Pyrolysis of Bituminous Coal and Reactivity between Bituminous Coal Chars and Various Reactive Gases

Abstract

The gasification rates and methane formation for raw bituminous coal, demineralized bituminous coal and the coal chars, high in pyrite and sulfur, were investigated in various gases at 700°C and 850°C. Weight loss or methane production during coal pyrolysis up to 1, 000°C in N₂ was essentially the same over the raw and demineralized bituminous coal and reached a maximum rate in the temperature range of 480∼520°C. Gasification of the char in steam was inhibited by the presence of H₂ and CO. Carbon deposition from CO disproportionation was clearly seen the dry in H₂/CO mixture at both 850 and 700°C. The deposited carbon was seen to be particularly reactive to steam at 850°C and at 700°C. Inorganic constituents present in the raw coal char exhibited negligible catalyst activity for the methanation reaction in the presence of H₂/CO at 850 and 700°C.