Sulfate reduction behavior in pressure-bearing leachate saturated zone
Lifang Hu , Dongsheng Shen , Haomin Zhou , Zhiyuan Jin , Wenyi Yang , Manting Ci , Yuyang Long
DOI:10.1016/j.jes.2022.04.032
Received February 06, 2022,Revised , Accepted April 26, 2022, Available online May 04, 2022
Volume 35,2023,Pages 545-555
Attention should be paid to the sulfate reduction behavior in a pressure-bearing leachate saturated zone. In this study, within the relative pressure range of 0–0.6 MPa, the ambient temperature with the highest sulfate reduction rate of 50°C was selected to explore the difference in sulfate reduction behavior in a pressure-bearing leachate saturated zone. The results showed that the sulfate reduction rate might further increase with an increase in pressure; however, owing to the effect of pressure increase, the generated hydrogen sulfide (H2S) could not be released on time, thereby decreasing its highest concentration by approximately 85%, and the duration extended to about two times that of the atmospheric pressure. Microbial community structure and functional gene abundance analyses showed that the community distribution of sulfate-reducing bacteria was significantly affected by pressure conditions, and there was a negative correlation between disulfide reductase B (dsrB) gene abundance and H2S release rate. Other sulfate reduction processes that do not require disulfide reductase A (dsrA) and dsrB genes may be the key pathways affecting the sulfate reduction rate in the pressure-bearing leachate saturated zone. This study improves the understanding of sulfate reduction in landfills as well as provides a theoretical basis for the operation and management of landfills.
