A solid and hazardous waste salt regeneration device and method

Abstract

The present invention discloses a solid and hazardous waste salt regeneration device and method. The content of the present invention includes: a solid and hazardous waste salt refining system, a baking soda reaction system, a product refining system and an ammonium chloride system. The solid and hazardous waste salt refining system obtains refined salt through high-temperature cracking, dissolution, refining, evaporation and centrifugation. The refined salt is respectively fed into the baking soda reaction system and the ammonium chloride system. The baking soda reaction system uses the ammonium chloride system to salt out the mother liquor and the refined salt to react, adjust the particle size, and obtain baking soda through centrifugation. The ammonium chloride system uses the remaining mother liquor of the baking soda reaction system, adds refined salt to precipitate ammonium chloride, and performs subsequent operations to finally obtain the by-product ammonium chloride; the product refining system uses the baking soda produced by the baking soda reaction system to decompose by heat to obtain soda ash. The present invention can achieve sufficient treatment of solid and hazardous waste salt with a simple series of devices, realize the comprehensive utilization of waste salt resources, reduce treatment costs, and improve economic benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of resource regeneration, and in particular to a device and method for regenerating solid and hazardous waste salt. Background Art

[0002] According to incomplete statistics, the fine chemical industry, high-concentration wastewater, printing and dyeing, pharmaceuticals, pesticides, metallurgical industry, phosphorus chemical industry, new energy industry, lithium iron phosphate, ternary positive electrode materials, coal chemical industry and other industries produce more than 30 million tons of solid and hazardous waste salt annually, and the solid and hazardous waste salt itself contains a variety of harmful substances.

[0003] If not adequately treated, solid salts containing complex organic hazardous waste will pose a serious threat to the environment; and solid salts containing complex organic hazardous waste are also concentrated resources, and their degree of danger and environmental damage are not necessarily greater than other chemical products. However, as long as they are in accordance with regulatory requirements and the resource utilization disposal process is reasonably designed, they can produce huge social benefits and significant economic benefits.

[0004] Currently, the main methods for disposing solid and hazardous waste salt in China include landfill, high-temperature oxidation, and salt washing. Landfill is the primary method for disposing solid and hazardous waste salt in my country, but it presents several challenges: high investment, large land occupation, and soil pollution; a limited number of rigid landfills in China; and high landfill costs, ranging from 2,500 to 4,000 yuan per ton of waste salt, depending on the region, making it unaffordable for most companies. Furthermore, solid and hazardous waste salt contains many valuable chemical resources that are not properly recycled, resulting in significant waste. Both high-temperature oxidation and salt washing require complex equipment for pollution-free treatment, resulting in higher costs.

[0005] Existing technical solutions, such as the hazardous waste salt pyrolysis system with authorization announcement number CN 215175077 U, remove organic impurities from hazardous waste salts through a pretreatment device, a pyrolysis reactor, and a gas purification and recovery device, while simultaneously purifying and utilizing the generated dry gas and pyrolysis gas. However, this pyrolysis system is limited to the removal of impurities and the purification and utilization of gases, and does not convert hazardous waste salts into economically valuable products, nor does it fully process and utilize waste salt resources.

[0006] For example, the process method for regenerating organic hazardous waste solid salt resources containing complex components, with authorization announcement number CN 109911917 B, focuses on cleaning and drying the organic hazardous waste solid salt, and oxidizing and decomposing the hazardous waste solid salt particles after cleaning and drying, and separating various salt varieties through a multi-stage salt separation process. There is no detailed regeneration device, and there is no description of the overall regeneration device for solid hazardous waste salt. In addition, the entire regeneration process is relatively complicated, requires various auxiliary agents, and is quite costly.

[0007] In order to solve the above technical problems, the present invention proposes a solid and hazardous waste salt regeneration device and method. Summary of the Invention

[0008] The purpose of the present invention is to overcome the shortcomings of the existing technology and propose a solid and hazardous waste salt regeneration device and method, which can fully treat solid and hazardous waste salt with a simple series of devices and methods, realize the comprehensive utilization of waste salt resources, reduce treatment costs, and improve economic benefits.

