Diseño y construcción de un BIORREACTOR anaerobio en fase líquida para tratar aguas residuales de curtiembre

Abstract

A liquid phase fed batch anaerobic bioreactor was designed and constructed for the treatment of tannery wastewater in the Biotechnology laboratory of the Science Faculty of the Escuela Superior Politécnica de Chimborazo. The methods used in this work were inductive and deductive. In the inductive methods, calculations were developed by means of pre-established formulas to know the dimensions of the fermenter as well as of the liner, also laboratory analyses were developed allowing us to know parameters such as Chemical Oxygen Demand, trivalent chromium, acidity and total coliforms. The treatment was carried out for 4 weeks using a bacterial mix of swine manure, goat manure and whey with an agitation of 90 revolutions per minute. In terms of deductive methods, the positive influence of bioreactors for treating industrial wastewater was investigated at the Latin American level. The cylindrical bioreactor was built in AISI 304 stainless steel, it has an external jacket that maintains a suitable environment using a submersible heater, sensors to measure pH and temperature, height 25 cm, volume 6 L, diameter 20 cm, motor for agitation of 0.5 hp plus a variator. Regarding the results of the treatment, we found initial values of trivalent chromium and Chemical Oxygen Demand 2613.27 mg/L and 7450 mg/L respectively, while the final values were 131.70 mg/L for trivalent chromium and 10100 mg/L for Chemical Oxygen Demand. Based on the results obtained with respect to the design and construction of the bioreactor, we conclude that both its operation and its characteristics are adequate to be used as an instrument in laboratory practices. Regarding the remediation process, we concluded that the efficiency was 60% with respect to trivalent chromium. We recommend that students who use the reactor to separate heavy metals present in wastewater use sulforeducing bacteria, previously isolated, as a culture medium to obtain a better efficiency in the process.