Do meteorological parameters have an impact on dust nuisance problem in the vicinity of Lakvijaya coal fired power plant in Sri Lanka?

Abstract

Storing coal and piling up the resultant ash in open yards is a common practice in many thermal power plant operations in developing countries which may lead to dust nuisance problem in the vicinity of the power plants. However, meteorological parameters may have an influence on the dispersion and deposition of dust particles from pollution sources. The present study assessed the changes in dustfall rate with meteorological parameters (rainfall, atmospheric temperature and wind speed and direction) in an area between 500 m and 3 km from Lakvijaya coal fired power plant (LCPP) in Kalpitiya Divisional Secretariat Division from June to November 2019. Sampling sites included eight (08) locations covering all the directions of LCPP in the study area. Dust falls were collected and analysed according to ASTM D1739 methods. The meteorological parameters were collected from the Department of Meteorology. Monthly mean dustfall rate of the study area was statistically analysed with each meteorological parameters concerned over the study period. According to the results, dustfall rates varied significantly during the study, with the highest recorded in July (437.00 ± 208.00 mg m-2 day-1) and the lowest in November (54.10 ± 15.00 mg m-2 day-1). Rainfall exhibited an inverse trend to dustfall, increasing substantially from 26.2 mm in June to 638.4 mm in October. Temperature decreased gradually from 30.1°C in June to a minimum of 27.3°C in October. However, the statistical analysis revealed that, dustfall rate had a moderate positive correlation with atmospheric temperature (r = 0.312, p = 0.031) and a moderate negative correlation with rainfall (r = -0.312, p = 0.031) and the correlation with wind direction and wind speed were not statistically significant. Therefore, according to the study, within the study period, changes in atmospheric temperature and rainfall had an impact on variations in dustfall rates in the study area. Also, the LCPP could be a significant source of dust in the study area as the dust collected near the coal yard was dominated by coal dust. It is recommended to carry out further research to find out in which way rain reduces and atmospheric temperature promotes dustfall rate in the study area.