Energy use, greenhouse gases emission and cost effectiveness of an integrated high– and low–temperature Fisher–Tropsch synthesis plant from a lifecycle viewpoint

Abstract

The lifecycle assessment of energy–greenhouse gases emission–economic performance for single low–temperature Fischer–Tropsch synthesis (LTFTS), high–temperature Fischer–Tropsch synthesis (HTFTS) and HTFTS–LTFTS co-production from coal are investigated and compared to the oil refining process. This covers feedstock supply chain and oil production at the oil refinery and Fischer–Tropsch synthesis (FTS) plants. Results show that the energy input and CO2 emission are mostly from coal mining and washing and oil production at the plant for FTS plants or oil refinery. Cost input is largely from feedstock cost and capital cost for FTS plants, crude oil cost, and transport cost for oil refining process. Compared to oil refinery pathway, FTS to oil currently presents no advantages in the aspect of lifecycle of energy use and greenhouse gases emission. However, the HTFTS-LTFTS demonstrates a favorable economic feasibility especially at a low oil price, indicating that the combined system presents high flexibility and strong market adaptability compared to traditional stand–alone HTFTS, LTFTS and oil refinery plant. Furthermore, in comparison with single HTFTS and LTFTS plants, HTFTS–LTFTS makes a big progress in CO2 emission per unit profit due to its excellent economic benefits. Such an alternative way of coal to oil has an enormous potential to simultaneously satisfy requirements of oil safety and standard of CO2 emission reduction in China.