Sodium hexafluorophosphate production device capable of realizing multistage reflux of hydrogen fluoride tail gas

Abstract

The utility model provides a sodium hexafluorophosphate production device capable of realizing multistage reflux of hydrogen fluoride tail gas. The sodium hexafluorophosphate production device comprises a reaction kettle, a condenser and a reflux pipe, the reaction kettle is provided with a reaction cavity and a fixed connecting pipe extending into the bottom of the reaction cavity. The number of the condensers is at least two, and the condensers are arranged above the reaction kettle and are arranged at intervals in the vertical direction. The condensers are sequentially connected in series through connecting pipelines, the lowermost condenser is connected with the fixed connecting pipe, and the uppermost condenser is connected with the tail gas treatment module. The multiple backflow pipes are sequentially communicated with the condensers and the fixed connecting pipes. The sodium hexafluorophosphate production device capable of realizing the multistage backflow of the hydrogen fluoride tail gas, provided by the utility model, can be used for cooling the hydrogen fluoride gas in a grading manner, ensuring the cooling effect, enabling the hydrogen fluoride liquid and the hydrogen fluoride gas to flow separately, effectively avoiding the occurrence of air resistance and material flushing, and being high in practicability.

Description

Technical Field

[0001] The utility model belongs to the technical field of sodium hexafluorophosphate preparation, and in particular relates to a sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas. Background Art

[0002] Sodium hexafluorophosphate (NaPF6) is a white powder and is the core electrolyte used in sodium ion battery electrolytes. High-quality electrolytes have a great impact on the energy density, power density, wide electrochemical window, cycle life, and safety performance of sodium batteries. The electrolyte is generally made of high-purity organic solvents, electrolyte sodium salts, necessary additives and other raw materials, prepared under certain conditions and in a certain proportion. With the improvement of various performance requirements of sodium batteries and further promotion and application, the market demand for sodium hexafluorophosphate in sodium ion battery electrolytes has shown a rapid growth trend, which has attracted many manufacturers to actively deploy. Therefore, reducing the production cost of sodium hexafluorophosphate and improving the market competitiveness of sodium hexafluorophosphate products are the current focus of the industry.

[0003] In the prior art, the production of sodium hexafluorophosphate is involved, and hydrogen fluoride is needed. Since sodium hexafluorophosphate has a low solubility in hydrogen fluoride, more excess anhydrous hydrogen fluoride is needed to participate in the reaction during the reaction process, especially when the reaction temperature is increased, the hydrogen fluoride volatilization amount is larger. In this regard, a condenser is usually connected to the reactor, but the condenser is connected to a gas-liquid pipeline shared by the reaction chamber, and gas blockage is very likely to occur in the gas-liquid pipeline during the production process, causing safety hazards such as "rushing material"; in addition, because the condenser is connected to the tail gas treatment module, the "rushing material" phenomenon will also occur, causing the condensed hydrogen fluoride liquid to rush out of the condenser, and these gases with high hydrogen fluoride concentrations enter the tail gas absorption device, causing the tail gas treatment device to be overloaded, and the exhaust gas emission is unqualified, and the "white smoke" phenomenon occurs, causing environmental accidents, and also causing excessive consumption of hydrogen fluoride, increased production costs, unqualified tail gas emissions, and poor practicality. Utility Model Content

[0004] The embodiment of the utility model provides a sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas, aiming to solve the problem of poor practicality of the existing hydrogen fluoride recovery and treatment method in the sodium hexafluorophosphate production process.

[0005] To achieve the above object, the technical solution adopted by the utility model is: to provide a sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas, comprising:

[0006] A reactor having a reaction chamber and a fixed pipe extending into the bottom of the reaction chamber;

[0007] Condensers, at least two of which are arranged above the reactor and spaced apart in the vertical direction; each of the condensers has a heat medium channel, and the heat medium channels of the condensers are connected in series in sequence through connecting pipes; the heat medium channel of the bottom condenser is connected to the top of the reactor through a connecting pipe, and the heat medium channel of the top condenser is connected to the exhaust gas treatment module through a connecting pipe; a spacing space is formed between any two adjacent condensers;

[0008] There are multiple return pipes, one of which connects the heat medium channel in the lowest condenser with the fixed connecting pipe; the other return pipes are respectively arranged in each of the interval spaces, and each return pipe is respectively connected to the heat medium channels in two adjacent condensers.

[0009] In a possible implementation, each of the condensers has a heat medium inlet and a heat medium outlet communicating with the heat medium channel, and the heat medium inlet and the heat medium outlet are both located at the top of the condenser.

[0010] In a possible implementation, the condensers are connected in sequence through the heat medium inlet and the heat medium outlet.

[0011] In a possible implementation, the condenser is a tube sheet structure.

[0012] In a possible implementation, the bottom end of each condenser is provided with a liquid outlet for connecting to the return pipe and communicating with the heat medium channel; the top end of each condenser is provided with a liquid inlet for connecting to the return pipe and communicating with the heat medium channel.

[0013] In a possible implementation manner, each of the reflux pipes has a U-shaped liquid sealing portion.

