ENERGY CONSERVATION IN POLYPROPYLENE PLANT

Abstract

This thesis presents a theoretical investigation on fei aspects of energy conservation in an integrated polypropylen plant which includes a propylene recovery unit based on cracke LPG. It mainly includes energy conservation analysis in the depropaniser column and propane-propylene splitter column in the propylene recovery unit as well as in polymerization reactor. For this purpose a specimen polypropylene plant has been considered. In the depropaniser column and propane-propylene splitter column the effect of decrease in condenser duty on the number of trays in the column has been analysed keeping in view the possibility of tray retrofit. It has been found that large decrease in condenser duty can be obtained with only a modest increase in the number of trays. This suggests that changes of 10 or 20% in the number of trays can save sufficient energy to warrant the expense of a retrofit. In the polymerisation reactor also it has been found that by raising the temperature inside the reactor by 5. or 10., the polymer yield per gm of catalyst can be increased significantly without any adverse effect for the high yield and high stereospecific Himont's catalyst system there by saving considerable amount of energy