A Closer Look at MBR Technology
Exploring the technology behind the plant upgrade
Wastewater treatment is an essential service that protects public health, preserves our local waterways, and supports the long-term health of our community. As wastewater treatment technology continues to advance, communities have new opportunities to improve treatment performance while making better use of available space and resources.
One technology gaining attention in municipal wastewater treatment is the Membrane Bioreactor, or MBR. As we explore options for a potential plant upgrade, let's take a closer look at what MBR technology is, how it works, and why it may be a promising option for our facility.
What is an MBR?
MBR stands for Membrane Bioreactor. It combines two important wastewater treatment processes: biological treatment and membrane filtration.
During biological treatment, naturally occurring microorganisms break down organic waste in wastewater. The membrane system then acts as an extremely fine physical barrier, separating treated water from suspended solids and much of the remaining biological material.
Traditional treatment systems commonly use settling tanks, called clarifiers, to separate solids from treated water. An MBR system uses membranes for this separation instead, which can reduce the space required for treatment while producing very clear, high-quality effluent. This is especially important as Waterville Valley has one of the strictest discharging permits in the U.S.
How Does MBR Technology Work?
A Membrane Bioreactor (MBR) combines the natural cleaning power of microorganisms with advanced membrane filtration to treat wastewater. The process can be broken down into three main steps:
1. Biological Treatment:
Wastewater enters a treatment tank where naturally occurring microorganisms break down organic waste and other biodegradable particles. These microorganisms play a vital role in cleaning the water before it moves through the membrane filtration process.
2. Membrane Filtration:
Next, the water passes through specialized membranes containing microscopic pores. In the ZeeWeed MBR system, these membranes act as a physical barrier, retaining suspended solids, bacteria, and much of the biological material while allowing treated water to pass through. This produces high-quality effluent with very low suspended-solids concentrations.
3. Treated Water:
The resulting treated water, known as effluent, can then move on to any required final treatment or disinfection before being discharged in accordance with the facility's permit requirements. In Waterville Valley’s case, the effluent would go through UV disinfection banks before being discharged into the Mad River.
In short, MBR technology combines biology and advanced filtration to help turn wastewater into treated water that meets established environmental standards.
Evaluating MBR Technology for Our Plant
We are currently working with a team of engineers from Black & Veatch to evaluate two different types of Membrane Bioreactor (MBR) systems. One of the technologies under consideration is a hollow-fiber membrane system, which is currently our leading option. By comparing the available technologies, we can better understand their treatment capabilities, maintenance requirements, operating costs, and long-term reliability before determining the best fit for our facility.
Our research has been hands on as well. I recently visited the wastewater facility on top of Mount Washington here in New Hampshire to meet with the site's lead wastewater operator and representatives from the New Hampshire Department of Environmental Services (NHDES). During the visit, I gained hands on experience with a ZeeWeed MBR working with the lead operators and NHDES to take down an MBR train.
Experiences like this are valuable because selecting a treatment system is only part of the equation. Understanding how the equipment performs in the field, how it is maintained, and what operators need to keep it running reliably is just as important.
Our goal is to make an informed decision that balances treatment performance, operational demands, long-term costs, and environmental protection. By working with experienced engineers, learning from facilities already using MBR technology, and carefully evaluating our options, we are taking a thoughtful approach to planning for the future of wastewater treatment in our community.
Good infrastructure starts with good planning. We believe that investing the time to understand these technologies today will help us make a better decision for our facility and the community we serve for years to come.