Composting is a biochemical process through which material is mainly used as fertilizer for gardens but above all for the so-called biological cultivation.
The final product, called compost, is obtained starting from organic material of vegetable or animal type which is attacked and decomposed by microorganisms, generally aerobes, which transform it. Only later can other organisms, such as earthworms, snails and insects, contribute to the formation of the final compound.
This process can be performed both domestically and industrially and is a great way to recycle material that would otherwise be lost and disposed of in an alternative way.
The raw material that is generally used to make compost comes from domestic waste, such as organic waste derived from pruning, kitchen waste, gardening waste, various types of sewage, manure.
These elements are then organized so as to make the process carried out by the microorganisms that can be bacteria or even fungi easy.
Generally it is an aerobic process, that is that it requires the presence of oxygen and therefore of air, which can occur at different times depending on the quantity of the material to be decomposed and according to the type of substances contained therein.
As already mentioned previously, the compost obtained by this process is useful as a fertilizer for the soil and is often used before plowing. Thanks to the abundance of nutrients and the great microbial flora from which it is composed, it makes the soil more fertile giving it even a better structure.
This is therefore a process that makes it possible to limit the production of toxic substances given by the mass disposal of wet or naturally derived waste that are made useful in secondary processes. Some define composting as the closure of the food chain because the organic substances of which every living being is formed return to nature and are exploited by itself.
However, what are the requirements so that the waste listed above can become compost?
First of all we must not forget that it is the micro-organisms of the soil which are bacteria and fungi that all carry out the decomposition process, it is therefore necessary that the ideal conditions are recreated to which they perform their function. There are mainly three characteristics that the environment must possess:
° Nutrients data but carbonaceous and nitrogenous materials;
° Air that enters through specific cracks;
° Constant humidity given not only by the wet material that is inserted in the compost bin, but also by any rain that may occur during the composting process.
As already mentioned, not all materials can be used for the production of compost, in fact it can only be introduced:
- Paper and cardboard;
- Residues of clothes made from 100% natural material (eg cotton);
- Bedding of herbivorous animals;
- Material derived from pruning (preferably shredded in this way will be more easily attacked);
- Coffee grounds, nut shells, egg shells, tea filters.
- Various types of nitrogen waste, including wet waste from household waste.
How is composting done?
Composting can be carried out on a domestic scale and on an industrial scale. In the first case it is, first of all, necessary to have a garden available in which to obtain a strip of land to be dedicated to the accumulation of the substances to be composted. Everything can be done either in special containers that are easily found on the market or the so-called composter can be recreated independently with materials to be recycled, for example in wood.
In reality these are the ideal conditions to make the process quick and effective, but can also be done inside holes dug in the ground. In the latter case, two must be available, one will be active while the other will be at rest and work cyclically and alternately.
The dimensions of the holes must be related to the quantity of waste to be processed.
The material should preferably be positioned in a sunny and more isolated area. As the process carried out by microorganisms is aerobic, to ensure proper ventilation it is advisable to periodically turn the heap so as to perfect the infiltration of air inside it.
It must be considered that the period of time necessary to obtain a compost of good quality varies from 3 to 4 months (fresh compost), but it must be taken into account that in winter the times expand due to the lowering of temperatures, while, for the opposite reason in summer is reduced. To obtain the so-called mature compost requires a period of time of about eight months.
As regards industrial composting, it exploits the same principles as domestic composting, but it can also use sludge derived from water purification. Industrial composting offers two advantages, the first is optimal process control, the second is the possibility of eliminating any harmful and uncomfortable parts such as pathogens for agriculture or any elements that would make the raw material unusable.
At the industrial level, this process requires ample space for accumulation.
Why perform composting?
This is one of the recycling processes that each individual with the means mentioned above can perform even on a small scale. In recent times it has been strongly encouraged because it avoids a greater mass of urban solid waste to be disposed of and like any recycling process is healthy for the environment and therefore for humans.