Effects of side-stream, low temperature phosphorus recovery on the performance of anaerobic/anoxic/oxic systems integrated with sludge pretreatment

Abstract In this study, phosphate-rich supernatant at the end of anaerobic phase was extracted by a certain side-stream ratio for chemical precipitation to investigate the optimal conditions for phosphorus recovery. The effect of side-stream reaction on the performance of the mainstream enhanced biological phosphorus removal (EBPR) system was also explored. The experiment was carried out in a sequencing batch reactor (SBR) operated in an alternating anaerobic/aerobic mode with dissolved oxygen controlled at 1.0 mg · L−1. The results showed that the optimum magnesium source,temperature, stirring speed and reaction equilibrium time for side-stream phosphorus recovery were: MgCl2 · 6H2O, 25 °C, 150 rpm and 20 min, respectively. It was also observed that the average phosphorus removal efficiency of the mainstream system maintained as high as 90.7% during the side-stream extraction period despite insufficient time for phosphate uptake under limited dissolved oxygen condition and phosphate deprivation of polyphosphate-accumulating organisms (PAOs). Besides, the sludge settling performance of the mainstream EBPR system decreased with no sludge loss. Afterwards, phosphorus removal and sludge settling performance were restored with dismissing side-stream phosphorus recovery. This study suggested that side-stream extraction of anaerobic supernatant from a mainstream EBPR subjected to low dissolved oxygen conditions for chemical phosphorus recovery was feasible and environmentally friendly.

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Effect of side-stream phosphorus recovery on biological phosphorus removal performance investigated by chemical and microbial analyses in a novel BNR-IC process

Water Science & Technology ◽

10.2166/wst.2014.351 ◽

2014 ◽

Vol 70 (9) ◽

pp. 1441-1447 ◽

Cited By ~ 1

Author(s):

H. M. Zou ◽

X. W. Lu ◽

T. Li

Keyword(s):

Microbial Community ◽

Denaturing Gradient Gel Electrophoresis ◽

Phosphorus Recovery ◽

Biological Phosphorus Removal ◽

Side Stream ◽

Negative Effect ◽

Gradient Gel Electrophoresis ◽

P Recovery ◽

Biological Phosphorus ◽

P Removal

The aim of this study was to assess the effect of side-stream ratio (SSR) on performance of phosphorus (P) removal and recovery in a novel process linking biological nutrients removal (BNR) and induced crystallization (IC). Results showed that P removal efficiency was significantly enhanced when given an appropriate SSR, resulting in effluent P concentrations decreasing from 0.75 to 0.39 mg/L with an increase of SSR from 0 to 35%, where a maximum of 7.19 mg/L P recovery amount was obtained at 35% of SSR. Increasing the SSR can favor the P recovery, while an excessively high SSR (more than 35%) would have a negative effect on the subsequent biological P removal in the BNR-IC system. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis showed that in total, 11 DGGE bands of highest species richness were visually detected and significant changes in microbial community structure were found, with SSR variations ranging from 0 to 55%. Moreover, an increase in SSR can cause an increase in microbial community biodiversity; where microbial populations correspond to the 11 bands, they were generally classified into five different phyla or classes (Beta-, Gamma-, and Deltaproteobacteria, as well as Clostridia and Flavobacteria) based on the evolutionary tree analysis.

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Nutrient removal and phosphorus recovery performance of an anaerobic side-stream extraction based enhanced biological phosphorus removal subjected to low dissolved oxygen

Journal of Water Process Engineering ◽

10.1016/j.jwpe.2020.101861 ◽

2021 ◽

Vol 42 ◽

pp. 101861

Author(s):

Xiao-jun Yu ◽

Wen-qing Tian ◽

Ying Deng ◽

Yu-qi Cai ◽

Ya-e Wang ◽

...

Keyword(s):

Dissolved Oxygen ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Phosphorus Recovery ◽

Enhanced Biological Phosphorus Removal ◽

Biological Phosphorus Removal ◽

Low Dissolved Oxygen ◽

Side Stream ◽

Recovery Performance ◽

Biological Phosphorus

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Effects of side-stream operation on the mainstream biological phosphorus metabolic pathway for phosphorus recovery: Simulation by an extended ASM2d model

Journal of Environmental Management ◽

10.1016/j.jenvman.2021.112819 ◽

2021 ◽

Vol 293 ◽

pp. 112819

Author(s):

Xuehui Zu ◽

Jun Nan ◽

Zhenbei Wang ◽

Qiliang Xiao ◽

Bohan Liu

Keyword(s):

Metabolic Pathway ◽

Phosphorus Recovery ◽

Side Stream ◽

Recovery Simulation ◽

Biological Phosphorus

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Effect of low temperature thermochemical pretreatment on sludge reduction potential of membrane bioreactor treating primary treated dairy wastewater

Water Quality Research Journal ◽

10.2166/wqrjc.2011.026 ◽

2011 ◽

Vol 46 (4) ◽

pp. 312-320 ◽

Cited By ~ 13

Author(s):

J. Rajesh Banu ◽

S. Kaliappan ◽

Adish Kumar ◽

Ick Tae Yeom ◽

Do Khac Uan

Keyword(s):

Low Temperature ◽

Membrane Bioreactor ◽

Thermochemical Treatment ◽

Dairy Wastewater ◽

Transmembrane Pressure ◽

Sludge Reduction ◽

Thermochemical Pretreatment ◽

Submerged Membrane Bioreactor ◽

Sludge Digestion ◽

Sludge Pretreatment

In this present study, an aerobic submerged membrane bioreactor (MBR) was used to study the effect of thermochemical pretreatment on the efficiency of sludge reduction. For this purpose, two MBRs were fabricated. Between the two MBRs, one acted as a control reactor (CMBR) and the other acted as an experimental reactor (EMBR). The MBRs were operated with a mixed liquor suspended solids (MLSS) concentration in the range of 6,800–7,200 mg/L for a period of 160 days. In the EMBR, part of the MLSS was withdrawn at a ratio of 1% of Q and was pretreated by low temperature thermochemical treatment. The sludge pretreatment was carried out at 60 °C and an alkali dosage in the range of 0.49 to 0.56 mg NaOH/mg MLSS. During the pretreatment, 42% of COD solubilization and 22% of SS reduction were observed. The pretreated sludge was returned to the reactor for further degradation where it was found to be 42% reduced. During the 160 days of reactor operation, both of the MBRs maintained a relatively constant transmembrane pressure. The sludge digestion does not have any impact on the COD removal efficiency of the reactor.

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