[0009] To achieve the above objectives, the present invention proposes the following technical solutions:

[0010] A solid and hazardous waste salt regeneration device, comprising a solid and hazardous waste salt refining system, a baking soda reaction system, a product refining system and an ammonium chloride system;

[0011] The solid and hazardous waste salt refining system includes a high-temperature cracking furnace, a dissolving tank, a refining kettle, an evaporation system and a first centrifuge, which are connected in sequence through pipelines; the high-temperature cracking furnace is provided with a waste salt receiving pipeline for receiving solid and hazardous waste salt; the refining kettle is provided with a reagent input pipe and a carbon-based adsorbent input pipe, and the refining kettle is provided with a first output pipe and a second output pipe, the first output pipe is connected to the evaporation system, and the second output pipe discharges impurities; the first centrifuge is provided with a first mother liquor reflux pipeline, which is connected to the evaporation system, and the mother liquor after centrifugal separation in the first centrifuge is returned to the evaporation system for further evaporation until the refined salt is fully extracted; the first centrifuge is provided with a refined salt output pipeline, which is divided into three branch pipelines, namely the first branch pipeline, the second branch pipeline and the third branch pipeline.

[0012] The baking soda reaction system includes a multi-channel reactor, a particle size adjustment kettle, a second centrifuge, a double-pass baking soda reactor and a third centrifuge, which are connected in sequence through pipelines; the multi-channel reactor is provided with three input pipes, namely a first input pipe, a second input pipe and a third input pipe, the first input pipe is connected to the first branch of the refined salt output pipe of the first centrifuge, and the third input pipe is a reactant slurry input pipe.

[0013] The particle size adjustment kettle is provided with a promoter input pipe; the second centrifuge is provided with a single-pass solid output pipeline and a first mother liquor output pipeline, and the first mother liquor output pipeline is connected to the double-pass baking soda reactor; the double-pass baking soda reactor is connected to the second branch of the refined salt output pipeline of the first centrifuge; the third centrifuge is provided with a double-pass solid output pipeline and a second mother liquor output pipeline.

[0014] The product refining system includes a baking soda refining kettle, a high-temperature countercurrent alkali-making tower, a dryer and a hydrator. The baking soda refining kettle is provided with two baking soda output pipes, namely a first baking soda output pipe and a second baking soda output pipe, which are respectively connected to the high-temperature countercurrent alkali-making tower and the dryer; the baking soda refining kettle is respectively connected to a one-way solid output pipe and a two-way solid output pipe; the dryer is provided with a third baking soda output pipe, which outputs the dried baking soda; the hydrator is connected to the high-temperature countercurrent alkali-making tower, and the hydrator is provided with a heavy soda ash output pipe.

[0015] The ammonium chloride system includes a cold precipitation crystallizer, a cold precipitation thickener, a salting-out crystallizer, a salting-out thickener and a fourth centrifuge. The cold precipitation crystallizer is connected to the second mother liquor output pipeline. The cold precipitation crystallizer is provided with two output pipes, namely a third output pipe and a fourth output pipe, which are respectively connected to the cold precipitation thickener and the salting-out crystallizer; the salting-out crystallizer is connected to the third branch of the refined salt output pipeline of the first centrifuge. The salting-out crystallizer is provided with a third mother liquor output pipeline, which is connected to the second input pipe of the multi-channel reactor; the salting-out crystallizer is provided with a fifth output pipe, which is connected to the salting-out thickener; the salting-out thickener is provided with a second mother liquor reflux pipeline, which is connected to the salting-out crystallizer; the salting-out thickener is provided with a slurry output pipeline, which is connected to the cold precipitation crystallizer; the cold precipitation thickener is provided with an overflow clear liquid output pipeline, the fourth centrifuge is provided with a fourth mother liquor output pipeline, the overflow clear liquid output pipeline and the fourth mother liquor output pipeline merge with the second mother liquor reflux pipeline and flow into the salting-out crystallizer; the fourth centrifuge is provided with an ammonium chloride output pipeline.

[0016] Preferably, the high-temperature cracking furnace uses fuel gas as a heat source to provide heat for solid and hazardous waste salts; the high-temperature cracking furnace is provided with a fuel gas channel, one end of the fuel gas channel is connected to the fuel gas supply channel, and the other end of the fuel gas channel leads to the cracking furnace interlayer, and the fuel gas is passed into the interlayer of the cracking furnace and burned by the combustion device, so that heat is conducted through the furnace wall of the cracking furnace, and the solid and hazardous waste salts are indirectly in contact with the heat source. The solid and hazardous waste salts are anaerobically cracked under high temperature conditions, and large molecular organic matter is cracked into small molecular organic gas; a fuel gas supplementary channel is provided between the inside of the cracking furnace and the cracking furnace interlayer, a one-way valve is provided in the fuel gas supplementary channel, and a bag dust collector is provided. The amount of gas containing small molecular organic matter gradually increases, so that the one-way valve is opened, and after passing through the bag dust collector to remove large dust particles, the gas enters the interlayer of the cracking furnace as fuel, which can be used as a supplement to the heat source for cracking solid and hazardous waste salts.

