NH3 dynamics in composting : assessment of the integration of composting in manure management chains

The Dutch animal production sector copes with a manure problem. Their high nitrogen content makes manures popular fertilizers, but most of this nitrogen is emitted before it could be used by plants. Ammonia is the main emission form during the manure management chain of storage, transportation and land application. Composting these manures could improve their general storage and transport features, and produce stable composts. Still, the nitrogen retaining efficiency of composting is a matter of debate. This aspect of high- and low-tech composting treatments was examined through a technological research. The low-tech applications appeared to retain the nitrogen from ammonia by facilitating a complete nitrogen conversion process. High-tech processes do lose most of the ammonia, but this ammonia can be trapped to manufacture a separate fertilizer product. Although composting treatments are not free of emissions, their abilities to control the form and extent of harmful nitrogen emissions makes them potential choices in manure management.