OXFORDPROSPECT - Gas- to-Liquids: it’s time to turn to distributed technologies

The GTL process

Gas-to-Liquids (GTL) is a process used to convert natural gas into high quality liquid fuels that are totally compatible with petroleum based fuels. These fuels can be used in existing engines and infrastructure. The GTL process involves two main operations: production of a synthesis gas (syngas) via processes such as steam methane reforming (SMR) or autothermal reforming (ATR); followed by Fischer-Tropsch (FT) synthesis. The resulting product can either be blended with crude or be upgraded via hydrocracking and fractionation to produce a range of liquid hydrocarbon fuels.

In SMR the methane gas is mixed with steam and passed over a catalyst to produce a synthesis gas (syngas) consisting of hydrogen (H2) and carbon monoxide (CO). The reaction is highly endothermic, so requires the input of heat. This can be generated by the combustion of the excess H2 or other fuel gas. In ATR, oxygen rather than steam is used to produce the syngas.

In the FT process, first developed in Germany in the 1920s and 1930s to produce liquid fuel from coal, syngas is converted into paraffinic hydrocarbons over a cobalt catalyst. The process is highly exothermic, or heat generating. The FT product can be blended with crude oil, or upgraded via hydrocracking to produce a range of products including diesel, jet fuel, naphtha and base oils for synthetic lubricants. Generally these products are of higher quality than those derived by conventional means.

To request a diagram outlining the GTL process, e-mail: info@oxfordcatalysts.com

Distributed modular GTL

GTL plants can be built on a modular basis, located nearer the feedstock resource, by incorporating microchannel reactors and the highly active catalysts optimised for use in them. Distributed GTL plants using this modular approach provide a cost-effective way to take advantage of undervalued resources, such as shale gas and stranded gas located far from existing pipeline infrastructure and markets, and associated gas produced along with oil - resources which would otherwise be wasted. Distributed GTL could produce as much as 25 million barrels per day (bpd) of synthetic fuels annually, worth hundreds of billions of dollars.

Microchannel Fischer-Tropsch (FT) reactors

Microchannel FT reactors are compact reactors containing thousands of channels with characteristic dimensions in the millimetre range. Process channels, filled with catalyst, are interleaved with water-filled coolant channels. The small-sized channels dissipate heat more quickly than conventional reactors with relatively larger tubes in the 2.5 - 10 cm (1 - 4 inch) range. As a result, more active catalysts can be used.

Mass and heat transfer limitations reduce the efficiency of the conventional large FT reactors. The use of microchannel technology makes it possible to overcome these limitations and to intensify the chemical reactions, enabling them to occur at rates 10 to 1000 times faster than in conventional systems.

The Oxford Catalysts Group

Oxford Catalysts Group PLC is a listed public company (LSE: OCG) comprised of two operating subsidiaries - Oxford Catalysts Ltd and Velocys, Inc. The Group has over 80 employees, and operates from facilities near Abingdon, Oxfordshire, UK and Columbus, Ohio, USA. The company was founded in October 2004 and admitted to trading on the AIM market of the London Stock Exchange on 26th April 2006.
The Group’s products (reactors and catalysts) are the basis for modular Gas-to-Liquids (GTL) plants to convert unconventional, remote and problem gas into valuable liquid fuels. These products are marketed under the brand name Velocys. Together with its partners, the Group provides complete modular GTL solutions.

Velocys, Inc.

Velocys, Inc. is based in Columbus, Ohio, USA and specialises in microchannel reactors and process technology for the conversion of low-value natural gas and other resources into clean-burning fuels. The company was spun out of Battelle Memorial Institute, a major not-for-profit science and technology organisation, in 2001. It owns, or has licences to, the largest microchannel patent portfolio in the world, with over 650 patent filings, and supports a large microchannel development team. Velocys, Inc. was acquired by Oxford Catalysts in 2008.

www.velocys.com

Oxford Catalysts Ltd

Oxford Catalysts Ltd provides super-active catalysts for the generation of clean fuels from both low-value fossil resources and renewable sources such as biomass.

Its core technology is a novel class of catalysts made using the organic matrix combustion (OMX) method. Due to tight control of particle size and surface shape, these catalysts offer significantly higher productivity than conventional metal catalysts, allowing products to be made with smaller amounts of catalyst. The catalysts are also more stable and robust to changes in process conditions. These features make them well matched to the Velocys microchannel reactors, especially for the Fischer-Tropsch process.

www.oxfordcatalysts.com