Pressure entrainment

The Texaco gasifier and a similar unit developed by The Dow Chemical Company are pressurized entrained gasifiers. At the top pulverized coal is mixed with reaction gas and is blown down into the gasifier. The reaction products leave from the side, and ash is blown down to a water pool where it is quenched. These units have operated at an Eastman Kodak facUity in Kingsport, Tennessee and at the Coolwater power station in California for an integrated combined cycle power plant. 

PRessurized ENtrained FLOw) gasification technology. Initially developed by Krupp Uhde. Krupp and Shell. They split in 1981 and both developed their own coal gasification process. 

Henrich, E., Weirich, F., Pressurized entrained flow gasifiers for biomass, Environ. Eng. Sci., 2004, 21, 53. 

Figure 1. Schematic diagram of atmospheric pressure entrained flow furnace.

To overcome the disadvantage of atmospheric pressure operation, a version was developed capable of operating at 25-30 bar. This PRENFLOW (pressurized entrained flow) process [561], [562] is being tested in a 48 t/d pilot plant. 

Low Sulfur Fuel by Pressurized Entrainment Carbonization of Coal... 

Precision Combustion, Inc. (PCI), 353 PRENFLO. See pressurized entrained flow... 

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. 

Many similar types of gasifier process effluents and coal tar have been studied from a variety of coal gasifiers. The composition of organic extracts of scrubber water particulate matter from a high pressure, entrained flow gasifier has been reported... 

Based on the promising results a pilot plant covering the complete process chain is about to be constructed in cooperation with Lurgi on the KIT site. The 2-MW (500-kg biomass input capacity) fast pyrolysis plant based on a transported bed (twin screw) reactor was commissioned in 2008. A 5-MW high-pressure entrained flow gasifier equipped with a cooling screen and... 

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. 

The process (Figure 21.21) is based on an air-blown, atmospheric pressure, entrained-bed slagging gasifier and in the process part of the coal char is charged to the combustion section of the gasifier to supply the heat necessary for the endothermic gasification reaction (Patterson, 1976). 

Another actual pyrolysis-based biorefinery concept is the Bioliq process that was developed at the Karlsruhe Institute of Technology (KIT).Bioliq aims at the production of synthetic fuels such as Fischer-Tropsch diesel and chemicals from biomass. Synthesis based on synthesis gas requires pressures of up to 10 MPa. High-pressure entrained flow gasification provides high-quality tar-free syngas with low methane contents. 

The GKT process operates at atmospheric pressure. With the development of pressurized entrained gasifiers (Texaco, Destec and Shell) no more atmospheric pressure gasifiers are likely to be built. Krupp-Koppers, the owners of the GKT gasifier, are developing their own pressurized entrained gasifier, the PRENFLO process. 

Atmospheric Pressure, Entrained Flow Coal Gasification Process Development Unit Program." Palo Alto, California Electric Power Research Institute, February 1983. AP-2846. 

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