GTL Update

Abstract

Abstract Proven world natural gas reserves, which currently exceed 5,000 trillion cubic feet (TCF), have been growing at a faster rate than proven oil reserves. These gas reserves currently represent over 83% of the energy equivalence of proven oil reserves, of which about 75% is considered to be the less desirable heavy crude. In some remote locations, wellhead costs of natural gas have been estimated to be below $0.25/MMBtu, while the cost of reinjecting "associated" gas from crude oil production as an alternative to flaring may greatly exceed its value. About 3,000 TCF of such gas reserves is considered to be "stranded"; i.e., accessible by drilling but located too far from potential markets for economical transportation to those markets. The chemical conversion of methane to liquid fuels and other higher value products or derivatives which may be more cost effective to transport long distances from remote gas sources has therefore attracted renewed interest. Even though Fischer-Tropsch (FT) synthesis is a technically proven gas-to-liquids (GTL) technology, the conversion of natural gas to liquid fuels such as diesel and gasoline as opposed to higher value chemical products such as chemical grade methanol has only relatively recently been perceived to be a potentially viable commercial proposition. Recent advances in FT synthesis technologies, particularly with regard to natural gas reforming and catalytic partial oxidation, coupled with anticipated increased demand for "clean" diesel fuel appear to be enhancing the economic viability of this route to GTL. The focus of this paper is the prospective economics of promising technologies for FT based GTL diesel production.The scope of this paper includes a brief discussion of potentially important new developments which could have a significant impact on GTL process economics.