Lurgi coal gasification

Fig. 6. Flow sheet for ammonia production from Lurgi coal gasification.

In Lurgi coal gasification, an example of extremely important treating is in the sulfur removal step ahead of methanation where the catalyst is poisoned by even small traces of any sulfur compound. The sulfur removal step is a relatively high capital and operating cost item. 

Over the past seven years, a number of groups in the U.S. have announced plans for Lurgi coal gasification commercial projects to produce SNG. However, none of these projects has reached the construction stage. The main reasons for the delays have included problems with government approvals and regulations. Difficulties with environmental clearances, the cost and pricing... 

The British Gas/Lurgi Coal Gasification Plant at Westfield, Scotland. 5-54... 

EPRI Studies. The Electric Power Research Institute (EPRI) has sponsored a number of engineering and economic studies of the conventional dry ash Lurgi coal gasification process. Economic and technical analyses have been completed for the following applications ... 

Operation at very low temperatures with very sharp separations results in relatively complex flow schemes. This, combined with the need for low level refrigeration, leads to high plant costs. As a result, most applications of the Rectisol process represent relatively difficult gas treating conditions where other gas treating processes are not suitable for one reason or another. Typical applications are the purification of gas streams in the heavy oil partial oxidation processes of Shell and Texaco and the Lurgi coal gasification process, as used at the Sasol plants in South Africa. 

Many of these steps are made necessary by the presence of naphtha and other troublesome contaminants in the gas stream and are not normally included in plants that treat gas streams derived from sources other than the Lurgi coal gasification process. 

Lurgi coal gasifleadon process A process involving the gasification of coal under pressure with mixtures of steam and oxygen. The reactions produce CO and H,. 

The German Lurgi Company and Linde A. G. developed the Rectisol process to use methanol to sweeten natural gas. Due to the high vapor pressure of methanol this process is usually operated at temperatures of -30 to -100°F. It has been applied to the purification of gas 1 plants and in coal gasification plants, but is not used commonlv natural gas streams. 

Koppers-Totzek A coal gasification process using an entrained bed. The coal is finely ground and injected in a jet of steam and oxygen into a circular vessel maintained at 1,500°C. Reaction is complete within one second. The ash is removed as a molten slag. The process was invented by F. Totzek at Heinrich Koppers, Essen, and further developed by Koppers Company in Louisiana, MO, under contract with the U.S. Bureau of Mines. The first commercial operation was at Oulu, Finland, in 1952 by 1979, 53 units had been built. Most of the plants are operated to produce a hydrogen-rich gas for use in ammonia synthesis. Developed by Lurgi. See also PRENFLO. 

SASOL [Suid-Afrikaans Sintetiese Olie] Not a process but a large coal gasification complex in South Africa, operated by the South African Oil and Gas Corporation. It first operated in 1955 but took several years to be fully commissioned. A Lurgi fixed-bed gasification unit is used for the primary process. Downstream processes include the following ones, described under their respective names Aige, Fischer-Tropsch, Rectisol, Sulfohn, Synthol. 

The system considered here is the Lurgi dry ash coal gasification process as used at SASOL in the Republic of South Africa and proposed for use at the Great Plains gasification project in North Dakota (2). The important steps in the process as far as... 

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