The anaerobic biodegradability of paper mill wastewater constituents

The biodegradability of ten paper mill wastewater constituents under methanogenic conditions was evaluated in this study. The compounds studied included wood resin constituents and low molecular weight lignin derivatives. Biodegradation was assessed in batch bioassays inoculated with anaerobic granular sludge at 30 ± 2°C. The assays were supplied with low concentrations of the test chemicals (35–200 mg 1⁻¹) to prevent methanogenic inhibition. The long chain fatty acids, oleic and linoleic acid, were readily biodegradable under anaerobic conditions. Guaiacol was also mineralized after a 40 days lag period. However, no indication of methanogenic degradation was obtained with eugenol, benzene, the resin acids (abietic and dehydroabietic acid), the volatile terpenes (pinene and limonene) and the unsaturated hydrocarbon squalene.