[0014] In a possible implementation, each of the condensers has a refrigerant channel, and each of the condensers is connected in series via a connecting pipeline.

[0015] In this implementation, each condenser is arranged above the reactor, which can ensure the effective reception of the volatilized hydrogen fluoride gas and the reuse of the hydrogen fluoride gas after cooling. The multiple condensers arranged in series can extend the cooling process of hydrogen fluoride, and cool the hydrogen fluoride gas in stages to ensure the cooling effect and reduce the amount of hydrogen fluoride entering the tail gas treatment module, which is highly practical. The multiple reflux pipes arranged can ensure that the hydrogen fluoride liquid formed in each condenser is refluxed to the fixed pipe in each condenser in turn, and then enters the reaction chamber, and the reflux pipe and the connecting pipeline connected to the reactor can ensure that the hydrogen fluoride liquid and the hydrogen fluoride gas flow separately, thereby effectively avoiding the occurrence of gas blockage and material impact, which is highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of a sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas provided in an embodiment of the utility model (two condensers are provided);

[0017] Figure 2 for Figure 1 An enlarged structural schematic diagram of point A of a sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas provided in an embodiment (the cylinder part of one condenser is a cross-section view);

[0018] Description of reference numerals:

[0019] 10. Reactor; 11. Fixed pipe;

[0020] 20. Condenser; 21. Heat medium channel; 22. Heat medium inlet; 23. Heat medium outlet; 24. Liquid outlet; 25. Liquid inlet; 26. Refrigerant inlet; 27. Refrigerant outlet;

[0021] 30. Reflux pipe; 31. U-shaped liquid sealing part. DETAILED DESCRIPTION

[0022] 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 in conjunction with 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 used to limit the present invention.

[0023] Please also read Figure 1 and Figure 2 Now, the sodium hexafluorophosphate production device provided by the utility model which can realize multi-stage reflux of hydrogen fluoride tail gas is described.

[0024] The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas comprises a reactor 10, a condenser 20 and a reflux pipe 30. The reactor 10 has a reaction chamber and a fixed pipe 11 extending into the bottom of the reaction chamber. At least two condensers 20 are provided, each condenser 20 is arranged above the reactor 10, and is arranged at intervals in the vertical direction. Each condenser 20 has a heat medium channel 21, and each condenser 20 connects each heat medium channel 21 in series in sequence through a connecting pipeline. The bottom condenser 20 connects the heat medium channel 21 with the top of the reactor 10 through a connecting pipeline, and the top condenser 20 connects the heat medium channel 21 with the tail gas treatment module through a connecting pipeline. An interval space is formed between any two adjacent condensers 20. There are multiple reflux pipes 30, one of which connects the heat medium channel 21 in the bottom condenser 20 with the fixed pipe 11. Other return pipes 30 are respectively arranged in each partition space, and each return pipe 30 is respectively communicated with the heat medium channels 21 in two adjacent condensers 20 .

[0025] The sodium hexafluorophosphate production device that can realize multi-stage reflux of hydrogen fluoride tail gas provided in the present embodiment, compared with the prior art, each condenser 20 is arranged above the reactor 10, which can ensure that the volatilized hydrogen fluoride gas is effectively received, and the hydrogen fluoride gas is cooled and reused. And multiple condensers 20 arranged in series can extend the cooling stroke of hydrogen fluoride, and at the same time, the hydrogen fluoride gas is cooled in stages to ensure the cooling effect, reduce the amount of hydrogen fluoride entering the tail gas treatment module, and have strong practicality. The multiple reflux pipes 30 provided can ensure that the hydrogen fluoride liquid formed in each condenser 20 is refluxed to the fixed pipe 11 in each condenser 20 in turn, and then enters the reaction chamber, and the reflux pipe 30 provided and the connecting pipeline connected to the reactor 10 can ensure that the hydrogen fluoride liquid and the hydrogen fluoride gas flow separately, and then can effectively avoid the occurrence of gas blockage and material impact, and have strong practicality.

[0026] In some embodiments, the condenser 20 may be configured as follows: Figure 2 See the structure shown. Figure 2 Each condenser 20 has a heat medium inlet 22 and a heat medium outlet 23 connected to the heat medium channel 21 , and the heat medium inlet 22 and the heat medium outlet 23 are both located at the top of the condenser 20 .

[0027] The heat medium inlet 22 and the heat medium outlet 23 are both arranged at the top of the condenser 20, which can prevent the hydrogen fluoride gas from contacting the liquefied hydrogen fluoride liquid at the bottom of the heat medium channel 21, thereby preventing the hydrogen fluoride gas from being disturbed or carrying out the hydrogen fluoride liquid, thereby ensuring the separate flow of the hydrogen fluoride gas phase and the liquid phase, with a simple structure and strong practicality.

[0028] In some embodiments, the condenser 20 may be configured as follows: Figure 2 See the structure shown. Figure 2Each condenser 20 is connected in sequence through a heat medium inlet 22 and a heat medium outlet 23. This structure can increase the cooling range of the hydrogen fluoride gas, thereby effectively cooling the hydrogen fluoride gas, reducing the amount of hydrogen fluoride entering the tail gas treatment module, ensuring the recovery and recycling of hydrogen fluoride, and reducing costs.

