Entrained reactor

Fluid-solid systems, especially in situations where the fluid is a gas, are very frequently encountered in various important industrial processes such as packed-bed reactors, moving-bed reactors, fluidized-bed reactors, and entrained reactors. 

Several types of reactors have been proposed such as the liquid entrained reactor(l) and the Trickle bed reactor(2). The authors have been studying a liquid-phase methanol synthesis process in order to develop a new technology as an alternative for a gas-phase process, and reported that a new process employing liquid-liquid separation of the products from the solvent has several advantages in practical methanol synthesis(3). 

Vijayaraghavan, P. Kulik, C.J. Lee, S. Modelling of a liquid entrained reactor for liquid phase methanol synthesis process. Fuel Sci. Technol. Int. 1992, 10 (9), 1501-1521. 

The detailed isomer distribution data of Pichler, Schulz, and Kiihne (16,17) for hydrogenated hydrocarbons from a fixed-bed synthesis on a precipitated cobalt catalyst at atmospheric pressure (Co.-ThOgikieselguhr = 100 18 100) at 190°C and the entrained reactors of Sasol commercial plant in South Africa, using a reduced fused iron catalyst at 22 atm and about 320°C, were used for testing the nine chain-growth schemes in Table I in the range Co-Cg, Before the analyses, the hydrocarbons were hydrogenated under conditions that should only saturate olefins. The... 

Nitrided iron catalysts are like other iron catalysts in sensitivity to poisoning by sulfur compounds and in the relative usage of H and CO, For all iron catalysts water is the main primary product and COp is produced by the water-gas shift, Nitrided iron produces low of wax, and they can be used in fluid-bed/or entrained reactors at temperatures below 260 C, where reactions leading to deterioration of the catalyst are slow. At... 

An important relatively recent achievement is the development of the so-called liquid entrained reactor (LER) for liquid phase methanol synthesis. To assess the performance of these reactors, much simultaneous work has been done on MARs, comparing the performance of the two types of reactors for this reaction. A good discussion of this can be found in a paper by Vijayaraghavan et a. (1993). An equation developed for the overall gas-liquid mass transfer coefficient (see Ko, 1987 Lee et al., 1988 Parameswaran et al., 1991) is... 

Multiphase reaction engineering has developed into a very active field of research, with international symposia held at frequent intervals. We have only considered a few common reactor types currently in use. A few others of potential importance in relatively large volume intermediates production are the gas-liquid-solid fluidized beds, liquid entrained reactors, and rotating drum reactors. 

The techniques actually available for SO2 removal from flue gases may be broadly classified into wet and dry systems. The wet methods employ a slurry or solution of some absorbent for SO2, whereas the dry systems use dry particles of absorbent in such gas-solid contacting devices as fluidized beds, packed beds, and entrainment reactors. It is with these latter methods that we are concerned here, although wet methods appear to be at least as satisfactory as the dry systems. 

An alternative regeneration scheme is that under development by Showa Denko in Japan. A fluidized or entrainment reactor is used to react magnesia with the SO2 in a stack gas at a relatively low temperature (150°C). Partly reacted magnesia is then regenerated in a second reactor heated to about 800°C yielding a gas stream with a sufficiently high SO2 concentration for sulfuric acid manufacture or SO2 liquefaction. 

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