Device for treating byproduct carnallite through supercritical carbon dioxide extraction

Abstract

The utility model discloses a device for treating byproduct carnallite through supercritical carbon dioxide extraction, and belongs to the field of industrial wastewater treatment. The device for treating the byproduct carnallite through supercritical carbon dioxide extraction comprises a carbon dioxide storage tank, a carbon dioxide compressor communicated with the carbon dioxide storage tank and a mixing and stirring tank communicated with the carbon dioxide, and a carnallite feeding machine is arranged at the feeding end of the mixing and stirring tank. A solid-liquid separator is arranged at the output end of the mixing and stirring tank, and a decompression separator is arranged at the liquid discharging end of the solid-liquid separator. The device for treating the byproduct carnallite through supercritical carbon dioxide extraction is simple in structure and convenient to use, the carbon dioxide compressor and the mixing and stirring tank are arranged, the device is used for treating the byproduct carnallite, the operation temperature is low, energy consumption is low, secondary pollution is not generated in the treatment process, and the device is more environmentally friendly; the byproduct impurity salt is harmlessly treated, so that the hazardous waste treatment cost is saved, and meanwhile, the recycled industrial salt has a certain economic value.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial wastewater treatment, in particular to a device for extracting and treating by-product salts using supercritical carbon dioxide. Background Art

[0002] Industrial wastewater treatment systems, especially zero-emission systems, will produce a large amount of by-product salts. The by-product salts have a high organic content, are difficult to comprehensively utilize, and are likely to cause environmental pollution. They are generally defined as hazardous waste.

[0003] There are currently several treatment methods for reproducing miscellaneous salt:

[0004] 1. High temperature burning treatment: The by-product salt is heated to 500-800℃, and most of the organic matter will be oxidized and removed. The remaining solid salt is mainly a mixture of sodium sulfate and sodium chloride, and then the salt is separated and recycled.

[0005] 2. Dissolution-Advanced Oxidation Treatment: Dissolve the by-product salts in water, then perform advanced oxidation treatment to remove organic matter in the water, and then separate the salt for resource utilization. Common methods of advanced oxidation include Fenton method, ozone catalytic oxidation, wet oxidation, etc.

[0006] However, the disadvantages of high-temperature incineration treatment are high treatment temperature and high cost; the exhaust gas produced is prone to secondary pollution, and the cost of exhaust gas treatment is high; when using dissolution-advanced oxidation treatment, the COD of the salt water solution is very high, and the Fenton and ozone catalytic oxidation methods have poor treatment effects; the wet oxidation method has a good treatment effect, but the equipment investment cost and operating cost are too high.

[0007] Therefore, the utility model provides a device for extracting and treating by-product salts with supercritical carbon dioxide to solve the above problems. Utility Model Content

[0008] 1. Technical issues to be solved

[0009] The utility model provides a device for processing by-product impure salts by supercritical carbon dioxide extraction, aiming to solve the problems of high cost and poor effect of the existing by-product impure salt processing device proposed in the background technology.

[0010] (II) Technical solution

[0011] To achieve the above purpose, the utility model provides the following technical solutions: a device for extracting and treating by-product impure salts with supercritical carbon dioxide, in order to solve the problem of high cost and poor effect of the re-production impure salt treatment device, comprising a carbon dioxide storage tank, a carbon dioxide compressor connected to the carbon dioxide storage tank, and a mixing and stirring tank connected to the carbon dioxide compressor, the feed end of the mixing and stirring tank is provided with an impure salt feeder, the output end of the mixing and stirring tank is provided with a solid-liquid separator, the liquid discharge end of the solid-liquid separator is provided with a decompression separator, and the gaseous discharge end of the decompression separator is connected to the carbon dioxide storage tank. Re-production of impure salts by treating with carbon dioxide saves the cost of hazardous waste treatment, and the industrial salt recovered as a resource has certain economic value.

[0012] Preferably, in order to solve the problem of carbon dioxide rapidly changing to a supercritical state, the carbon dioxide compressor is used to heat and pressurize carbon dioxide, the heating temperature is 31.5-40°C, and the pressurization pressure is 7.5-10MPa. By setting appropriate temperature and pressure, carbon dioxide can quickly change state in the carbon dioxide compressor.

[0013] Preferably, in order to solve the problem of separation efficiency of the solid-liquid separator, the solid-liquid separator is a hydrocyclone or a precision filter. The use of a centrifuge or membrane separation technology can improve the separation efficiency and reduce the content of organic matter remaining in the supercritical carbon dioxide.

[0014] Preferably, in order to solve the problem of pressure safety of the mixing and stirring tank and the decompression separator, the mixing and stirring tank, the solid-liquid separator and the decompression separator are all provided with a pressure monitoring component. The pressure monitoring component can be used to accurately control the pressure, which helps to improve separation efficiency and product quality and reduce energy consumption.

[0015] Preferably, in order to solve the problem of processing the insoluble salt separated by the solid-liquid separator, the solid discharge end of the solid-liquid separator is connected to a salt separation and recycling system. The separated solid salt can enter the salt separation and recycling system for further processing.

[0016] Preferably, in order to solve the problem of handling the remaining organic matter, the solid discharge end of the decompression separator is connected to the incineration system. The remaining solid organic matter can be sent to a roasting furnace and roasted in an air-tight manner to obtain a biomass activated carbon product.