[0017] Preferably, the dissolving tank dissolves the cracked solid and hazardous waste salts at a suitable temperature and pressure to form a solid and hazardous waste salt solution.

[0018] Preferably, the refining kettle is equipped with a plate-and-frame filter. A reagent and a carbon-based adsorbent are added to the solid and hazardous waste salt solution after cracking, and then filtered through the plate-and-frame filter to obtain a high-purity sodium chloride solution. The above-mentioned reagents and carbon-based adsorbents are chemical agents commonly used in the sodium chloride preparation process in the prior art.

[0019] Preferably, the evaporation system evaporates and crystallizes the refined high-purity sodium chloride solution to precipitate solid sodium chloride.

[0020] Preferably, the first centrifuge separates the solid-liquid mixture after the evaporation system, and the separated mother liquor is returned to the evaporation system for further evaporation until the fixed sodium chloride is fully precipitated, and the separated solid sodium chloride is input into the baking soda reaction system and the ammonium chloride system to produce baking soda, soda ash and ammonium chloride products.

[0021] Preferably, the multi-channel reactor and the two-way baking soda reactor are both equipped with multiple separate reaction units, each reaction unit is a separate reaction system, and the reaction solution is evenly distributed to each reaction unit, so that the reaction process is dispersed into multiple reaction units, so that the reaction is more uniform and sufficient.

[0022] Preferably, a reactant slurry, i.e., the reactant required for the alkali production process, is added into the multi-channel reactor, and baking soda can be generated in the first step of the Hou alkali production process, which is a commonly used alkali production process in the prior art.

[0023] Preferably, the particle size adjustment kettle adds an accelerator to the solution that has fully reacted in the multi-channel reactor. Under the action of the accelerator, the solid particles are enlarged, and the particle size of 98% of the baking soda can be controlled to be 50-150 mesh, which is more conducive to solid-liquid separation. The accelerator used here is a chemical agent commonly used in the prior art to increase particle size.

[0024] Preferably, the second centrifuge performs solid-liquid separation on the solution adjusted by the particle size adjustment kettle, and the separated solid is a one-way solid, which is transported to the baking soda refining kettle, and the mother liquor flows into the two-way baking soda reactor.

[0025] Preferably, the double-pass baking soda reactor receives refined sodium chloride, and the refined sodium chloride is further reacted with the mother liquor separated by the second centrifuge. The solid produced by the reaction is a double-pass solid, and the double-pass solid is transported to the baking soda refining kettle.

[0026] Preferably, the baking soda refining kettle refines solid baking soda on the single-pass solid and the double-pass solid, removes ammonium chloride, ammonium bicarbonate and sodium chloride in the single-pass + double-pass solid, so that the refined baking soda product can meet the industrial-grade baking soda standards.

[0027] Preferably, the dryer dries the refined baking soda in the baking soda refining kettle to generate a finished baking soda product.

[0028] Preferably, the high-temperature countercurrent alkali tower decomposes baking soda (NaHCO3) to produce soda ash (NaCO3), and the chemical formula is: 2NaHCO3=NaCO3+CO2+H2O.

[0029] Preferably, the hydration machine uses soda ash to prepare dense soda ash through solid phase hydration. Dense soda ash has a higher density than light soda ash. Dense soda ash is mainly used in industries such as glass, metallurgy and pigments.

[0030] Preferably, the cold crystallizer receives the mother liquor from the third centrifuge and performs cold crystallization, the salting-out crystallizer performs salting-out crystallization on the mother liquor after cold crystallization, the mother liquor overflowing from the salting-out crystallizer is returned to the multi-channel reactor for reaction again, and the mother liquor from the cold crystallizer simultaneously flows into the cold thickener to increase the viscosity, and then enters the fourth centrifuge for solid-liquid separation, thereby obtaining the final ammonium chloride product; the crystals in the salting-out crystallizer enter the salting-out thickener to increase the viscosity, and the slurry returns to the cold crystallizer for cold precipitation, and then increases the viscosity to facilitate centrifugation; the clear liquid overflowing from the cold thickener, the mother liquor after separation from the fourth centrifuge, and the overflow mother liquor from the salting-out thickener are all returned to the salting-out crystallizer for re-crystallization, forming a cycle and repeated refining.

