Is your lagoon suffering from washout?
DATE POSTED: February 28, 2023
Every wastewater plant can experience washout—a condition where high hydraulic loading causes microorganisms to be flushed out of a treatment cell at a faster rate than they can be replenished. It happens during periods of peak sanitary flow or during wet weather and its occurrence may be on the rise as we experience more frequent and extreme precipitation due to climate change. Inflow and infiltration can compound the problem adding more water to the sanitary system and further diluting the treatment process.
Diagnosing washout at your plant
Reducing retention times in treatment cells is the most common approach to enable lagoons to accommodate high hydraulic loading and avoid the need to bypass one or all of the treatment steps. But due to the faster flow, operators may see a decline in the treated effluent quality.
The telling sign of washout is that even after the influent flow returns to normal levels, the quality of treated effluent may continue to suffer days or even weeks after the event. This lag in performance indicates that a significant portion of the microbiological population has been lost to washout and the remainder is unable to provide adequate nutrient removal. The condition will continue until the microbiological population is re-established to the optimum level.
In the warmer months, the microbial population can rebound fairly quickly. But since temperature plays a major role in the growth rate of nitrifying and heterotrophic bacteria, a washout in the fall or winter can have serious long-term consequences to lagoon performance. If temperatures drop after a washout event, the microbial population may not fully recover until the spring, which means the plant could have to operate at reduced capacity or face compliance issues through the cold-weather period.
Build a better home for bacteria
BioCord™ Reactors are a simple, low-energy, fixed-film treatment technology that can help prevent the washout problem. BioCord is like a condominium for bacteria that adds a massive amount of surface area to a lagoon cell and provides the ideal environment for preferred, naturally occurring bacteria to thrive. Even though suspended bacteria may be lost to washout, BioCord retains its productive biofilm. The biofilm continues providing treatment, while also helping the lagoon return to optimum performance following the high-flow event.
BioCord boosts cold-weather performance too
The BioCord Reactor system is also designed to provide reliable removal of ammonia and BOD in cold weather. One way BioCord does that is by increasing the inventory of bacteria needed for wastewater treatment far beyond the capabilities of ordinary suspended sludge systems. More bacteria, means more nitrification and BOD removal.
Another way is that the BioCord biofilm develops in layers, which helps insulate inner microorganisms from cold water. This enables nitrifiers to maintain ammonia removal and respond to loading rates even when the wastewater temperature is as low as 0.5°C. BioCord biofilm has repeatedly demonstrated its ability to tolerate and thrive in cold conditions with observable changes in biofilm growth and greater ammonia removal rates as loading increases.
Learn more about BioCord Reactors and watch our video to see how BioCord easily and affordably increases lagoon capacity and performance.
Contact us to discuss your concerns about washout and other wastewater treatment needs.
How to eliminate sewer surcharges with a simple, low-energy system
DATE POSTED: September 3, 2021
Pre-treatment of high-strength wastewater before discharging it to a municipal sewer can be challenging, especially if high levels of BOD, TSS and ammonia are present. But what if a simple, affordable, onsite solution was available to help meet pre-treatment requirements and avoid sewer surcharges?
Bishop Water combines two of its robust, easy-to-use treatment technologies—The Bishop Solids Management Solution and BioCord™ Reactors—to create a scalable solution for a wide range of industrial and commercial applications. The process can handle high solids and nutrient concentrations for a fraction of the capital and operating costs of more complex, energy-intensive alternatives.
How it works
The wastewater first goes to Bishop Water’s Solids Management Solution. Unlike complex, energy-intensive mechanical dewatering equipment, the Bishop approach utilizes a passive dewatering process that achieves a high level of dry solids using only specially selected polymers, Geotube® filtration and gravity.
As the solids are pumped to the Geotubes, a polymer is added to retain non-soluble BOD, TSS, and other contaminants. The Geotubes also provide filtration and release clear water that is low in TSS, but may still contains soluble organics and nutrients.
This nutrient-rich filtrate is then transferred to a BioCord Reactor system for further treatment. BioCord Reactors provide a simple, robust process to remove soluble BOD and ammonia with very little operator oversight.
A BioCord Reactor is simply a modular frame that supports densely arranged strands of polymer fibres. These fibres provide a massive surface area for the growth of aerobic and anaerobic microorganisms that are ideal for enhanced biological treatment and maintaining regulatory compliance – even in cold weather conditions.
This integrated solution can be customized meet the specific size constraints, treatment requirements, and growth plans for each site. The system also incorporates a modular design that can be easily expanded as treatment needs change.
Learn more about Bishop Water’s solids management and nutrient removal solutions.
Contact us to discuss treatment options for your facility.
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Quality and quantity: How a BioCord frame delivers strength and value
DATE POSTED: April 29, 2021
When it’s dry, a metre of BioCord weighs almost nothing. But after it’s immersed into a wastewater system and becomes a home for a healthy, active biofilm, it really packs on bulk. Each metre of once-wispy BioCord can weigh as much as four kilograms when it’s fully populated with aerobic and anaerobic microorganisms.