[0017] (III) Beneficial effects

[0018] The device for treating by-product salts by supercritical carbon dioxide extraction has a simple structure and is easy to use. By arranging a carbon dioxide compressor and a mixing and stirring tank, the device is used to treat by-product salts. The operating temperature is low, the energy consumption is low, and the treatment process does not generate secondary pollution, which is more environmentally friendly. The by-product salts are harmlessly treated, saving the cost of hazardous waste treatment. At the same time, the industrial salt recovered as a resource has certain economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The overall structure diagram of a device for extracting and treating by-product salts with supercritical carbon dioxide;

[0020] Figure 2 The present invention is a process flow chart for the treatment of by-product salts by supercritical carbon dioxide extraction.

[0021] In the figure: 1. Carbon dioxide storage tank; 2. Miscellaneous salt feeder; 3. Carbon dioxide compressor; 4. Mixing and stirring tank; 5. Solid-liquid separator; 6. Decompression separator. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] The utility model provides a device for extracting and treating by-product salts by supercritical carbon dioxide, such as Figure 1-2 As shown, the device for supercritical carbon dioxide extraction and treatment of by-product impurities includes a carbon dioxide storage tank 1, a carbon dioxide compressor 3 connected to the carbon dioxide storage tank 1, and a mixing and stirring tank 4 connected to the carbon dioxide compressor 3, the feed end of the mixing and stirring tank 4 is provided with an impurity salt feeder 2, the output end of the mixing and stirring tank 4 is provided with a solid-liquid separator 5, the solid discharge end of the solid-liquid separator 5 is connected to the salt separation and resource utilization system, the liquid discharge end of the solid-liquid separator 5 is provided with a pressure reduction separator 6, the gaseous discharge end of the pressure reduction separator 6 is connected to the carbon dioxide storage tank 1, and the solid discharge end of the pressure reduction separator 6 is connected to the incineration system.

[0024] When in use, the carbon dioxide is first heated and pressurized by the carbon dioxide compressor 3 to become a supercritical state. The supercritical carbon dioxide has an extremely low viscosity, a density close to that of a liquid, and a diffusivity close to that of a gas, and can effectively dissolve a variety of organic matter; the supercritical carbon dioxide and the by-product salts are then sent to the mixing and stirring tank 4, and after being stirred and fully contacted, the organic matter in the by-product salts is dissolved into the supercritical carbon dioxide; in the solid-liquid separator 5, the supercritical carbon dioxide in which a large amount of organic matter is dissolved is separated from the insoluble salt, and the separated solid salt enters the salt separation and resource utilization system for further treatment; the supercritical carbon dioxide enters the decompression separator 6, and due to the reduction in pressure, the carbon dioxide becomes gaseous again, and enters the carbon dioxide storage tank 1 under pressure for recycling, and the remaining organic matter is dissolved and becomes solid, and the solid organic matter is sent to the incineration system for treatment.

[0025] Specifically, the carbon dioxide compressor 3 is used to heat and pressurize the carbon dioxide, the heating temperature is 31.5-40° C., and the pressurization pressure is 7.5-10 MPa, ensuring that the carbon dioxide can quickly become a supercritical state after entering the carbon dioxide compressor 3.

[0026] More specifically, the solid-liquid separator 5 is a hydrocyclone separator or a precision filter, which can separate the undissolved solid salt from the supercritical carbon dioxide.

[0027] Furthermore, the mixing tank 4, the solid-liquid separator 5 and the vacuum separator 6 are all provided with pressure monitoring components; the pressure monitoring components can accurately understand the pressure values ​​in the mixing tank 4, the solid-liquid separator 5 and the vacuum separator 6, which helps to improve separation efficiency and product quality and reduce energy consumption. Among them, the pressure monitoring component can be an absolute pressure sensor.

[0028] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for extracting and treating by-product salts with supercritical carbon dioxide, characterized in that: The invention comprises a carbon dioxide storage tank (1), a carbon dioxide compressor (3) connected to the carbon dioxide storage tank (1), and a mixing and stirring tank (4) connected to the carbon dioxide compressor (3); a feed end of the mixing and stirring tank (4) is provided with a salt feeder (2); an output end of the mixing and stirring tank (4) is provided with a solid-liquid separator (5); a liquid discharge end of the solid-liquid separator (5) is provided with a pressure reducing separator (6); and a gas discharge end of the pressure reducing separator (6) is connected to the carbon dioxide storage tank (1).

2. The device for extracting and treating by-product salts with supercritical carbon dioxide according to claim 1, characterized in that: The carbon dioxide compressor (3) is used to heat and pressurize carbon dioxide, the heating temperature is 31.5-40° C., and the pressurization pressure is 7.5-10 MPa.

3. The device for extracting and treating by-product salts with supercritical carbon dioxide according to claim 1, characterized in that: The solid-liquid separator (5) is a hydrocyclone separator or a precision filter.

4. The device for extracting and treating by-product salts with supercritical carbon dioxide according to claim 1, characterized in that: The mixing and stirring tank (4), the solid-liquid separator (5) and the pressure reducing separator (6) are all provided with pressure monitoring components.

5. The device for extracting and treating by-product salts with supercritical carbon dioxide according to claim 1, characterized in that: The solid material discharge end of the solid-liquid separator (5) is connected to a salt separation and resource utilization system.

6. The device for extracting and treating by-product salts with supercritical carbon dioxide according to claim 1, characterized in that: The solid material discharge end of the decompression separator (6) is connected to the incineration system.

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