Air quality in the livestock waste compost pilot plant at the Colligate Livestock Station was assessed to quantify the emissions of aerial contaminants and evaluate the degree of correlation between them for different operation strategies; with the ventilation types and agitation of compost pile, in this study. The parameters analyzed to reflect the level of air quality in the agitation of compost pile, in this study. The parameters analyzed to reflect the level of air quality in the livestock waste compost pilot plant were the gaseous contaminants; ammonia, hydrogen sulfide, and order concentration, the particulate contaminants; inhalable dust and respirable dust, and the biological contaminants; total airborne bacteria and fungi.
The mean concentrations of ammonia, hydrogen sulfide, and odor concentration in the compost pilot plant without agitation were 2.45ppm, 19.96ppb. and 15.8 when it was naturally ventilated, and 7.61 ppm, 31.36ppb, and 30.2 when mechanically ventilated. Those with agitation were 5.50ppm 14.69ppb, and 46.4 when naturally ventilated, and 30.12ppm, 39.91ppb, and 205.5 when mechanically ventilated. The mean concentrations of inhalable and respirable dust in the compost pilot plant without agitation were 368.6㎍/㎥ and 96.0㎍/㎥ with natural ventilation, and 283.9㎍/㎥ and 119.5㎍/㎥ with mechanical ventilation. They were also observed with agitation to 208.7㎍/㎥ and 139.8㎍/㎥ with natural ventilation, and 209.2㎍/㎥ and 131.7㎍/㎥ with mechanical ventilation. Averaged concentrations of total airborne bacteria and fungi in the compost pilot plant without agitation were observed to 28,673cfu/㎥ and 22,507cfu/㎥ with natural ventilation, and 7,462cfu/㎥ and 3,228cfu/㎥ with mechanical ventilation. They were also observed with agitation to 19,592cfu/㎥ and 26,376cfu/㎥ with the natural ventilation, and 18,645cfu/㎥ and 24,581cfu/㎥ with the mechanical ventilation.
It showed that the emission rates of gaseous pollutants, such as ammonia, hydrogen sulfide, and oder concentration, in the compost pilot plant operated with the mechanical ventilation and with the agitation of compost pile were higher than those with the natural ventilation and without the agitation. While the concentrations of inhalable dust and total airborne bacteria in the compost pilot plant with the natural ventilation and with the agitation, the concentrations of respirable dust and total airborne fungi in the compost pilot plant with the mechanical ventilation and agitation were higher than those with the natural ventilation and without the agitation of compost pile. It was statistically proved that indoor temperature and relative humidity affected the release of particulates and biological pollutants, and ammonia and hydrogen sulfide were believed primary malodorous compounds emitted from the compost pilot plant.
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