Recuperação de resíduo na indústria metal mecânica: de passivo ambiental a matéria prima para construção civil

Abstract

To ensure consumer market expectations and exponential growth, companies need to act with quality improvements in the environment. It is inferred that it is necessary to develop alternatives to minimize environmental impacts and associate these improvements with the reduction of production costs. Given this scenario, the objective of this work is to evaluate the reuse of waste generated in the metalworking industry from the polishing processes that generated environmental liabilities. It was defined that the reuse will not be fine aggregate for the manufacture of concrete blocks, for this different proportions of replacement of sand by polishing sludge were made - 5%, 10%, 15%, 20% - and evaluating the physical performance Mechanical analysis of the concrete blocks produced, it was necessary to classify the waste following NBR 10004/2004 and after the result that the waste is classified as non-inert, that is, non-hazardous waste became viable with the evaluation. subsequently, the relationship between the mechanical strength and water absorption of the blocks was evaluated following NBR 6136/2016. In the sample dosing step, define the amount of material for each reference mix, a factor that influences the ratio of sand to polishing sludge. It was noted that the different proportions of incorporation of the polishing sludge in substitution of the fine aggregate sand met the filling of water absorption (≤10%). The resistance to resistance of the concrete blocks was greater than 3,0MPa in all traits, that is, it met the value indicated for class C blocks. with the parameters of the trait R5. In this stage of mass production of concrete blocks manufactured with 5% incorporation of dry polishing sludge, the analysis was carried out seeking comparison with the reference mix and the blocks met the normative physical requirements, such as: water absorption, liquid area, dimensional analysis, void ratio and specific mass. And with the incorporation process, it contributed to the reduction in CO2 emissions and the reduction with operating costs oriented to the incineration process. In view of this, with the implementation of the work, there is an estimate of savings of more than R$ 150,000.00/year in the sum of the generating company, in addition to the reduction in the emission of over 1 ton/year in the emission of C02.