Influence of replacement of steam power plant on combined cycle gas equipment on the sanitary protection zone by noise factor

Abstract

Improving the safety of energy equipment of thermal power plants (TPPs) is an important task. The safety of power equipment is affected by physical influences, the most important of which is noise. Noise is one of the factors determining the size of the sanitary protection zone of thermal power plants. Article analyses the influence of TPP equipment structure on the size of sanitary protection zone (SPZ) by noise factor when replacing the equipment of traditional steam power plants with the equipment of steam and gas plants. Combined cycle gas plants (CCGT) are the most innovative technology in heat and power industry. Currently, most of exhausted steam turbine units (STU) replaced by CCGT. CCGTs are more economical and at the same time have better environmental performance, which consists in both less emission of pollutants and less noise exposure. STU supplied in standard configuration, as their efficiency slightly depends on external conditions. On contrary, the efficiency of CCGT significantly depends on climatic conditions. This dependence necessitates the implementation of individual projects, which allows at design stage of CCGT equipment to provide measures to reduce noise. Main CCGT’s noise sources are air inlet and gas outlet. At design stage, provide reducing sound pressure levels to regulatory values on border of SPZ. Data of calculations showing that increasing of STU power leads to an increase the size of the SPZ. Comparison with the results of calculations on semiempirical model and using computer of SPZ sizes at different type and structure of STU is given. Transition to supercritical steam parameters causes a jump in noise levels. Considered stepwise withdrawal of equipment and its replacement by CCGT. Described a decrease in noise levels at SPZ border. This allows performing equipment modernization in cities in conditions of developed residential building also with increase of plant capacity. Influence of climatic conditions on width of sanitary protection zones described. Shown that during the year boundaries of SPZ change at the same structure of equipment. The most correct is to specify interval in which boundaries of SPZ are located. These results allow selecting noise reduction measures more accurate.