Comparison of Degradation of Lignin-containing Wastewaters in the Presence of Different Microbial Consortia

Abstract

Lignin-containing wastewater treatment by different microbial consortia were studied in this research. The special microbial consortia (J-6 and J-1) obtained from decayed wooden relics were selected. The bacteria of original microbial consortium J-6 mainly included Shinella , Cupriavidus and Bosea . The bacteria of original microbial consortium J-1 mainly included Serratia and Yersinia . The fungi of J-6 and J-1 were dominated by Saccharomycetales. The performances of two microbial consortia in wastewater treatment were compared, and the changes in community structure were analyzed to study the relationship between microbial consortium structure and degradation efficiency. For the treatment of model Chinese medicine wastewater, the optimal degradation conditions were treatment temperature of 30 °C, initial pH of 7, dissolved oxygen of 2 mg L –1 , and treatment time of 96 h. The COD (Chemical Oxygen Demand) removal efficiency reached 95.25 % by J-1. For the treatment of model papermaking wastewater, the optimal degradation conditions were treatment temperature of 30 °C, pH of 5, dissolved oxygen of 3 mg L –1 , nitrogen source concentration of 0.1 g L –1 , and treatment time of 120 h. The COD removal efficiency reached 86.8 % by J-6. Bacteria played a significant role in the degradation of lignin-containing wastewater, and the bacterial consortium abundance may promote the degradation of organic substances in the wastewater. The dominant strains were different in Chinese medicine wastewater and paper-making wastewater systems. The correlation between microorganisms and the difference in the abundance of bacteria groups may be the reason for the different performances of the two microbial consortia in treating different lignin-containing wastewaters.