• Affect final compost quality inspection process may require mechanically removing materials from (e.g., glass and plastic) containers or bags.

• Apart from these two, recovery of materials (e.g. plastic, glass or metal) and recovery of nutrients (e.g. nitrogen and phosphorus) from organic waste are methods that can be combined with the former mentioned methods landfilling and incineration.

• Materials such as plastic, glass and metal removed as they do not contribute to methane production.