Decomposition, or the breakdown of raw organic materials into finished compost, is a slow and complicated process that requires both chemical and biological processes.
The process of composting is known as “composting,” and the finished result is known as “compost.”
Compost is produced in one of two ways:
- ANAEROBIC (without oxygen) decomposition.
- AEROBIC (with oxygen) decomposition and stabilization.
Anaerobic Decomposition (Fermentation)
Anaerobic decomposition occurs naturally, such as in the decomposition of organic muds at the bottom of marshes and in buried organic materials that lack oxygen. Putrefaction produces unpleasant aromas of hydrogen sulphide and reduced sulfur-containing organic molecules, such as mercaptans, when organic matter is intensively reduced (any sulfur-containing organic compound).
Anaerobic putrefactive degradation of organic material occurs. Living creatures that do not require air in the traditional sense break down organic molecules. To live and build cell protoplasm, these organisms consume nitrogen, phosphorus, and other nutrients, but they convert organic nitrogen to organic acids and ammonia. The carbon from organic substances that is not used in cell protein is mostly released as methane in its reduced form (CH4). Carbon dioxide can be produced from a little amount of carbon (C02).
Because anaerobic decomposition of organic matter is a reduction process, the final product, humus, is prone to some aerobic oxidation when applied to soil, which means it may appear to disintegrate even more after exposure to air. This oxidation is mild, occurs quickly, and has little bearing on the material’s use on the soil. In other words, anaerobic decomposition produces far less heat than aerobic decomposition.
If contaminated materials are utilized for composting, the lack of heat generated in the anaerobic breakdown of organic matter is a significant disadvantage. Pathogens and parasites require high temperatures to be destroyed. As a result of the adverse environment and biological antagonisms, harmful organisms finally vanish from the organic material during anaerobic decomposition. The elimination is slow, and the material must be kept for six months to a year to ensure that diseases such as Ascaris eggs, nematodes that are among the most resistant of the fecal-borne disease parasites in wastes, are relatively completely destroyed. As a result, build compost this year and use it the following year.
Organic matter, on the other hand, can be decomposed anaerobically to form compost. For example, grass clippings or other high nitrogen materials, shredded leaves, kitchen wastes, a small amount of stable manure, or other biodegradable materials can all be decomposed in a hefty plastic bag. However, because anaerobic compost has a strong odor (and may need to be ventilated before use), it isn’t always the first choice for homeowners. See Structures for more information.