[0031] Preferably, the temperature of the cold crystallizer is controlled at 10°C.

[0032] Preferably, the temperature in the salting-out crystallizer is set to 278K ~ 283K (i.e., 5°C ~ 10°C). Utilizing the principle that NH4Cl has a lower solubility than NaCl at low temperatures, adding fine salt powder to the second mother liquor at 278K ~ 283K (i.e., 5°C ~ 10°C) can cause NH4Cl to crystallize alone.

[0033] Another object of the present invention is to disclose a method for regenerating solid and hazardous waste salt, characterized in that:

[0034] ①High-temperature cracking, dissolution, refining, evaporation, crystallization and separation of solid and hazardous waste salt to obtain refined salt;

[0035] ② After the refined salt enters the baking soda system, it reacts with the mother liquor of the salting-out crystallizer to produce small-particle baking soda. The particle size is increased and centrifuged to obtain a single-pass solid. The mother liquor continues to react in the double-pass baking soda reactor to obtain a double-pass solid.

[0036] ③ Single-pass solid and double-pass solid refined baking soda, the refined baking soda is dried to obtain the finished product; the refined baking soda is subjected to thermal decomposition to produce soda ash, which is then hydrated to produce heavy soda ash;

[0037] ④ The mother liquor in the double-pass baking soda reactor is subjected to cold precipitation crystallization. After cold precipitation crystallization, the mother liquor enters the salting-out crystallizer, refined sodium chloride is added, ammonium chloride is precipitated, and the slurry is thickened by salting-out. The slurry returns to the cold precipitation crystallizer, the slurry in the cold precipitation crystallizer is subjected to cold precipitation and thickening, and ammonium chloride is obtained after centrifugation.

[0038] Specifically, solid and hazardous waste salt is sent into the high-temperature cracking furnace through a conveying device. The cracking furnace uses fuel gas as a heat source. The fuel gas is passed into the interlayer of the cracking furnace and burned through the combustion device. The heat is indirectly transferred to the solid and hazardous waste salt through the cracking furnace wall, cracking the large molecular organic matter in the solid and hazardous waste salt into small molecular organic gas. The gas containing small molecular organic matter passes through the bag dust collector to remove large dust particles, and then enters the interlayer of the cracking furnace as fuel to supplement the heat source for cracking the solid and hazardous waste salt.

[0039] The cracked solid hazardous waste salt is passed through a dissolving tank to form a solid hazardous waste salt solution, which then enters a refining kettle to make a sodium chloride solution. By adding reagents and carbon-based adsorbents to the solution, and then passing through a plate and frame filter, a high-purity sodium chloride solution is obtained. The sodium chloride solution enters the evaporation system and is crystallized by evaporation to form sodium chloride solid, which is then separated by the first centrifuge. The separated mother liquor is returned to the evaporation system for further evaporation.

[0040] The solid sodium chloride produced by the solid and hazardous waste salt refining system is fed into a multi-channel reactor through a metering device. The mother liquor of the salting-out crystallizer reacts with the reactant slurry in the multi-channel reactor to generate small-particle baking soda. The reaction slurry at this time is pumped into the particle size adjustment kettle. An equivalent promoter is added to the particle size adjustment kettle. Under the action of the promoter, the solid particles can be increased to ensure that the baking soda particle size is controlled at 50-150 mesh after solid-liquid separation.

[0041] The mother liquor after solid-liquid separation in the second centrifuge enters the double-pass baking soda reactor, and further reacts with the refined sodium chloride in the double-pass baking soda reactor to generate solids as double-pass solids. The double-pass solids enter the product refining system, and the mother liquor after separation in the second centrifuge enters the ammonium chloride system.

