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The PTFE (polytetrafluoroethylene) hollow fiber membrane was developed in 2012 by the Dalian Institute of Chemical Physics, Chinese Academy of Sciences. After its first international application in 2018 for the removal of high concentrations of ammonia nitrogen from vanadium extraction wastewater, it was successfully used again for removing high levels of ammonia nitrogen from pesticide wastewater. The PTFE hollow fiber membrane can be backwashed and regenerated, and it is currently operating stably with good performance. 1) Project overview: XXX Pesticide Production Company originally used a PP hollow fiber membrane system for ammonia removal. After one week of trial operation of this system, the PP membranes suffered from irreversible wetting and penetration issues, which necessitated modifications to the ammonia removal system. Following on-site tests and comprehensive comparisons, our company’s PTFE hollow fiber membrane system was ultimately selected for this purpose. 2) Project scale: The scale of the PTFE hollow fiber membrane ammonia removal system for this project is 4 m3/h. 3) Water quality parameters for inlet and outlet water: Table 1: Inlet water quality for the PTFE hollow fiber membrane ammonia removal system. Parameter | Value: Temperature (°C): 40–50; pH value: >11; Surface tension (mN/m): ≥50; Ammonia nitrogen (mg/L): 2000–5000; COD (mg/L): 10000–30000. Table 2: Outlet water quality for the PTFE hollow fiber membrane ammonia removal system. Parameter | Value: Ammonia nitrogen (mg/L): ≤100 (this value meets the requirements for subsequent biochemical treatment; it can be adjusted as needed). 4) Brief description of the process flow: Effluent from ECO advanced oxidation pretreatment → Sand filter → Precision filter → Heat exchanger → Pipeline mixer (alkali addition point) → Bag filter → Raw water buffer tank → Raw water pump → Safety filter → PTFE hollow fiber membrane ammonia removal unit (three stages in series) → Product water buffer tank → Product water pump → Product water tank → Subsequent treatment processes. The wastewater after ECO advanced oxidation pretreatment first passes through sand filters and precision filters to remove suspended solids, after which it enters a heat exchanger to be cooled to 40–50°C; at the same time, alkali is added to raise the pH above 11. The wastewater then goes through bag filters to further remove suspended solids, followed by entry into a raw water buffer tank. From there, it is pumped by a raw water pump to the primary, secondary, and tertiary PTFE hollow fiber membrane ammonia removal units. To protect these PTFE hollow fiber membrane units, a safety filter is installed after the raw water pump. The wastewater whose ammonia nitrogen levels have been reduced to acceptable levels after treatment by the PTFE hollow fiber membrane units enters a product water buffer tank, from where it is pumped by a product water pump to the subsequent treatment stages. 5) The PTFE hollow fiber membrane denitrification system of the auxiliary system requires supporting systems such as an alkali addition system, an acid recycling system, an ammonium salt disposal system, and a cleaning system. Among these, cleaning is a key method to ensure the ammonia removal efficiency and service life of the PTFE hollow fiber membrane ammonia removal device; PTFE hollow fiber membranes can be backwashed and regenerated, offering a long service life. The PTFE hollow fiber membrane ammonia removal system sends the material to the existing evaporation equipment for evaporation and crystallization, resulting in solid ammonium salts that are then sold for resource utilization. 6) Dimensions of the PTFE hollow fiber membrane deamination device: 4400 (length) × 1300 (width) × 2050 (height) mm ； Series: Three-stage series connection ； Quantity: 1 set ； Number of membranes: 8 units per stage ； Membrane external dimensions: 8"×40" ； Membrane material: Outer shell made of PVC-U, end caps made of epoxy resin, membrane fibers made of PTFE hollow fiber membranes.