Work

Variation in bacterial communities during landfill leachate treatment by a modified sequencing batch reactor (SBR)

Year: 2019

Type: article

Abstract: ABSTRACT A modified sequencing batch reactor, which adds a pre-anoxic phase before the aeration phase, was used to treat toxic landfill leachate, and high-throughput sequencing technology used to study how the classification, distribution and abundance of functional bacterial communities varies during system operation. The system operation results are as follows: in the full load steady operation period (II), influent/effluent chemical oxygen demand (COD) and total nitrogen (TN) concentrations were approximately 6,421/645 and 1,210/19 mg/L, respectively; TN and COD removal rates of the system were above 93% and 87%, respectively. The bacterial community structure of the system is as follows: when compared with the bacterial community structure of the inoculation sludge, the final dominant phyla of the system were Proteobacteria (49.4%) and Bacteroidetes (36.5%), while β-Proteobacteria (30.05%) and α-Proteobacteria (16.4%) under Proteobacteria were the two dominant classes in the full load steady operation period (II). Nitrosomonas (22.56%) was the main ammonia-oxidizing bacteria within β-Proteobacteria. The bacterial community associated with endogenous denitrification included Paracoccus (α-Proteobacteria, 19.15%), Thauera (β-Proteobacteria, 8.36%), and Truepera (4.96%). Paracoccus and Thauera were endogenous denitrifying bacteria that could transform organic matter into polyhydroxyalkanoates (PHA) and use PHA to remove nitrogen under anaerobic conditions, and Truepera could resist leachate toxicity.

Source: Desalination and Water Treatment

DOI: 10.5004/dwt.2019.23500