Feasibility analysis and process simulation of CO2 dehydration using triethylene glycol for CO2 pipeline transportation

The operation of dehydration is very important in the process of gas transportation. This study aims to evaluate the application feasibility of CO₂ dehydration using triethylene glycol, which is also called TEG for short. Aspen Plus software was used to simulate the dehydration process system of CO₂ gas transportation using TEG dehydration. Parameter analysis and process improvement were carried out for the simulation of dehydration process. At first, a sensitivity analysis was conducted to analyze and optimize operating conditions of conventional CO₂-TEG dehydration process system. Subsequently, a recycle unit was introduced into the conventional CO₂-TEG dehydration process system, it can be found that the improved process system with the recycle unit has a higher CO₂ recovery rate which was about 9.8% than the conventional one. Moreover, the improved process system showed excellent operation stability through the comparison of simulation results of several processes with various water contents in their feed gases. Although the energy consumption is increased by about 2%, the improved process was economically and technically feasible for the long-term availability of CO₂ pipeline transportation. The simulated results showed that the improved CO₂-TEG process system has promising application prospects in CO₂ dehydration of CO₂ gas transportation with high stability.