Decreasing the Inlet Mercaptan to LPG Treatment to Increase the Efficiency of Adsorber section

To purify and eliminate sulfur compounds from LPG molecular in an oil refinery, a molecular sieve is used; however, due to a change in the feed of the refinery, the amount of sulfur compounds which enters the LPG Unit has increased by 20 times. This change has disrupted the output compounds of the molecular sieve. In this study, it is suggested that a pre-wash process using Soda should be carried out prior to the molecular sieve adsorption process, to increase the efficiency of adsorption process by molecular adsorbents. In order to investigate the possibility of using Caustic to pre-wash the LPG Unit input, the piping of Naphtha Merox Unit was investigated; then, using the Promax software, the process was simulated and reviewed. By carefully examining the factors affecting the reactions, it was tried to select the best model and the optimal conditions. Using caustic, the amount of Mercaptan in the LPG was reduced from 1900 ppm to below 130 ppm and, in line with the original design, it entered the adsorption stage without disrupting the adsorbents performance, and the final values of Mercaptan and H2S reached zero.