Abstract：A rice straw gasification for methanol production system of annual 50,000 t was investigated. Based on life cycle assessment, environmental and economic analysis of the process were performed. The total environmental cost of the bio-methanol was 284.99 yuan per ton(via methanol), and it was mainly concentrated in methanol production and methanol consumption. The greenhouse effect was the most important impact factor, among the various types environmental cost of the bio-methanol. Environmental cost of rice straw carbon sequestration, in the upstream of production, was -152.79 yuan per ton, so both the greenhouse effect and the overall environmental impact are negative. Through comparison, it was evident that the total cost of the bio-methanol was 76.84 yuan/ton lower than that of coal based methanol.
