The beneficial role of intermediate clarification in a novel MBR based process for biological nitrogen and phosphorus removal

This study combined the IA craft, and the goal is to achieve aerobic, anoxic and even anaerobic alternating cycles in the same reactor to enhance biological nitrogen and phosphorus removal. At present, there are many studies on the IA process, but less research on the IAMBBR craft. The IAMBBR craft combines intermittent aeration with a biofilm process, which can further improve the processing capacity of a continuous-flow biofilm reactor. Therefore, it is necessary to conduct a detailed study of the IAMBBR craft. In addition, the exposure time ratio is an important parameter for the operation of the IA craft. By adjusting the exposure time ratio, the DO concentration in the reactor can be controlled, which affects the operation effect of the reactor. Therefore, this chapter mainly explores the effect of exposure time ratio on the operating effect of IAMBBR. Six operating stages were connected: the ratio of CA and exposure time are 3h/3h, 1h/1h, 30min/30min, 15min/15min, and 5min/5min, respectively, to study the removal effect of pollutants.

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Development of MBR with reduced operational and maintenance costs

Water Science & Technology ◽

10.2166/wst.2006.075 ◽

2006 ◽

Vol 53 (3) ◽

pp. 53-60 ◽

Cited By ~ 3

Author(s):

Y. Annaka ◽

Y. Hamamoto ◽

M. Akatsu ◽

K. Maruyama ◽

S. Oota ◽

...

Keyword(s):

Phosphorus Removal ◽

Power Demand ◽

Biological Phosphorus Removal ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Membrane Cleaning ◽

Sludge Disposal ◽

Air Supply ◽

Biological Nitrogen ◽

Biological Phosphorus

To reduce MBR O&M costs, a new MBR process that conducts efficient simultaneous biological nitrogen and phosphorus removal (BNR) was developed. In the development of this process, various approaches were taken, including reduction of power demand, chemical consumption and sludge disposal costs. To address power demand reductions, air supply requirements for membrane cleaning were reduced. The process adopted an improved membrane that requires less air for cleaning than conventional membranes. It also introduced cyclic aeration, which alternately supplies washing air to the two series of membrane units. Adoption of biological phosphorus removal eliminated chemical costs for phosphorus removal and contributed to the reduction of sludge disposal costs. By combining these technologies, compared to conventional MBR processes, an approximately 27% reduction in O&M costs was achieved.

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Co-optimisation of phosphorus and nitrogen removal in stormwater biofilters: the role of filter media, vegetation and saturated zone

Water Science & Technology ◽

10.2166/wst.2014.117 ◽

2014 ◽

Vol 69 (9) ◽

pp. 1961-1969 ◽

Cited By ~ 23

Author(s):

Bonnie J. Glaister ◽

Tim D. Fletcher ◽

Perran L. M. Cook ◽

Belinda E. Hatt

Keyword(s):

Water Quality ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Saturated Zone ◽

Filter Media ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Quality Guidelines ◽

The Impact

Biofilters have been shown to effectively treat stormwater and achieve nutrient load reduction targets. However, effluent concentrations of nitrogen and phosphorus typically exceed environmental targets for receiving water protection. This study investigates the role of filter media, vegetation and a saturated zone (SZ) in achieving co-optimised nitrogen and phosphorus removal in biofilters. Twenty biofilter columns were monitored over a 12-month period of dosing with semi-synthetic stormwater. The frequency of dosing was altered seasonally to examine the impact of hydrologic variability. Very good nutrient removal (90% total phosphorus, 89% total nitrogen) could be achieved by incorporating vegetation, an SZ and Skye sand, a naturally occurring iron-rich filter medium. This design maintained nutrient removal at or below water quality guideline concentrations throughout the experiment, demonstrating resilience to wetting–drying fluctuations. The results also highlighted the benefit of including an SZ to maintain treatment performance over extended dry periods. These findings represent progress towards designing biofilters which co-optimise nitrogen and phosphorus removal and comply with water quality guidelines.

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Biological nitrogen and phosphorus removal in UCT-type MBR process

Water Science & Technology ◽

10.2166/wst.2009.242 ◽

2009 ◽

Vol 59 (11) ◽

pp. 2093-2099 ◽

Cited By ~ 19

Author(s):

H. Lee ◽

J. Han ◽

Z. Yun

Keyword(s):

Phosphorus Removal ◽

P Uptake ◽

Biological Nutrient Removal ◽

Anoxic Zone ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Nitrate Inhibition ◽

Biological Nitrogen ◽

P Removal ◽

Production Characteristics

A lab-scale UCT-type membrane bio-reactor (MBR) was operated for biological nitrogen (N) and phosphorus (P) removal simultaneously. In order to examine biological nutrient removal (BNR) characteristics of MBR, the lab unit was fed with a synthetic strong and weak wastewater. With strong wastewater, a simultaneous removal of N and P was achieved while application of weak wastewater resulted in a decrease of both N and P removal. Recycled nitrate due to the limited organic in weak wastewater operation probably caused a nitrate inhibition in anaerobic zone. In step feed modification with weak wastewater, both N and P removal capability recovered in the system, indicating that the allocation of COD for denitrification at anoxic zone was a key to increase the biological P removal. In addition, the analysis on the specific P uptake rate in anoxic zone demonstrated that denitrifying phosphorus accumulating organism (dPAO) played an important role to remove up to 40% of P along with N. The sludge production characteristics of UCT-type MBR were similar to ordinary activated sludge with BNR capability.

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