Effect of Coal Briquetting on Overall Plant Costs for a Large Low-Btu Gas Application. Task II Final Topical Report. Addendum

摘要

This report presents the results of a study to determine the technical and economic aspects of coal briquetting, when the coal briquettes are used as feed coal to a coal gasification facility. Gas from the coal gasification facility was used as the fuel source for an iron ore pelletizing facility. The gasifier for this plant was a two-stage, fixed-bed gasifier. The product gas was 20 x 10 exp 9 Btu per day (833.3 x 10 exp 6 Btu/hour), HHV, to be sent to an iron ore pelletizing facility. The product gas was a clean low-Btu gas produced at approximately atmospheric pressure. The evaluations were based on installing the gasifiers at the existing Erie Mining Company iron ore pelletizing plant at Hoyt Lakes, Minnesota. Thus, the designs use existing facilities where possible, and produce or purchase other needs. The briquetting/gasification design presented is technically feasible. The estimated fuel gas price is $10.00 per million Btu with a 12 percent DCF-ROR. The fuel cost is higher than the present price of natural gas at Hoyt Lakes, $3.52 per million Btu, and higher than the $7.70 per million Btu obtainable through substitution of Winkler fluidized-bed gasifiers for the two-stage fixed bed gasifiers. Not included in the study were considerations of intrinsic factors, such as the interruptible nature of natural gas supplies and future changes in the prices of natural gas and coal. 3 references, 16 figures, 16 tables. (ERA citation 08:050480)