Lurgi technology

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. 

The first few commercial coal gasification plants will probably be based on Lurgi technology, and the first of perhaps several Lurgi-type... 

Conventional sulfuric acid plants have traditionally been used to recover sulfur dioxide from smelter gases, but these are inadequate to meet the proposed sulfur dioxide emission standards. Double absorption, which removes sulfur tri-oxide from the partially converted sulfur dioxide gas stream, reduces the sulfur dioxide emission to less than 500 ppm in the undiluted stack gas. Two double absorption plants using Lurgi technology have been operating with copper converter gas since early 1973. In spite of the wide and frequent variations in gas volume and sulfur dioxide concentration, these plants have consistently maintained sulfur dioxide emission levels well below 500 ppm. This paper presents data on the design and operating conditions for these plants. 

The process for treating the baghouse dusts consists of leaching the dusts with a sulphuric acid solution, generating a lead and silver residue as a by-product, which is returned to the lead smelter, and a zinc sulphate solution, that is purified to remove Pb, Fe, Cd and As. Zinc extraction is carried out by a solvent extraction process based on Lurgi technology. The zinc-rich solution obtained in the solvent extraction plant is sent to the electrolytic zinc plant for zinc recovery and an ammonium sulphate and chloride salt is obtained fix>m the raffinate for agricultural applications. The plant has a capacity of 5,000 totmes Zn/year. 

Supp. E., Technology of Lurgi s Low Pressure Methanol Process, Chem. Tech., 3 430, 1973. 

The means by which synthetic gaseous fuels could be produced from a variety of biomass sources are variable and many of the known gasification technologies can be appHed to the problem (70,71,76—82). For example, the Lurgi circulatory fluidized-bed gasifier is available for the production of gaseous products from biomass feedstocks as well as from coal (83,84). 

E. Supp and A. T. Weschler, "Conversion of Ammonia Plants to Methanol Production using Lurgi s Combined Reforming Technology", HTChE 1992 SpringMeeting, New Orleans. 

Combustion of Sulfur. For most chemical process appHcations requiring sulfur dioxide gas or sulfurous acid, sulfur dioxide is prepared by the burning of sulfur or pyrite [1309-36-0], FeS2. A variety of sulfur and pyrite burners have been developed for sulfuric acid and for the pulp (qv) and paper (qv) iadustries, which produce and immediately consume about 90% of the captive sulfur dioxide produced ia the United States. Information on the European sulfur-to-sulfuric acid technology (with emphasis on Lurgi) is available (255). 

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. 

Geminox A direct process for converting butane to 1,4-butanediol. The butane is first oxidized in the gas phase to maleic anhydride, using BP s fluidized bed technology. The maleic anhydride is scrubbed with water and then catalytically dehydrogenated to butanediol. Developed in 1994 by BP Chemicals and Lurgi. Modifications of the process can be used to make tetrahydrofiuan and y-butyrolactone. The first plant will probably be built on BP s site at Lima, OH, for completion in 2000. 

There are only three types of processes using moving-bed gasifiers (BGL, BHEL, Lurgi) developed at industrial scale. They are the most mature technologies of the three types of... 

Gasifier technology Sasol/Lurgi Texaco/GE Energyf BGL) E-Gas/ConocoPhillips Shell/Uhde ... 

The elemental sulfur is removed by conventional technology. The gases are purified by the Lurgi Rectisol process which uses a low temperature methanol wash to remove H2S, COS and CO2. The acid gas stream is then passed to a Stretford unit which is preferred to the Claus unit because of the high percentage of carbon dioxide in the stream. Sulfur in the stack gas would be removed by conventional flue gas desulfurization techniques and the sulfur would then remain as sulphite sludge and not be recovered as elemental sulfur. 

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