Combustion technical issues

While the development of flue gas clean-up processes has been progressing for many years, a satisfactory process is not yet available. Lime/limestone wet flue gas desulfurization (FGD) scrubber is the most widely used process in the utility industry at present, owing to the fact that it is the most technically developed and generally the most economically attractive. In spite of this, it is expensive and accounts for about 25-35% of the capital and operating costs of a power plant. Techniques for the post combustion control of nitrogen oxides emissions have not been developed as extensively as those for control of sulfur dioxide emissions. Several approaches have been proposed. Among these, ammonia-based selective catalytic reduction (SCR) has received the most attention. But, SCR may not be suitable for U.S. coal-fired power plants because of reliability concerns and other unresolved technical issues (1). These include uncertain catalyst life, water disposal requirements, and the effects of ammonia by-products on plant components downstream from the reactor. The sensitivity of SCR processes to the cost of NH3 is also the subject of some concern. 

This is not just a scientific or technical issue but also a social and psychological one. Safety concerns were frequently voiced when new technologies were introduced, like railway and road vehicles with combustion engines. But the... 

For all these phenomena, high-fidelity predictive CFD methods are sought to be applied in connection with experiments as predictive tools. This is true for flow assurance modeling, in particular as to subsea oil production and transport, and in EOR systems, including using steam or Carbone Dioxide injection in wellbores. At the downstream level, say when use is made of the treated gas for energy production, various technical issues still pertain, as in the gas turbine combustion sector, where CFD is also required to optimize fuel injection, atomization and mixing. 

The pot of gold at the end of the rainbow for low-temperature fuel cells is to replace the internal combustion engines in hundreds of millions of cars, and that creates technical, cost, and logistical issues that are unique to pems. For instance, can hydrogen fuel be delivered to millions of pem vehicles safely, conveniently, and... 

One of the primary contents of the Treaties of the European Community (EC) is the elimination of trade barriers for technical equipment. These barriers have been based on different technical standards (and their legislation) in the member states of the EC. Referring to article 100 of the Treaties of the EC, some directives have been issued in order to harmonize the standardization for technical products (explosion protected electrical apparatus and systems, elevators). These directives describe precisely the technical requirements and list the relevant standards, in the field of explosion protection CENELEC Standards exclusively. Directive 82/130/EEC refers to mines endangered by firedamp and/or combustible dusts, and Directive 76/117/EEC covers areas hazardous due to potentially explosive atmospheres. The member states of the EC shall transform these directives into their national legislation within 18 months. 

There are two technically important methods by which extended Si/0 systems can be formed from molecular precursors. The first is by reaction of chlorosilanes with oxygen at high temperatures, while the second is by hydrolysis and condensation reactions of chloro- or alkoxysilanes. Chapters 32 and 33 deal with the structural evolution of siloxane structures in such reactions from an experimental and theoretical viewpoint. M. Binnewies et al. compare the stepwise formation of Si-0 networks from SiCU for both the combustion and hydrolysis reactions. The stability and reactivity of intermediate chlorosiloxanes is an important issue in this work. Both the initial process in the reaction of SiCfi with O2 and the growth of larger siloxane cages are investigated theoretically in the contribution of K. Jug. 

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