Tratamento de efluente de água/óleo por adsorção em um setor de lavagem de peças automotiva em EVA, carvão ativado e produto comercial à base de fibras vegetais

Abstract

The washing process of vehicles parts is an activity that requires elevated volumes of water and generates wastewaters with turbidity, chemical oxygen demand (COD) and high oil and grease content, what grants it a high polluter potential. Knowingly, the separation tanks of water and oil available in the market doesn’t have the efficiency to reach the parameters required by the brazilian legislation. Thus, the potentiality of the use of different adsorbents in the process of treatment of wastewaters from the washing of automotive parts was analysed taking into consideration, mainly, the necessary amount of every adsorbent and duration of the contact. For this to happen, the effect of the adsorbents was studied considering the oil and grease parameters obtained. The adsorbents used were: EVA, granular activated carbon and a commercial product based on organic fibers. The 150ml wastewaters samples were treated with different doses of the above-mentioned adsorbents (0,275 g, 7,012 g e 13,750 g) under agitation to obtain different durations of contact (5, 77,5 e 150 minutes). The entire experiment was made using laboratory experiment. The results show that the wastewaters originated by the mechanical workshop doesn't reach the parameters defined in the legislation only with the separation tanks of water and oil treatment. The point with minor activated carbon mass and duration of contact doesn't show satisfactory results. The EVA has proved itself an interesting adsorbent for oil and grease with adsorption above 90%. The commercial product reached the maximum efficiency in the remotion on all treatments.