Design of a UASB reactor as second stage of an efficient system for the treatment of pig wastes (Original)

Abstract

Anaerobic digestion (AD) is an effective technique to treat pig wastes; however, liquid effluents from low-rate anaerobic biodigesters still exhibit high levels of contamination, which can be efficiently treated in a high-rate reactor such as UASB reactors. The organic pollutant load of the liquid effluent from the anaerobic biodigester has values of approximately 1.0 kg / m3, which are highly polluting and have the potential to obtain high volumes of biogas. As a second step of an efficient pig waste treatment system for the Pedregales farm, the construction of an UASB anaerobic reactor of 38,4 m³ is proposed, which would achieve pollutant removal efficiencies greater than 76% and a biogas production of approximately 17,9 m³ d^-1. The combination of an anaerobic biodigester followed by an advanced UASB reactor will allow high efficiencies of pollutant removal and high biogas production, which modifies the current paradigm of treatment of pig wastes in Cuba.