Abstract:
Objective To monitor the air pollution of a meat processing plant and its downwind area, for providing basic data for the setting of buffering zone.
Methods The concentrations of NH3, H2S and malodor were monitored by current national standard methods. A total of 9 sampling spots were assigned:6 were located in the buffer zone outside the plant, 50, 100, 200, 300, 400 and 500 m downwind from the pollution source; 2 in the plant area; and 1 at the pigsty as source of fugitive emission.
Results The factors influencing the concentration of NH3, PM10, H2S and malodor substantially were sampling season (P < 0.05), sampling time (P < 0.05) and distance away from the source (P < 0.05). The predominant factor for NH3 (R=0.627, P < 0.001), H2S (R=0.417, P < 0.001) and malodor (R=0.701, P < 0.001) was distance away from the source, and that for PM10 (R=0.466, P < 0.001) was air humidity. A remarkable correlation of exponential function was established either between the concentrations of malodor and NH3 (R=0.706, P < 0.001) or between the concentrations of malodor and H2S (R=0.366, P < 0.001).
Conclusion The concentration of NH3, H2S, PM10, and malodor are influenced significantly by sampling season, sampling time and distance away from the source, among which the distance is weighted as the most important one.