IX Regionalna konferencija Industrijska energetika i zaštita životne sredine u zemljama Jugoistočne Evrope (str. 309-319)
АУТОР(И) / AUTHOR(S): Vladimir B. Živković, Miroslav V. Kljajić, Aleksandar D. Milenković, Lazar D. Jeremić
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DOI: 10.46793/IEEP24.309Z
САЖЕТАК / ABSTRACT:
The use of coal, petroleum products, natural gas as well as municipal and industrial waste for energy production in combustion plants causes pollution emitted with flue gases. Nitrogen oxides (NOx), one of the main pollutants, are produced in large quantities, even under optimized combustion conditions. Due to the reaction of nitrogen oxides with other compounds in the atmosphere, ozone can be formed, resulting in the so-called summer smog. Other waste products, such as nitric acid, lead to acid rain and reach water and soil. This results in an increase in nitrates and a negative impact on people, vegetation and animals. Therefore, in most industrialized countries, laws have been passed to limit the emission of nitrogen oxides. At a time when the world is struggling with the preservation of the environment from the problems already mentioned, several methods have been developed to reduce nitrogen oxides at coal-fired thermal power plants, and they are divided into primary and secondary. The injection of ammonia releasing NOx reduction reagents is still a matter of debate after so many years since its first application. Bad application or the application of inadequate technologies to reduce nitrogen oxides leads to various negative side effects that can lead to unstable operation of the boiler and thus the entire unit outage. This paper provides an insight into the precise selection of the technology of secondary methods for the reduction of nitrogen oxides by Selective Non-Catalytic Reduction (SNCR) at boilers of thermal power plant „Nikola Tesla A“, on units A3-A6. A temperature mapping system is provided in the SNCR system itself, and its function is to prevent the injection of reagent into areas of unfavorable temperature. The indication of the temperature mapping system is processed by the control system, so reagent will always be injected only into zones with the required temperature of 880 – 1050°C. By choosing urea as the reagent, it will be possible to achieve a reduction of nitrogen oxides below thelimits prescribed by: the Terms of Reference 170 mg/m³, the Best Available Techniques for the Prevention and Control of Industrial Pollution (BAT) 175 mg/m³, as well as the European Union Directive75/2010/EU and the Regulation on limit values of emissions of polluting materials into the air from combustion plants („Official Gazette of Republic of Serbia“, No. 6/2016 and 67/2021) 200 mg/m³ of dry flue gases at 6% O2.
КЉУЧНЕ РЕЧИ / KEYWORDS:
Selective Non-Catalytic Reduction, SNCR, NOx reduction, Urea solution, Urea, Ammonia, Ammonia solution
ЛИТЕРАТУРА / REFERENCES:
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