Composting is a biological process in which organic matter is aerobically (in the presence of oxygen), converted into humus-like compounds by micro-organisms. During this process heat, water, CO2 and odour compounds are released. Due to the evaporation of water and the decomposition of organic matter, the dry matter content increases and the volume decreases (Melse, et al. 2004). Composting installations for the composting of manure are offered by various parties. Manure is firstly separated into a thin and a thick fraction. The solid fraction is composted in a drum. The thin fraction is stored. Composting is an aerobe process, the material is therefore aerated, either with air bubbles or by mechanically turning the material. If there is insufficient structure or carbon present in the material, additional material such as straw can be added to get the process started. During the composting process heat is released, if the process is properly controlled, temperatures can reach over 70 ° C and the process can be valorised.