Technology, nitrogen oxides emissions

Nitrogen Oxide Emissions. Nitrogen oxide (NO ) emissions from an FCCU regenerator are much less, typically 100 ppm, than SO emissions, and consequently much less attention has been given to the development of technology to reduce FCCU NO emissions. As environmental constraints continue to tighten, this situation is expected to change. 

U.S. Department of Energy, Clean Coal Technology Topical Reports. (1999). Reburmng Technologies for the Control of Nitrogen Oxides Emissions from Coal-Fired Boilers. Report No. 14 (May). Washington, DC U.S. 

Catalyst activities, specific, 10 47t Catalyst additives, nitrogen oxide emissions and, 11 719 Catalyst-based diesel particulate filter (CB-DPF) technology, 10 61-62 Catalyst bed(s)... 

C.T. Bowman. Control of Combustion-Generated Nitrogen Oxide Emissions Technology Driven by Regulation. Proc. Combust. Inst., 24 859-878,1992. 

Catalytic combustion is an environmentally-driven, materials-limited technology with the potential to lower nitrogen oxide emissions from natural gas fired turbines consistently to levels well below 10 ppm. Catalytic combustion also has the potential to lower flammability at the lean limit and achieve stable combustion under conditions where lean premixed homogeneous combustion is not possible. Materials limitations [1,2] have impeded the development of commercially successful combustion catalysts, because no catalytic materials can tolerate for long the nearly adiabatic temperatures needed for gas turbine engines and most industrial heating applications. 

The popularity of fluidized bed combustion is due largely to the technology s fuel flexibility and the capability of meeting sulfur dioxide and nitrogen oxide emission requirements without the need for expensive flue-gas treatment. 

Extensive investigations at the Institute for Mechanical Engineering and Vehicle Technology at the University of Applied Science in Trier as well as practical tests showed that soot emissions were lowered by more than 90% upon the application of water-diesel micro emulsions (see Fig. 11.5(a)). Interestingly, the NO -particulate matter trade-off is avoided, i.e. nitrogen oxide emissions are also lowered significantly (Fig. 11.5(b)). The surfactants used for the formation of the microemulsion are oxidised species, which, as already mentioned above, decrease the soot formation further. 

In 2005, the EPA passed the Clean Air Interstate Rule, which requires a 61% cut in nitrogen oxide emissions from power plants by 2015. This level of emissions reduction requires a different technology. Selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) both convert NOx into water (H2O) and nitrogen (N2). SCR is capable of reducing NOx emissions by approximately 90%. SNCR is a simpler and less expensive technology than SCR, but it also provides a lower level of NOx reduction. 

In addition, flue gas desulfurization reduces the output of sulfur dioxide to the atmosphere and low-NOx burners allow coal-fired plants to reduce nitrogen oxide emissions. Both technologies are in wide use. 

TEL. This particular phase of EPA s attempts to control TEL was related to both health hazard issues and issues of fuel economy and to the technological requirements of a growing national auto fleet equipped with catalytic converters. Optimal function in these converters was required to maximize efficiency of controls on the gaseous criteria pollutants such as nitrogen oxides emissions. Public health and safety was therefore not the sole or most critical explicit component of direct gasoline additive control. 

Table 9.3 Conversion efficiencies, capital costs and nitrogen oxide emissions of methane biogas to electricity with different technologies (Willis et al. 2007). ...

PGM catalyst technology can also be appHed to the control of emissions from stationary internal combustion engines and gas turbines. Catalysts have been designed to treat carbon monoxide, unbumed hydrocarbons, and nitrogen oxides in the exhaust, which arise as a result of incomplete combustion. To reduce or prevent the formation of NO in the first place, catalytic combustion technology based on platinum or palladium has been developed, which is particularly suitable for appHcation in gas turbines. Environmental legislation enacted in many parts of the world has promoted, and is expected to continue to promote, the use of PGMs in these appHcations. 

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