Other Lurgi Plants

The feed stocks include naphtha, natural gas liquids, propane and butane. The cost of SNG gas from these plants is as high as 5 to 6 per Mcf. The investment cost is very low for this type of SNG plant and is on the order of 522 per million Btu per day of capacity at a 50% load factor. This can be compared with the investment cost of high-Btu pipeline-gas-from-coal plants which is now on the order of 12,444 per million Btu per day of capacity based on the Lurgi process and 90% load factor. There are two other SNG plants in the planning or construction stage. 

The chemical complex includes the methanol plant, methyl acetate plant, and acetic anhydride plant. The methanol plant uses the Lurgi process for hydrogenation of CO over a copper-based catalyst. The plant is capable of producing 165,000 t/yr of methanol. The methyl acetate plant converts this methanol, purchased methanol, and recovered acetic acid from other Eastman processes into approximately 440,000 t/yr of methyl acetate. 

The success of the Sasol project is attributed to the availabiUty of cheap coal and the rehabiUty of the selected components. Plants using Lurgi or Koppers-Totzek gasifiers for making chemicals are located in AustraUa, Turkey, Greece, India, and Yugoslavia, among other countries. 

Status of Indirect Liquefaction Technology The only commercial indirect coal liquefaction plants for the production of transportation fuels are operated by SASOL in South Africa. Construction of the original plant was begun in 1950, and operations began in 1955. This plant employs both fixed-bed (Arge) and entrained-bed (Synthol) reactors. Two additional plants were later constructed with start-ups in 1980 and 1983. These latter plants employ dry-ash Lurgi Mark IV coal gasifiers and entrained-bed (Synthol) reactors for synthesis gas conversion. These plants currently produce 45 percent of South Africa s transportation fuel requirements, and, in addition, they produce more than 120 other products from coal. 

The chapter by Eisenlohr et al. deals with the results of large scale pilot operations using a newly developed high-nickel catalyst with hot-gas recycle for temperature control. This and other work, conducted by Lurgi Mineraloeltechnik GmbH, with South African Coal and Oil Limited (SASOL), are the bases of the methanation process which Lurgi is proposing for commercial plants. 

Consequently, two semicommercial pilot plants have been operated for 1.5 years. One plant, designed and erected by Lurgi and South African Coal, Oil, and Gas Corp. (SASOL), Sasolburg, South Africa, was operated as a sidestream plant to a commercial Fischer-Tropsch synthesis plant. Synthesis gas is produced in a commercial coal pressure gasification plant which includes Rectisol gas purification and shift conversion so the overall process scheme for producing SNG from coal could be demonstrated successfully. The other plant, a joint effort of Lurgi and El Paso Natural Gas Corp., was operated at the same time at Petrochemie Schwechat, near Vienna, Austria. Since the starting material was synthesis gas produced from naphtha, different reaction conditions from those of the SASOL plant have also been operated successfully. 

And now I would like to comment on how much cost reduction can we really expect from all of this work. Figure 6 shows a breakdown of investment by plant section for a typical Lurgi SNG plant. The information is about three years old from the open literature. As shown, the gasification section accounts for only about 20% of the total plant investment. Other process sections, including shift, methanation, and other process gas account for another 30%, making a total of 50% for the process sections. The utilities add up to 33%, including 11% for the oxygen plant alone. 

So far only the Koppers - Totzek, Texaco and Lurgi gasifiers, and probably the Winkler process in some smaller installations, have been used in ammonia plants, but the successful demonstration of the Shell process in other applications make it a potential candidate for ammonia production, too. Additional processes in different stages of technical development are the HTW and the Dow process. Information on the status and the development in the gasification of coal can be obtained from [541], [545], [548] -[554],... 

In addition, two other major efforts have been announced to develop coal gasification facilities in northwestern New Mexico. These proposed plants would be based on an extension of the Lurgi technology which has been used in Europe for many years. The first is a project proposed by El Paso Natural Gas Co., and the second is a proposal by a consortium composed of Pacific Lighting Service Co., Texas Eastern Transmission Corp., and Utah International, Inc. Each of these projects calls for the construction of one or more gasification plants, each capable of producing about 250 million cubic feet per day, and would utilize some of the extensive coal reserves of the area. 

In the two decades since I.C.I. introduced the low-pressure methanol process others have gained increasing shares of the market. Major competitors include Lurgi, Mitsubishi Gas Chemicals and Haldor Topsoe. All have their own variations of the co-precipitated Cu-ZnO catalysts. Recently, Alberta Gas Chemicals has constructed several 1200 tonne/day plants one at Medicine Hat, Alberta and the other at Taranaki near the Synfuels methanol-to-gasoline plant in New Zealand. The Alberta Gas Chemicals plants use catalysts under licence. 

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