fischer Edelstahl GmbH - Wastewater treatment using compact dissolved-air flotation plant - Case Study
fischer Edelstahl GmbH, a company based in Achern in Germany, has a hall for washing machine parts and transport equipment soiled with various substances, including cooling lubricant emulsions.
The assembly cleaning process, which involves a high-pressure cleaner, a part washing machine and floor cleaning machines, produces approximately 3 m³ of rinsing and cleaning wastewater per day.
Once the wastewater has undergone physical pre-treatment it is still contaminated by emulsions and heavy metals to such an extent that the prescribed values for safe discharge into the sewage system cannot be achieved. The Lugan® 1500 emulsion separation plant is used for the physico-chemical treatment of the wastewater, following the metered addition of Envifloc® flocculating and neutralising agent and a small quantity of compressed air. The resulting flotate sludge is separated from the clean water and transferred to a sludge dewatering system. The clean water, which complies with the required limit values (KW < 20 mg/l in accordance with the German Wastewater Ordinance, Annex 49 and with a pH value of 6.5 to 9.5), flows into the sewage system.
The plant was designed in accordance with the following specifications:
- High level of cleaning performance - central waste disposal
- Low investment and operating costs
- Minimum operating and maintenance effort
- Proven and robust plant design
- Wastewater quantity:
- max. 1.5 m³/h
- Fat and mineral oils
- Chemical contamination: Solids, Hydrocarbons max. 1,000 mg/lheavy metals max. 100 mg/l
- Space requirements: 16 m²
- Control system: PLC, process visualisation