Considering all factors, the optimal processing efficiency is achieved when the gas humidity is 23%. (4) Optimization of discharge voltage: Based on the results of the single-factor optimization of gas humidity, the gas humidity with the highest TOC removal rate was determined. Using this as a quantitative measure, the effects of different discharge voltages on the TOC removal efficiency and dielectric constant of waste salt were investigated. When investigating the effect of discharge voltage on the pretreatment effect of dyeing and printing waste salt, a 15g waste salt sample was taken, with the particle size controlled at 179μm, gas flow rate at 0.151m / s, gas humidity at 23%, and discharge voltages of 10.1kV, 12.2kV, 13.7kV, 15.1kV, and 16.6kV for measurement. The pollutant removal and energy efficiency are as follows: Figure 9 and Figure 10 As shown. Considering all factors, the optimal processing efficiency is achieved when the discharge voltage is 15.1 kV. (5) Optimization of effective dielectric constant: Based on the results of the optimized operating parameters obtained from the above experimental factors, the treatment conditions with the highest TOC removal rate were determined. The changes in dielectric constant and the fouling of the wall surface during the waste salt treatment process were monitored to determine the influence of the effective dielectric constant on the TOC removal effect and the fouling phenomenon. Condition optimization was then performed to obtain an effective dielectric constant with less fouling. Specifically, an embedded dielectric sensor 12 was used to detect the dielectric constant of the waste salt during the discharge treatment process. It was found that the dielectric constant fluctuated continuously with the change in the organic matter content in the waste salt. By controlling the discharge voltage and frequency, the dielectric constant could be controlled, effectively suppressing the fouling phenomenon of the particles. The auxiliary blowing through the blowing port ensured thorough mixing of the waste salt particles in the reaction zone, further improving the treatment efficiency and protecting the device.

[0059] Equal amounts of waste salt from the dyeing and printing industry were placed inside a traditional circulating fluidized bed reactor. Using traditional media materials, the gas flow rate in the pipeline was controlled by a rotor flowmeter to make the waste salt fluidized inside the circulating fluidized bed reactor. A medium barrier discharge plasma power supply was connected for plasma treatment. The treatment was carried out under the same experimental parameters as above, and the TOC removal efficiency of the traditional circulating fluidized bed reactor and the fluidized bed circulating reactor was compared.

[0060] like Figure 11 It can be seen that under optimal parameters, the waste salt treatment method can basically break the structure of waste salt particles, turning them from large-volume spherical particles into broken and irregular small particles. This shows that most of the organic matter is decomposed and treated, and the charge loading capacity is reduced, which reduces the electrostatic adsorption capacity on the wall surface, reduces particle deposition, and greatly alleviates the dirty wall phenomenon.

Claims

1. An industrial waste salt treatment device based on a circulating fluidized bed reactor with dielectric barrier, comprising a circulating fluidized bed reactor; characterized in that: The circulating fluidized reactor is provided with a ring-shaped circulating reaction channel; the circulating reaction channel is provided with a reaction discharge zone (1), a reflux section (2) and a feeding zone (3) connected in a ring in sequence; the feeding zone (3) is provided with an outlet (4), a feed inlet (5), a first air inlet (6) and a discharge outlet (7) arranged in sequence along the gas circulation direction; a filter screen (9) is provided at the outlet (4); the carrier gas input at the first air inlet (6) causes the waste salt particles input at the discharge outlet (7) to enter the fluidized state and circulate along the circulating reaction channel; electrodes (10) are provided on both sides of the reaction discharge zone (1); the circulating reaction channel forms a dielectric barrier layer for plasma discharge on the tube wall of the reaction discharge zone (1); the reaction discharge zone (1) is provided with a gas distributor for lateral input of carrier gas; the reaction discharge zone (1) is provided with an embedded dielectric sensor (12); the embedded dielectric sensor (12) is used to detect the dielectric constant in the reaction discharge zone (1).

2. The industrial waste salt treatment device according to claim 1, characterized in that: It also includes a blower (8); the gas distributor includes multiple second air inlets (11) at different positions on the side of the tube wall of the reaction discharge zone (1); the first air inlet (6) of the feeding zone (3) and the gas distributor are all connected to the blower (8).

3. The industrial waste salt treatment device according to claim 1, characterized in that: Both the feed inlet (5) and the discharge outlet (7) are equipped with valves.

4. The industrial waste salt treatment device according to claim 1, characterized in that: The tube wall medium of the reaction discharge region (1) is microwave ceramic with a dielectric constant of 3 to 5; the inner wall of the reaction discharge region (1) is loaded with CeO2-TiO2 composite catalyst; ultraviolet light is applied to the transparent tube wall of the reaction discharge region (1) during operation.

5. A method for treating industrial waste salt, characterized in that: Use the industrial waste salt treatment device as described in claim 1; The industrial waste salt treatment method includes: Industrial waste salt is crushed and screened into waste salt particles; the discharge port (7) is closed and the waste salt particles are fed into the feed port (5); the carrier gas is fed into the first air inlet (6) and the gas distributor; the flow rate of the carrier gas is greater than the critical fluidization velocity, which causes the waste salt particles to circulate in the circulating reaction channel in a fluidized state. Power is supplied to the electrodes on the reaction discharge zone (1) to cause plasma discharge in the reaction discharge zone (1); the organic pollutants in the waste salt particles that enter the reaction discharge zone (1) are degraded in the plasma discharge environment; The carrier gas is laterally input into the reaction discharge zone (1) through the gas distributor, which disturbs the fluidized waste salt particles and blows off the solid deposits on the inner wall of the reaction discharge zone (1).

6. The industrial waste salt treatment method according to claim 5, characterized in that: After the organic pollutants have been degraded, power supply to the electrodes on the reaction discharge zone (1) is stopped; the discharge port (7) is opened so that the treated waste salt particles are discharged from the discharge port (7) with the airflow from the circulating fluidized reactor; then, the gas supply to the first air inlet (6) and the gas distributor is stopped.

7. The industrial waste salt treatment method according to claim 5, characterized in that: During the discharge process in the reaction discharge zone (1), the effective dielectric constant in the reaction discharge zone (1) is continuously detected. By adjusting the discharge frequency, the effective dielectric constant is kept within the target range. The target range of the effective dielectric constant is determined based on the relationship between the effective dielectric constant and the amount of deposited material in the reaction discharge zone (1). The target range is the effective dielectric constant range with the least amount of deposited material in the reaction discharge zone (1).

8. The industrial waste salt treatment method according to claim 5, characterized in that: The particle size of the waste salt particles is 122μm to 312μm; the discharge voltage of the reaction discharge zone (1) is 13.7kV to 16.6kV.

9. The industrial waste salt treatment method according to claim 5, characterized in that: The operating parameters are determined by a step-by-step optimization method; the operating parameters include particle size, gas flow rate, gas humidity, and discharge voltage; the step-by-step optimization method is as follows: select one operating parameter as the target optimization parameter, and the remaining operating parameters are fixed parameters; adjust multiple different candidate values ​​of the target optimization parameter in sequence, and record the organic pollutant removal rate and energy efficiency of the waste salt particles, and select the best candidate value as the target optimization parameter.

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