Anaerobic digestion of blood serum water integrated in a valorization process of the bovine blood treatment

Abstract

The present work aims to analyze the valorization of blood (Category 3 animal by-products). In this study, for the first time, blood serum water, obtained after a sterilization process and a solid/liquid separation unit, has been utilized as energy rich input material for anaerobic digestion. The performance of an up-flow anaerobic filter (UAF) for treating bovine blood serum water under mesophilic conditions was investigated. The reactor was loaded up to an organic loading rate of 2.5 kg m−3 d−1 of total COD, achieving total and soluble COD removal efficiencies of 90% and 92%, respectively. A maximum biogas yield of 0.56 m3 kg−1 of removed total COD was measured.According to the modified Stover-Kincannon kinetic model, maximum removal rate constant, Umax, and saturation value constant, KB, values were estimated as 18.8 g L−1 d−1 and 18.5 g L−1 d−1 for blood serum water, respectively. As the model gave high correlation coefficients (R2 = 97%), it could be used in both designing and predicting the behaviour of the UAF.