A feasibility study on ultrafiltration of industrial effluents

Short-term membrane tests were carried out to determine the feasibility of the application of ultrafiltration for the reuse of effluent from industrial treatment plants. Ultrafiltration proved to be a suitable technology for the treatment and reuse of effluent and with dead-end filtration high permeate fluxes were achieved. An adequate cleaning procedure for the membranes is required to maintain constant and high permeate fluxes. The feasibility is partly determined by the suspended solids concentration in the effluent. For the recirculation of effluent with low suspended solid concentrations the operational costs are comparable to or lower than the costs of drinking water and groundwater. If a high temperature of the process water is required and the thermal energy in the effluent can be reused, an additional saving can be obtained in the total costs per cubic metre water. The technical feasibility of the reuse of effluent depends on the type of industry, the wastewater characteristics and the required permeate quality for reuse. The economic feasibility of effluent reuse will be determined by the present water price, trends in the costs of drinking water or abstraction of groundwater and further developments in the costs of membrane technology.