Designing High Purity Water and Wastewater Treatment for an Electric Vehicle Manufacturing Facility

Available Quantity of Potable Water Average Daily Maximum Daily Supply Supply (MGD) (MGD) Potable Water 2.0 2. Supply Potable Water Quality Water Quality Parameter Units Range/Value Conductivity μS/cm 91.5 pH S.U. 5.6 – 6. Hardness mg/L CaCO3 25. Alkalinity mg/L 20. Chlorides mg/L 6. Free chlorine mg/L 2. Silica or SiO mg/L 13.7 Iron mg/L 0. TOC mg/L 1.4 Pretreat and Electrodeposition (PTED) Contaminants and Treatment Methods Treatment Processes Typically Required PTED Process Types of Contaminants/Characteristics for Discharge  Oil and grease (emulsified)  High pH from potassium hydroxide or other base  Dissolved air flotation or other oil  Phosphates removal technology for emulsified Degrease  Trace metals from etching + corrosion oil products (zinc, trivalent chromium,  Precipitation + clarification for trace aluminum if processing aluminum metals parts)  Biological growth  Residual conversion coating (contains ethanol + other hydrocarbons)  Flotation is not strictly required but  Low pH is recommended  Copper nitrate, manganese nitrate,  Precipitation + clarification for trace Conversion and other nitrates metals Coating  Zinc and fluoride from  Biological treatment may be hexafluorozirconic acid or other required for organics removal, if zirconium chemistry there is a low BOD requirement  Biological growth  Precipitation + clarification for trace  Residual paint in water (hydrocarbons, metals Electro-deposition trace metals)  Biological treatment may be required for organics removal Description Upstream of pre- Manhole # Manhole #2 treatment) Paint shop preYes (pre-treatment) Yes (post-treatment) Yes (post-treatment) treatment Paint shop Yes (pre-treatment) Yes (post-treatment) Yes (post-treatment) electrodeposition End of line leak testing No No Yes Stamping die washing No No No Body shop floor No Yes (post-treatment) Yes (post-treatment) scrubber waste Sanitary No No Yes COD (mg/L) 1400 1300 Hexavalent chromium <0.0050 <0.0050 <0.0050 (mg/L) Oil & Grease – total N/A <5. N/A pH 6.55 7.61 6. Solids – total dissolved 370 810 700 solids (TDS) Solids – total 920 16 87 suspended solids (TSS) Temperature at pH 7.7 7.6 5. Phenolics (mg/L) 0.21 0.08 0. Surfactants – MBAS <0.10 <0.10 0. Ammonia-N (mg/L) 0.2 0.54 Phosphorus – total as P 31 27 16 (mg/L) Total Kjeldahl Nitrogen 17 5.4 77 (TKN) Mercury (mg/L) <0.00020 <0.00020 <0.00020 Arsenic (mg/L) <0.01 0.0011 0.0014 Cadmium(mg/L) <0.001 <0.0010 <0. Chromium(mg/L) 0.089 0.0047 0.0046 Copper(mg/L) 0.043 0.0038 0. Lead(mg/L) 0.013 <0.0010 <0. Molybdenum(mg/L) 0.078 0.011 0.0043 Nickel(mg/L) <0.0050 <0.0050 0.0068 Zinc(mg/L) 4 0.066 0. Design Basis and Criteria- Wastewater Characteristics 25.