A fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery device

Abstract

The application relates to the chemical technology field and discloses a fluorinated phosphate system hydrogen fluoride, hydrogen chloride and nitrogen separation and recovery device, which comprises a compressor, a filter, an adsorption tower, a nitrogen buffer tank, a condenser, a gas-liquid separation tank and a falling-film absorber; the output end of the compressor is connected with the filter; the output end of the filter is connected with the adsorption tower; the output end of the adsorption tower is connected with the condenser and the nitrogen buffer tank respectively; and the output end of the condenser is connected with the gas-liquid separation tank. The new process adsorption tower is used to separate tail gas, which has important significance in safety, environmental protection and economy, can thoroughly separate hydrogen fluoride, hydrogen chloride, nitrogen and other substances, and can return the hydrogen fluoride and nitrogen to the system for reuse, and can make the hydrogen chloride into liquid hydrogen chloride and high-quality hydrochloric acid for sale. The device can effectively reduce the waste acid production amount and increase the whole process economic benefits while realizing the full and reasonable utilization of resources.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, specifically to a device for separating and recovering hydrogen fluoride, hydrogen chloride, and nitrogen in a fluorinated phosphate system. Background Technology

[0002] With technological advancements and improved living standards, the electronics and information industry and the electric vehicle industry are developing rapidly. The increasing use of laptops, mobile phones, handheld tools, electric vehicles, and energy storage power stations is driving a surge in demand for high-energy chemical power sources. This places increasingly higher demands on battery performance and capacity. Ion batteries, due to their excellent electrical performance, safety, environmental friendliness, high energy density, high operating voltage, and long lifespan, are highly valued and have broad application prospects. Fluorinated phosphates are the main raw material for manufacturing ion battery electrolytes. Due to their good ionic conductivity and electrochemical stability, they are currently the most commonly used electrolyte salts. Against the backdrop of my country's energy structure adjustment, and with the mature application of energy storage batteries and new energy vehicles, the demand for fluorinated phosphates in batteries is increasing dramatically. As an ion battery electrolyte, fluorinated phosphates are mainly used in power batteries, energy storage batteries, and other everyday batteries, and are an irreplaceable ion battery electrolyte in the near and medium term.

[0003] Fluorophosphates use large amounts of nitrogen as a carrier gas and protective gas during storage, reaction, and drying. Due to the influence of nitrogen, hydrogen chloride and hydrogen fluoride in the exhaust gas cannot be recovered by condensation. The emitted nitrogen also faces the disadvantage of containing large amounts of acidic gases such as hydrogen fluoride and hydrogen chloride. Because the system requires anhydrous conditions in this production process, the nitrogen source is generally high-purity liquid nitrogen, which has high procurement costs. The traditional exhaust gas treatment method uses three-stage falling film absorption, water absorption, and alkali absorption to capture the acidic gases in the exhaust gas. After the nitrogen is treated and qualified, it is discharged into the atmosphere, generating a large amount of mixed acid and exhaust gas absorption wastewater.

[0004] Traditional treatment methods involve large amounts of hydrogen fluoride being carried away by nitrogen gas for tail gas absorption and treatment, making it impossible to recover hydrogen fluoride and hydrogen chloride through condensation, resulting in serious waste of raw and auxiliary materials and high production costs. Using water to absorb hydrogen fluoride and hydrogen chloride requires equipment materials with high corrosion resistance after absorption, and generates a large amount of mixed acid, which has limitations in treatment and puts enterprises under great environmental pressure. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a device for separating and recovering hydrogen fluoride, hydrogen chloride, and nitrogen in a fluorinated phosphate system. This solves the problems of large quantities of hydrogen fluoride being carried away by nitrogen for tail gas absorption and treatment, the inability to recover hydrogen fluoride and hydrogen chloride through condensation, resulting in significant waste of raw materials and high production costs; the use of water to absorb hydrogen fluoride and hydrogen chloride, which places high demands on the corrosion resistance of the equipment materials; the generation of large quantities of mixed acid, which has limitations in treatment, and the significant environmental pressure faced by enterprises.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a fluorinated phosphate system for the separation and recovery of hydrogen fluoride, hydrogen chloride, and nitrogen, comprising a compressor, a filter, an adsorption tower, a nitrogen buffer tank, a condenser, a gas-liquid separator, and a falling film absorber. The output end of the compressor is connected to the filter, the output end of the filter is connected to the adsorption tower, the output end of the adsorption tower is connected to the condenser and the nitrogen buffer tank, the output end of the condenser is connected to the gas-liquid separator, and the output end of the gas-liquid separator is connected to the falling film absorber.

