Industrial waste salt resource utilization system

Abstract

This utility model relates to the field of industrial waste salt treatment technology, specifically to an industrial waste salt resource utilization system, including a pretreatment unit, on which a compatibility unit, a pyrolysis unit, a dissolution and sorting unit, and a freeze crystallization unit are sequentially connected; the freeze crystallization unit is connected to a first MVR evaporation crystallization unit and a second MVR evaporation crystallization unit; the pyrolysis unit includes an oxygen-insulated box, the inner wall of which is lined with an insulation layer, and a waste salt pyrolysis furnace is fixedly installed inside the oxygen-insulated box, with a shield-shaped spiral pusher installed inside the waste salt pyrolysis furnace, one end of which is connected to a pusher driver located outside the oxygen-insulated box; this utility model places the waste salt pyrolysis furnace and the secondary combustion chamber inside the oxygen-insulated box, ensuring an oxygen-free state during the pyrolysis process, eliminating the need for inert gas protection, and guaranteeing the safe operation of the waste salt pyrolysis furnace and the requirement for full carbonization of organic matter.

Description

Technical Field

[0001] This utility model relates to the field of industrial waste salt treatment technology, specifically to an industrial waste salt resource utilization system. Background Technology

[0002] Industrial waste salt mainly originates from waste salt generated at the end of chemical production and wastewater treatment processes, and generally contains harmful or environmentally polluting components.

[0003] The overall approach to the resource utilization of industrial waste salt is "pyrolysis + impurity removal + salt separation". Pyrolysis processes include high-temperature melting, rotary kiln pyrolysis, and microwave pyrolysis. However, due to the large fluctuations in the composition and eutectic point of industrial waste salt, conventional equipment is prone to problems such as salt buildup and severe corrosion. Furthermore, rotary kiln pyrolysis and microwave pyrolysis processes suffer from incomplete impurity removal, requiring hardening and concentration units, ultimately leading to high investment and operating costs. Therefore, this invention provides a system and process for the resource utilization of industrial waste salt. Utility Model Content

[0004] To address the aforementioned problems, this utility model provides a high-performance, low-cost industrial waste salt resource utilization system that can solve the problems of insufficient continuous stability of waste salt pyrolysis, low online rate of core pyrolysis equipment, long waste salt resource utilization process, and low purity of by-products.

[0005] This utility model discloses an industrial waste salt resource utilization system, which includes a pretreatment unit, and the pretreatment unit is sequentially connected to a compatibility unit, a pyrolysis unit, a dissolution and sorting unit, and a freeze crystallization unit.

[0006] The freeze crystallization unit is connected to a first MVR evaporation crystallization unit and a second MVR evaporation crystallization unit.

[0007] The pyrolysis unit includes an oxygen-free heat preservation box, the inner wall of which is covered with an insulation layer. A waste salt pyrolysis furnace is fixedly installed inside the oxygen-free heat preservation box, and a shield-shaped spiral pusher is installed inside the waste salt pyrolysis furnace. One end of the shield-shaped spiral pusher is connected to a pusher driver located outside the oxygen-free heat preservation box.

[0008] One end of the waste salt pyrolysis furnace is equipped with a waste salt feed pipe that extends upward into an oxygen-free and heat-insulating box, and the other end of the waste salt pyrolysis furnace is equipped with a discharge device at the bottom.

[0009] A secondary combustion chamber is also fixedly installed inside the oxygen-insulated box above the waste salt pyrolysis furnace. The secondary combustion chamber is connected to the waste salt pyrolysis furnace through a pyrolysis gas discharge pipe. An exhaust gas discharge pipe extending out of the oxygen-insulated box is also installed on the secondary combustion chamber. A pyrolysis flue gas treatment device is connected to the exhaust gas discharge pipe.

[0010] It also includes a secondary combustion chamber burner located outside the oxygen-insulated box, with one end of the secondary combustion chamber burner passing through the oxygen-insulated box and extending into the secondary combustion chamber.

