:: Journal of International Environmental Application & Science ::

Year 2008, Volume III (Issue I)

Journal of International Environmental Application and Science , Vol. 3, No. 5 (2008), 43-50


Water and Wastewater Minimization in Dairy Plants using Water Pinch Technology

Sze-Fei Peng1, Mohammed Farid1, Ian Ho1, Khaled A. Mahdi2

1Department of Chemical & Materials Engineering, The University of Auckland, Private Bag 92019, Auckland, New Zealand
2Chemical Engineering Department, Kuwait University, P.O. Box 5969 Safat 13060, Kuwait

Abstract: Application of water pinch technology to a dairy plant resulted in freshwater consumption and wastewater effluent flow rate reduction of 60% and 65% respectively, simply by re-designing the water management system in the existing water treatment facilities. The volumetric flow rate of wastewater effluent to processed milk flow rate ratio significantly dropped from 1:3.2 to approx 1:1.1. The overall operating cost is found comparable as the decrease in river water intake costs are balanced by an increase in operating costs of the utility processes. Should trade waste charges be imposed on the plan, the new water network will show a 39% reduction in effluent discharge costs. In addition, a significant reduction in contaminant loadings in the discharge was reported for the new water network.  
Keywords: Water Pinch, Dairy Processing, Water Minimization, Optimization, Wastewater treatment