A water and effluent audit carried out in a brewery is described, in which the flow volumes of the main effluent streams were monitored over several weeks and samples were periodically collected for analysis, not only from the main outlets but also from individual process units in order to identify the major sources of pollution. Measures to reduce water wastage and effluent output were recommended, including the blending of lauter tun last runnings with the mash liquor for the next brew, the utilization of the overflow from a hot liquor tank for pasteurization (replacing water specially heated for that purpose), the recovery of yeast from the used CIP prewash rinse water from fermenters and yeast storage tanks, the reuse of CIP rinses, and the reuse of pasteurizing water for bottle washing. Plans for an effluent treatment plant were also drawn up on the basis of the audit report. Substantial savings in water costs, external effluent treatment charges, etc., were expected to result from implementation of the recommendations.
Keywords : brewery costs economisation effluent treatment waste water