Catalytic combustion power generation

Further, the development of miniaturized devices for the generation of power and/ or heat is discussed here as it represents an emerging field of application of catalytic combustion. Due to the presence of the catalytic phase, the microcombustors have the potential to operate at significantly lower temperatures and higher surface-to-volume ratios than non-catalytic microcombustors. This makes them a viable solution for the development of miniaturized power devices as an alternative to batteries. 

Research on the direct conversion of chemical energy to electricity via fuel cells has received considerable attention in the past decades. Fuel cells are indeed attractive alternatives to combustion engines for electrical power generation in transportation applications and also as promising future power sources, especially for mobile and portable applications. Thus, the search for excellent electrocatalysts for the electro-catalytic oxygen reduction and methanol oxidation reactions, which are the two important cathodic and anodic reactions in fuel cells, is intensively pursued by scientists... 

Catalytic Combustion of Nitrogen Bearing Low Heat Value Gaseous Fuels for Power and Heat Generation, ETSU Project Profile 230, Dec 1998. 

The key interplay of reaction kinetics and transport phenomena in a catalytic combustor must be treated using rigorous reactor models. In the next section, we use a simple model to describe the behavior of a catalytic combustor and to interpret the technology breakthroughs that led to the successful implementation of catalytic combustion to reduce NO in power generation. The model will be kept simple, even though its additional complexities are readily incorporated, because our purpose is to show the main characteristics of a catalytic combustor rather than to provide accurate simulations of expected performance. 

Advances in chemical reaction engineering and catalytic materials have allowed catalytic combustion for thermal energy generation to be commercialized in consumer and industrial applications. The development of catalysts coated on one side of a metal substrate, coupled with the use of diffusion barriers, has allowed controlling the combustion temperature to suit diverse applications. Catalytic materials have been developed to remain active for thousands of hours under conditions deemed too severe just a few years ago. We may expect that the need for clean distributed power increases the demand for gas turbines fitted with catalytic combustors and promotes the development of catalytic burners to be used in fuel processors for fuel cell power systems. 

Catalytic combustion is a process in which a combustible compound and oxygen react on the surface of a catalyst, leading to complete oxidation of the compound. This process takes place without a flame and at much lower temperatures than those associated with conventional flame combustion [1, 2], Due partly to the lower operating temperature, catalytic combustion produces lower emissions of nitrogen oxides (NOv) than conventional combustion. Catalytic combustion is now widely used to remove pollutants from exhaust gases, and there is growing interest in applications in power generation, particularly in gas turbine combustors. 

There is increasing interest in the use of gas turbines for power generation while at the same time more stringent regulations on NOy emissions are being implemented in many areas. This situation provides an opportunity for catalytic combustion and has stimulated much research on catalytic combustors in recent years. Because of their potential commercial importance this section will largely focus on gas turbine applications of catalytic combustion. 

CATALYTIC COMBUSTION FOR POLLUTION ABATEMENT AND CLEANER THERMAL POWER GENERATION... 

Furthermore, total oxidation of lean and near-stoichiometric methane/air mixtures has received great interest in the context of catalytically aided combustion of natural gas for power generation (Trimm. 1983 Pfefferle and Pfefferle. 19S7). Here, the catalyst helps avoiding undesired side reactions (such as NO formation) by lowering the necessary reaction temperature and stabilising the reaction against fluctuations in the feed composition. 

The catalytic reduction of nitrogen oxides, NO, that are produced by combustion of fuels at high temperatures (=1800°C during electric power generation) is one of the important environmental catalytic problems. Review the process that uses ammonia or small hydrocarbons as reducing agents, and list the catalysts that are employed [204, 205]. 

Major tasks of the hydrogen energy program in the Russian Federation in which about 20 scientific organisations are involved include research on fuel cells and electrolyzers both with solid polymer electrolyte, on H2 / O2 steam generator (experiments with 20- 100 kW and 10-20 MW thermal power), and on catalytic combustion [83]. 

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