[0011] Preferably, the pretreatment unit is a low-temperature energy-saving drying device or a crusher.

[0012] Preferably, the discharge device includes a pyrolysis discharge screw conveyor, one end of which is welded to the inner wall of one side of the oxygen-free insulation box, and the other end of which extends out from the other side of the oxygen-free insulation box and is connected to a waste salt discharge port.

[0013] The pyrolysis discharge screw conveyor is connected in sequence to a discharge gearbox and a discharge motor located outside the oxygen-free insulated box at the end furthest from the waste salt discharge port.

[0014] Preferably, the waste salt pyrolysis furnace is also connected to a fault salt discharge port located outside the oxygen-free insulation box at the end near the waste salt feed pipe.

[0015] Preferably, the dissolution and sorting unit includes a pyrolysis salt dissolution device, which is connected to a first-stage hydrocyclone separator. The first-stage hydrocyclone separator is provided with a top-level discharge pipe and a bottom-level discharge pipe. The top-level discharge pipe is connected to a second-stage hydrocyclone concentrator, and the bottom-level discharge pipe is connected to a first solid-liquid separator.

[0016] The secondary cyclone concentrator is equipped with a supernatant discharge pipe and a concentrate discharge pipe. The supernatant discharge pipe is connected to the freeze crystallization unit through a filter device.

[0017] A second solid-liquid separator is connected to the concentrated liquid discharge pipe;

[0018] Both the first and second solid-liquid separators are connected to a liquid outlet pipe, which is connected to the filtration device.

[0019] This invention places the waste salt pyrolysis furnace and the secondary combustion chamber inside an oxygen-free and heat-insulating box, ensuring an oxygen-free state during the pyrolysis process. It eliminates the need for inert gas protection, thus guaranteeing the safe operation of the waste salt pyrolysis furnace and meeting the requirements for full carbonization of organic matter.

[0020] This invention utilizes a waste salt pyrolysis furnace and a secondary combustion chamber set up inside an oxygen-free insulated box to solve the problems of insufficient continuous stability and low online rate in waste salt pyrolysis.

[0021] This invention utilizes a pretreatment unit that is sequentially connected to a compatibility unit, a pyrolysis unit, a dissolution and sorting unit, a freeze crystallization unit, and an MVR evaporation crystallization unit to achieve the resource utilization of waste salt. The waste salt resource utilization process is short and the by-products have high purity.

[0022] This utility model features an ultra-short waste salt resource utilization process. The special pyrolysis process can remove TOC and render impurity ions insoluble. Therefore, the pyrolyzed mixed salt can be directly prepared into a high-concentration brine of 20% to 25%m without the need for separate impurity removal units, such as coagulation clarification hardening removal units, resin hardening removal units, etc., as well as the salt concentration limit (generally below 6%m) and increased water volume caused by setting up these units. The brine then directly enters the evaporation and crystallization unit, which significantly reduces the energy consumption cost and investment required for disposal.

[0023] This utility model adopts a stable and reliable pyrolysis device, which is continuous, stable, safe and reliable, with an online rate of ≥95%. At the same time, the special structure and operating conditions can remove TOC while solidifying impurity metal ions, which greatly reduces the pretreatment requirements for downstream resource recovery.

[0024] This novel freezing technology employs a combination of two methods: refrigerant cooling and vacuum flash cooling. If the sodium chloride / sodium sulfate ratio in the mixed salt is ≥3, vacuum flash cooling can be used. In this method, the residual heat from the direct dissolution of the pyrolysis salt can remove some of the moisture, thus reducing the energy consumption of the subsequent sodium chloride crystallization. For other compositions, refrigerant cooling (controlled at -5℃) is used to achieve absolute separation of the mixed salt. This makes the entire crystallization technology more widely applicable and more economical.

[0025] The entire process water is self-circulating and there is no wastewater discharge. The regenerated water produced by back-end evaporation and crystallization can be used for dissolving impurities after front-end pyrolysis and for backwashing the filter. The production water only needs to be supplemented by water lost due to natural causes.