[0029] In some embodiments, the condenser 20 may be configured as follows: Figure 2 See the structure shown. Figure 2 , the condenser 20 is a tube sheet structure.

[0030] The condenser 20 with a tube-sheet structure is a heat exchange device with a pipe and plate structure, and a plurality of parallel pipes are provided in the heat medium channel 21, and these parallel pipes are connected to the refrigerant cavity at both ends of the condenser 20. The structure of the tube-sheet heat exchange device is prior art and will not be described in detail here.

[0031] In some embodiments, the condenser 20 may be configured as follows: Figure 2 See the structure shown. Figure 2 The bottom of each condenser 20 is provided with a liquid outlet 24 that can be connected to the reflux pipe 30 and communicated with the heat medium channel 21. The top of each condenser 20 is provided with a liquid inlet 25 that can be connected to the reflux pipe 30 and communicated with the heat medium channel 21.

[0032] The liquid outlet 24 provided at the bottom of the condenser 20 can ensure that the cooled hydrogen fluoride liquid flows back to the condenser 20 below or the fixed pipe 11, so as to ensure that the hydrogen fluoride liquid flows back to the reactor 10 again, so that the hydrogen fluoride is reused, which can ensure the reduction of production costs.

[0033] In some embodiments, the return pipe 30 may be Figure 2 See the structure shown. Figure 2 Each reflux pipe 30 has a U-shaped liquid sealing portion 31.

[0034] The U-shaped liquid seal portion 31 can ensure that the heat medium channels 21 in each condenser 20 are separated to prevent the hydrogen fluoride gas from flowing along the reflux pipe 30 , and can ensure the unidirectional flow of the hydrogen fluoride liquid to avoid gas blockage or material impact in the reflux pipe 30 .

[0035] In this embodiment, regarding the reflux pipe 30, two vertical pipes can be provided, and the two vertical pipes are respectively connected to the liquid inlet 25 and the liquid outlet 24 of the two connected condensers 20, or to the liquid outlet 24 of the lowest condenser 20 and the fixed pipe 11. A U-shaped pipe is arranged between the two vertical pipes, and the U-shaped pipe is respectively connected to the two vertical pipes.

[0036] It should be noted that the liquid seal height is comprehensively considered based on the process conditions between the reactor and the condenser, and between the condensers.

[0037] In some embodiments, the condenser 20 may be configured as follows: Figure 2 See the structure shown. Figure 2 Each condenser 20 has a refrigerant channel, and each condenser 20 connects the refrigerant channels in series in sequence through a connecting pipeline.

[0038] The refrigerant can pass through each condenser 20 in sequence through the refrigerant channel to ensure cooling of the hydrogen fluoride gas in the heat medium channel 21. The condensers 20 arranged in series can ensure full utilization of the refrigerant, thereby reducing energy consumption.

[0039] In this embodiment, the condenser 20 has a refrigerant inlet 26 and a refrigerant outlet 27 that connect the refrigerant channels in series. The refrigerant circulation is a prior art and will not be described in detail herein.

[0040] The above description is only a preferred embodiment of the present invention and is 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 protection scope of the present invention.

Claims

1. A sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas, characterized in that: include: A reactor having a reaction chamber and a fixed pipe extending into the bottom of the reaction chamber; Condensers, at least two sets are provided, each of the condensers is arranged above the reactor and spaced apart in the vertical direction; each of the condensers has a heat medium channel, and the heat medium channels of the condensers are connected in series in sequence through connecting pipes; the heat medium channel of the bottom condenser is connected to the top of the reactor through a connecting pipe through a connecting pipe, and the heat medium channel of the top condenser is connected to the exhaust gas treatment module through a connecting pipe; a gas-liquid separation space is formed between any two adjacent condensers; There are multiple return pipes, one of which connects the heat medium channel in the lowest condenser with the fixed connecting pipe; the other return pipes are respectively arranged in each of the interval spaces, and each return pipe is respectively connected to the heat medium channels in two adjacent condensers.

2. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in claim 1, characterized in that: Each of the condensers has a heat medium inlet and a heat medium outlet communicated with the heat medium channel, and the heat medium inlet and the heat medium outlet are both located at the top of the condenser.

3. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in claim 2, characterized in that: The heat medium inlet of each condenser is connected to the heat medium outlet of the next stage condenser in sequence.

4. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in any one of claims 1 to 3, characterized in that: The condenser is a tube-sheet structure.

5. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in claim 1, characterized in that: The bottom end of each condenser is provided with a liquid outlet for connecting to the reflux pipe and communicating with the heat medium channel; the top end of each condenser is provided with a liquid inlet for connecting to the reflux pipe and communicating with the heat medium channel.

6. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in claim 1, characterized in that: Each of the reflux pipes has a U-shaped liquid sealing portion.

7. The sodium hexafluorophosphate production device capable of realizing multi-stage reflux of hydrogen fluoride tail gas as claimed in any one of claims 1 to 3 and 5 to 6, characterized in that: Each of the condensers has a refrigerant channel, and each of the condensers is connected in series via a connecting pipeline.

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