Environmental impact investigation of natural gas refinery process based on LCA CML-IA baseline method

Gas refinery is an important process in point of energy production and economics. The importance of gas refinery and high amounts of inputs and emissions in the processes emphasize the studying the environmental burdens. The environmental impacts of the natural gas refinery process were evaluated in a gate-to-gate life cycle assessment study based on CML-IA baseline model. Eleven environmental indicators of 1-tonne output gas were calculated and then normalized in SimaPro Software. The values of intermediate indicators of abiotic depletion, fossil abiotic depletion, global warming, ozone layer depletion, human ecotoxicity, freshwater ecotoxicity, marine water ecotoxicity, terrestrial ecotoxicity, photochemical oxidation, acidification potential, and eutrophication were 2.25×10-6 kg Sb eq, 140700.40 MJ, 6846.57 kg CO2 eq, 4.30 kg CFC-11 eq ×10-8, 28.34 1,4-DB eq, 0. 13 Kg 1,4-DB eq, 0752.85 kg 1,4-DB eq, 7.91 kg 1,4-DB eq, 0.40 kg C2H4 eq, 10.27 kg SO2 eq, and 2.68 kg PO4 eq, respectively. The greatest indicator was fossil abiotic depletion with a value of 4.47×10-9 and global warming (1.36×10-9). Acidification potential (3.65×10-10), eutrophication (2.03×10-10), and terrestrial ecotoxicity (1.63×10-10) indicators were ranked after those and the ozone layer depletion indicator had the lowest value. The refinery process, electricity, electronics devices, amine, sodium sulfite, steel, and copper inputs were the main factors affected by most of the studied environmental indicators. The life cycle assessment as a reliable method can be applied in gas refinery sector to address, evaluate, and then decrease the environmental burdens.