Technology of Utilization of Polypropylene Waste and Wastewater Sediments by Production of Building Blocks

Abstract

Plastic waste and wastewater sediment stored on sludge lagoons are generated in almost every city in Ukraine. Their disposal is an urgent issue nowadays. The paper shows the ways of polypropylene utilization as one of the most widely used thermoplastics in everyday life, as well as the problem of formation and storage of wastewater sediments. The proposed technological scheme of complex processing of the resulted waste by production of building blocks is based on the property of polypropylene as a thermoplastic to soften and melt at above 160 °C, while exhibiting adhesive properties to a number of materials. For the implementation of technological solutions for manufacturing of construction products, the adhesion properties of polypropylene to wastewater sediments were substantiated, heating modes of the raw material mixture of wastewater sediments and polypropylene waste were specified, and the ratio of raw materials in the mixture for thermal treatment was determined. The samples of building blocks with a mass content of wastewater sediment from 5 to 95% (dry weight sediments) were made in the laboratory. In these samples, the polypropylene content was reduced from 95 to 5%, respectively. It was experimentally determined that for the samples of construction materials with a mass content of wastewater sediment 40–50% (dry weight), a uniform distribution of raw materials that would ensure their high strength, was observed. The comparison of the qualitative characteristics of the samples of building blocks with the regulatory requirements for construction products revealed that the experimental samples met the current requirements and were not inferior to the counterparts from traditional raw materials. However, the construction materials made from waste are recommended for application in building of industrial warehouses and storage facilities, non-food storage chambers, garages or other structures that do not provide permanent storage of food or living place for humans or animals.