Using the Modified Feed Splitting Technique in Optimizing the Energy for the Natural Gas Sweetening unit of the Ilam GasRefinery

The sweetening unit of the Ilam Gas Refinery plays a major role in providing olefin feed, and at thepresent time, the provinces of Ilam, Kermanshah, Hamedan, Kurdistan, and Lorestan in Iran are theconsumers of the gas produced by this refinery. The gas sweetening unit of the Ilam Gas Refinery hasan absorption and distillation column. H۲S and CO۲ are removed by diethanolamine in the absorptioncolumn, and the solvent used is also recovered in the distillation column. The concern is the high energyconsumption of this process, particularly the distillation column. In this paper, a novel technique wasused for heat integration of the distillation column of the gas sweetening unit of the Ilam Gas Refinery,so that the feed entering the distillation column was splitted into two sections prior to feeding.Afterwards, the bottom section was preheated by the bottom product of column and the top section wasprecooled by the distillate product of column. Preheating the bottom section of feed reduced the heatduty of reboiler and precooling the top section of feed reduced the heat duty of condenser. The resultsdemonstrate that the proposed method decreases the energy consumption by ۱۸%.

Keywords:

Natural Gas Sweetening , diethanolamine , Ilam Gas Refinery , Modified Feed Splitting