The primary objectives of this work are to conduct the first pilot-scale field demonstration of a process to capture, purify, and convert coal mine methane (CMM) into commercially significant volumes of liquefied natural gas (LNG); demonstrate the extent of reduction in CMM emissions; and demonstrate the efficiency and economics of producing LNG from CMM.
Appalachian-Pacific Coal Mine Methane Power Co, LLC, Washington, DC 20004
This project was awarded under a National Energy Technology Laboratory (NETL) program focused on developing improved methods for extracting coal mine methane (CMM) gas. The Appalachian-Pacific CMM Power Company LLC (A-P) planned to demonstrate a pilot process to convert coal mine methane from a mine in Mannington, WV into liquefied natural gas (LNG) that could be used to fuel heavy trucks. The liquefaction process originally envisioned was known as TASHER technology. The TASHER process was to be used to cool the methane to cryogenic temperatures to convert it to LNG, which could be used as a substitute for diesel fuel in modified fleet vehicles.
Subsequently the Mannington site became unavailable and Chart Industries sold its TASHER technology rights to Praxair, which shelved further development. Consequently, with DOE approval, A-P modified its project concept to encompass an approach to employ gas conditioning equipment to condition methane from coal mine gas for sale to a nearby natural gas pipeline (until CMM vehicle fuel markets can be developed) and then deploy non-TASHER refrigeration equipment to liquefy the purified and dehydrated CMM stream for use as a vehicle fuel.
This project, if successful, could demonstrate that commercial quantities of methane can be converted to LNG in an environmentally acceptable manner and could help develop regional markets for the sale of LNG as an alternative transportation fuel. These accomplishments could impact the U.S. energy portfolio by helping to demonstrate the viability of tapping into underutilized supplies of natural gas while simultaneously reducing the volume of CMM vented to the atmosphere.
Given the protracted efforts to gain access to CMM gas from the West Elk Mine site, A-P has focused its investigation into alternate field test sites. A-P visited multiple potential sites in the Appalachian basin throughout 2012, and has narrowed potential options to a single preferred site in Washington County, Pennsylvania. Discussions with site operators about gas and land access for project demonstration purposes are ongoing. More detailed technical, economic, and environmental evaluations are planned for this field site in the coming months. If this site is found to be fully technically suitable, and the project demonstration is considered to be economically viable at the site, then A-P will initiate efforts to secure external funding needed to acquire required liquefaction equipment and pay for demonstration operations.