[0026] This invention can better separate soluble components from waste salt, and through pyrolysis, sorting and filtration, can produce high-quality by-products. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the system connection of this utility model.

[0028] Figure 2 This is a schematic diagram of the pyrolysis unit structure in this utility model.

[0029] Figure 3 for Figure 2 Left view.

[0030] Figure 4 This is a flow chart of the dissolution and sorting process.

[0031] Attached reference numerals: 1-Oxygen-free insulation box, 2-Insulation layer, 3-Secondary combustion chamber, 4-Secondary combustion chamber burner, 5-Waste salt pyrolysis furnace, 6-Shield-shaped screw conveyor, 7-Pushing gearbox, 8-Pushing motor, 9-Pyrolysis furnace discharge pipe, 10-Pyrolysis discharge screw conveyor, 11-Discharge gearbox, 12-Discharge motor, 13-Waste salt inlet pipe, 14-Waste salt outlet, 15-Waste gas exhaust pipe, 16-Support, 17-Secondary combustion chamber fixture, 18-Pyrolysis gas exhaust pipe, 19-Faulty salt discharge port, 20-Maintenance manhole. Detailed Implementation

[0032] The following is in conjunction with the appendix Figures 1-3 This utility model will be described below.

[0033] See appendix Figure 1 This utility model discloses an industrial waste salt resource utilization system, which includes a pretreatment unit, and the pretreatment unit is sequentially connected to a compatibility unit, a pyrolysis unit, a dissolution and sorting unit, and a freeze crystallization unit.

[0034] The freeze crystallization unit is connected to a first MVR evaporation crystallization unit and a second MVR evaporation crystallization unit.

[0035] See appendix Figure 2-3 The pyrolysis unit includes an oxygen-free heat preservation box 1, and the inner wall of the oxygen-free heat preservation box 1 is covered with a heat insulation layer 2. A waste salt pyrolysis furnace 5 is fixedly installed inside the oxygen-free heat preservation box 1. A shield-shaped spiral pusher 6 is installed inside the waste salt pyrolysis furnace 5. One end of the shield-shaped spiral pusher 6 is connected to a pusher driver located outside the oxygen-free heat preservation box 1.

[0036] The waste salt pyrolysis furnace 5 is provided with a waste salt feed pipe 13 extending upward from the oxygen-free heat preservation box 1 at one end, and a discharge device is provided at the lower part of the other end of the waste salt pyrolysis furnace 5.

[0037] A secondary combustion chamber 3 is also fixedly installed inside the oxygen-insulated box 1 above the waste salt pyrolysis furnace 5. The secondary combustion chamber 3 is fixedly connected to the oxygen-insulated box 1 through the secondary combustion chamber fixer 17. The secondary combustion chamber 3 is connected to the waste salt pyrolysis furnace 5 through the pyrolysis gas discharge pipe 18. The secondary combustion chamber 3 is also provided with an exhaust gas discharge pipe 15 extending out of the oxygen-insulated box 1. A pyrolysis flue gas treatment device is connected to the exhaust gas discharge pipe 15.

[0038] It also includes a secondary combustion chamber burner 4 installed outside the oxygen-insulated box 1. One end of the secondary combustion chamber burner 4 passes through the oxygen-insulated box 1 and extends into the secondary combustion chamber 3. The fuel gas and auxiliary fuel gas enter the secondary combustion chamber 3 through the secondary combustion chamber burner 4 to ignite and heat the furnace. Under the heat insulation effect of the oxygen-insulated box 1, a heating atmosphere is formed, so that the waste salt pyrolysis furnace 5 inside the oxygen-insulated box 1 is heated as a whole. This ensures the uniformity of heating of the waste salt pyrolysis furnace 5, completely solves the problem of coking or salt adhesion caused by uneven heating, and further ensures the continuous and reliable operation of this equipment.

