Research on Removal Effects of Pollutants by the (A/O)4 SBR Process

The staged SBR is the process that divides aeration and sedimentation process of conventional SBR into several stages in time, and operates under the conditions of different stages of anaerobic/oxic/anoxic alternation. The experiment mainly discussed the five-stage SBR with useful volume of 12 L for nitrogen and phosphorous removal of synthetic municipal wastewater in the temperature ranges of 15~30°C. Tests revealed that under the condition of hydraulic retention time (HRT) is 8 hours and sludge retention time (SRT) is 15 day, the removal efficiency of COD, NH3-N, TN and TP can reach to 88.9%, 99.61%, 78.9% and 94.21%. The quality of effluent water is good, and don’t need to add Carbon Source through the experiment.

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Continuing the Development of Municipal Effluent Guidelines for the Northwest Territories

Water Science & Technology ◽

10.2166/wst.1986.0028 ◽

1986 ◽

Vol 18 (2) ◽

pp. 179-184

Author(s):

R. J. Kent

Keyword(s):

Northwest Territories ◽

Removal Efficiency ◽

Municipal Wastewater ◽

Coliform Bacteria ◽

Flow Ratio ◽

Dilution Ratio ◽

Effluent Quality ◽

Municipal Effluent

The background to and the rationale for the Guidelines for Municipal Type Wastewater Discharges in the Northwest Territories is discussed. Particu1ar attention is given to the development of Table 2.1, Effluent Quality of Municipal Wastewater Discharges, which was based upon expected lagoon performance. Also included is a discussion of the flow ratio and dilution ratio concepts. The viability of these concepts was assessed against the available data. It appears that the guidelines misjudged both the number of coliform bacteria in northern raw sewage and the removal efficiency for these organisms in lagoons. It appears unlikely that lagoons can consistently meet the guideline requirements. More information and research is necessary before a complete assessment can be performed.

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Evaluation of a tropical single-cell waste stabilization pond system for irrigation

Water Science & Technology ◽

10.2166/wst.1995.0495 ◽

1995 ◽

Vol 31 (12) ◽

pp. 267-273 ◽

Cited By ~ 4

Author(s):

B. S. O. Ceballos ◽

A. Konig ◽

B. Lomans ◽

A. B. Athayde ◽

H. W. Pearson

Keyword(s):

Single Cell ◽

Removal Efficiency ◽

Retention Time ◽

Hydraulic Retention Time ◽

Full Scale ◽

Waste Stabilization Pond ◽

North East ◽

Helminth Eggs ◽

Waste Stabilization ◽

Better Than

A single full-scale primary facultative pond in Sapé, north-east Brazil was monitored for performance and efficiency. The pond had a hydraulic retention time of 61 days and achieved a 95% BOD5 removal efficiency and had no helminth eggs in the effluent. The effluent failed to meet the WHO faecal coliform guideline for unrestricted irrigation. The pond was dominated by the cyanobacterium Microcystis and gave better than predicted orthophosphate removal. Details of how the system could be simply upgraded utilizing the same land are discussed.

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Effects of the Sludge Retention Time and Carbon Source on Polyhydroxyalkanoate-Storing Biomass Selection under Aerobic-Feast and Anoxic-Famine Conditions

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.1c02973 ◽

2021 ◽

Author(s):

Nicola Frison ◽

Marco Andreolli ◽

Alice Botturi ◽

Silvia Lampis ◽

Francesco Fatone

Keyword(s):

Carbon Source ◽

Retention Time ◽

Sludge Retention Time

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Anaerobic thermophilic digestion of sewage sludge with a thickened sludge recycle

Water Science & Technology ◽

10.2166/wst.2012.783 ◽

2012 ◽

Vol 65 (3) ◽

pp. 403-409 ◽

Cited By ~ 2

Author(s):

A. Ya. Vanyushina ◽

Yu. A. Nikolaev ◽

A. M. Agarev ◽

M. V. Kevbrina ◽

M. N. Kozlov

Keyword(s):

Retention Time ◽

Municipal Wastewater ◽

Hydraulic Retention Time ◽

Biogas Production ◽

Wastewater Sludge ◽

Recycling Process ◽

Digested Sludge ◽

Volatile Solids ◽

Solids Retention ◽

Thermophilic Digestion

The process of anaerobic thermophilic digestion of municipal wastewater sludge with a recycled part of thickened digested sludge, was studied in semi-continuous laboratory digesters. This modified recycling process resulted in increased solids retention time (SRT) with the same hydraulic retention time (HRT) as compared with traditional digestion without recycling. Increased SRT without increasing of HRT resulted in the enhancement of volatile substance reduction by up to 68% in the reactor with the recycling process compared with 34% in a control conventional reactor. Biogas production was intensified from 0.3 L/g of influent volatile solids (VS) in the control reactor up to 0.35 L/g VS. In addition, the recycling process improved the dewatering properties of digested sludge.

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Effect of 200 days' sludge retention time on performance of a pilot scale submerged membrane bioreactor for high strength industrial wastewater treatment

Water Science & Technology ◽

10.2166/wst.2006.362 ◽

2006 ◽

Vol 53 (11) ◽

pp. 269-276 ◽

Cited By ~ 6

Author(s):

C.T. Hay ◽

D.D. Sun ◽

S.L. Khor ◽

J.O. Leckie

Keyword(s):

Retention Time ◽

Industrial Wastewater ◽

Membrane Bioreactor ◽

Hydraulic Retention Time ◽

High Strength ◽

Pilot Scale ◽

Submerged Membrane Bioreactor ◽

Sludge Retention Time ◽

Organic Removal ◽

Sludge Concentration

A high strength industrial wastewater was treated using a pilot scale submerged membrane bioreactor (MBR) at a sludge retention time (SRT) of 200 d. The MBR was operated at a high sludge concentration of 20 g/L and a low F/M ratio of 0.11 during 300 d of operation. It was found that the MBR could achieve COD and TOC overall removal efficiencies at more than 99 and 98% TN removal. The turbidity of the permeate was consistently in the range of 0.123 to 0.136 NTU and colour254 absorbance readings varied from 0.0912 to 0.0962 a.u. cm−1. The sludge concentration was inversely proportional to the hydraulic retention time (HRT), yielded excellent organic removal and extremely low sludge production (0.0016 kgVSS/day).

