The Feasibility of LNG Production from Iranian Gas Trunk Line for Road Transportation

Population growth and industrial developments lead to an increase in the consumption of fossil fuels as well as air pollution. Since the road transportion is one of the major sources of air pollution, it is necessary to replace diesel fuel with liquified natural gas (LNG). Generally, liquefied natural gas has been transported to the LNG stations using special carriers and is consumed there. In this study, the feasibility of constructing a liquified natural gas unit feeding from the Iranian gas trunk lines was investigated. A modified version of a single mixed refrigerant (SMR) process was chosen for LNG production, and its simulation was done in Aspen HYSYS V8.6. In this simulation, Temperture, pressure, and composition of the produced gas in the South Pars gas Refineries, as well as the standard composition, were used. By comparing the performance of the proposed process with the conventional process, the feasibility of production of LNG from the feeding of gas trunk lines was approved. Simulation results show that it is possible to produce 62.1 to 62.5 tonnes LNG per hour by the consumption of energy in range of 156 to 162 MW, respectively. In these operating conditions, 89.3% of gas feed could be converted to LNG. Moreover, the energy of 310 to 350 kW per tonnes of produced LNG is required in the liquification units. The proposed LNG unit is better to be constructed in the vicinity of the gas trunk lines and close to large cities. By this way, the required fuel for heavy diesel vehicles will be supplied simply.