[0042] The single-pass solid obtained by the second separator and the double-pass solid obtained by the third separator are sent to the baking soda refining kettle through a conveying device. Ammonium chloride, ammonium bicarbonate, sodium chloride, etc. entrained in the single-pass solid and the double-pass solid are removed in the baking soda refining kettle, so that the refined baking soda product meets the industrial-grade baking soda standard. The solid separated by the baking soda refining kettle enters the baking soda dryer through a conveying device, and is dried to obtain industrial-grade baking soda or a special desulfurization agent product; the baking soda refining kettle also sends the baking soda into a high-temperature countercurrent alkali tower through a conveying device, and decomposes it under heat to obtain a soda ash product. The soda ash is then passed through a hydration machine to obtain heavy soda ash.

[0043] The mother liquor from the third centrifuge is sent to the cold precipitation crystallizer, where it is cooled by external chilled water. The temperature of the cold precipitation crystallizer is controlled at 10°C. Ammonium chloride solid is precipitated from the solution in the cold precipitation crystallizer, and the ammonium chloride-containing slurry enters the cold precipitation thickener. When the solid content in the cold precipitation thickener reaches about 50%, the fourth centrifuge is used to separate the product ammonium chloride. The separated mother liquor and the clear liquid overflowing from the cold precipitation thickener are sent to the central cylinder of the salting-out crystallizer through a conveying device for further crystallization.

[0044] The clear liquid overflowing from the cold crystallizer flows through the overflow port into the central barrel of the salting-out crystallizer. Simultaneously, refined sodium chloride is added to the central barrel of the salting-out crystallizer to react with the mother liquor overflowing from the cold crystallizer. Through the common ion effect, ammonium chloride solids are precipitated. The ammonium chloride slurry from the salting-out crystallizer enters the salting-out thickener. When the solids content in the thickener reaches 40-50%, the thickener slurry is fed into the cold crystallizer. The mother liquor overflowing from the salting-out crystallizer returns to the multi-channel reactor to continue producing baking soda.

[0045] The chemical equations involved in the whole process are as follows:

[0046] NaCl+CO2+NH3+H2O=NaHCO3↓+NH4Cl

[0047] 2NaHCO3=Na2CO3+H2O+CO2↑

[0048] The high-temperature cracking furnace, dissolving tank, refining kettle, evaporation system, multi-channel reactor, particle size adjustment kettle, double-pass baking soda reactor, baking soda refining kettle, high-temperature countercurrent alkali tower, dryer, hydration machine, cold precipitation crystallizer, cold precipitation thickener, salting-out crystallizer, and salting-out thickener used in the above-mentioned process are chemical technology equipment already available in the prior art.

[0049] The beneficial effects of the present invention are:

[0050] The present invention uses a series of processing devices including a solid and hazardous waste salt refining system, a baking soda reaction system, a product refining system and an ammonium chloride system to convert solid and hazardous waste salts generated in industries such as fine chemicals, chemical fibers, pesticides, pharmaceuticals and pesticide and pharmaceutical intermediates, and coal chemical industry into refined salt, baking soda, soda ash and ammonium chloride, thereby achieving maximum resource optimization and solving the problem of waste salt treatment in the industry. At the same time, industrial-grade soda ash, baking soda and special desulfurization agents are regenerated for sale, and the ammonium chloride obtained as a by-product can be sold as agricultural fertilizer, thereby improving the economic benefits of the enterprise and reducing operating costs.

[0051] The present invention realizes the regeneration of solid hazardous waste salt through a series of simple devices. The regeneration process is relatively simple, the steps are simple, and the auxiliary agents are all common chemical agents, which reduces the processing cost, improves the utilization rate of waste salt resources, and improves economic benefits.

[0052] By adopting the above scheme, the present invention can fully treat solid and hazardous waste salt with a simple series of devices, realize the comprehensive utilization of waste salt resources, and at the same time avoid pollution to the ecological environment to the greatest extent, reduce treatment costs, and bring economic benefits to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0054] Figure 1 It is the overall process device diagram of the present invention.

