Thesis (M.Eng.)-- Chulalongkorn University, 2007

Cleaning In Place (CIP), one of cleaning processes which is widely used in most food and beverage industrials, has been applied to clean raw materials and products remained in storage tanks, pipe lines and equipment because the CIP process provides reliable, fast and efficient cleaning without dismantling equipment. Although, the CIP cleaning process have been developed continuously to increase chemical and water saving, the real operations of these processes still have been considered as a large amount consumed water processes. This work studies process behaviors and optimizes to determine optimal draining ratio of the CIP cleaning chemicals in a dairy plant. To achieve these, mathematical models of the CIP process have been developed and data have been gathered from real plant. With these models, simulation study has been carried out to find out the dynamic behavior of the process with respect to the concentrations and contaminations in cleaning chemicals. The optimization problem has been formulated and solved using written programs based on MATLAB application program. According to the microbial data result, the used cleaning detergent, alkaline and acid, can be recycled. In the optimization approach, the optimal draining ratios have been obtained as 4.34% and 1.70% with 2 and 3 cycles/time draining time after 1 week pass for alkaline and acid respectively.