Abstract:
Objective In order to achieve the effective removal of organosulfur from Tahe oil field associated gas, the simulation of methyl mercaptan distribution in products from Tahe oil field associated gas and processes optimization were studied.
Methods Aspen Plus and HYSYS software were used to simulate the distributions of methyl mercaptan in different products including natural gas, liquefied petroleum gas (LPG) and light hydrocarbons. Aiming at the problem of excessive total sulfur content in liquefied gas, the process optimization scheme was proposed and implemented in industrial unit to examine the optimization effect.
Results The enrichment of methyl mercaptan was the main factor causing excessive total sulfur content in LPG products. The simulation results showed that the mass concentration of mercaptan in LPG could be reduced from 470.44 mg/m3 to 240.14 mg/m3 using the combination of strategy 2 and strategy 3, and the total sulfur mass concentration was 272.94 mg/m3 (sulfide content is presented on the basis of elemental sulfur).
Conclusions After modifying the industrial equipment, the total sulfur mass concentration in LPG product can be controlled below 330 mg/m3, which meets the requirement of total sulfur content specified in GB 11174-2011 Liquefied petroleum gases.