Objective To quantify the unorganized emission of nonmetallic mineral production and to propose the health protection zone standard for it.
Methods The detected enterprises which represented the national advanced technology level of nonmetallic mineral production were selected through industry data. The analogic enterprises of similar production process and location with same raw materials were selected. The quantity concentration of fugitive emission (Qc) was detected by field monitoring. The health protection zone for cement and lime industry was calculated by ground concentration inverse method, that for asbestos industry by flux method, and that for graphite industry by material balance method, to analyze the health protection zone for similar enterprises of different scales. Residential health epidemiology survey and rank sum test were adopted to give reasonable health protection zone standard.
Results The health protection zone standard for nonmetallic mineral production in line with the average wind speed of recent 5 years were as follows:300 m, 200 m and 200 m for cement industry; 400 m, 300 m and 300 m for lime industry with production scale ≤ 20& #215;104 t/a, and 500 m, 400 m and 300 m for that with production scale > 20& #215;104 t/a; 400 m, 300 m and 200 m for asbestos industry; 800 m, 700 m and 600 m for graphite industry with ultra high power graphite electrode < 3& #215;104 t/a, and 1 200 m, 1 200 m and 900 m for that with ultra high power graphite electrode ≥ 3& #215;104 t/a. A total of 347 questionnaires were available and showed significant differences of symptoms distributed in different health protection zones (P <0.05).
Conclusion Wind speed and production scale are the factors considered in setting health protection zone standard. It is feasible to make the standard according to industry classification.
DownLoad: