Biodegradability is the ability of substances and organic materials to decompose into simpler substances due to the enzymatic activity of microorganisms. When the biological process is completed, the total transformation of the initial organic substances into simple inorganic molecules such as water, carbon dioxide and methane is obtained.
The phenomenon of biodegradation is part of the natural cycle of life on earth, based on carbon. Thanks to the activity of photosynthesis of plants and algae, and the inexhaustible solar energy, the carbon dioxide in the atmosphere is absorbed to synthesize the sugars and other substances used by vegetables to grow and develop. Through the food chain, the flow of matter and energy passes from the plants to the herbivores and from these to the carnivores. When plant and animal organisms die, microorganisms "always present in the environment" are nourished by organic material through biodegradation processes that release water and carbon dioxide into the atmosphere, thus closing the cycle.
By imitating and valuing these natural processes, organic waste from human activities can also be eliminated through transformed by biodegradation.
For this operation to be effective it is necessary to identify the ideal environment in which this phenomenon can be maximized and it is necessary to define a process duration that is "industrializable" and compatible with the production rhythms of this organic waste.
In nature, each organic waste has its degradation times, hay and wood use need more time than starch and cellulose. In the same way, in cold and dry environments the biodegradation processes are slower than in hot and humid environments.
This means that biodegradation depends very much on the chemical nature of the substance or matter to be biodegraded and on the environment of biodegradation. The environments in which biodegradation occurs at a good pace and that allow allowing industrial management are those of composting and anaerobic digestion.
In these systems, therefore, organic solid waste can be treated, including processed organic waste (for example biodegradable plastic) that has a rate of biodegradation compatible with these treatments. In the case of composting, a mature compost (fertilizer) will be obtained and in the case of anaerobic digestion (followed by stabilization in composting), biogas (and therefore energy) and compost will be obtained.
Another biologically active environment is the soil: some materials can be completely biodegraded in the soil and this property can be used in specific applications such as mulching (covering the soil).
Compostability is the capacity of an organic material to be transformed into compost through the composting process. This process takes advantage of the biodegradability of the initial organic materials to transform them into a final product that takes the name of compost. The compost is therefore the result of the disintegration and aerobic biodegradation (ie in the presence of oxygen) of organic (usually waste) material: the mature compost is similar to a fertile substrate and because of its richness in organic substances it is used as fertilizer.
Composting can be practiced at the home level on a very small scale or at an industrial level. The latter is fed with organic waste from households and waste from agricultural production and other sectors and is carried out in specific plants that ensure the correct management of the process.
What happens in the composting plant is not very different from what can sometimes be seen in the field: piles of organic material (waste, excrement, sawdust, wood chips, etc.) produce heat and exhale steam, as if they were burning but without fire. In fact in those heaps is being carried out biodegradation by microorganisms that consume the nutrients and transform the initial residue into a set of organic substances called precisely compost.
In industrial plants this product is sterilized and stabilized so that it lacks pathogenic microbes and putrescible material. Also, before its commercialization, its quality is controlled, since it must meet a series of requirements established by law.
RECYCLABLE AND REUSABLE
They are the conventional products made with recyclable polyethylene, nylon and PET, which take up to hundreds of years to disappear if they are not treated in the convenient recycling plants to be used again in other products. Therefore, these types of disused items must be deposited discarded in the garbage containers selected for this purpose, usually in yellow.
Recyclable Biodegradable Compostable