Influência de sólidos suspensos voláteis na biodegradabilidade aérobia do efluente da produção de ácido caproico

Abstract

The production of caproic acid is currently very desirable as it enables the manufacturing of important products from organic waste materials, much of which is used for commercial, industrial and agricultural activities. The production of caproic acid from the substrates ethanol and acetic acid generates a new effluent with unknown characteristics. It will need to be adequately treated before being released into the water body in order to avoid environmental and social problems that directly affect the quality of life. Thus, the main objective of this research was to verify the influence of the different volatile suspended solid concentrations on the aerobic biodegradability of the caproic acid production effluent. The assembly and operation of the system was determined from the hydraulic retention time (HRT), with the best time being five days. To accomplish this, four aerobic batch reactors were assembled in duplicate with bench-scale air compressors and prolonged aeration. Different concentrations of Volatile Suspended Solids 2500, 3000, 3500, 4000 (mg / L) were tested to verify the best manner to remove organic matter, having as inoculum the sludge from the treatment of brewery effluent and residual glycerol. In this context, all reactors had COD removal efficiency averaging 97%. The removal efficiency of orthophosphate ranged from 81% to 95% on average. Thus, the proposed system in the experimental conditions was suitable for the aerobic removal of organic matter from the effluent of the caproic acid production with the VSS concentration of 3500 and 4000 mg / L being the most efficient for this process.