Separation of plastics from municipal solid wastes

An integrated and sustainable resource management relies on the recycling of plastics from wastes, converting them into products with economical value. The efficient recovery of mono-component plastic products suitable for recycling, from municipal solid wastes (MSW), is limited mostly due to the difficulties in the separation of plastics from other types of plastics and from other materials such as paper and aluminium. In Portugal, like in many other countries, plastics are separated manually. However, automatic separation can be achieved using solid-solid separation processes developed in the field of mineral processing. Screening, magnetic and gravity separation processes are already used at large scale in MSW. The experimental work carried out, aimed to study the feasibility of separation of PET (polyethylene terephthlate) from PVC (polyvinyl chloride), two plastics that exhibit similar physical and surface chemical properties, by froth flotation. This work is part of a study that aims the establishment of a complete flow sheet for the automatic separation of the different components of MSW using only mass separation processes.