Metalworking Fluids/Coolant Treatment

Challenge

The UWEG Umweltschutz und Wertstoff-Recycling GmbH & Co KG has a permit for 120.000 Tn for annual wastewater dischare of the CP-plant, 5.800 cleaning tanks per year and 28 employees. Due to the oil content in some hazardous liquid wastes with organic pollutants, the physico-chemical treatment of the wastewater and the ineffectiveness of their oil removal, the oil level has risen above the desired concentration (> 20 mg/l) prior biological treatment. UWEG wanted to reach an oil in water quality prior biological treatment of < 20 mg/l with minimal operating costs (<10%).

Solution

An implementation of a 1 m³/h akvoFloat pilot with chemical pre-treatment step prior to AkvoFloat technology is crucial for a stable operation of the plant in terms of low fouling of the membrane and constant permeate flux.
The feasibility of discharging the treated water directly into the biological treatment will lead to a significant reduction of the overall water disposal costs.

Results

  • High removal efficiency:
    • COD: from 90.000 ppm to 3.000 ppm (> 92 %)
    • Oil: from 400 ppm to < 0.1 ppm (> 99,9 %)
  • High recovery (> 95%)
  • 3 weeks between chemical cleanings
  • High flux (55 lmh)
  • Low pressure drop (0,1- 0,25 bar)