Composting
Composting is a process by which organic substances such as green waste or non-animal food waste is decomposed or rotted until it has become a stable, humus substance that can be used as a plant fertiliser. The process is normally carried out within as short a period of time as possible and in a manner that avoids odour emmissions as much as possible. Composting sites can range from farm yard operations right up to industrial sized operations involving large composting plants.
The composting process can be carried out outdoors in an open environment using a windrow system or in a closed structured environment involving enclosed rotting tunnels followed by maturation in an open pile.
Raw materials for composting can include green waste, fruit and vegetable waste and sewadge sludge. The mature of the raw material will determine the most appropriate composting system.
The composting process will generally involve the following machines
- Shredder - high speed or low speed used mainly on green waste
- Mixer - used when material is varied in composition or when sewadge sludge is being added
- Compost turner - used to turn composting windrows or maturing composting piles
- Screeners - drum screens or starscreens to separate fine and coarse fractions in finished compost product
