Combustion

Engineering

Oil shale

Organic chemistry

Chemistry

Ecology

Liquid fuel

Environmental science

Greenhouse gas

Coal

Renewable fuels

Waste management

Fossil fuel

Biology

Environmental engineering

Shale oil

Resources Conservation and Recycling

Traditional liquid fuels production is heavily dependent on crude oil. Due to the conflict between liquid fuels demand and shortage of crude oil supply, Chinese government has begun to develop alternative feedstocks. In this paper, we carried out comparative analysis of coal to liquid fuels (CTF) and oil shale to liquid fuels (STF) from the perspectives of life cycle GHG emissions and water consumption. Results show that the life cycle GHG emissions of the CTF and STF routes are 15.54 and 9.82 t CO2-eq/t-fuels, which are greatly higher than that of oil to liquid fuels (OTF) route (6.36 t CO2-eq/t-fuels). The life cycle water consumption of the CTF route is the largest, 12.98 t/t-fuels, followed by the STF route, 7.69 t/t-fuels, and the OTF route 1.18 t/t-fuels. Therefore, taking measures to conduct the reduction of GHG emissions and water consumption is the key for the CTF. Three feasible suggestions are proposed as follows: (1) integrating coal and hydrogen-rich gas to produce liquid fuels; (2) optimizing the heat exchange and water networks; and (3) mobilizing the enthusiasm of reduction of emissions and saving water by implementing carbon tax and raising water price.

Life cycle comparison of greenhouse gas emissions and water consumption for coal and oil shale to liquid fuels