Coal gasification gasifiers

In 1984, the Ube Ammonia Industry Co. began operating the largest Texaco coal gasification complex to date. This faciUty is located in Ube City, Japan, and has a rated gasification capacity of 1500 t/day of coal, and production capacity of 1000 t/day of ammonia. The plant has successfully gasified coals from Canada, AustraUa, South Africa, and China. At the present time the plant uses a mixture of petroleum coke and coal (43). 

When completed in 1996, the Weihe plant will gasify 1500 t/day of coal to produce 300,000 t/yr of ammonia, which will be used to manufacture 520,000 t/yr of urea fertilizer. This project is the eighth Texaco oil or coal gasification plant Hcensed by Chinese industry. 

Partial oxidation of heavy Hquid hydrocarbons requires somewhat simpler environmental controls. The principal source of particulates is carbon, or soot, formed by the high temperature of the oxidation step. The soot is scmbbed from the raw synthesis gas and either recycled back to the gasifier, or recovered as soHd peUetized fuel. Sulfur and condensate treatment is similar in principle to that required for coal gasification, although the amounts of potential poUutants generated are usually less. 

In 1982, Texaco started up a 900 t/d gasifier at Southern California Edison s Cool Water faciUty. This was the first coal gasification plant to operate in an electric utihty environment, providing coal gas as fuel to a GE-frame 7E combustion turbine. The Cool Water gasification plant operated for over... 

Dow Goal Gasification Process. The Dow coal gasification process (Destec) is a two-stage, slurry feed, entrained-flow, slagging gasifier. 

J. A. Lacey and co-workers, "An Update of the BGL Gasifier," Tenth Mnnual EPRJ Conference on Coal Gasification Power Plants, San Francisco, Calif., Oct. 1991. 

The total plant or train main process bottleneck will probably be identified by the licensor, such as the gasifier for a coal gasification train, the main exchanger for a mixed refrigerant LNG plant train, or the cracked gas compressors for an olefin plant. First and foremost, be sure that the licensor has not made the utility area a bottleneck. This can never be allowed since overloaded utilities could repeatedly shut the entire complex down on a crash basis, adversely impacting economics. 

The licensor s basis for sizing has already been discussed and agreed to or changed. For an olefin plant, the number of steam crackers of the licensor s standard size is firm. For a new process, reactor scaleup methods have been agreed to. For a coal gasification plant, gasifier size. 

Coal gasification is fuel flexible so that the process can use the most available feedstock at the best price. Gasifiers have successfully gasified hcar y fuel oil and combinations of oil and waste gas. Other possible gasification feedstock includes petroleum coke, trash, used tires, and sewage sludge. Various combinations of feedstocks and coal have been successfully gasified. 

In this process, coal is first gasified to CO and H2, which then react to form CH4 as follows Coal gasification - CO + 3H2 —> CH4 + H20 (3.7)... 

The Shell process uses partial oxygen gasification. Because insufficient oxygen exists for complete combustion (20-30% of the oxygen required for complete combustion is used), only a fraction of carbon in the coal is oxidized completely to C02. The heat released from this combustion provides most of the energy needed for endothermic coal gasification reactions and raises the gasifier temperature. Some steam is usually added to prevent excessive... 

Several new concepts under development for hydrogen production from coal were also described. The HyPr-RING method combines coal gasification, C02 separation, and water-gas shift reaction in a gasifier to produce hydrogen. 

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