Performance and microbial ecology of a nitritation sequencing batch reactor treating high-strength ammonia wastewater

Abstract

The partial nitrification (PN) performance and the microbial community variations were evaluated in a sequencing batch reactor (SBR) for 172 days, with the stepwise elevation of ammonium concentration. Free ammonia (FA) and low dissolved oxygen inhibition of nitrite-oxidized bacteria (NOB) were used to achieve nitritation in the SBR. During the 172 days operation, the nitrogen loading rate of the SBR was finally raised to 3.6 kg N/m3/d corresponding the influent ammonium of 1500 mg/L, with the ammonium removal efficiency and nitrite accumulation rate were 94.12% and 83.54%, respectively, indicating that the syntrophic inhibition of FA and low dissolved oxygen contributed substantially to the stable nitrite accumulation. The results of the 16S rRNA high-throughput sequencing revealed that Nitrospira, the only nitrite-oxidizing bacteria in the system, were successively inhibited and eliminated, and the SBR reactor was dominated finally by Nitrosomonas, the ammonium-oxidizing bacteria, which had a relative abundance of 83%, indicating that the Nitrosomonas played the primary roles on the establishment and maintaining of nitritation. Followed by Nitrosomonas, Anaerolineae (7.02%) and Saprospira (1.86%) were the other mainly genera in the biomass.

Microbubble Application to Enhance Hydrogenotrophic Denitrification for Groundwater Treatment

“…Moreover, Firmicutes was reported to be predominant in autotrophic denitrification biocathode and hydrogenotrophic denitrification under thermophilic (30 o C) conditions (Wang et al, 2015;Xiao et al, 2015). Bacteroidetes was found to be dominant in prior nitritation and partial nitritation processes (Chen et al, 2016). From the present study, it is demonstrated that the microorganisms in both reactors were detected in the denitrification and the microorganisms could use hydrogen gas as the electron donor for nitrate removal.…”

Effect of HRTs on COD and Nutrient Removal in Sequencing Batch Reactor (SBR) Process

“…wastewater treatment. It is an attractive technology to treat this type of pollution due to economic advantages it offers in terms of operation cost and efficiency [8,9]. However, the treatment sites require a great deal of land and are costly to maintain, and the treatment process itself requires a lot of attention.…”

“…However, the treatment sites require a great deal of land and are costly to maintain, and the treatment process itself requires a lot of attention. [8][9][10]. Thus, alternatives have been introduced such as the sequencing batch reactor (SBR).…”

“…The SBR is an activated sludge process that utilizes a fill and draw sequence and can be operated in just one tank [1,6]. It works as an equalization, neutralization and biological treatment and secondary clarifier in a single tank through a timed control sequence, which makes it environmentally friendly technology [8,9]. Operation of SBR consists of four stages, which are fill, react, settle, and draw.…”

Effective removal of ammonia from wastewater using hollow fiber renewal liquid membrane

“…7,8 In recent years, various methods, such as breakpoint chlorination method, [9][10][11] ion exchange adsorption, 12 biological method, 13,14 and chemical precipitation, 15 have been developed for treatment of ammonia wastewater. These methods have advantages, but there are still some flaws, [16][17][18][19][20][21] such as high cost, producing secondary pollution, low removal efficiency, long processing time, high energy consumption, and limited treatment capacity. Therefore, it is of vital significance to develop a new treatment technology for ammonia wastewater.…”