Koppers-Totzek process

The feed coal for the process is crushed (so that 70% will pass through a 200-mesh screen), mixed with oxygen and low-pressure steam, and injected into the gasifier through a burner head. The heads are spaced 180° or 90° apart (representing two-headed or four-headed opposed burner arrangements) and are designed such that steam envelopes the flame and protects the reactor walls from excessive heat. 

The reactor typically operates at an exit temperature of about 1480°C (2700°F) and the pressure is maintained just slightly above atmospheric. Only about 85%-90% of the total carbon may be gasified in a single pass through the gasifier because carbon conversion is a function of the reactivity of the coal and approaches 100% for lignite. 

The heat in the reactor causes the formation of slag from mineral ash and this is removed from the bottom of the gasifier through a water seal. Gases and vaporized hydrocarbons produced by the coal at medium temperatures immediately pass through a zone of very high 

In addition, the high operating temperature ensures that the gas product contains no ammonia, tars, phenols, or condensable hydrocarbons. The raw gas can be upgraded to synthesis gas by reacting all or part of the carbon monoxide content with steam to produce additional hydrogen plus carbon dioxide. 

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In the Koppers-Totzek process, the polarized coal is rapidly partially oxidized with oxygen and steam at essentially atmospheric pressure under slogging con-... 

LIGNITE AND BROWN COAL] (Vol 15) Koppers-Totzek process... 

The Entrained system is a high temperature, high reaction rate process in which coal, oxygen (or air) and steam combine rapidly to produce LBG or MBG. The commercial processes aim primarily at the use of oxygen. Several developmental processes use oxygen or air. The most widely used commercial process (Koppers-Totzek) is operated at atmospheric pressure. The Texaco partial oxidation process used with oil and gas is under development for use with coal. Shell and Koppers are developing a pressurized version of the current Koppers-Totzek process. The advantages of the entrained... 

Partial Oxidation Koppers-Totzek Process Electrolysis Steam Iron Steam Reforming... 

Staege, Hermann, "The Production Of Intermediate And Final Products In Synthesis Gas Chemistry According To The Koppers-Totzek Process, Using Coal Gas", Chemical Age of India, Volume 29, No. 12-A, December 1978. 

The Koppers-Totzek Process [555]-[560] used in several ammonia plants in China, India, and South Africa, operates practically at atmospheric pressure. Figure 59 is a simplified sketch of the gasifier. 

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. 

CoaI BasedPartial Oxidation Processes Two commercially estabUshed processes utflizing coal feeds are the Lurgi process (32) and the Koppers-Totzek process (33) the process schemes are shown in Figures 6 and 7, respectively. 

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 Koppers-Totzek process (Baughman, 1978 Michaels and Leonard, 1978) (Figure 21.18) is an entrained-solids process which operates at atmospheric pressure. The reactor (Figure 21.19) is a relatively small, cylindrical, refractory-lined coal burner into which coal, oxygen, and steam are charged through at least two burner heads. 

The principal partial oxidation processes are known as the Texaco, Shell, arxi Koppers-Toteek processes. The Koppers-Totzek process is also used for coal and will be described urxier that heading. The Shell and... 

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. 

Coke was used as the main source of hydrogen in the original Haber-Bosch process. Today coal is still being used in some processes, such as the Lurgi process and the Koppers-Totzek process. However, with the discovery of large gas reserves, coal use is rapidly declining. Over 80% of ammonia produced today is obtained by steam-reforming, and about 70% uses natural gas feedstock. 

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

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