DISPERSION MODELLING OF AIR EMISSION FROM A RICE MILLING PLANT
The study investigated the air quality impacts of Rice Mill using the ISC-AERMOD View. Contributions of steam boiler and electric power generators in the mill to ground level concentrations of criteria air emissions were established.The maximum ground level concentrations of air pollutants presently emitted by the steam boiler are 1-hour averaging period concentrations of 1.4 – 177.3 µg/m3 with 24-hour level of 0.3 – 43.5 µg/m3. Simultaneous operations of the steam boiler and electric power generators give 1-hour averaging period concentrations of 29.7 – 257.8 µg/m3 with 24-hour levels of 8.8 – 95.8 µg/m3 . The simultaneous operations of the steam boiler and the electric power generators add about 0.41 – 84.78% of the respective investigated air pollutants limits to the ambient air quality of the host environment. Occasionally the daily NOX limits from this scenario 2 could breach the ambient limit whenever all the three electric power generators are simultaneously operated with the steam boiler.