[0039] In one embodiment, the pretreatment unit is a low-temperature energy-saving drying device or a crusher.

[0040] In one embodiment, see Figure 2 The waste salt pyrolysis furnace 5 is a hollow column, and its two ends are welded to the inner walls of the oxygen-insulating and heat-preserving box 1 on both sides respectively.

[0041] The peripheral surface of the waste salt pyrolysis furnace 5 is surrounded by three cylindrical arc surfaces, two of which are arranged side by side and the other is the third arc surface. The two side-by-side arc surfaces that are close to each other are connected, and the two arc surfaces that are far apart from each other are connected through the third arc surface.

[0042] The central axes of the three cylindrical arc surfaces are set parallel to each other;

[0043] Pyrolysis furnace discharge pipes 9 are provided on both parallel arc surfaces, and the pyrolysis furnace discharge pipes 9 are connected to the discharge device.

[0044] A shield-shaped spiral feeder 6 is installed in each of the two parallel arc surfaces.

[0045] Two waste salt feed pipes 13 are provided on the third arc surface, and the two waste salt feed pipes 13 are respectively provided in the areas where the two parallel arc surfaces are located.

[0046] The diameters of the circles containing the two parallel arc surfaces are equal.

[0047] The shield-shaped spiral feeder 6 is a shield-shaped spiral feeder 6 whose size matches the cylindrical arc surface it is located on.

[0048] Two waste salt pyrolysis furnaces 5 are provided, which are arranged in parallel to each other, and the two waste salt pyrolysis furnaces 5 are respectively connected to the secondary combustion chamber 3 through the pyrolysis gas discharge pipe 18.

[0049] The discharge device includes a pyrolysis discharge screw conveyor 10. One end of the pyrolysis discharge screw conveyor 10 is welded to the inner wall of one side of the oxygen-free insulation box 1, and the other end of the pyrolysis discharge screw conveyor 10 extends out from the other side of the oxygen-free insulation box 1 and is connected to a waste salt discharge port 14.

[0050] The end of the pyrolysis discharge screw conveyor 10 away from the waste salt discharge port 14 is connected in sequence to the discharge gearbox 11 and the discharge motor 12, which are located outside the oxygen-free insulation box 1.

[0051] The pusher driver includes a connected pusher motor 8, which is connected to the shield-shaped spiral pusher 6 via a pusher gearbox 7.

[0052] The waste salt pyrolysis furnace 5 is also connected to a fault salt discharge port 19 located outside the oxygen-free insulation box 1 at one end near the waste salt feed pipe 13.

[0053] The oxygen-free insulated box 1 is also equipped with a maintenance manhole 20.

[0054] In one embodiment, the dissolution and sorting unit includes a pyrolysis salt dissolution device, which is connected to a first-stage hydrocyclone separator. The first-stage hydrocyclone separator is provided with a top-level discharge pipe and a bottom-level discharge pipe. The top-level discharge pipe is connected to a second-stage hydrocyclone concentrator, and the bottom-level discharge pipe is connected to a first solid-liquid separator.

[0055] The secondary cyclone concentrator is equipped with a supernatant discharge pipe and a concentrate discharge pipe. The supernatant discharge pipe is connected to the freeze crystallization unit through a filter device.

[0056] A second solid-liquid separator is connected to the concentrated liquid discharge pipe;

[0057] Both the first and second solid-liquid separators are connected to a liquid outlet pipe, which is connected to the filtration device.

[0058] An industrial waste salt resource utilization process, employing an industrial waste salt resource utilization system for treatment, the process includes the following steps:

[0059] Pretreatment is carried out according to the specific conditions of the waste salt. If the water content of the waste salt is greater than 10% by weight, the pretreatment is drying the waste salt. If the size of the waste salt is greater than 5mm, the pretreatment is crushing the waste salt. The pretreatment is for wet waste salt with a water content greater than 10%, flaky waste salt, blocky waste salt, etc. Among them, wet waste salt is dried using low-temperature energy-saving drying equipment, such as fluidized bed drying equipment or belt drying equipment. Flaky waste salt and blocky waste salt are crushed using a crusher, such as a hammer crusher, jaw crusher or impact crusher.