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Towards high through-put biological treatment of municipal wastewater and enhanced phosphorus recovery using a hybrid microfiltration-forward osmosis membrane bioreactor with hydraulic retention time in sub-hour level

Bioresource Technology ◽

10.1016/j.biortech.2016.07.126 ◽

2016 ◽

Vol 219 ◽

pp. 298-310 ◽

Cited By ~ 24

Author(s):

Guanglei Qiu ◽

Sui Zhang ◽

Divya Shankari Srinivasa Raghavan ◽

Subhabrata Das ◽

Yen-Peng Ting

Keyword(s):

Retention Time ◽

Biological Treatment ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Hydraulic Retention Time ◽

Forward Osmosis ◽

Phosphorus Recovery

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Removal and Transformation of Pollutants in a Two-Line Denitrifying Phosphorus Removal Process Treating Low C/N Municipal Wastewater: Influence of Hydraulic Retention Time

Water Air & Soil Pollution ◽

10.1007/s11270-018-3746-9 ◽

2018 ◽

Vol 229 (3) ◽

Cited By ~ 4

Author(s):

Hongbo Liu ◽

Yangyang Yao ◽

Suyun Xu

Keyword(s):

Retention Time ◽

Phosphorus Removal ◽

Municipal Wastewater ◽

Hydraulic Retention Time ◽

Denitrifying Phosphorus Removal ◽

Removal Process

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Treatment Of Tofu Industry Wastewater Using Bioreactor Anaerobic-Aerobic And Bioball As Media With Variation Of Hidraulic Retention Time

REAKTOR ◽

10.14710/reaktor.19.1.18-25 ◽

2019 ◽

Vol 19 (1) ◽

pp. 18-25

Author(s):

Ariani Dwi Astuti ◽

Dewi Intania Ayu

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Retention Time ◽

Hydraulic Retention Time ◽

Negative Impact ◽

Low Cost ◽

Industrial Effluent ◽

Organic Loading Rate ◽

High Concentration ◽

Small Industries

Tofu which is made by grinding soy bean, generates huge amount of wastewater and thus considered as one of the most polluted food-industrial effluent owing to its high values of organic contents. The small industries of tofu preparation process release the wastewater directly into the water body without being treated first. Prior to discharge this wastewater into the waterbody, the wastewater must be treated to reduce the possibility of negative impact and the contamination of the waterbody. For these small industries, the best alternative of wastewater treatment is one which has the following criteria: easy in operation, low cost operation, low volumes of sludge produced, and can be used in high concentration wastewater. In this research, bioreactor anaerobic-aerobic with media bioball is used. The highest removal efficiency of COD took place in anaerobic zones. Bioreactors were operated with the variations of retention time at 24 hours, 18 hours, and 12 hours. The COD removal efficiency for Hydraulic Retention Time (HRT) of 24 hours, 18 hours and 12 hours were found 90.3% (organic loading rate is 15.1 kg COD/m3.day), 84.4% and 76.3% respectively. The experiment showed that the longer of the hydraulic retention time (HRT), the higher the removal efficiency could be achieved. These occurred because a longer HRT will extend the contact time between wastewater and microorganisms attached. Therefore, microorganisms have a longer time to degrade organic matter in wastewater. Although the removal efficiency in these three-HRT was found high, the effluent of the reactor was still above the effluent standard based on regulation of Ministry of Environmental Permen LH No. 5/2014. Kinetics using Eckenfelder Equation results R2 equal to 0.9991, n equal to 0.293 and K equivalent to 7.3577 mg/L. Keywords: tofu wastewater, anaerobe, aerobe, bioball, wastewater, treatment, attached growth

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The Phosphorous Removal after Anaerobic Stages of Different Durations and under Different Organic Loadings in the Reversed A2/O Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.183-185.1195 ◽

2011 ◽

Vol 183-185 ◽

pp. 1195-1199

Author(s):

Feng Zhang ◽

Chang Qing Liu ◽

Zhong Qiao ◽

Gong Fa Chang ◽

Yan Hui Qu ◽

...

Keyword(s):

Reaction Time ◽

Retention Time ◽

Uptake Rate ◽

Hydraulic Retention Time ◽

Carbon Sources ◽

Phosphorus Uptake ◽

Organic Loading ◽

Phosphorous Removal ◽

Available Carbon ◽

Anaerobic Reaction

The phosphorous removal behaviors under higher and moderate organic loading and after different durations of anaerobic stages were studied in the reversed A2/O process. Under both loading, the length of anaerobic stages did not significantly affect the subsequent aerobic phosphorus uptake efficiencies. Under higher loading, the available carbon sources are adequate, prolonging anaerobic stages led to more released phosphorus from phosphate accumulating organisms (PAOs). However, the phosphorus uptake rate in aerobic stage was almost the same as that of lower loading. At an anaerobic reaction time of 2.0 h, the corresponding specific aerobic phosphorus uptake rate achieved the highest value (6.13 mg/(L.h)). These results can help to determine the anaerobic hydraulic retention time in the reversed A2/O process.

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