[0007] Preferably, the output end of the falling film absorber is connected to a ventilator.

[0008] Preferably, a method of using a hydrogen fluoride, hydrogen chloride, and nitrogen separation and recovery device for a fluorinated phosphate system includes the following steps:

[0009] Step 1: The exhaust gas is pressurized to 0.6-1.0MPa by a compressor. The pressurized exhaust gas then passes through a filter with a filtration accuracy of 0.01μm-10μm to ensure that the compressed exhaust gas is free of oil.

[0010] Step 2: The exhaust gas from Step 1 is adsorbed through an adsorption tower. Small molecule gases such as hydrogen chloride and hydrogen fluoride are adsorbed by the adsorbent, while large molecule nitrogen is discharged from the outlet of the adsorption tower through the adsorbent. The purified nitrogen has a purity of over 99% and is sent to various parts of the workshop for use through a buffer tank.

[0011] Step 3: Multiple adsorption towers are set up and switched by regulating valves. After switching, the small molecule gases such as hydrogen chloride and hydrogen fluoride adsorbed in the adsorbent are released by opening the exhaust valve. After depressurization, the exhaust valve is closed and the adsorption tower is used as a backup tower waiting to be switched.

[0012] Step four: The depressurized gas containing hydrogen fluoride and hydrogen chloride released in step three is cooled to below 20°C through a heat exchanger, and the hydrogen fluoride gas is condensed into a liquid state.

[0013] Step 5: The hydrogen chloride gas containing liquid hydrogen fluoride from Step 4 is separated into liquid and gas in a gas-liquid separator to separate the hydrogen fluoride and hydrogen chloride. The liquid hydrogen fluoride is returned to the production process as a raw material and is recycled as a solvent.

[0014] Step six: The hydrogen chloride separated in step five is absorbed by a falling film absorber to form high-quality hydrochloric acid for sale.

[0015] Preferably, in step one, the compressor is preferably an oil-free compressor, and the exhaust gas is pressurized to 0.6-1.0 MPa by the compressor.

[0016] Preferably, in step one, the filter is a Class C filter, a Class A filter, an activated carbon filter, or one or more combinations of devices or equipment that have the same effect.

[0017] Preferably, in step two, the adsorption tower consists of one or more adsorption towers, and more preferably multiple adsorption towers.

[0018] Preferably, the condenser is used to condense and liquefy the desorbed hydrogen fluoride and hydrogen chloride mixture into hydrogen fluoride in the mixture.

[0019] Preferably, in step five, the gas-liquid separator is used to separate the condensed hydrogen fluoride from gaseous hydrogen chloride, and the interior of the gas-liquid separator preferably has a demisting mesh to improve the gas-liquid separation effect.

[0020] Preferably, in step six, the falling film absorber is used to convert the separated hydrogen chloride into easily storable hydrochloric acid.

[0021] Working principle: By using a novel adsorption tower to separate exhaust gas, this process is of great significance in terms of safety, environmental protection, and economy. It can thoroughly separate substances such as hydrogen fluoride, hydrogen chloride, and nitrogen. Hydrogen fluoride and nitrogen are returned to the system for reuse, while hydrogen chloride is converted into liquid hydrogen chloride and high-quality hydrochloric acid for sale. This process achieves full and rational utilization of resources, effectively reduces the amount of waste acid generated, and increases the overall economic benefits of the process.

