The Recycling of Construction Foams: An Overview

Abstract

AbstractIn 1987, the United Nations Brundtland Commission defined sustainability as “meeting the needs of the present without compromising the ability of future generations to meet their own needs.” Yet, after all these years, the humankind is dealing with catastrophic environmental problems which may jeopardize the future generations wellbeing. One cause of such issue is pollution associated to polymer’s disposal. Polymers are mainly produced using petroleum derivatives and/or non-degradable. In addition, after their use, they are normally disposed in land fields or burned for energy. Yet, due to environmental problems, these solutions are not valid options, so plastic wastes must be recycled and used to produce new materials. This circular economy concept is not only a requirement for preventing pollution but is also a need for the reduction of the costs associated with their production and for the enhancement of the eco-efficiency of materials. Furthermore, this approach also addresses the risk of shortage of raw materials in the medium future. With this in mind, this document intends to give an overview of the recycling of construction foams with special focus on polyurethane (PU) and polystyrene (PS) foams. It aims to highlight the possible routes to recycle construction foams, presenting the differences and challenges of recycling different types of polymers. In that perspective, chemical and mechanical recycling routes are discussed, as well as energy recover alternatives. Finally, life cycle analysis (LCA) reports of these products are presented.