Plastic waste materials represent approximately 50% of what remains after sorting the compostable waste. Plastic bags in particular play a very major role in pollution. Solutions for transforming these into construction materials are offered.
Gevalor is interested in recuperating plastic waste materials that represent approximately 50% of what remains after sorting compostable waste.
In terms of plastic waste, the importance of bags, which have a large surface area to weight ratio, is obvious. Because they play a major role in pollution, contributing to the clogging of sewers, the covering of fields and soils and the blocking of the digestive systems of land or marine animals.
Under certain circumstances, it is possible to recycle bags as a resin that is capable of being substituted to virgin resins for regenerating consumer products. In many other cases, the contaminants with which they are loaded do not allow this type of recycling without washing, which can prove prohibitive for both economic and environmental reasons.
In collaboration with the “Centre Technique de Garoua” (Cameroun), an approach is being jointly defined to manufacture self-locking paving stones by melting plastic bags and mixing them with sand.
Strict operating conditions (elimination of bags that contain halogen products, defining the proportions of sand and plastics, granulometry of the sand and reaction time) have been defined. These enable the avoidance of noxious smoke emissions during the heat-treatment process and the producing of paving stones of reproducible quality and of very good mechanical strength.
An analysis of the technical characteristics and, of the production costs of these paving stones has proved to be positive compared with basic concrete products that are currently on the market in Madagascar.
Tests for also producing fire-resistant tiles and bricks as well as paving stones are also underway.