[0060] The pretreated waste salt undergoes compositional analysis, specifically testing for each inorganic salt component and the total organic carbon (TOC) value. It is also categorized according to melting point: generally by eutectic point not exceeding 500℃, 500-600℃, and not less than 600℃, and then placed into separate raw material tanks.

[0061] Then, as needed, various types of waste salt are transported and mixed by metering screws, and then fed into the waste salt pyrolysis furnace 5 for pyrolysis from the waste salt feed pipe 13.

[0062] The formulation is based on the feed composition requirements of the waste salt pyrolysis furnace 5. Generally, it involves mixing and homogenizing different raw materials or different batches of raw materials in a certain proportion for temperature-sensitive components such as moisture, sodium chloride, sodium sulfate, and sodium nitrate. The mixing method can be pit mixing, fractional screw feeding, or other methods.

[0063] Waste salt entering the waste salt pyrolysis furnace 5 is slowly conveyed from one end to the other end by the shield-shaped spiral feeder 6 built into the waste salt pyrolysis furnace 5. The heat generated by the continuous combustion in the secondary combustion chamber 3 located in the oxygen-free heat preservation box 1 heats the waste salt in the waste salt pyrolysis furnace 5, and controls the temperature in the oxygen-free heat preservation box 1 to be 500~800℃. TOC in the waste salt is pyrolyzed into carbon in the oxygen-free environment, and some impurities react with oxygen-containing substances to generate metal oxides. After pyrolysis, it enters the discharge device.

[0064] The waste gas generated after the pyrolysis of waste salt enters the secondary combustion chamber 3 for combustion and is treated by the pyrolysis flue gas treatment device to meet the standards before being discharged.

[0065] The mixed salts after waste salt pyrolysis are discharged from the waste salt pyrolysis furnace 5 through a discharge device. The discharged mixed salts are first cooled by circulating cooling water and then sent to a dissolving and stirring tank. Alternatively, the discharged mixed salts are first sent to a dissolving and stirring tank, dissolved, and then cooled as needed. The dissolving residence time is not less than 1 hour, resulting in concentrated brine containing a certain amount of solid insoluble matter. This insoluble matter mainly includes carbon particles and metal oxides. To ensure the effectiveness of dissolution, a buffer tank with stirring is usually set up after the dissolving tank to ensure thorough dissolution and stable concentration and water volume.

[0066] The concentrated brine containing a certain amount of solid insoluble matter is first pumped to a primary hydrocyclone separator. The primary hydrocyclone separator separates and concentrates the heavier solid insoluble matter from the lighter solid insoluble matter. The concentrated heavier solid insoluble matter is then separated into solid and liquid by a filter press or centrifuge. The supernatant after solid-liquid separation is further concentrated by a secondary hydrocyclone concentrator and then separated into solid and liquid again by a filter press or centrifuge.

[0067] In actual use, such as Figure 4 As shown, the primary hydrocyclone separator separates the concentrated brine into underflow and supernatant. The underflow has a low water volume and high solid content, mainly containing metal oxides; the supernatant has a high water volume and low solid content, mainly carbon particles. The underflow is buffered and filtered to obtain a high-ash by-product rich in metal oxides; the supernatant is then pumped to the secondary hydrocyclone concentrator.

[0068] The secondary cyclone concentrator concentrates the insoluble matter in the supernatant entering the secondary cyclone concentrator; thus obtaining the concentrated liquid at the bottom and the clear liquid at the top. The clear liquid at the top is sent to the rear-end freeze crystallization unit after passing through a filter; the concentrated liquid is filtered to obtain high-carbon by-products; the high-carbon products and high-ash products generated after dissolution and sorting are recycled and reused according to the surrounding industrial environment.

