Operating Experience Using aMDEA~reg; in a Coal-Based Ammonia Plant CO_2 Removal System Originally Designed for Hot Potassium Carbonate

摘要

In the midst of the energy crisis of the late 1970's and early 1980% the Great Plains Synfuels Plant was designed and built to produce synthetic fuels from lignite coal The plant gasifies 18,500 tons of coal per day to produce 160 million standard cubic feet of synthetic natural gas (SNG) daily and a variety of byproducts. This plant is presently owned and operated by Dakota Gasification Company (DGC). In 1994, Dakota Gas purchased a 30-year old, idle, full-scale anhydrous ammonia production facility and relocated it to the Synfuels Plant complex near Beulah, North Dakota. The unit was an existing 1,000 short-ton-per-day (stpd), CF Braun designed plant originally located in Fort Madison, Iowa. The ammonia plant was de-bottlenecked and revamped to 1,200 stpd prior to startup. Part of the revamping effort included changing the CO_2 Removal unit from a CATACARB~® system to BASF's aMDEA~® technology. Fluor was contracted for the redesign of the unit. The ammonia plant has been operating at the Synfuels Plant for the past seven years. This paper describes the engineering challenges involved in converting a CATACARB~® unit to an aMDEA~® unit and discusses the plant's operating experiences with the CO_2 removal system after the solvent swap and modernization in 1997.