How to clean the EDI unit in semiconductor ultra-pure water equipment

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　　1. During cleaning, the fresh water chamber, concentrated water chamber, and electrode water chamber of the EDI system all need to be cleaned. That is, the cleaning solution enters the EDI through the raw water inlet and concentrated water inlet, and returns to the cleaning tank via the \"produced water\" outlet, \"concentrated water outlet\", and \"electrode water outlet\". (Cleaning mode) 2. First step: Acid cleaning – Prepare a 2.0% hydrochloric acid solution in the cleaning tank and circulate it for 30 minutes. 　　Rinsing: After draining the pickling solution from the tank, rinse the water in the tank until it reaches a neutral pH. Then, rinse the inlet and return pipes until the returning water also reaches a neutral pH. 　　Step 2: Disinfection: Prepare a 0.2% H2O2 solution in the water tank (using approximately 10 kg of 25% H2O2), and circulate it for 50 minutes. 　　Rinsing: After draining the disinfectant from the tank, wash the EDI until the return water in the tank has a conductivity of less than 100 μs/cm. 　　Step 3: Alkaline washing: Prepare a solution of 1.2% NaOH + 5.0% NaCl in the water tank, and circulate it for 50 minutes.