Extension-Upgrading Methane Using Ultra-Fast Thermal Swing Adsorption

Tonkovich, Anna Lee

Velocys

关键词: Natural Gas;    Heat Transfer;    Feedback;    Coal Mines;    Pipelines;   

DOI  :  10.2172/883123
RP-ID  :  none
RP-ID  :  FC26-03NT41905
RP-ID  :  883123

美国|英语

来源: UNT Digital Library

【 摘 要 】

The purpose of this project is to develop a cost effective technology for upgrading coal mine methane to natural gas pipeline quality. Nitrogen rejection is the most costly step with conventional technology and emerging competitive technology. Significant cost reductions to this step will allow for the cost effective capture and utilization of this otherwise potent greenhouse gas. The proposed approach is based on the microchannel technology platform that Velocys is developing to commercialize compact and cost efficient chemical processing technology. For this application, ultra fast thermal swing adsorption is enabled by the very high rates of heat transfer enabled by microchannels. Natural gas upgrading systems have six main unit operations: feed compressor, dehydration unit, nitrogen rejection unit, deoxygenator, carbon dioxide scrubber, and a sales compressor. The NRU is the focus of the development program, and a bench-scale demonstration has been initiated. The Velocys NRU system targets producing methane with greater than 96% purity and at least 90% recovery for final commercial operation. A preliminary cost analysis of the methane upgrading system, including the Velocys NRU, suggests that costs below $2.00 per million (MM) BTU methane may be achieved. The cost for a conventional methane upgrading system is well above $2.30 per MM BTU, as benchmarked in an Environmental Protection Agency study. Initial performance results for the Velocys TSA technology were promising. Velocys has also completed initial discussions with several prospective users of the technology and received positive market feedback. Some of the factors that create an attractive opportunity for the technology include the sustained high prices for natural gas, the emerging system of carbon credits, and continued focus on reducing coal mine emissions. While market interest has been confirmed, improvements and optimization are necessary to move the technology to a point that will enable commercial investment in the technology scale-up. In particular, prospective industry collaborators are interested in seeing validation that the technology can meet real-world conditions, including handling impurities, meeting purity and recovery targets (which requires low dead volume), and meeting cost and manufacturability goals.