Although the collection and recycle of reclaimed plastics continues to increase, many types of plastics cannot be economically re-used. Also, existing technologies often are ineffective with mixed waste streams, which can lead to significant disposal issues. This project will determine the technical and economic feasibility of using recycled plastics as an alternative to perlite and polystyrene beads as a soil additive, used in the culture of plants. This would serve to demonstrate a new use/market for recycled plastics. Commodity reclaimed plastics such as polyethylene and polypropylene will be considered and evaluated as will other recyclates including mixed plastics rejected from emerging plastics separation/recycling technologies. In Phase I, samples of the recycled plastics from different sources will be blended with soil to create various nursery potting mixtures. Plants growth tests will be conducted, and the results will be compared with typical potting mixtures to determine the technical feasibility of using these recycled plastics as soil amendments. The costs of the recycled plastics from various sources will be estimated and compared to perilte and polystyrene beads to determine the economic feasibility of this concept.
Commercial Applications and Other Benefits as described by the awardee: The soil additive market has the capacity to use around 100 million pounds of recycled plastics per year worth approximately $10 million/year. Compared to a 50-50 perlite-polystyrene bead mixture, this would conserve 1.35 trillion Btu per year.
