Enhanced primary treatment during wet weather flow using ferrate as a coagulant, coagulant aid and disinfectant

Abstract Under the Government of Canada's Great Lakes Program, the Great Lakes Sustainability Fund and its predecessor programs (the Great Lakes Cleanup Fund and the Great Lakes 2000 Cleanup Fund) were established to implement cleanup actions and strategies that would contribute to the restoration of beneficial uses in environmentally degraded areas (known as Areas of Concern) in the Great Lakes basin. The Great Lakes Sustainability Fund is administered by Environment Canada on behalf of eight Government of Canada departments. Contributing to impaired beneficial uses are municipal wastewaters generated from the urban centres in the Great Lakes Areas of Concern. These municipal wastewaters include treated sewage and wetweather discharges of combined sewer overflows and stormwater runoff. This paper provides an overview of the Municipal Wastewater Program of the federal government's Great Lakes Sustainability Fund and highlights the progress made to date under the program towards wet-weather flow management and the Program's role in developing and demonstrating sustainable approaches and technologies in the Great Lakes Areas of Concern.

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Origins and characteristics of urban wet weather pollution in combined sewer systems: the experimental urban catchment “Le Marais” in Paris

Water Science & Technology ◽

10.2166/wst.1998.0010 ◽

1998 ◽

Vol 37 (1) ◽

pp. 35-43 ◽

Cited By ~ 13

Author(s):

Marie-Christine Gromaire-Mertz ◽

Ghassan Chebbo ◽

Mohamed Saad

Keyword(s):

Waste Water ◽

Sewer System ◽

Urban Catchment ◽

Rainfall Events ◽

Sources Of Pollution ◽

Sewer Systems ◽

Combined Sewer ◽

Wet Weather ◽

Wet Weather Flow ◽

Different Sources

An experimental urban catchment has been created in the centre of Paris, in order to obtain a description of the pollution of urban wet weather flows at different levels of the combined sewer system, and to estimate the contribution of runoff, waste water and sewer sediments to this pollution. Twenty-two rainfall events were studied from May to October 1996. Dry weather flow was monitored for one week. Roof, street and yard runoff, total flow at the catchment outlet and waste water were analysed for SS, VSS, COD and BOD5, on both total and dissolved fraction. Results show an evolution in the characteristics of wet weather flow from up to downstream: concentrations increase from the catchment entry to the outlet, as well as the proportion of particle-bound pollutants and the part of organic matter. A first evaluation of the different sources of pollution establishes that a major part of wet weather flow pollution originates from inside the combined sewer, probably through erosion of sewer sediments.

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Accurate Wet-Weather Flow Characterization and Dynamic Modeling Help Optimize Treatment Designs and Operations

Proceedings of the Water Environment Federation ◽

10.2175/193864712811726095 ◽

2012 ◽

Vol 2012 (14) ◽

pp. 2339-2357

Author(s):

J. D. Fitzpatrick ◽

N. J. Tetrick ◽

S. Sengupta ◽

D. Martin ◽

A. Gelderloos ◽

...

Keyword(s):

Dynamic Modeling ◽

Flow Characterization ◽

Wet Weather ◽

Wet Weather Flow ◽

Treatment Designs

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City of Toronto's Wet Weather Flow Management Master Plan

Impacts of Global Climate Change ◽

10.1061/40792(173)167 ◽

2005 ◽

Author(s):

M. D'Andrea ◽

W. J. Snodgrass ◽

P. D. Chessie

Keyword(s):

Master Plan ◽

Flow Management ◽

Wet Weather ◽

Wet Weather Flow

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Water, Water Everywhere! - Overview of Sustainable Collection System Strategies for Effective Wet Weather Flow Management

Proceedings of the Water Environment Federation ◽

10.2175/193864712811704053 ◽

2012 ◽

Vol 2012 (7) ◽

pp. 7443-7451

Author(s):

D. Ott ◽

P. J. Bradley ◽

J. Gellner ◽

C. W. Tabor ◽

J. Sandino ◽

...

Keyword(s):

Collection System ◽

Flow Management ◽

Wet Weather ◽

Wet Weather Flow

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Bench to Full-Scale Enhanced Primary Treatment of Municipal Wastewater under Wet Weather Flow for Minimized Pollution Load: Evaluation of Chemical Addition and Process Control Indicators

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0515 ◽

2020 ◽

Author(s):

Mirna Alameddine ◽

Abdul Rahim Al Umairi ◽

Mohammed Zakee Shaikh ◽

Mohamed Gamal El-Din

Keyword(s):

Process Control ◽

Municipal Wastewater ◽

Weather Conditions ◽

Primary Treatment ◽

Full Scale ◽

Operation Conditions ◽

Wet Weather ◽

Slow Mixing ◽

Load Evaluation ◽

Online Process

The enhanced primary treatment of municipal primary influent under wet weather conditions was studied through a comprehensive approach from bench to full scale. The study delivered a practical solution for managing seasonal fluctuations in the influent wastewater by determining the most effective operation conditions for coagulation/flocculation. Three metal-based coagulants were tested through a series of jar tests. Alum outperformed other coagulants since 1 mg of Al added as alum with low mixing was able to remove 22 NTUs, 19 mg COD and 0.8 mg ortho-P. Three-factor ANOVA indicated that TSS removal depended mostly on rapid mixing while COD and ortho-P removals depended on slow mixing and coagulant dose. In bench and full-scale operations, the addition of polymer did not lead to any pronounced improvements. Finally, turbidity and percent ultraviolet transmittance showed good correlation with TSS and ortho-P which evokes their use as surrogates for micropollutants removal and online process control.

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The Erosion and Movement of Sediments and Associated Pollutants in Combined Sewers

Water Science & Technology ◽

10.2166/wst.1992.0184 ◽

1992 ◽

Vol 25 (8) ◽

pp. 101-114 ◽

Cited By ~ 31

Author(s):

R. M. Ashley ◽

D. J. J. Wotherspoon ◽

B. P. Coghlan ◽

I. McGregor

Keyword(s):

Field Data ◽

Bed Load ◽

Surficial Sediments ◽

Sediment Erosion ◽

Weak Layer ◽

Sewer Systems ◽

Combined Sewer ◽

Wet Weather ◽

Wet Weather Flow

The complex and inhomogeneous nature of sediments in sewers, and the variability of the particles and dissolved substances flowing in dry and wet weather combined sewage, make the prediction of sediment erosion and pollutant release a difficult proposition. It is apparent that the erosion of sediments in sewers can release pollutants in concentrations which exceed by many times the levels found in the various contributing sources of the sediments and pollutants, and whilst this release is normally in the form of an initial highly polluting foul flush at the start of wet weather flow, the occurrence of foul flushes has not been found to be ubiquitous, even from event to event in the same sewer. The origins of foul flushes may be attributable to the speedy erosion of a weak layer of highly concentrated surficial sediments (or bed-load) at the start of wet weather flows. Various models have been proposed, and some successfully applied to field data, to simulate the erosion and movement of sediments and associated pollutants in combined sewer systems.

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