Re-use of biologically treated wastewater of a brewery.

Despite excessive rainfalls, Flanders is dealing with a water deficiency. A rational use of water is a necessity. Apart from the prevention principle, the re-use of biologically treated wastewater (bio-effluent) is increasingly considered. From earlier research it is known that reverse osmosis (RO) is necessary for the elimination of salts and low molecular compounds from the bio-effluent. A thorough pretreatment is necessary to remove drastically the suspended solids, which are harmful to the reverse osmosis modules. This case study describes the experiments performed by SEGHERSbetter technology for Water N.V. on the treatment of wastewater effluent from a brewery. A comparative study between sand filtration (SF), in-line coagulation with sand filtration and ultrafiltration (UF) as a pretreatment was made. UF proved to be the best pretreatment for RO for the treatment of brewery bio-effluent. Finally, an economic evaluation of the membrane system (UF followed by RO) was made. The calculated total cost for the system is 0.26 Euros per m3 produced water. Investment costs and operation cost are also discussed.