Ballasted Clarifiers

BioMag and CoMag® Systems from Evoqua are next generation wastewater and water solutions that increase the capacity and contaminant removal capabilities of primary, secondary, and tertiary treatment systems.

Maximum capacity, performance & control; minimum footprint & capital

The technologies make the fundamental process of clarification far faster, far more reliable, and far more compact than alternate technologies. They give the operator far more control over effluent values, and a far more robust plant.

Simple, Reliable, Robust
This ground-breaking technology infuses magnetite as a weighting agent into chemical or biological floc, resulting in rapid and enhanced settling and clarification.  The technology can be cost effectively applied to both new or existing treatment plants, and greatly reduces footprint and tankage. The process creates much more concentrated suspended solids, and a more dense and stable sludge blanket that makes plants less prone to load and flow variations, and delivers superior nutrient and solids removal.  Magnetite is efficiently recovered and recycled.

The BioMag Ballasted Biological Treatment System enables an existing plant to double or triple its biological treatment capacity and achieve Enhanced Nutrient Removal limits all within existing tanks.  BioMag routinely delivers:
  • TN < 3.0 mg/L
  • TP < 0.2 mg/L
  • Turbidity < 1 NTU  

The CoMag® Particulate Removal System can produce effluent nearly equivalent to ultra-filtration at capital and operating costs competitive with conventional alternatives.  It is a perfect technology for tertiary treatment and CSO and storm water management.  CoMag routinely delivers:
  • TP < 0.05 mg/L
  • TSS < 2.0 mg/L
  • Turbidity < 1 NTU

BioMag and CoMag Systems are gaining rapid acceptance by municipalities and engineers.
  - BioMag Systems:  3 operating plants; 12 more in design
  - CoMag Systems:  8 operating plants; 6 more in design

Read here - A study recently presented at WEFTEC 2013 demonstrates that magnetite utilized in the BioMag™ System has no negative impact on oxygen transfer efficiency in a fine bubble aeration system

A Perfect Fit with Evoqua
Evoqua purchased the technologies through the acquisition of Cambridge Water Technologies in early 2012.  Cambridge Water, a leader in high rate water and wastewater treatment, pioneered the commercial application of ballasted floculation in biological systems. These treatment breakthroughs are now backed by the applications experience, technical expertise, and complimentary technology portfolio of Evoqua.
Now More than Ever 
The increase in treatment requirements, the aging of existing plants, the need for more capacity, and the strain on municipal budgets, all mean that now more than ever is the time for this technology and its promise of breakthrough, cost effective performance.

Ballasted Clarifiers Case Study

Sturbridge, Massachusetts POTW: Greater Capacity for High Flow Events, With Enhanced Clarification for New Regulations

Sturbridge, Massachusetts historically suffered from periodic blooms of filamentous bacteria that caused bulking in the secondary clarifiers of their three activated sludge package plants. The elevated clarifier solids loading rates (SLR) during high flow events often caused excessive sand filter backwash cycle times and occasional diversion of excess flow to a neighboring publicly owned treatment works (POTW).  Sturbridge’s need for additional treatment capacity in a highly constricted footprint, coupled with tighter permit limits for BOD, TSS, total nitrogen (TN) and phosphorus (TP), created the need to upgrade the wastewater treatment plant.

Read Full Case Study

Ballasted Clarifiers

BioMag System for Enhanced Secondary Treatment
CoMag System for Enhanced Primary or Tertiary Treatment

Here is a quick view of Magnetite Ballasted Treatment in action!

Articles and Technical Papers

It's All Settled: A Phosphorus Reduction Process Using Magnetite Ballast Helps Massachusetts Treatment Plant Consistently Meet Strict Effluent Limits (Reprinted with permission from TPO Magazine, December 2014)
Magnetite Addition is Part of a Clarification System that Helps a New Hampshire Plant Deal with Wet-Weather Flows (Reprinted with permission from TPO, March 2014)
The Impact of Magnetite Ballast on Oxygen Transfer and Alpha
Maximizing Nutrient Removal in an Existing SBR With a Full-Scale BioMag Demonstration
BioMag Treatment of High Wet Weather Flows
Beyond Desktop Evaluation: Key Design Criteria for Mixing and Settling of Magnetite-Impregnated Mixed Liquor (Abstract)
Beyond Desktop Evaluation: Key Design Criteria for Mixing and Settling of Magnetite-Impregnated Mixed Liquor (Full Paper)

News Release
ACEC Awards Tighe & Bond for Plant Upgrade With Innovative BioMag and CoMag Water Treatment Systems

Case Studies
Sturbridge POTW - Greater Capacity for High Flow Events, With Enhanced Clarification for New Regulations
Town of Concord WWTP - Enhanced Clarification Results in Dramatic Phosphorus Reduction
Long Trail Brewing Company - Higher Water Treatment Capacity With a Minimal Footprint

Frequently Asked Questions

General Questions About Magnetite
Questions About BioMag Systems and the Use of Magnetite in Biological Processes
Questions Related to CoMag Systems
Download a pdf of all FAQs

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