[0055] Figure 2 It is the overall process flow chart of the present invention. Implementation Method

[0056] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0057] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0058] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0059] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0060] like Figure 1 As shown, a solid and hazardous waste salt regeneration device includes a solid and hazardous waste salt refining system, a baking soda reaction system, a product refining system and an ammonium chloride system;

[0061] The solid and hazardous waste salt refining system includes a high-temperature cracking furnace, a dissolving tank, a refining kettle, an evaporation system and a first centrifuge, which are connected in sequence through pipelines; the high-temperature cracking furnace is provided with a waste salt receiving pipeline for receiving solid and hazardous waste salt; the refining kettle is provided with a reagent input pipe and a carbon-based adsorbent input pipe, and the refining kettle is provided with a first output pipe and a second output pipe, the first output pipe is connected to the evaporation system, and the second output pipe discharges impurities; the first centrifuge is provided with a first mother liquor reflux pipeline, which is connected to the evaporation system, and the mother liquor after centrifugal separation in the first centrifuge is returned to the evaporation system for further evaporation until the refined salt is fully extracted; the first centrifuge is provided with a refined salt output pipeline, which is divided into three branch pipelines, namely the first branch pipeline, the second branch pipeline and the third branch pipeline.

[0062] The baking soda reaction system includes a multi-channel reactor, a particle size adjustment kettle, a second centrifuge, a double-pass baking soda reactor and a third centrifuge, which are connected in sequence through pipelines; the multi-channel reactor is provided with three input pipes, namely a first input pipe, a second input pipe and a third input pipe, the first input pipe is connected to the first branch of the refined salt output pipe of the first centrifuge, and the third input pipe is a reactant slurry input pipe.

[0063] The particle size adjustment kettle is provided with a promoter input pipe; the second centrifuge is provided with a single-pass solid output pipeline and a first mother liquor output pipeline, and the first mother liquor output pipeline is connected to the double-pass baking soda reactor; the double-pass baking soda reactor is connected to the second branch of the refined salt output pipeline of the first centrifuge; the third centrifuge is provided with a double-pass solid output pipeline and a second mother liquor output pipeline.

[0064] The product refining system includes a baking soda refining kettle, a high-temperature countercurrent alkali-making tower, a dryer and a hydrator. The baking soda refining kettle is provided with two baking soda output pipes, namely a first baking soda output pipe and a second baking soda output pipe, which are respectively connected to the high-temperature countercurrent alkali-making tower and the dryer; the baking soda refining kettle is respectively connected to a one-way solid output pipe and a two-way solid output pipe; the dryer is provided with a third baking soda output pipe, which outputs the dried baking soda; the hydrator is connected to the high-temperature countercurrent alkali-making tower, and the hydrator is provided with a heavy soda ash output pipe.

[0065] The ammonium chloride system includes a cold precipitation crystallizer, a cold precipitation thickener, a salting-out crystallizer, a salting-out thickener and a fourth centrifuge. The cold precipitation crystallizer is connected to the second mother liquor output pipeline. The cold precipitation crystallizer is provided with two output pipes, namely a third output pipe and a fourth output pipe, which are respectively connected to the cold precipitation thickener and the salting-out crystallizer; the salting-out crystallizer is connected to the third branch of the refined salt output pipeline of the first centrifuge. The salting-out crystallizer is provided with a third mother liquor output pipeline, which is connected to the second input pipe of the multi-channel reactor; the salting-out crystallizer is provided with a fifth output pipe, which is connected to the salting-out thickener; the salting-out thickener is provided with a second mother liquor reflux pipeline, which is connected to the salting-out crystallizer; the salting-out thickener is provided with a slurry output pipeline, which is connected to the cold precipitation crystallizer; the cold precipitation thickener is provided with an overflow clear liquid output pipeline, the fourth centrifuge is provided with a fourth mother liquor output pipeline, the overflow clear liquid output pipeline and the fourth mother liquor output pipeline merge with the second mother liquor reflux pipeline and flow into the salting-out crystallizer; the fourth centrifuge is provided with an ammonium chloride output pipeline.

[0066] like Figure 2 As shown, solid hazardous waste salt is sent into the high-temperature cracking furnace through a conveying device. The cracking furnace uses fuel gas as a heat source. The fuel gas is passed into the interlayer of the cracking furnace and burned by the combustion device. The heat is indirectly transferred to the solid hazardous waste salt through the cracking furnace wall, and the large molecular organic matter in the solid hazardous waste salt is cracked into small molecular organic gas. The gas containing small molecular organic matter passes through a bag dust collector to remove large dust particles, and then enters the interlayer of the cracking furnace as fuel to supplement the heat source for cracking the solid hazardous waste salt.

