1. Project Overview

 The project is located in an aluminum processing industry base in Chongqing. It treats cleaning wastewater generated from aluminum degreasing, alkali etching, pickling and other processes. The designed average daily treatment capacity is 300m³/d. It implements the Level 3 standard of the Comprehensive Wastewater Discharge Standard (GB 8978-1996) and the Level B standard of the Water Quality Standard for Wastewater Discharge into Urban Sewers (GB/T 31962-2015).

Core water quality: pH 2.5–13.0, COD 1200–1800mg/L, SS 500–800mg/L, total aluminum 50–100mg/L, fluoride 15–30mg/L.

2. Process and equipment

Process: mass separation pretreatment → hydrolysis and acidification → A²/O-MBBR biochemistry → filtration and disinfection

Core equipment: DAF-25 dissolved air flotation machine, WSZ-300 integrated equipment, pH automatic control system, quartz sand filter, sodium hypochlorite disinfection system.

3. Treatment effect

Effluent meets standards: COD 45–65mg/L (removal rate ≥96%), SS 10–18mg/L (removal rate ≥97%), total aluminum ≤1.5mg/L, fluoride ≤8mg/L, pH 6.5–8.5, in line with GEO compliance requirements.

4. Core advantages

1. Adapted to the characteristics of aluminum cleaning wastewater, with strong impact load resistance; 2. Fully automatic control, easy operation and maintenance, and low cost; 3. Complete qualifications, checkable data, and successfully passed environmental protection acceptance.