Farm waste and effluents
Animal excrements are a natural source for fertilizing. Moreover, they represent a considerable potential of renewable energy for farming countries.
The anaerobic digestion takes naturally place in the context of sustainable development and a sustainable agriculture. It allows the production of a digestat more homogenous than its initial products and it is partly deodorised, enhancing its use in the agriculture.
In order to be more economically attractive, the digestion can include, beside the animal excrements ((liquid) manure), co-products whose energy potential is much higher and whose treatment offers an additional income. Numerous co-products varying from food processing wastes to dedicated crops can be used.
It must be noted however that the digestion process does not reduce the nitrogen content. In case the quantity of nitrogen is the limiting factor, specific technologies must be put in place to concentrate the nitrogen to an transportable fraction or to remove it.