[0067] The cracked solid hazardous waste salt is passed through a dissolving tank to form a solid hazardous waste salt solution, which then enters a refining kettle to make a sodium chloride solution. By adding reagents and carbon-based adsorbents to the solution, and then passing through a plate and frame filter, a high-purity sodium chloride solution is obtained. The sodium chloride solution enters the evaporation system and is crystallized by evaporation to form sodium chloride solid, which is then separated by the first centrifuge. The separated mother liquor is returned to the evaporation system for further evaporation.

[0068] The solid sodium chloride produced by the solid and hazardous waste salt refining system is fed into a multi-channel reactor through a metering device. The mother liquor of the salting-out crystallizer reacts with the reactant slurry in the multi-channel reactor to generate small-particle baking soda. The reaction slurry at this time is pumped into the particle size adjustment kettle. An equivalent promoter is added to the particle size adjustment kettle. Under the action of the promoter, the solid particles can be increased to ensure that the baking soda particle size is controlled at 50-150 mesh after solid-liquid separation.

[0069] The mother liquor after solid-liquid separation in the second centrifuge enters the double-pass baking soda reactor, and further reacts with the refined sodium chloride in the double-pass baking soda reactor to generate solids as double-pass solids. The double-pass solids enter the product refining system, and the mother liquor after separation in the second centrifuge enters the ammonium chloride system.

[0070] The single-pass solid obtained by the second separator and the double-pass solid obtained by the third separator are sent to the baking soda refining kettle through a conveying device. Ammonium chloride, ammonium bicarbonate, sodium chloride, etc. entrained in the single-pass solid and the double-pass solid are removed in the baking soda refining kettle, so that the refined baking soda product meets the industrial-grade baking soda standard. The solid separated by the baking soda refining kettle enters the baking soda dryer through a conveying device, and is dried to obtain industrial-grade baking soda or a special desulfurization agent product; the baking soda refining kettle also sends the baking soda into a high-temperature countercurrent alkali tower through a conveying device, and decomposes it under heat to obtain a soda ash product. The soda ash is then passed through a hydration machine to obtain heavy soda ash.

[0071] The mother liquor from the third centrifuge (abbreviated as MI) is sent to the cold precipitation crystallizer. In the cold precipitation crystallizer, the temperature of the cold precipitation crystallizer is cooled by external chilled water. The temperature of the cold precipitation crystallizer is controlled at 10°C. Ammonium chloride solid is precipitated from the solution in the cold precipitation crystallizer. The ammonium chloride slurry enters the cold precipitation thickener. When the solid content in the cold precipitation thickener reaches about 50%, the fourth centrifuge is used to separate the product ammonium chloride. The separated mother liquor and the clear liquid overflowing from the cold precipitation thickener are sent to the central cylinder of the salting-out crystallizer through a conveying device for further crystallization.

[0072] The clear liquid overflowing from the cold crystallizer (referred to as semi-MII) flows by gravity through the overflow port into the central barrel of the salting-out crystallizer. Simultaneously, refined sodium chloride is added to the central barrel of the salting-out crystallizer to react with the mother liquor overflowing from the cold crystallizer. Through the common ion effect, ammonium chloride solids are precipitated. The ammonium chloride slurry from the salting-out crystallizer enters the salting-out thickener. When the solids content in the thickener reaches 40-50%, the thickener slurry is fed into the cold crystallizer. The mother liquor overflowing from the salting-out crystallizer (referred to as MII) returns to the multi-channel reactor to continue producing baking soda.

[0073] 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 scope of protection of the present invention.

