Study of the Operation of a Continuous Modular Bioreactor Used for Treatment of Wastewater from a Recycling Industry of by-Products from Slaughterhouses

The objective of this paper was to present the operational performance of a bioreactor’s technology for treating wastewater from a recycling industry of by-products from slaughterhouses. In addition, it contributes to overcome the main disadvantages of treatment using Australian pond systems. The modular bioreactor described in this work consists of an alternative and innovative equipment that operates continuously on an industrial scale, which enables the treatment of liquid waste. The modular bioreactor was constructed of reinforced concrete with dimensions 70 m in length, 1.2 m in width, and 0.6 m in height, with an internal volume of 35,000 L, the process of wastewater degradation alternating between aerobic and anoxic conditions, being predominantly anoxic. The bioreactor was tested in two stages, by using this industrial wastewater. In the first stage, totaling 243 days, a primary effluent was added, consisting of high concentration of pollutants; and in a second stage, totaling 288 days, it was added a biologically pretreated effluent (after an anaerobic post-digestion process). The input-output parameters pH, turbidity, conductivity, temperature, and dissolved oxygen were monitored weekly, while total phosphorus, orthophosphate, total nitrogen, ammonium, nitrite, nitrate, total suspended solids, sedimented solids, oils and greases, COD, BOD, and alkalinity parameters were determined monthly. The bioreactor was promising in terms of pollutant removal efficiency, and partial nitrification may have occurred on a continuous scale in the first stage of the tests.