Intensified BOD Removal, Nitrification & Denitrification

Your challenge:

Intensify your BOD, ammonia, or nitrate removal

Meet ammonia, BOD, and/or nitrate limits: You need a solution that can consistently hit required Total Ammonia-Nitrogen, cBOD₅ and Total Nitrogen/Nitrate removal levels.

Increase the surface area available to attached-growth microorganisms: By growing nitrifying and heterotrophic biomass on a surface, BioPorts minimizes the washout associated with suspended-growth systems.

Intensification maximizes treatment: In situations where your loading is high strength or highly variable, you need a system that can respond most dynamically.

Our technology:

Nexom is the exclusive source for the BioPorts™ moving bed biofilm reactor (MBBR) or Integrated Fixed-film Activated Sludge (IFAS). BioPorts combines concentrated attached-growth reaction kinetics with Nexom’s unmatched biological treatment expertise to create an industry leading nitrification, denitrification, and BOD removal technology.

Our BioPorts case studies

Maricopa, Arizona

Project Background & Challenges In 2019, the Global Water - Palo Verde Water Reclamation Facility (WRF), located in northeastern Maricopa, AZ, was serving a growing population of 48,629...

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Absarokee, MT

Project Background & Challenges In 2016, the CDP of Absarokee in Stillwater County, MT began looking for solutions to upgrade their existing three cell aerated lagoon. As their serviced...

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Palmyra, WI

 Project Background & Challenges Since the late 1970s, the Village of Palmyra, WI Wisconsin was operating a three-stage aerated lagoon. Faced with requirements for additional capacity and more...

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Seneca Landfill, PA

Project Background & Challenges Officially opened in 1965 just 25 miles north of Pittsburgh, the wastewater treatment plant at Seneca Landfill has the capacity to store millions of gallons of...

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Leeds, AL: BioPorts MBBR

Project Background & Challenges In the heart of Alabama, where the counties of Shelby, Jefferson, and St. Clair intersect, sits the town of Leeds, birthplace of basketball legend Charles...

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Key Advantages:
  • Wastewater treatment intensification offers more treatment capacity in a small footprint
  • Handles variable loading
  • Media size optimized for huge surface area while allowing for more coarse screening
  • Operational simplicity
  • Nitrification
  • Pre- or post-denitrification
  • BOD reduction
  • Activated sludge plant upgrades (as part of BioPorts iFAS)
  • New IFAS installations (Integrated Fixed-film Activated Sludge)
  • Small-footprint lagoon pre-treatment or polishing

How it works

How it works

Reliable, simple, intense.

BioPorts MBBRs work based on a series of basic principles, offering them three key advantages:

BioPorts MBBRs are reliable.

When flows increase quickly, it can overwhelm an activated sludge system’s capacity and cause biological washout.

With BioPorts, your biology is fixed where you need it: in your treatment basin, fixed to the surface of BioPorts media which themselves are retained using coarse screens. No more biology washout.

BioPorts MBBRs are simple.

Balancing return activated sludge is a challenging part of managing an activated sludge plant, and although the improvements in oxygen transfer make it well worth it, managing membrane-based or, more challenging yet, fixed-pore fine-bubble aeration adds to an operator’s workload.

With BioPorts MBBR, you don’t need to return your activated sludge because, again, your active biology is fixed directly to the media retained in the basin using coarse screens. And because moving media both impedes the rise and breaks up the aeration bubbles, lower-maintenance membrane-free diffusers can be used while achieving the same oxygen transfer.

BioPorts MBBRs are intense.

When your facility was first designed, it probably wasn’t being asked to handle the high strength or variability as you’re seeing now, and that was when it was brand new!

Create and retain the density of treatment to better handle today (and tomorrows’s) loading levels and their fluctuations, all thanks to your BioPorts MBBR.

BIOPORTS Components

BioPorts Media: 600-14

Media Design
Biofilm coverage
US Metric
Outer diameter 0.70 in 18 mm
Cylinder length 0.55 in 14 mm
Biologically-active surface area 179 ft²/ft³ 589 m²/m³
Material High-density polyethylene (HDPE) with carbon black added for UV protection
Specific gravity 0.96
Max aerobic fill capacity 67%
Max anoxic/anaerobic fill capacity 50%

BioPorts Media: 900-09

Media Design
Biofilm coverage
US Metric
Outer diameter 0.67-0.78 in 17-20 mm
Cylinder length 0.35 in 9 mm
Biologically-active surface area 287 ft²/ft³ 942 m²/m³
Material High-density polyethylene (HDPE) with carbon black added for UV protection
Specific gravity 0.96
Maximum aerobic fill capacity 67%
Maximum anoxic/anaerobic fill capacity 50%

Media Screens

BioPorts media retention screens are fine enough to keep the biofilm-carrying media from escaping the basin, but coarse enough to allow particulates to pass through and prevent the screen from fouling or blinding.

Media screens can also be arranged in parallel to better accommodate variable flows. Vertical screens with above-surface access ports can be used to enable better access for effluent sampling or occasional screen maintenance.

Fixed Grid Aeration

Through the collaboration with EDI, a fellow Axius Water company, even our products are “Stronger Together,” and our aeration capabilities are the envy of the industry. Most BioPorts facilities are designed with EDI fixed grid aeration within our basins to optimize performance with minimal O&M.

In fact, based on that aeration expertise, Leeds, Alabama’s BioPorts MBBR is able to achieve optimized mixing and oxygen-transfer with ~25% of the energy typically required.

What it Delivers


The BioPorts™ process is the best choice for roughing high influent BOD, polishing ammonia, or upgrading to IFAS. In place at dozens of installations across North America, BioPorts MBBRs or IFAS installations deliver as promised and ensure that operators sleep well at night knowing they have the system in place to beat their BOD and nutrient limits.

Want to know what BioPorts could do for your system?

Submit your RFP today and our on-staff professional engineers can help you size and design a BioPorts MBBR to meet your wastewater treatment requirements.



There are many factors which can influence the cost of a BioPorts system, including design flows, loading, treatment requirements, and existing infrastructure. The best way to determine the cost for your specific application is to submit your RFP to our project development team.


Based on its small footprint design and modular scalability, BioPorts is among the most simple wastewater treatment solutions to upgrade, whether your focus is further nitrification or BOD removal, denitrification to meet Total Nitrogen limits, or beyond.


Almost never. The media is sized so that it can be retained by coarse effluent screens for no downstream media loss, and it is built from durable HDPE that means the BioPorts media that you start with should last the life of your installation.


If you are looking to achieve <1 mg/L of ammonia in freezing cold water, Nexom has already solved that problem with the SAGR, which has numerous proprietary advances that help it overcome limitations related to cold lagoon effluent.

BioPorts is tremendously effective in many post-lagoon settings, so to identify which solution is best for you, reach out and let our Nexom engineers guide you.