Application of non-standard fluorinated lining equipment in refined phosphoric acid projects

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Non-standard fluorinated lining equipment finds wide and critical applications in phosphate refining projects, mainly due to its excellent corrosion resistance, high-temperature tolerance, and wear resistance, which enable it to meet the demanding conditions encountered during phosphate production. The following are its main application scenarios and features: 1. Core application scenario – reaction equipment such as fluorinated-lined reaction vessels, aging tanks, and mixing/oxidation tanks, which are used for chemical reactions in the synthesis and purification of phosphoric acid. Fluorinated coatings (such as PTFE, FEP) can effectively resist the erosion of phosphoric acid and other corrosive substances, ensuring the long-term stable operation of equipment. - Storage and transfer equipment includes steel-lined PTFE storage tanks, pipelines, and expansion joints, etc. For example, a certain group purchased custom fluorinated expansion joints (made of 316L lined with PTFE) for its refined phosphoric acid project; these joints are used to compensate for thermal expansion and contraction of pipes, while also preventing leakage and corrosion of the medium. - Separation and filtration equipment such as fluorinated basket filters and centrifuges are used to remove impurities or solid particles from phosphoric acid. The tetrafluoro lining can resist corrosion from high-concentration acids and extend the service life of the equipment. - Heat exchange equipment: Fluorinated-lined heat exchangers maintain high efficiency in high-temperature and corrosive environments, preventing the efficiency reduction or leakage risks associated with traditional metal materials due to corrosion. 2. Material advantages – Corrosion resistance: PTFE-based materials exhibit exceptional resistance to strong acids (such as phosphoric acid and sulfuric acid), strong bases, and strong oxidizing agents, far exceeding that of stainless steel or high-nickel alloys. - High-temperature resistance: It can operate stably in the range of -30°C to 150°C; some special processing methods (such as fluoroplastic spraying) allow it to withstand even higher temperatures. - Wear and penetration resistance: The lining, formed through molding or spraying processes (with a thickness of typically 5–25 mm), effectively resists erosion and penetration by media, thereby reducing the frequency of maintenance. 3. Design and Considerations - Customization: The equipment structure and lining thickness must be designed based on specific operating conditions (such as temperature, pressure, and medium concentration) to ensure suitability. - Sealing and installation: Fluorocarbon-sealed components such as PTFE bellows should be used at connections like valves and flanges to prevent leaks ； Piping support design should reduce the load on the equipment. - Supplier qualifications: Priority should be given to manufacturers that hold licenses for the manufacture of special equipment (such as pressure vessels) and possess extensive industry experience, to ensure product quality. In summary, non-standard fluorinated lining equipment plays a key role in phosphate purification projects, especially in applications with high corrosivity, high temperatures, and the presence of solid particles. Through proper material selection and customized design, the equipment’s lifespan can be significantly extended, maintenance costs reduced, and production safety and efficiency ensured. In the future, as the new energy and chemical industries develop, the demand for fluorinated lining equipment will continue to increase, and the technology involved will evolve toward higher temperature and wear resistance.