The Role of Agricultural Wastes-Peanut Shells in Enhancing Algae-Bacteria Consortia Performance for Efficient Wastewater Treatment

Carbon source limitation is a critical factor restricting the treatment efficiency of domestic wastewater by algae-bacteria consortia. Using agricultural waste as an external carbon source to enhance purification performance holds significant potential. This study investigated the effects of peanut shell powder (PSP) on wastewater treatment in algae-bacteria consortia. The results demonstrated that the optimal PSP dosage (2 mg/L) improved the removal efficiencies of TN, TP, and COD by 29.6%, 40.9%, and 18.7%, respectively. In contrast, excessive PSP reduced the removal performance. The primary mechanism by which PSP influenced the algae-bacteria consortia involved changes in microbial biomass and community structure. An optimal PSP dosage promoted the proliferation of the dominant algal species, Chlorella, enhanced photosynthetic activity, and increased the relative abundance of Rhodanobacter, known for its effective degradation of benzene compounds. Conversely, excessive PSP caused microbial cell rupture, inhibited Chlorella growth and photosynthesis, and elevated the abundance of Microcystis and Brevundimonas, which pose significant health risks. In conclusion, PSP can improve effluent quality and safety in algae-bacteria consortia, which represents a green, economical pathway for optimizing wastewater treatment processes.