Lurgi gas

But, so far as the number of reactors are concerned, I indicated that we have six. That s the maximum number that we require regardless of the quality of the syngas that we process. When we took the Lurgi gas and methanated it, starting with 38% methane already there, we required only four reactors. As a matter of fact, we could have gotten by with three. So it is really a question of how much work you have to do that determines the number of reactors that you would install in the system. 

Fig. 6. Basic schemes for Lurgi gas production, the fundamental technology of which dates back to the era of "artificial" gas. The process shown here (circa early 1970s) permitted selection of various gasifiers and/or changing operating pressures to influence the final crude gas composition, as dictated by the end use and economics. [Lurgi Kt>hie und Mmerabtechnik GmbH. Frankfurt, Germany)...

Lurgi Gas Production Technology The Shell Process Lurgi comp, brochure 189e/6.92/2.20. 

The gas compositions are characterized by low carbon dioxide and high carbon monoxide contents. In the high output run (Test 71) the calorific value of the gas was unaffected, and the organic sulfur content was higher than expected Lurgi gas usually contains less than 10 grains/100 cu. ft. 

The gasification of coal with oxygen and steam under pressure is called the Lurgi process and the gas is called Lurgi gas. As the pressure is increased from 5 to 20 atm, the CH4 and CO2 increases, while the H2 and CO decrease. This gas, once popular as a town gas, is seldom used today. 

Gas comp. Natural gas Producer gas Water gas Coal gas Lurgi gas Landfill gas Bio gas Sewage gas Flame speed Mf (MJ/m ) combustion... 

Since the coal is heated gradually as it passes slowly down through the bed, the Lurgi reactor produces light oils, tars, and phenols, as well as the usual Impurities of hydrogen sulfide and ammonia. A typical Lurgi gas from bituminous coal has the following dry composition ... 

The Lurgi gas cleanup system, shown in Figures 2, 3, and 4, is a good example of the problems involved. Each of the five counter-current exchangers represents a series of complicated, simultaneous equilibrium and heat transfer calculations for a polar mixture, with a three- and possibly four-phase system. (If the solid fines are considered, the system is four, possibly five phases but the solid phase, which most likely stays with the tar, is generally neglected.) Neither the available enthalpy data, nor the available equilibrium correlations, are really adequate for such mixtures, and the problems would be worse if the pressures were higher, as they may be in the future. This is not to say that... 

If air (or oxygen) and steam are both passed through a high-temperature bed of coal or coke these reactions can be balanced, thus controlling the bed temperature and the fusion of the ash. In the higher pressure Lurgi process the gas obtained is high in methane, formed in reactions such as... 

Low Temperature Carbonization. The Lurgi Sptlgas process was developed to carbonize brown coal at relatively low temperatures to produce tars and oils (Fig. 5). A shaft furnace internally heated by process-derived fuel gas (Spblgas) is used. The product can range from a friable coke breeze to hard lump coal depending on the quality of the briquettes used in the feed. The briquettes, made in normal extmsion presses, break down into smaller sizes during carbonization. 

Sasol Fischer-Tropsch Process. 1-Propanol is one of the products from Sasol s Fischer-Tropsch process (7). Coal (qv) is gasified ia Lurgi reactors to produce synthesis gas (H2/CO). After separation from gas Hquids and purification, the synthesis gas is fed iato the Sasol Synthol plant where it is entrained with a powdered iron-based catalyst within the fluid-bed reactors. The exothermic Fischer-Tropsch reaction produces a mixture of hydrocarbons (qv) and oxygenates. The condensation products from the process consist of hydrocarbon Hquids and an aqueous stream that contains a mixture of ketones (qv) and alcohols. The ketones and alcohols are recovered and most of the alcohols are used for the blending of high octane gasoline. Some of the alcohol streams are further purified by distillation to yield pure 1-propanol and ethanol ia a multiunit plant, which has a total capacity of 25,000-30,000 t/yr (see Coal conversion processes, gasification). 

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). 

Cold methanol has proven to be an effective solvent for acid gas removal. Cold methanol is nonselective in terms of hydrogen sulfide and carbon dioxide. The carbon dioxide is released from solution easily by reduction in pressure. Steam heating is required to release the hydrogen sulfide. A cold methanol process is Hcensed by Lurgi as Rectisol and by the Institute Francaise du Petrole (IFP) as IFPEXOL. 

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