Industrial gas cooling

At very high combustion temperatures, it is not sufficient that the first blade row alone needs to be cooled. In practice, up to half a dozen rows may be cooled in an industrial gas turbine, if the combustion temperature is high and the allowable blade metal temperature is low. The cooling fractions for each of the cooled rows must be estimated and u.sed in the cycle calculations, which now become complex. 

In common with magnesium and zirconium the metal has little tendency to capture neutrons, and there was promise that a significant industrial use would arise in nuclear engineering, but after extensive trial in gas cooled reactors, its ultimate commercial employment in that context was also deemed inappropriate. 

The ability to cool (and eventually liquefy) gases by adiabatic expansion underlies industrial gas liquefaction processes. Adiabatic cooling of gaseous nozzle-jet expansions is also an important technique in modem molecular beam and mass spectrometric research. Thermodynamicist John Fenn, winner of the 2002 Nobel Prize in Chemistry, pioneered many of the techniques of adiabatic nozzle-beam cooling. 

The generation of HOBr can be effected by the hydrolysis of bromine gas (Br2) or liquid bromine chloride (BrCl), as in the reaction below. This type of HOBr generation requires the use of large gas cylinders and associated equipment, similar to using chlorine. It is only appropriate for large industrial process cooling systems. 

Japanese industries including Toshiba, Mitsubishi Heavy Industries, Fuji Electric, Toyo Tanso, Nuclear Fuel Industries, etc., are developing the HTGR jointly with JAEA. The industrial and public information exchange is supported by the Japan Atomic Industrial Forum (JAIF), the Research Association of High-temperature Gas-cooled Reactor Plant (RAHP), etc. 

Mitenkov, F.M., N.G. Kodochigov, A.V. Vasyaev, et al. (2004), High-temperature Gas-cooled Reactor as Energy Source for Industrial Hydrogen Production , Nuclear Power, Vol. 97, Issue 6, pp. 43-446. 

Industrial S02 oxidation is done in a sequence of 3 to 5 catalyst beds, Figs. 7.6 and 7.7. This section and Fig. 7.8 describe passage of warm feed gas through three catalyst beds with gas cooling between. The sequence is ... 

Fig. 7.6. Schematic of S02 oxidation converter in which three Fig. 7.1 catalyst beds (with gas cooling between) are used to oxidize -98% of feed S02 to S03. Fig. 1.2 shows the inside of an industrial converter - Fig. 7.7, the outside. Hot gas leaving the catalyst beds is cooled by waste heat boilers, steam superheaters, water heaters, heat exchangers etc.

This limitation is overcome industrially by passing 1st catalyst bed exit gas through two or more gas cooling/catalytic oxidation steps - bringing S02 oxidation efficiency up to 98+ %. 

Fig. 13.1. Schematic of 1st and 2nd catalyst beds with gas cooling between. The cooling system cools lsl catalyst bed exit gas in preparation for more catalytic S02 oxidation in a 2nd catalyst bed. Industrial catalyst bed arrangements are discussed in Chapters 7 and 8. Gas cooling is discussed in Chapter 21.

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