Study of The Optimization Condition Of Batch Sterilization Using Genetic Algorithm

Abstract

The present work is designed to study the parameters interaction of sterilizationprocesses in batch bioreactors (fermentors of volume 120 liter with medium of 56784 kg).he parameters include the effects of sterilization temperatures (117-126oC), time ofheating, time of holding, and time of cooling on removal of all organisms, and degradationdegree of medium. Direct steam was used for heating at different temperatures rangedfrom 120oC to 180oC. The B.Stearothermophilus was selected as the present contaminants.Another bioreactor of volume (56828) liter was studied at 121oC for the same contaminantand compared with actual data.This study is achieved by designed procedure and simulation program useful forthe optimization of batch sterilization cycle in large-scale fermentors. The method ofoptimization used is Genetic Algorithm (GAs) which uses probability to find the optimumcondition for the sterilization cycle and to find Del factor; which is the reduction value ofinitial to final number of microorganisms, and then evaluate the cost which depend onamount of steam consumed in the sterilization processesGraphical relations was indicated that as fermentor size increase, the time ofheating also increase. For low temperature the time of holding was increased and for hightemperature the time of holding was decreased. Also these relations were investigated thebest conditions between holding time and Del factor for degradation at differenttemperatures.

Keywords

• batch sterilization reactor
• genetic algorithm