Technologies: Wehrle MBR-HS

The patented Wehrle MBR-HS (also known as the BIOMEMBRAT®) process is suitable for the treatment of highly loaded wastewater. This includes wastewater from the printing, chemical, and pharmaceutical industries, as well as landfill leachate, wastewater from waste oil and special waste disposal, and road tanker cleaning.

Activated sludge from the bioreactor is pumped at a high flow rate through external membranes that are arranged in series. The pressure loss encountered provides the high feed pressure needed for the removal of the treated effluent. Different membranes and module configurations can be selected by our engineers depending on the wastewater being treated. The high cross flow velocity provides the necessary turbulence on the membrane walls.

Wehrle MBR-HS process schematic

Activated sludge concentrations can be maintained at up to 35 g/l should the plant need to be operated at high volumetric loadings on account of high inlet COD loadings or space restrictions.

With such high concentrations of activated sludge, conventional aeration systems may prove inadequate in providing the necessary oxygen for the biomass to treat the wastewater. This problem can be solved by operating the plant with a pure oxygen aeration system and/or a pressurised bioreactor. Overpressure in the bioreactor improves the transfer of oxygen and increases the filtration capacity of the membrane plant.

The Wehrle MBR-HS system is the optimal process for highly loaded wastewater, since it offers, in comparison to other treatment processes, low investment and operating costs. Reduced excess sludge production keeps sludge disposal costs down. The process of aerobically biodegrading contaminants is extremely stable and it is energy efficient in comparison to thermal processes.