Composting organic material is as natural a process as can be. It is simply the biological way of breaking down complex organic matter into simpler inorganic forms that can be utilised by other forms of life. Nature has its own agents working this process: Ants, termites, worms, bacteria, fungi, yeasts etc…. While, there are two types of composting: Aerobic (with air) and Anaerobic (in the absence of air), the project at hand will only consider the former.
As human societies began to consume more- and waste more – there started a realization that there may be a way to speed up the natural process so as to keep up with the larger amounts.
As such there are now large scale composting plants worldwide while there are many farms, institutions or even individual homeowners or gardeners who are involved in composting.
For a scale that is not too large, figure (2) shows, the setup shown has three enclosures: one for the new feed (left), another for the partially processed material and a third for the material nearing completion. Such a system could be duplicated and made into several 3-enclosure units as needed.
Another system is the “tumbler” system (Figure 3) which allows simple turning of the compost unlike the simple wooden enclosures which require manual turning. Tumblers allow faster completion of the composting process if operated correctly. For larger volumes, several tumblers would be used simultaneously.
For large scale processing, it is common to simply have the compost piled in ling windrows. These are usually very long and not very wide so as to allow a tractor (or similar) to turn them over. In addition, there are several parallel rows which progress from fresh material to material that is fully cured.