The production of compost is both a mechanical and a biological process. The raw materials must first be separated, collected, and shredded by mechanical means before the biological decomposition process can begin. In some cases, the decomposition process itself is aided by mechanical agitation or aeration of the materials. After decomposition, the finished compost is mechanically screened and bagged for distribution.
By separating home yard wastes and turning them into compost, it is estimated that municipalities can reduce the amount of trash going to landfills by about 20%. While that is a significant reduction, it is expected that even more trash will have to be diverted from landfills in the future. Materials such as soiled food packaging, disposable diaper padding, food scraps, natural fiber rags, pieces of wood, and other organic materials could all be composted. To do this, municipalities may have to establish municipal solid waste (MSW) treatment facilities to separate the compostible materials from the harmful materials, such as discarded batteries, motor oil, asbestos, and many household chemicals.