Performance of an Anaerobic Reactor Treating Poultry Abattoir Wastewater with High Fat Content After Enzymatic Hydrolysis

Abstract

Abstract Effects of a lipase-rich solid enzymatic preparation produced by the fungus Penicillium restrictum in solid-state fermentation were evaluated in up-flow anaerobic sludge blanket reactors treating poultry slaughterhouse wastewater with 800 mg oil and grease (O&G)/L. Reactors operated at 30°C under two organic load rates (3.9 and 7.3 kg chemical oxygen demand [COD]/m3·day). The reactor fed with previously hydrolyzed wastewater showed higher methane production values, as well as high COD removal levels (367 and 882 mL CH4/day and 90.4% and 93.5% at 1st and 2nd regimen, respectively). In the reactor fed with raw wastewater, 178 and 642 mL CH4/day and 89.8% and 91.0% of COD removal were verified at 1st and 2nd regimen, respectively. Although differences are not so significant in terms of COD removal and biogas production, the greatest impact on the implementation of solid enzymatic preparation in the prehydrolysis step was the better operating conditions: in the control reactor, frequent episodes of c...