A novel method for heat integration of natural gas sweetening process

The natural gas sweetening unit usually involves an absorption column and a distillation column.The absorption column completely removes H۲S and CO۲ from natural gas, and the distillation columnis used to recover the solvent. The main problem is high energy consumption in the gas sweeteningprocess, particularly in the distillation column, necessitating energy optimization of this process. Anovel method was used in this study for heat integration of the natural gas sweetening process. To thisend, liquid and vapor streams leaving the absorption column entered the top and bottom of thedistillation column, respectively. The feed entering the distillation column was preheated by the bottomproduct. The liquid and vapor streams reduced the cold and hot utilities of the distillation column, andfeed preheating reduced the heat duty of the reboiler. The recycled solvent was then precooled by thesweetened gas. According to the results, the proposed method reduced energy consumption by ۶۷%.

Keywords:

natural gas sweetening , monoethanolamine , heat integration , utility consumption reduction