Lithium hexafluorophosphate, as one of the core materials of lithium-ion batteries, the quality of the product determines the charging and discharging performance, service life, and safety of lithium-ion batteries. Due to the lack of significant breakthroughs and substantial progress in the research and development of high-purity crystalline lithium hexafluorophosphate in China, manufacturing technology has long been blocked by foreign companies, and the product market has long been monopolized by foreign companies, seriously restricting the development of China's lithium-ion battery industry.

The successful implementation of the high-purity crystal lithium hexafluorophosphate project in the industrial strong foundation engineering indicates that on the one hand, we need to further increase the efforts to transform and upgrade traditional industries. The implementation of this project has a positive demonstration effect on China's traditional chemical industry's path towards refinement and improvement, and the development from raw materials to new materials; On the other hand, we need to further increase the promotion of strong industrial foundations in key areas. The implementation of this project has broken through key manufacturing technologies and long-term foreign monopolies, reducing the price of lithium hexafluorophosphate from 800000 to 1 million yuan per ton to 200000 to 400000 yuan. It has promoted the rapid and healthy development of China's lithium-ion battery industry and is of great significance for vigorously promoting the development of the new energy vehicle industry.

However, due to the toxicity of lithium hexafluorophosphate, strict management is necessary in the production and management process of lithium hexafluorophosphate, and it is more important to choose suitable lithium hexafluorophosphate production equipment

At around 11:40 on December 9, 2020, during the replacement of the filter element in the lithium hexafluorophosphate production workshop of Houcheng Technology (Nantong) Co., Ltd., the residual anhydrous hydrogen fluoride in the filter element splashed onto the workers, causing hydrogen fluoride poisoning and resulting in one death.

The location of the accident was on the fourth floor of lithium hexafluorophosphate production workshop 2. The removed filter F2736D was located between the lithium hexafluorophosphate main reaction kettle R2736D and the crystallization kettle R2741D in the workshop, mainly used for filtering and removing solid impurities.

There are a total of 8 sets of lithium hexafluorophosphate production facilities in the workshop, and 16 filters with similar materials and media to filter F2736D, mainly including F1735A~D, F1736A~D, F2735A~D, and F2736A~D. Filter F2736D is manufactured by Wuxi Huali Petrochemical Engineering Co., Ltd., with a design pressure of 0.5 MPa and a medium of anhydrous hydrogen fluoride, lithium fluoride, and lithium hexafluorophosphate

After expert judgment, the main reason for the accident was that the company's filter type and compressed air blowing scheme had defects, and the blowing time before the filter replacement operation was too short, resulting in a large amount of anhydrous hydrogen fluoride remaining in the filter element; During the dismantling process, the operators adopted unsafe working methods and did not wear effective protective equipment, resulting in the splashing of anhydrous hydrogen fluoride onto the operators and causing accidents.

In order to overcome various problems encountered in traditional lithium hexafluorophosphate crystallization filtration and drying, and to meet the transformation of the chemical industry towards high quality, high added value, multiple varieties, and small batches Wuxi Shuangrui Machinery Co., Ltd. has successfully developed and produced a lithium hexafluorophosphate filtration, washing and drying integrated machine cylinder cone filtration, washing and drying three in one filtration, washing and drying centrifuge

The lithium hexafluorophosphate filtration, washing and drying integrated machine is a cylindrical cone structure, with heating jackets installed on the cylindrical body and lower cone to heat or cool the material. The multifunctional machine is equipped with a hollow shaft and a variable angle and variable lead hollow spiral stirring device inside to stir and lift the material, and push it out during discharge. A conical filtering device with a complex structure is installed inside the lower cone, and there is a specially designed * fast discharge device or * pneumatic discharge ball valve at the bottom of the equipment.

In the reaction stage, the reaction material is added from the top, and the stirring structure of * can achieve very uniform stirring of the material inside the machine. The material is heated or cooled simultaneously through the cylinder jacket, cone jacket, hollow shaft, and hollow spiral blade, allowing the material to fully react inside the machine. In the filtration stage, this machine can filter and dry the material through pressure or vacuum filtration inside the machine, and add washing solution to automatically re slurry and wash the material multiple times inside the machine. After meeting the washing requirements, it can be compressed and dried again. In the drying stage, the cylinder jacket, cone jacket, hollow shaft, and hollow screw simultaneously heat the material and vacuum it at the top to perform vacuum sealed low-temperature drying. After drying, the material is automatically sealed and discharged.

Advantages of lithium hexafluorophosphate filtration, washing and drying integrated machine:

1. System sealing: The lithium hexafluorophosphate filtration, washing, and drying integrated machine is a fully sealed system that can prevent toxic substances from polluting the air and reduce the occurrence of poisoning accidents among operators during production and operation in a sealed system.

2. Recycling: Materials and solvents are almost completely recovered, avoiding waste caused by material omissions and solvent evaporation, which has great economic benefits.

3. Multi functional integrated operation: filtering, washing, and drying are completed in the same device. The container wall is equipped with a heating jacket to enable drying treatment.

4. Continuous operation: Filtering and drying are carried out in a continuous system without the need to process wet filter cake. The dried product can be mechanically transported to weighing, packaging and other sections.

5. Save manpower: A non-technical personnel with simple training can complete the operation. Opening, closing, automatic feeding, and automatic discharging do not require technical personnel to monitor.

6. Cleaning: The lithium hexafluorophosphate filtration, washing, and drying integrated machine has the functions of automatic spraying and stirring. The filter cake can be thoroughly cleaned, thereby reducing the amount of wastewater discharged and lowering the cost of wastewater treatment.

7. Clean production: The lithium hexafluorophosphate filtration, washing, and drying integrated machine system is equipped with a dust collector to collect the dust generated after drying, which can meet the requirements of clean production.

Wuxi Shuangrui Machinery Co., Ltd. has a professional and experienced design and development elite team, as well as an experienced and service-oriented engineering maintenance service team; Technology *, a production and installation technology team that strives for excellence; A rigorous and scientific quality management system. These powerful conditions have achieved favorable timing, location, and personnel for the development of the enterprise, thereby ensuring that the "mechanical equipment" produced has excellent quality. Looking forward to working together with more customers to achieve win-win results