Tuesday 2nd February 2010
Gas to liquids: Shrinking the hardware brings big benefits
The gas to liquids (GTL) process offers a promising option for producing valuable liquid fuels from gas resources that would otherwise be wasted. These include associated gas (the gas produced along with oil, which is now frequently disposed of by flaring or re-injection into the reservoir) and stranded gas (gas fields where the gas is not present in large enough quantities to warrant conventional recovery). However, current GTL technology is only economically viable for use in large scale plants designed to process at least 300 million standard cubic feet of gas per day (MMSCFD).
A binding memorandum of understanding (MOU) between PTT, the Thai state-owned energy company, and the Oxford Catalysts Group will help to make the GTL process a viable option on a much smaller scale. This would make it feasible to convert stranded and associated gas from individual onshore oil fields on-site.
The GTL process involves two operations: steam methane reforming (SMR), a process used to convert natural gas into a syngas mixture; followed by Fischer-Tropsch (FT) synthesis to convert the syngas into a liquid fuel.
Under the terms of the MOU, PTT will provide funding of US$5 million over 2 years to support the development and commercialisation of the Oxford Catalysts Group's microchannel steam methane reforming (SMR) technology.
Derek Atkinson, Business Development Manager FT at Oxford Catalysts said:
“Microchannel technology provides an efficient way to get the maximum amount of liquids from associated gas at the lowest capital cost. The small size of the reactors allows for truck transportation to onshore oil fields, and the modular nature of the technology makes the reactors straightforward to set up. It also makes it possible to adjust production capacity by simply adding or subtracting modules.”
Dr. Songkiert Tansamrit, Executive Vice President of PTT said:
“Microchannel reactors and enhanced catalysts offer an exciting breakthrough for small to medium scale GTL. We also envision this technology as potentially game-changing for a wide range of existing and novel chemical and renewable energy processes, such as biofuels production.”
| Derek Atkinson, Business Development Director FT, Oxford Catalysts |
+44 1235 841 700 |
| Nina Morgan, science writer for the Oxford Catalysts Group | +44 1608 676 530 ninamorgan@absw.org.uk |
Notes to Editors
Gas to liquids (GTL)
The GTL process involves two operations: steam methane reforming (SMR), followed by Fischer-Tropsch (FT) synthesis. In SMR the methane gas is mixed with steam and passed over a catalyst to produce a 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.
In the FT process, the syngas is converted into paraffinic hydrocarbons over a cobalt catalyst. The range of products that can be produced includes diesel, jet fuel, naphtha and bases for synthetic lubricants. Generally these are of higher quality than those derived by conventional means.
Microchannel reactors
Microchannel reactors are compact reactors that have channels with diameters in the millimetre range. The small diameter channels dissipate heat more quickly than conventional reactors with larger channel diameters in the 2.5 – 10 cm (1 – 4 inch) range so more active catalysts can be used. Mass and heat transfer limitations reduce the efficiency of the large conventional high pressure reactors used for Fischer-Tropsch synthesis. The use of microchannel processing will make it possible to greatly intensify chemical reactions to enable them to occur at rates 10 to 1000 times faster than in conventional systems.
Promising applications for microchannel reactor technology include GTL and the production of next-generation biofuels from a wide variety of waste sources via biomass to liquids (BTL) processes. The Oxford Catalysts Group is currently working with the Portuguese company SGC Energia (SGCE), to demonstrate and commercialise the Oxford Catalysts Group's FT microchannel reactor for the distributed production of biofuels. (See: http://www.alphagalileo.org/ViewItem.aspx?ItemId=62456&CultureCode=en). It is also working with other partners to demonstrate the application of microchannel GTL for use on offshore platforms and floating production, storage and offloading vessels (FPSOs).
Microchannel FT and SMR
Microchannel FT reactors consist of reactor blocks containing thousands of thin process channels filled with FT catalyst, which are interleaved with water-filled coolant channels. As a result they are able to dissipate the heat generated by the exothermic FT reaction more effectively than conventional systems, so more active catalysts can be used.
In microchannel SMR reactors the combustion and steam methane reforming processes take place in adjacent channels. The high heat transfer properties of the microchannels mean that the heat generated by the combustion is more efficiently used to drive the endothermic SMR reaction.
The microchannel reactors developed by Velocys, Inc., use highly efficient proprietary catalysts developed by Oxford Catalysts.
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 90 employees and operates from facilities near Abingdon, Oxfordshire, UK and Columbus, Ohio, US. The company was founded in October 2004 and was admitted to trading on the AIM market of the London Stock Exchange on 26th April 2006, having raised £15m before expenses from a solid base of institutional investors.
Velocys, Inc.
Velocys, Inc. is based in Columbus, Ohio, US and specialises in the design and development of microchannel process technology for the production of synthetic fuels. The company was spun out of Battelle Memorial Institute, Inc., a major not-for-profit science and technology organisation, in 2001. It owns, or has licenses to, the largest microchannel patent portfolio in the world, with over 550 patent filings, and supports a large microchannel development team. Velocys, Inc. was acquired by Oxford Catalysts in 2008.
Oxford Catalysts Ltd
Oxford Catalysts Ltd designs, develops and licences speciality catalysts for the generation of clean fuels from both conventional fossil fuels and certain renewable sources such as biomass. The company focuses on two key platform technologies.
The first is based on a novel class of catalysts made from metal carbides. Aside from their lower cost, these catalysts offer a number of advantages. For example, in some reactions metal loadings can be reduced. In others, the need for precious metal promoters can be eliminated, while still retaining or even exceeding the benefits of traditional catalysts. Applications of these metal-carbide catalysts include hydro-processing and the conversion of natural gas, biogas or coal into sulphur-free diesel.
The second platform is based on a novel a catalyst and fuel combination that produces instant chemical steam at temperatures between 100ºC and 800ºC+ starting from room temperature. Such Instant Steam could have important applications in a broad range of markets, from cleaning and disinfecting, to green energy in the form of motive power or electricity.
PTT
PTT Public Company Limited is the Thai state oil company. It is a fully integrated oil, gas and petrochemical company, with interests exploration and production, transmission, refining, marketing & trading of petroleum and petrochemical products.
