Anaerobic digestion (AD) is a process used to convert animal and agro-industrial wastes to organic fertilizers. Since digester effluents are used as for cropland applications, we are interested to find out whether the quality of these organic fertilizers are impacted by the AD process. In addition, few studies have investigated the performance of AD in field conditions. In this study, we monitored the performance of three operational AD systems for two years. These three systems have different retention times (9, 12 and 34 days), that is how long the waste materials stay in the digester. We collected influent and effluent samples every two months and analyzed for pH, nutrients and metals. We found that the two shorter retention systems slightly decreased effluent pH while the long retention system significantly increased the effluent pH, i.e., by 1.8 unit. The 34-day retention system also removed more solids and increased ammonium-nitrogen in the effluent. We found no significant changes in the metals that we analyzed. These findings can assist in developing strategies for cleaner production using AD in an environmentally sustainable manner.

This dataset is associated with the following publication: Zhang, X., I. Lopes, J. Ni, Y. Yuan, C. Huang, D.R. Smith, I. Chaubey, and S. Wu. Long-term performance of three mesophilic anaerobic digesters to convert animal and agro-industrial wastes into organic fertilizer. JOURNAL OF CLEANER PRODUCTION. Elsevier Science Ltd, New York, NY, USA, 307: 127271, (2021).