Repsol YPF

Environmental education in favour of a sustainable and equitable society implies constant learning, based on a respect for all life forms. Working individually but thinking globally, many people have taken this doctrine on board. As a result of their commitment to protect natural resources and the environment, they separate their domestic waste every day. However, the majority of people do not know what happens to it afterwards. What is the process? 

Initially, rubbish is classified, as well as by its origin (industrial, domestic, etc.) it is classified according to its composition: organic waste, in the case of biological refuse; inorganic waste if it is industrial rather than natural in origin; and dangerous waste, all refuse which represents a potential danger and as such must be treated in a particular way. This last category includes infectious medical material, radioactive waste, etc.

Free raw material

Recycled refuse is used to make various materials. For example, polyethylene terephthalate containers, better known by the acronym PET, in other words, plastic bottles, can be converted into bricks. After being classified by colour, they are pressed and compressed before being taken to a mill. This element is mixed with cement, sand and a chemical product which assists the combination process, and when it sets it is suitable for use as joists or blocks for building walls, roofs or pavements.

The cellulose obtained from some organic waste can be turned into light oils, if it undergoes a hydrogenation process involving high temperatures and pressures of 300 atmospheres. 

Compost is another product which is obtained from organic waste, specifically once it has fermented. It is transformed through controlled microbial action, but it requires exhaustive pre-selection in order to remove all inorganic material. Compost can be used as an excellent fertiliser in parks and gardens.

This way, technology makes use of free raw materials and manufactures low-cost products as well as using part of the rubbish contaminating the environment and reducing the consumption of virgin raw materials. It must not be forgotten that only seven countries, representing only 20% of the world population, consume over 50% of the planet’s natural and energy resources. Over-exploiting these resources and increasing pollution is threatening the regeneration capacity of the ecosystems.

However, not all waste is currently recycled, in other words, it is not all transformed into a material that can be reused. Neither is it all recovered. This is unusable waste, which is a problem for many societies. A large percentage of waste is incinerated. However, by mixing the ashes produced by incinerating toxic substances a useful material can also be obtained, for example, for paving the streets.

There is another technique, pyrolysis or dry distillation, which transforms organic material into products with a high energy content. This technique can be used to obtain acetic acid, light oils, tar and methanol, products which are useful as fuels and raw chemical products. 

Cyclical process

Reintroducing waste into the production cycle is one of the most effective ways of really reducing waste. This requires product manufacturing to be oriented towards reuse and recycling, both with regard to packaging and the materials used to produce them. 

The solution involves converting waste management into a profitable industry; this involves the correct separation and reduction of waste, protecting the water table, fauna and flora, as well as generating employment.

That way, instead of a production system that consumes and disposes of waste, the future is moving towards a cyclical production process, where most of the waste from production and consumption is introduced into the production cycle just as in nature.

Related articles:

- Pneumatic refuse collection