Quebra da emulsão óleo-água de fluído de corte degradado

Abstract

The metalworking sector is a very important activity for the national economy. However the machining activities of parts depend on the use of cutting fluids, which after use become hazardous environmental liabilities. In this context, the present work had the objective of breaking the emulsion of the degraded cutting fluids, of the emulsionable type, and the analysis of the aqueous phase obtained. The influence of the pH, the concentration of Calcium Chloride and Magnesium Chloride was evaluated in order to perform the emulsion breakdown, using the statistical design of the Rotational Central Compound (DCCR) in 45 tests. The results were statistically analyzed with significance level of 5% and, through the obtained response surfaces, the optimum point of the studied variables could be located. It was shown that the best results were those with 73.5 g / L addition of Calcium Chloride and pH 13. The use of Magnesium Chloride did not present satisfactory results. Due to the great use of Calcium Chloride and Magnesium Chloride in the samples, the aqueous phase obtained the three best results presented high alkalinity and hardness, although the pH has reduced. Analyzing the toxicity of crude effluent and aqueous phases, inhibition of root growth of Allium cepa ranging from 71.3% to 88.6% is observed, also due to the high salt concentrations.