Abstract:
Objective To evaluate the influence of coking plants on the air quality of living and manufacturing environment of a surrounding coal mine area.
Methods Ambient air samples of nitrogen dioxide (NO2),hydrogen sulfide (H2S),ammonia (NH3),benzene (C6H6),toluene (C7H8),dimethyl benzene (C8H10),hydrogen cyanide (HCN),and carbon monoxide (CO) were collected from selected spots in the coal mine area.According to the Ambient air quality standard (GB 3095-1996), Comprehensive emission standard of air pollutants (GB 16297-1996),and Emission standard of pollutants for coking chemical industry (GB 16171-2012),the samples were analyzed to understand the air quality in the vicinity area.
Results The analysis showed that all of the NH3 samples,75.52% of the H2S samples,and 10.94% of the NO2 samples exceeded the national standard limits.The results of C6H6,C7H8,C8H10,HCN,CO,and NO2 were qualified.In the eastern coal mine area closest to Plant C,the levels of NO2 were higher than those in the northern part,and the levels of CO were higher than those in the southern,western,and northern parts (P < 0.05).In the sampling time session 2:00-6:00 and 14:00-18:00,lower unqualified proportions of H2S and NO2 samples were recorded,and the levels of NH3 and H2S were significantly lower than those in 8:00-12:00 and 20:00-24:00(P < 0.05).The levels of NO2 were significantly lower in 14:00-18:00 than in 20:00-24:00(P < 0.05).
Conclusion Pollutants from coking plants surrounding the coal mine area have certain impacts on the quality of air in the coal mine area,and show a trend rising in the morning,then falling in the afternoon,rising in the evening to the highest,then falling again in the next dawn.Given this,appropriate precautions should be taken to protect the health of workersgroup