[0022] This invention provides a device for separating and recovering hydrogen fluoride, hydrogen chloride, and nitrogen in a fluorinated phosphate system. It has the following beneficial effects:

[0023] 1. This invention separates, purifies, and reuses hydrogen fluoride and hydrogen chloride in a mixed gas using physical methods, and recovers hydrogen fluoride and nitrogen to reduce operating costs.

[0024] 2. Compared to traditional treatment methods, this invention processes mixed gas without producing mixed acid, and the produced hydrochloric acid meets industrial-grade quality standards. This reduces environmental pressure and operating costs for enterprises, creating value for them. Attached Figure Description

[0025] Figure 1 This is a diagram of the hydrogen fluoride, hydrogen chloride, and nitrogen separation and recovery device of the fluorinated phosphate system of the present invention.

[0026] The components include: 1. Compressor; 2. Filter; 3. Adsorption tower; 4. Condenser; 5. Gas-liquid separator; 6. Falling film absorber; 7. Fan; and 8. Nitrogen buffer tank. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1:

[0029] This invention provides a device for separating and recovering hydrogen fluoride, hydrogen chloride, and nitrogen in a fluorinated phosphate system, comprising a compressor 1, a filter 2, an adsorption tower 3, a nitrogen buffer tank 8, a condenser 4, a gas-liquid separator 5, and a falling film absorber 6. The output end of the compressor 1 is connected to the filter 2, the output end of the filter 2 is connected to the adsorption tower 3, the output end of the adsorption tower 3 is connected to the condenser 4 and the nitrogen buffer tank 8 respectively, the output end of the condenser 4 is connected to the gas-liquid separator 5, and the output end of the gas-liquid separator 5 is connected to the falling film absorber 6.

[0030] The output end of the falling film absorber 6 is connected to the ventilator 7.

[0031] A method for using a hydrogen fluoride, hydrogen chloride, and nitrogen separation and recovery device for a fluorinated phosphate system includes the following steps:

[0032] Step 1: The exhaust gas is pressurized to 0.6-1.0 MPa by compressor 1. The pressurized exhaust gas then passes through filter 2, which has a filtration accuracy of 0.01μm-10μm to ensure that the compressed exhaust gas is free of oil.

[0033] Step 2: The exhaust gas from Step 1 is adsorbed through adsorption tower 3. Small molecule gases such as hydrogen chloride and hydrogen fluoride are adsorbed by the adsorbent, while large molecule nitrogen is discharged from the outlet of adsorption tower 3 through the adsorbent. The purified nitrogen has a purity of over 99% and is sent to various parts of the workshop for use through a buffer tank.

[0034] Step 3: Multiple adsorption towers 3 are set up and switched by regulating valves. After switching, the small molecule gases such as hydrogen chloride and hydrogen fluoride adsorbed in the adsorbent are released by opening the exhaust valve. After depressurization, the exhaust valve is closed and adsorption tower 3 is used as a backup tower waiting to be switched.

[0035] Step four: The depressurized gas containing hydrogen fluoride and hydrogen chloride released in step three is cooled to below 20°C through a heat exchanger, and the hydrogen fluoride gas is condensed into a liquid state.

[0036] Step 5: The hydrogen chloride gas containing liquid hydrogen fluoride from Step 4 is separated into liquid and gas by gas-liquid separation tank 5. The hydrogen fluoride and hydrogen chloride are separated, and the liquid hydrogen fluoride is returned to the production process as raw material and solvent for recycling.

[0037] Step six: The hydrogen chloride separated in step five is absorbed by falling film absorber 6 to form high-quality hydrochloric acid for sale.

[0038] In step one, compressor 1 is preferably an oil-free compressor, and the exhaust gas is pressurized to 0.6-1.0 MPa by the compressor.

[0039] In step one, filter 2 is a C-grade filter, an A-grade filter, an activated carbon filter, or one or more combinations of devices or equipment that have the same effect.

