Biochar from bovine manure as a sustainable additive to improve the anaerobic digestion of cheese whey

The cheese industry generates pure cheese whey (CWP) and bovine manure, which have high organic matter contents that, when disposed directly into the environment, can create severe environmental challenges. These impacts can be counteracted by anaerobic digestion (AD); however, the direct AD of CWP is inhibited (163.1 mL CH₄ g⁻¹VS_add). One way to avoid the inhibition of AD is to add biochar. Therefore, this study aimed to evaluate the effects of bovine manure biochar (0–2 g_biochar g⁻¹VS_substrate) on CWP methane production by testing the biochemical methane potential (BMP) of the CWP. The BMP of the CWP with 2 g_biochar g⁻¹VS_substrate was 358.4 mL CH₄ g⁻¹ VS_add. Bovine manure biochar was found to contribute to the stability of the AD process. The findings of our study demonstrate the energetic and economic viability of treating waste that possess characteristics like those of CWP using additives, such as biochar from bovine manure.