Study on the Odor Production and Control of Swine Manure Composting

Two medium-scale composting experiments were carried out to study the effects of bulking agents, carbon-to-nitrogen ratio (C/N), aeration forms and additions on the swine manure composting under the moisture content of 68.8%. The changes of various indexes and the odor production and control were also studied. The results obtained were as follows: The odor produced with the ammonia volatilization during swine manure composting. This volatilization should be increased markedly as high pH value (pH＞7) and temperature (＞50℃). Reducing the composting materials pH value, adding suitable amendments and increasing the immobilization of NH⁺₄-N could reduce the odor. The addition of 1.5% calcium superphosphate to swine manure composting could reduce the pH value and the ammonia (NH₃) emission, and promote NH⁺₄-N to convert to other form of N. It could also increase the content of P. The finished composts made with the deodorant amendment could reduce the odor and had the best quality in the physical characteristics. It could be put into use in practice.