Underground Coal Gasification in the North Muara Tiga Besar Utara Area, East Merapi District, Lahat Regency, South Sumatera

Abstract

The location of research is located in the North Muara Tiga Besar Area, East Merapi Sub-District, Lahat Regency, South Sumatera. The Geological setting of the North Muara Tiga Besar Area in the South Sumatra Basin is included in the Muara Enim Formation the age is Late Miocene.Coal in the Muara Tiga Besar Utara Area, has a calorific value of 5101-6399 Kcal / kg and is rank High in Bituminous Volatile C-High Volatile Bituminous B according to the ASTM classification. Average quality (proximate test) of Muara Enim Formation coal: sulfur 0.3-1.5% (adb); 1.3-2% ash (adb); inherent moisture 10-12% (adb); volatile matter 40.7-43.4% (adb); fixed carbon 44.5-44.9% (adb), total moisture 29.1-29.8% (Ar); relative density 1.29. Tanjung Enim South Sumatera coal average vitrinite content is (91,4% vol.); liptinite (3.9% vol.); inertinite (4,7% vol.). Eachmaceral or group maceralhas different physical and chemical properties. The variation of composition microscopy showed the changes ofplant communities or coal facies leading to varies of coal quality, with a average vitrinite reflectance value 0.47-0.84, generally the coal rank is subbituminous-bituminous Coal gasification is the process of converting coal into synthesis gas. One of the gas produced is a flammable methane gas. The process of coal gasification can be done by drilling at 2 (two) drill holes toward the coal seam which is the target of gasification coal seam at depth more than 100 meter. The first drill to inject oxygen (O₂) is pressurized like air or water, so it will burn in coal layer, while the second drill serves as a production well to drain raw gas to the gasification reactor for binds CO₂ and eventually methane gas (CH₄) will be flowed to a power plant