[0069] The solid-liquid separation equipment typically uses one of the following, depending on the amount of insoluble matter: a plate and frame filter press, a bag filter, etc.

[0070] The filtrates from the solid-liquid separation by the primary hydrocyclone separator and the secondary hydrocyclone concentrator are mixed to form a high-concentration brine, which is then filtered and enters the freeze crystallization unit.

[0071] The FX-PU series equipment can be selected for the primary hydrocyclone separator and the secondary hydrocyclone concentrator;

[0072] The high-concentration brine is first pre-cooled to a temperature below 25 degrees Celsius before entering the cryo-crystallizer in the cryo-crystallization unit. The temperature in the cryo-crystallizer is controlled between -5 and 0 degrees Celsius to crystallize components whose solubility decreases sharply with decreasing temperature, and then separated by solid-liquid separation equipment.

[0073] The separated clear liquid is then heat-exchanged and sent to the first MVR evaporation and crystallization unit for evaporation and crystallization to obtain the first by-product, which is sodium chloride.

[0074] The separated solids are redissolved and then passed through the second MVR evaporation and crystallization unit to obtain a second byproduct, which is sodium sulfate.

[0075] The cryo-crystallization unit cools the high-concentration brine (20%–30%) from the source to -5–0 degrees Celsius, where sodium sulfate typically crystallizes out as hydrated sodium sulfate, usually sodium sulfate decahydrate. Solid-liquid separation is achieved using a centrifuge. The separated solid is then redissolved and passed through a second MVR evaporation crystallization unit to obtain sodium sulfate. Two cooling methods are used in this cryo-crystallization: direct cooling, where the refrigerant generated by the ice machine directly exchanges heat with the heat exchanger attached to the process, and flash cooling, where the vapor vacuum of the crystallizer is increased for flash cooling. Flash cooling is preferred when the sodium chloride / sodium sulfate ratio in the high-concentration brine is greater than 3; otherwise, direct cooling is used. The cryo-crystallizer can be an Oslo crystallizer, a DTB crystallizer, or another type.

[0076] The first MVR evaporation crystallization unit is an MVR evaporation crystallizer, and the second MVR evaporation crystallization unit is an MVR sodium sulfate crystallizer.

[0077] High-concentration brine is processed by a freeze crystallization centrifuge in a freeze crystallization unit to produce sodium sulfate, which is usually sodium sulfate decahydrate. It typically needs to be dissolved again and recrystallized by evaporation crystallization to finally produce high-quality anhydrous sodium sulfate. The sodium sulfate crystallizer is of the MVR type, with an operating temperature of 85~95 degrees Celsius, and the crystallizer is of the FC type.

[0078] The sodium chloride crystallization is carried out using an MVR evaporator crystallizer, with the crystallizer operating temperature typically between 85 and 95 degrees Celsius. This process evaporates the frozen mother liquor and crystallizes it to precipitate high-quality sodium chloride, thereby achieving solid-liquid separation of sodium chloride and water. The crystallizer is of the FC type.

[0079] The pyrolysis flue gas treatment device cools, denitrates, and desulfurizes the flue gas generated in the waste salt pyrolysis furnace 5, ultimately achieving emission standards. The specific process combination is determined by the harmful components in the waste salt being treated. The final emitted flue gas meets national and industry emission standards. The pyrolysis flue gas treatment device is a conventional technology.

[0080] This process produces no external drainage; only periodic water replenishment is required. Regenerated water is generated through evaporation and crystallization. Backwash water is regenerated via a coagulation and sedimentation unit, while sludge is discharged into a high-carbon byproduct filter press. Generally, the regenerated water from evaporation and crystallization is used to dissolve salts after pyrolysis, and the clarified permeate from coagulation is used for filtration and backwashing. All necessary dissolved water and backwash water are generated by the system and stored in a buffer tank to meet overall system requirements.