[0040] In step two, the adsorption tower 3 consists of one or more, preferably multiple adsorption towers 3.

[0041] Condenser 4 is used to condense and liquefy the desorbed hydrogen fluoride and hydrogen chloride mixture into hydrogen fluoride in the mixture.

[0042] In step five, the gas-liquid separator 5 is used to separate the condensed hydrogen fluoride from the gaseous hydrogen chloride. The gas-liquid separator 5 preferably has a demisting wire mesh inside to improve the gas-liquid separation effect.

[0043] In step six, the falling film absorber 6 is used to convert the separated hydrogen chloride into hydrochloric acid that is easy to store.

[0044] Example 2:

[0045] The mixed exhaust gas (280g) contained 4% hydrogen fluoride, 17% hydrogen chloride, and 79% nitrogen. After being pressurized to 0.6 MPa by a compressor, it was adsorbed in an adsorption tower, producing 177.2g of nitrogen with a purity of 99.0% and no detectable moisture. The mixed gas discharged from the adsorption tower was cooled to -20°C by a condenser and then separated in a gas-liquid separator. 11.2g of liquid hydrogen fluoride was recovered, and the gas was absorbed by the absorption tower, producing 153.5g of 31% hydrochloric acid.

[0046] Example 3:

[0047] The mixed exhaust gas (280g) contained 4% hydrogen fluoride, 17% hydrogen chloride, and 79% nitrogen. After being pressurized to 0.7MPa by a compressor, it was adsorbed in an adsorption tower, producing 199g of nitrogen with a purity of 99.5% and no detectable moisture. The mixed gas emitted from the adsorption tower was cooled to -20℃ by a condenser and then separated in a gas-liquid separator. 11.2g of liquid hydrogen fluoride was recovered, and the gas was absorbed by the absorption tower, producing 153.5g of 31% hydrochloric acid.

[0048] Example 4:

[0049] The mixed exhaust gas (280g) contained 4% hydrogen fluoride, 17% hydrogen chloride, and 79% nitrogen. After being pressurized to 1.0 MPa by a compressor, it was adsorbed in an adsorption tower, producing 210g of nitrogen with a purity of 99.9% and no detectable moisture. The mixed gas discharged from the adsorption tower was cooled to -20°C by a condenser and then separated in a gas-liquid separator. 11.2g of liquid hydrogen fluoride was recovered, and the gas was absorbed by an absorption tower, producing 153.5g of 31% hydrochloric acid.

[0050] Example 5:

[0051] This invention provides a device for separating and recovering hydrogen fluoride, hydrogen chloride, and nitrogen in a fluorinated phosphate system, comprising a compressor 1, a filter 2, an adsorption tower 3, a nitrogen buffer tank 8, a condenser 4, a gas-liquid separator 5, and a falling film absorber 6. The output end of the compressor 1 is connected to the filter 2, the output end of the filter 2 is connected to the adsorption tower 3, the output end of the adsorption tower 3 is connected to the condenser 4 and the nitrogen buffer tank 8 respectively, the output end of the condenser 4 is connected to the gas-liquid separator 5, and the output end of the gas-liquid separator 5 is connected to the falling film absorber 6.

[0052] The output end of the falling film absorber 6 is connected to the ventilator 7.

[0053] A method for using a hydrogen fluoride, hydrogen chloride, and nitrogen separation and recovery device for a fluorinated phosphate system includes the following steps:

[0054] Step 1: The exhaust gas is pressurized to 0.6-1.0 MPa by compressor 1. The pressurized exhaust gas then passes through filter 2, which has a filtration accuracy of 0.01μm-10μm to ensure that the compressed exhaust gas is free of oil.

[0055] Step 2: The exhaust gas from Step 1 is adsorbed through adsorption tower 3. Small molecule gases such as hydrogen chloride and hydrogen fluoride are adsorbed by the adsorbent, while large molecule nitrogen is discharged from the outlet of adsorption tower 3 through the adsorbent. The purified nitrogen has a purity of over 99% and is sent to various parts of the workshop for use through a buffer tank.

