AIR POLLUTION FROM SWINE PRODUCTION FACILITIES DIFFERING IN WASTE MANAGEMENT PRACTICE

Gaseous emissions from swine manure storage systems represent a concern to air quality due to the potential impacts of hydrogen sulfide, ammonia, methane, and volatile organic compounds on environmental quality, human health, and wellbeing. The lack of knowledge concerning functional aspects of swine manure management systems has been a major obstacle in the development and optimization of emission abatement technologies for these point sources. In this study, a classification system based on emission characteristics and solution-phase concentrations of phosphorus (P) and sulfur (S) was devised and tested on 29 swine manure management systems in Iowa, Oklahoma, and North Carolina in an effort to elucidate functional characteristics of swine manure management systems. Four swine manure management system classes were identified that differed in solution-phase concentrations of P and S, methane emission rate, odor intensity, and air concentration of volatile organic compounds (VOCs). Odor intensity and the air concentration of VOCs emitted from swine manure management systems were shown to be strongly correlated (r2 = 0.88). The concentration of VOC in air samples from the 29 swine manure management systems was highest with high-load, outdoor manure management systems (Type 2). These swine manure management systems were also observed to have the highest odor intensity levels. Volatile organic compound (VOC) emission rate and odor intensity for swine manure management systems were found to be inversely correlated with methane and ammonia emission rates. Emission rate of methane, ammonia, and volatile organic compounds were found to be dependent upon manure loading rate and indirectly influenced by animal numbers. Data show that current swine production activities have the potential to produce up to 386 tons of air pollutants • site−1 • year−1.