Process Economics Program Report 247A
Advanced Gas-to-Liquid Process
Published: October 2006
Previous PEP reports on gas-to-liquid (GTL) technologies—PEP 135C, Opportunities for Gas-to-Liquid Technologies (February 2000) and PEP 247, Gas to Liquids Update (December 2002)—presented technoeconomic evaluations of the GTL technologies of Sasol, Shell, Syntroleum, ConocoPhillips and British Petroleum. The analyses in those reports were based upon the development status of the technologies in the late 1990s and early 2000s. In the past five or six years, more technological advancements have taken place, which have improved the economic position of GTL products with respect to conventional fuels. Indeed, the high oil prices of recent years have played a very significant part in escalating GTL to prominence.
The areas that received the most attention in the way of studies and R&D work include reactor design and Fischer-Tropsch (F-T) catalysts. Past industrial experience on GTL plants also extended the learning curve. The result of the above is: increased productivity, higher selectivity, and enhanced working life of F-T catalysts; larger sizes and more efficient designs of F-T reactors; higher production-train capacities; more efficient use of process waste-energy; and plant integration capabilities. Based upon recent catalysts properties and F-T reactor design parameters described in patents and other information sources, this new report evaluates the following technologies:
- Syntroleum slurry-reactor based technology. The previous report presented Syntroleum fixed-bed technology that was current in the late 1990s. That technology is no longer in use. This report presents a slurry-reactor based technology, that is especially well suited to offshore barge- or platform-mounted plants (although the technology is good for landbased plants as well).
- Syntroleum slurry-reactor based technology (with power block). This is an enhanced or advanced version of GTL technology in which a (land-based) conceptual model of the Syntroleum GTL plant is integrated with an electric power generation facility.
- ExxonMobil AGC-21 technology. This part contains our interpretation of the design and process economics of the ExxonMobil AGC 21 GTL technology.
Our evaluation indicates that fixed capital cost and production cost for the Syntroleum GTL plant are about 10% lower than those for the ExxonMobil GTL plant. The Syntroleum plant (with power block) has the lowest production cost but the highest product value.