Claims

1. A solid and hazardous waste salt regeneration device, characterized by: It includes a solid and hazardous waste salt refining system, a baking soda reaction system, a product refining system and an ammonium chloride system; the solid and hazardous waste salt refining system includes a high-temperature cracking furnace, a dissolving tank, a refining kettle, an evaporation system and a first centrifuge, which are connected in sequence through pipelines; the high-temperature cracking furnace is provided with a waste salt receiving pipeline; the refining kettle is provided with a reagent input pipe and a carbon-based adsorbent input pipe, and the refining kettle is provided with a first output pipe and a second output pipe, the first output pipe is connected to the evaporation system, and the second output pipe discharges impurities; the first centrifuge is provided with a first mother liquor reflux pipe connected to the evaporation system; the first centrifuge is provided with a refined salt output pipe, which is divided into three branch pipes, namely the first branch pipe, the second branch pipe and the third branch pipe; The baking soda reaction system includes a multi-channel reactor, a particle size adjustment kettle, a second centrifuge, a two-way baking soda reactor and a third centrifuge, which are connected in sequence by pipelines; the multi-channel reactor is provided with three input pipes, namely a first input pipe, a second input pipe and a third input pipe, the first input pipe is connected to the first branch pipe, and the third input pipe is a reactant slurry input pipe; the particle size adjustment kettle is provided with a accelerator input pipe; the second centrifuge is provided with a single-way solid output pipe and a first mother liquor output pipe, the first mother liquor output pipe is connected to the two-way baking soda reactor; the two-way baking soda reactor is connected to the second branch pipe; the third centrifuge is provided with a two-way solid output pipe and a second mother liquor output pipe; The product refining system includes a baking soda refining kettle, a high-temperature countercurrent alkali-making tower, a dryer and a hydrator. The baking soda refining kettle is provided with two baking soda output pipes, which are respectively connected to the high-temperature countercurrent alkali-making tower and the dryer; the baking soda refining kettle is respectively connected to a single-pass solid output pipe and a two-pass solid output pipe; the hydrator is connected to the high-temperature countercurrent alkali-making tower; The ammonium chloride system includes a cold precipitation crystallizer, a cold precipitation thickener, a salting-out crystallizer, a salting-out thickener and a fourth centrifuge, wherein the cold precipitation crystallizer is connected to the second mother liquor output pipeline, the cold precipitation crystallizer is provided with a third output pipe and a fourth output pipe, which are respectively connected to the cold precipitation thickener and the salting-out crystallizer; the salting-out crystallizer is connected to the third branch pipeline, the salting-out crystallizer is provided with a third mother liquor output pipeline, which is connected to the second input pipe of the multi-channel reactor; the salting-out crystallizer is provided with a fifth output pipe connected to the salting-out thickener; the salting-out thickener is provided with a second mother liquor reflux pipeline connected to the salting-out crystallizer; the salting-out thickener is provided with a slurry output pipeline connected to the cold precipitation crystallizer; the cold precipitation thickener is provided with an overflow clear liquid output pipeline, the fourth centrifuge is provided with a fourth mother liquor output pipeline, and the overflow clear liquid output pipeline and the fourth mother liquor output pipeline merge with the second mother liquor reflux pipeline.

2. The solid and hazardous waste salt regeneration device according to claim 1, characterized in that: The high-temperature cracking furnace is provided with a gas channel, one end of the gas channel is connected to the gas supply channel, and the other end of the gas channel leads to the cracking furnace interlayer.

3. The solid and hazardous waste salt regeneration device according to claim 1, characterized in that: A fuel gas supplementary channel is provided between the interior of the cracking furnace and the interlayer of the cracking furnace. A one-way valve is provided in the fuel gas supplementary channel, and a bag dust collector is provided.

4. The solid and hazardous waste salt regeneration device according to claim 1, characterized in that: The refining kettle is provided with a plate and frame filter.

5. The solid and hazardous waste salt regeneration device according to claim 1, characterized in that: The multi-channel reactor has multiple separate reaction units built in it.

6. The solid and hazardous waste salt regeneration device according to claim 1, characterized in that: The double-pass baking soda reactor has multiple separate reaction units built in.

7. A method for regenerating solid and hazardous waste salt using the device according to any one of claims 1 to 6, characterized in that: Contains the following sections: ①High-temperature cracking, dissolution, refining, evaporation, crystallization and separation of solid and hazardous waste salt to obtain refined salt; ② The refined salt reacts with the mother liquor of the salting-out crystallizer to produce small-sized baking soda, the particle size is increased, and the single-pass solid is obtained by centrifugation. The mother liquor continues to react in the double-pass baking soda reactor to obtain the double-pass solid; ③ Single-pass solid and double-pass solid refined baking soda, the refined baking soda is dried to obtain the finished product; the refined baking soda is decomposed into soda ash by heat, and hydrated to obtain heavy soda ash; ④ The mother liquor in the double-pass baking soda reactor is subjected to cold precipitation crystallization. After cold precipitation crystallization, the mother liquor enters the salting-out crystallizer, refined salt is added, ammonium chloride is precipitated, and the slurry is thickened by salting-out. The slurry returns to the cold precipitation crystallizer, and the slurry in the cold precipitation crystallizer is subjected to cold precipitation and thickening, and ammonium chloride is obtained after centrifugation.

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