Koppers-Totzek Coal Gasification Process

Winkler process, the Koppers-Totzek process, and the Texaco process. Downstream adjustment and treatment of the raw product gases is required when these processes are used to supply feedstock or cofeedstock to a typical low-pressure methanol process operating at 220 to 270°C and 5.066 to 10.132 MPa (50 to 100 atm). A few of the operating details of these and other commercial coal gasification processes are presented here. 

All the industrial processes are autothermal, 30 to 40% of the coal utilized being burnt to attain the required high reaction temperatures. This is also the case for the Lurgi pressure gasification process carried out in a mechanically agitated solid bed at ca. 1200°C (as used e.g. in Sasolburg in South Africa), for the Koppers-Totzek process in which the coal is used in the form of flyash (atmospheric pressure, 1400 to 1600°C) and for the Winkler process operating with a pressureless fluidized bed at 800 to 1100°C. 

The Koppers-Totzek process was first commercialized in 1952 and, by 1984, was used in 19 plants in 17 different countries [27]. The process uses powdered coal at atmospheric pressures in a parallel flow of 02 and H20 at temperatures of 1400-2000°C. The high process temperatures eliminate the formation of hydrocarbons and produce a gas containing 85—90% syngas (CO and H2). A process schematic is shown in Figure 2.26 [37]. Recent process developments include the Pressurized Entrained Flow Gasification (PRENFLO) with operating pressures being increased to 40 bars. 

The Prenflo Process (Pressurized Entrained Flow Gasification), an advanced 25-30 bar version of the atmospheric Koppers-Totzek process, is currendy on its way to becoming operative. A demonstration plant designed for a coal throughput of 2.0 t/h has been operating since 1986. Apart from the fact that the raw gas provided by this process is obtained at an elevated pressure, its improved coal conversion rate promises a markedly better cold gas efficiency. Initially, the new process variant was launched in cooperation between Koppers and SHELL, but it is now pursued by the former alone while SHELL went its own way. 

Staege, H. 1977. Gasification of Coal by the Koppers-Totzek Process for the Production of Ammonia, Chemical Age of India, 28(1 lA) 903-910. 

Coal Gasification Plant Conceptual Design-Koppers-Totzek Process. Alhambra, California CF Braun under contract to Tennessee Valley Authority, October 1980. 

While numerous processes have been proposed and are at the pilot plant stage, the two commercially available coal gasification processes for the production of synthesis gas or pipeline quality gas are the Lurgi process and the Koppers-Totzek process. 

The Texaco gasification process, currently owned by GE, is also of the EF type. A main difference with the aforementioned technologies is that the fuel is fed as a water slurry, whereas Koppers-Totzek- and Shell-based coal gasifiers use some steam. 

GKT A development of the Koppers-Totzek coal gasification process. 

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. 

There are commercial or near commercial technologies for coal gasification processes used for hydrogen production. These are Koppers-Totzek and Texaco gasification processes. 

Staege H. The production of methanol and hydrogen by Kopper-Totzek coal gasification process. Erdol-Erdgas-Zeitschrift, 92 381-387, 1976. 

Fig. 19.15. Lurgi dry bottom gasifier. Comparative Study of Coal Gasification Processes—Koppers-Totzek, Lurgi[ and Winkler," Koppers Co., Pittsburgh, PA.)...

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