High density polyethylene is the most widely used plastic in the world, due to its excellent properties.
It is lightweight, mechanically and chemically resistant, does not corrode, has a low cost and above all has the versatility of being manufactured according to the consumer's needs. All these characteristics mean that HDPE has a long life, a useful quality when it is used, but a problem when it is discarded. That is why it is necessary to have treatment techniques for this plastic. The most recommended is the 3R's; Reduce, Reuse and Recycle.
The problem lies in creating ecological awareness of the environmental impact of the uncontrolled and irresponsible use of HDPE by the consumer. While for the industry it is a challenge to make its process more efficient and not generate unnecessary waste.
Coding
The classification system was developed by: The Society of the Plastics Industry (SPI) and has been adopted worldwide.
It is based on a simple symbology that allows in the collection and recycling process, to identify and separate the different products.
It is composed of three arrows forming a triangle with a number in the center and letters at the base. The symbol is molded by means of an insert or engraving, either on the bottom of the container, or close to it, depending on the geometry of the item.
The minimum recommended size is 2.5 cm. For quick recognition. Small base containers may bear the symbol in a proportional size; however, other regulated dimensions are 1.2 cm and 1.6 cm.
If a container is manufactured in a new model and with resins different from those traditionally used, it is the responsibility of the transformer or mold manufacturer to change the code by means of an insert, in order to identify the raw material used.
Solutions to minimize plastic waste
There is a system that indicates the way to treat waste, it shows the activities to follow taking into account that one should not be considered without having exhausted the previous one. The steps are as follows:
- Reduce
- Reuse
- Recycle
- Recover
- Waste
Reduction starts at the source. It consists of using the smallest possible amount of materials to be discarded. For this reason, more resistant plastics, additives and processes have been developed to manufacture lighter and thinner products. In this point, the factories dedicated to plastic transformation and, to a lesser extent, the consumer, have the greatest incidence in the generation of waste.
The reuse of plastics consists of maximizing the useful life of products through a system of returnability, without the need to destroy or recycle them.
An example is plastic bags, which can be used more than once for different activities, thus giving the product a longer useful life.
The greatest amount of waste is generated in the home (approximately 60%), which is why ecological awareness should be created in all households to reduce plastic waste.
Recycling should be the third option and is performed once the products can no longer be used for their original purpose. It consists of collecting and separating the plastic from the rest of the solid waste, to be processed and transformed into a new product.
Recycled plastics are used in a large number of non-food applications due to sanitary requirements to ensure that no contaminants can migrate to the surface of the product.
The concept of reclaiming is the use of chemical methods to obtain raw materials or energy from plastic waste.
The last stage in waste treatment is waste, which is defined as any object that no longer has any use or value, and should only be considered when products have reached their maximum use and recycling is not justified.