Incorporação de resíduos de processamento de lentes oftálmicas na produção de concreto

Abstract

The expansion of the consumption of ophthalmic lenses in Brazil in recent decades has also triggered potential environmental impacts due to the disposal of waste from their processing, which consists of shavings from the surfacing and cutting of ophthalmic lenses, and lenses not approved in quality control. Its materials are, more often, composed of polymeric origin which, being a material that decomposes slowly when discarded, causes its presence in large quantities both in landfills and in nature. The expansion of the civil construction industry resulted in the growth of environmental damages inherent to its activities, direct and indirect, especially those caused by the demand for sand extraction, mainly used in the production of concrete, related to damages such as emissions into the atmosphere, water and land, as well as the consumption of non-renewable resources. Therefore, this study aimed to analyze the possibility of incorporating polymeric waste from lens processing in the production of concrete, in partial replacement of fine aggregate. Two types of waste were collected in an optical laboratory located in Recife/PE, polycarbonate and resin. The materials were submitted to infrared spectroscopy (FTIR) where a possible presence of alcohols/phenols and carboxylic acid was observed in the polycarbonate and resin residues, respectively. The moisture content and unit mass of both were also determined to calculate the concrete mix. Through a dosage study, a standard mix was determined, deriving from it the other mixes, constituted by the volumetric replacement of sand in the contents of 2, 6 and 10% for each type of waste. Workability, compressive strength, bending tensile strength, water absorption, void index and specific mass were analyzed. Altogether, 178 samples were experimented. A reduction in the consistency of the concrete in the mixes with residue incorporation was observed, being necessary the addition of water to reach the established abatement. The results obtained would enable the use of this concrete in concrete pavements, permeable pavements, industrial floors, cell galleries and structures in environments of class III of environmental aggressiveness.