ภาวะมลพิษทางอากาศจากอุตสาหกรรมบ่มใบยา ของจังหวัดเชียงใหม่ / สราวุธ สมประเสริฐ = Air pollution from tobacco curing industry in Chiangmai Province / Sarawut somprasert
The main purpose of this study was to investigate the air pollution from tobacco curing industry in Chiangmai province. The study was planned to find out the concentration of the pollution and its emission under the condition of mountainous area and cool climate of Chiangmai by using a mathematical model analysis. Phrao District was chosen to be the example area of Chiangmai, due to its largest number of tobacco curing barns and its valley plain. Relavant data on meteorology and pollution sources were gathered and then analyzed with the mathematical model ISCST. The model runs were also worked out to suggest the improvement of the situation in three different ways: increasing stack heights, reducing emission rates with different fuels at their peak heat efficiency, and curing a suitable amount of tobacco at each barn, according to its location. The major results were concluded as follows: The weather condition during the study period winter of 1993-1994 was 0.95 m/s wind velocity, most from the south direction, and the calm condition occurred 22 % from 10:00 PM to 06:00 AM; The ISCST model showed that the highest hourly average concentration was 3039 µg/cu.m at Ban San Pongat 10:00 PM in November when the tobacco curing was at the maximum. Twenty-four hour average concentration was 771 µg/cum. at the same grid point. The reason was that the calm condition occurred 30 % more often in December than in November causing the pollutant to be subjected to more stable atmospheric condition; The SO2 concentration at the hillside were 7 % higher than those at the flat area; For the improvement solutions the increase of stack height from 6 to 10 meters could reduce 15 % and the semi-bulk typed barns could reduce 40 % of the SO2 concentrations.
