Improving Compost Quality by Controlling Nitrogen Loss During Composting

Ammonia emission represents the major route of nitrogen loss from composting mass; thus most efforts are directed toward controlling the ammonia emission. Factors affecting ammonia emission, such as substrate properties, aeration/mixing, temperature, pH, and microbes, are interrelated, and modifying one parameter will affect the others. Often the method applied to reduce the NH3 loss reduces the organic degradation, thus increasing the composting period. Considering the composting optimum conditions, there is not much room to reduce the nitrogen loss through process modifications. Thus, adsorption and precipitation of ammonia using zeolite and struvite formation, respectively, appear promising. However, the methods should be modified to balance the organic degradation and the nitrogen conservation. Ammonia emission is unavoidable in a good composting process, but can be reduced through innovative approaches. This chapter reveals the factors affecting ammonia emission and the strategies to control the nitrogen loss during composting.