[0056] Step 3: The released depressurized gas containing hydrogen fluoride and hydrogen chloride is cooled to below 20°C through a heat exchanger, and the hydrogen fluoride gas is condensed into a liquid state.

[0057] Step four: The hydrogen chloride gas containing liquid hydrogen fluoride from step three is separated into liquid and gas by gas-liquid separation tank 5. The hydrogen fluoride and hydrogen chloride are separated, and the liquid hydrogen fluoride is returned to the production process as raw material and solvent for recycling.

[0058] Step 5: The hydrogen chloride separated in Step 4 is absorbed by the falling film absorber 6 to form high-quality hydrochloric acid for sale.

[0059] In step one, compressor 1 is preferably an oil-free compressor, and the exhaust gas is pressurized to 0.6-1.0 MPa by the compressor.

[0060] In step one, filter 2 is a C-grade filter, an A-grade filter, an activated carbon filter, or one or more combinations of devices or equipment that have the same effect.

[0061] In step two, the adsorption tower 3 consists of one or more, preferably multiple adsorption towers 3.

[0062] In step four, the gas-liquid separator 5 is used to separate the condensed hydrogen fluoride from the gaseous hydrogen chloride. The gas-liquid separator 5 preferably has a demisting wire mesh inside to improve the gas-liquid separation effect.

[0063] In step five, the falling film absorber 6 is used to convert the separated hydrogen chloride into hydrochloric acid, which is easy to store.

[0064] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery apparatus, characterized in that, It includes compressor (1), filter (2), adsorption tower (3), nitrogen buffer tank (8), condenser (4), gas-liquid separation tank (5) and falling film absorber (6), the output end of the compressor (1) is communicated with filter (2), the output end of the filter (2) is communicated with adsorption tower (3), the output end of the adsorption tower (3) is communicated with condenser (4) and nitrogen buffer tank (8) respectively, the output end of the condenser (4) is communicated with gas-liquid separation tank (5), the output end of the gas-liquid separation tank (5) is communicated with falling film absorber (6), the condenser (4) is used for condensing hydrogen fluoride in hydrogen fluoride, hydrogen chloride mixed gas after desorption, the gas-liquid separation tank (5) is used for separating hydrogen fluoride from gaseous hydrogen chloride after condensation, the inside mist removal screen of the gas-liquid separation tank (5) improves the gas-liquid separation effect, the falling film absorber (6) is used for converting the separated hydrogen chloride into easy-to-store hydrochloric acid; Wherein, the adsorption tower (3) is used for adsorbing small molecule hydrogen fluoride and hydrogen chloride in mixed gas under high pressure, so that macromolecular nitrogen gas passes through and is discharged from the outlet to the nitrogen buffer tank (8); the adsorption tower (3) is also used for releasing the adsorbed hydrogen fluoride and hydrogen chloride mixed gas to the condenser (4) by decompression desorption; The condenser (4) is used for condensing hydrogen fluoride in the desorbed hydrogen fluoride, hydrogen chloride mixed gas into liquid state; The gas-liquid separation tank (5) is used for separating the condensed liquid hydrogen fluoride from gaseous hydrogen chloride; The falling film absorber (6) is used for converting the separated hydrogen chloride into hydrochloric acid.

2. The fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery device according to claim 1, characterized in that: The output end of the falling film absorber (6) is communicated with fan (7).

3. The fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery device according to claim 1, characterized in that: The compressor (1) is an oil-free compressor, and the tail gas is pressurized to 0.6-1.0 MPa by the compressor.

4. The fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery device according to claim 1, characterized in that: The filter (2) is a combination of one or more of C-grade filter, A-grade filter, activated carbon filter or equivalent effect device.

5. The fluorinated phosphate system hydrogen fluoride, hydrogen chloride, nitrogen separation, recovery apparatus according to claim 1, characterized in that: The adsorption tower (3) is composed of multiple.

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