[0081] The high-ash byproducts of this process are generally a mixture of calcium oxide, magnesium oxide, aluminum oxide, and silicon dioxide. The composition depends on the impurities in the waste salt raw material. Depending on the concentration, they can be used as raw materials for magnesium slag recycling, polyaluminum production, etc. The carbon-rich byproducts generally contain a certain proportion of high-ash inorganic matter and enriched carbon. After dehydration, they can be used as fuel for co-firing.

[0082] The quality of the by-product sodium sulfate can reach or exceed the Class II Grade 1 quality standard of GB / T6009-2014 "Industrial Anhydrous Sodium Sulfate"; the quality of the by-product sodium chloride can reach or exceed the Grade 1 standard of GB / T5462-2015 "Industrial Salt".

Claims

1. An industrial waste salt resource utilization system, comprising a pretreatment unit, characterized in that, The pretreatment unit is sequentially connected to a compatibility unit, a pyrolysis unit, a dissolution and sorting unit, and a freeze crystallization unit. The freeze crystallization unit is connected to a first MVR evaporation crystallization unit and a second MVR evaporation crystallization unit. The pyrolysis unit includes an oxygen-free heat preservation box, the inner wall of which is covered with an insulation layer. A waste salt pyrolysis furnace is fixedly installed inside the oxygen-free heat preservation box, and a shield-shaped spiral pusher is installed inside the waste salt pyrolysis furnace. One end of the shield-shaped spiral pusher is connected to a pusher driver located outside the oxygen-free heat preservation box. One end of the waste salt pyrolysis furnace is equipped with a waste salt feed pipe that extends upward into an oxygen-free and heat-insulating box, and the other end of the waste salt pyrolysis furnace is equipped with a discharge device at the bottom. A secondary combustion chamber is also fixedly installed inside the oxygen-insulated box above the waste salt pyrolysis furnace. The secondary combustion chamber is connected to the waste salt pyrolysis furnace through a pyrolysis gas discharge pipe. An exhaust gas discharge pipe extending out of the oxygen-insulated box is also installed on the secondary combustion chamber. A pyrolysis flue gas treatment device is connected to the exhaust gas discharge pipe. It also includes a secondary combustion chamber burner located outside the oxygen-insulated box, with one end of the secondary combustion chamber burner passing through the oxygen-insulated box and extending into the secondary combustion chamber.

2. The industrial waste salt resource utilization system as described in claim 1, characterized in that, The pretreatment unit is a low-temperature energy-saving drying device or a crusher.

3. The industrial waste salt resource utilization system as described in claim 1, characterized in that, The discharge device includes a pyrolysis discharge screw conveyor. One end of the pyrolysis discharge screw conveyor is welded to the inner wall of one side of the oxygen-free insulation box, and the other end of the pyrolysis discharge screw conveyor passes through the other side of the oxygen-free insulation box and is connected to a waste salt discharge port. The end of the pyrolysis discharge screw conveyor furthest from the waste salt discharge port is sequentially connected to a discharge gearbox and a discharge motor located outside the oxygen-free insulated box.

4. The industrial waste salt resource utilization system as described in claim 3, characterized in that, The waste salt pyrolysis furnace is also connected to a fault salt discharge port located outside the oxygen-free insulation box at one end near the waste salt feed pipe.

5. The industrial waste salt resource utilization system as described in claim 1, characterized in that, The dissolution and sorting unit includes a pyrolysis salt dissolution device, which is connected to a first-stage hydrocyclone separator. The first-stage hydrocyclone separator is equipped with a top-level discharge pipe and a bottom-level discharge pipe. The top-level discharge pipe is connected to a second-stage hydrocyclone concentrator, and the bottom-level discharge pipe is connected to a first solid-liquid separator. The secondary cyclone concentrator is equipped with a supernatant discharge pipe and a concentrate discharge pipe. The supernatant discharge pipe is connected to the freeze crystallization unit through a filter device. A second solid-liquid separator is connected to the concentrated liquid discharge pipe; Both the first and second solid-liquid separators are connected to a liquid outlet pipe, which is connected to the filtration device.

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