Table 5.7.1 shows main materials usable in composting. Husk and woody materials have a

low biodegradable material index so their decomposition takes time but are effective for improving soil and can be used in combination with other materials to produce high quality compost. Raw garbage contains many materials impossible to ferment such as plastic, metal, and glass and also requires thorough sorting and the right preprocessing. Sludge may require special measures for dealing with heavy metals, etc.

Among the recycling technologies of composting, biogas, drying, carbonization, livestock feed, and incineration, composting can use vaious kinds of materials and offers significant advantages in terms of technology and distribution. However, amount and period of the product demand are limited, and some regions have excess compost stocks. Future production efforts will require elaborate quality control, composting of all material produced in a region, and regional consumption of the entire amount produced in those areas.

Further information

Japan Livestock Industry Association Ed., Composting Facility Design Manual(2003) (in Japanese) Japan Organics Recycling Association Ed., CompostingManual2004 (in Japanese)

Livestock Industry’s Environmental Improvement Organization Ed., Livestock Dung Process Facility — Machine Setup Guidebook (compost processing facility version) (2005) (in Japanese)