A reactor frame can be fitted with more than 600 metres of BioCord, so it’s easy to see that the supporting frame must be strong to handle the dramatic increase in mass as the biofilm develops.
The Bishop Water team has tested a number of designs and materials to create the optimum BioCord frame that offers the greatest strength, reliability and service life at the lowest cost. For most applications, aluminum offers a strong, but lightweight, frame that can be customized to any size and will support the full weight of the BioCord media along with the active biofilm layer. Overall, the design of our aluminum frames offers the performance of stainless steel, but at about half the weight and half the cost.
All BioCord frames are manufactured in Canada to ensure that we can maintain tight control on quality and delivery times. It also enables us to respond quickly to orders and reduces shipping time and cost.
Our frames are assembled in a modular fashion during the manufacturing process and then prepared for shipping in a flat pack. This arrangement greatly reduces the space required for shipping and the cost. Once the frames arrive at their destination, they can be quickly assembled and then brought to site ready to install. In many cases, a BioCord system can be fully installed in just a few days, while the plant remains in operation.
Learn more about the advantages of BioCord reactors for wastewater treatment.
Contact us to discuss a BioCord pilot system for your facility.
It’s curtains for BioCord!
DATE POSTED: March 29, 2021
BioCord curtain design enables fast, easy retrofit to enhance CAS basins.
We often refer to BioCord as a condominium for bacteria, suspended in a free-standing aluminum frame that facilitates fast, easy installation into treatment lagoons.
But that’s not the only way that we can configure this versatile nutrient removal system. Another option is the curtain design that enables BioCord to be installed in concrete or steel process tanks to enhance a conventional activated sludge process. These curtains are fixed within the treatment basin, eliminating concerns of carrier washout or clogging that sometimes arise with similar MBBR systems.
In this configuration, we suspend the BioCord media from stainless steel cables that span the width of a process tank. Our process specialists calculate the appropriate amount of BioCord that should be added to the process tank to achieve the target removal rates for ammonia, total nitrogen and BOD.
Once installed, the BioCord media provides a massive surface area on which nutrient-removing bacteria can attach and form a highly efficient and highly concentrated biofilm. The BioCord media is made up of a blend of durable, inert materials, meaning that no replacement of the fibres are required as long as they are not physically damaged. This approach can significantly increase plant performance and capacity within the existing footprint, eliminating the cost of additional process tanks and related equipment.
BioCord curtain systems also require little energy to operate. Unlike similar technologies that use individual carriers to support biofilm growth, BioCord Curtains are fixed in place, and do not require additional energy to keep the media circulating and/or in suspension.
In some cases, the existing aeration system may provide sufficient oxygen to maintain BioCord and the existing activated sludge process. This may If not, the BioCord compressor-powered aeration system can achieve high oxygen transfer to the biofilm for a fraction of the capital and operating cost of typical blower-powered systems.
Learn more about Bishop BioCord Reactors for treatment plant upgrades.
Contact us to discuss your wastewater treatment needs.
Bishop Water’s global growth featured in Ottawa Business Journal
DATE POSTED: January 27, 2021
There’s a growing global need for simple, low-energy solids management and nutrient removal solutions. The Ottawa Business Journal recently interviewed Bishop Water CEO Kevin Bossy to learn how BioCord Reactors and the broader solutions portfolio provide the right mix of simplicity, affordability and performance to expand quickly into international markets.
Read the full article in the Winter issue of the Ottawa Busines Journal; Ottawa’s tech firms to watch.
Learn more about our simple, low-energy solutions for nutrient removal and solids management.
Ammonia discharge limits are tightening up for Canadian mines. Be ready with a BioCord system
DATE POSTED:
By June 1, 2021 metal and diamond mines in Canada will need to comply with a new lower discharge limit for unionized ammonia. Over 100 mines will be affected by this revision to the Metal and Diamond Mining Effluent Regulations (MDMER), which sets a federal effluent limit of 0.5 mg NH3/L.
To achieve this new regulation, changes may be needed to a mine site’s wastewater treatment system. But the new ammonia target can likely be reached without the need for complex or costly technology upgrades. Many mine sites use simple lagoon systems for wastewater treatment—in part due to their ease of use and low operating costs—and there are upgrade options that can maintain this simplicity and affordability while also improving ammonia removal.
More nitrifying bacteria = better total ammonia removal
A simple, fixed-film biological treatment system such as Bishop BioCord™ Reactors can dramatically improve total ammonia removal, without significant changes to the way a lagoon is operated. That’s because a BioCord system is designed to enhance the existing lagoon process rather than add another step or sidestream process to the plant.
Unlike moving-bed or submerged-bed biofilm systems, which require additional tanks or cells, BioCord Reactors can be installed directly into the treatment lagoon to provide a massive surface area on which preferred, naturally occurring bacteria can grow. It’s like a condominium for bacteria; made from densely arranged loops of polymer fibers that are suspended from free-standing frames. This enables BioCord to establish a robust population of nitrifying bacteria that is many times greater than what can be maintained in an ordinary activated sludge lagoon.
BioCord isn’t limited to upgrades only. This modular system can also form the foundation for new wastewater treatment plants that are designed as lagoons, tanks or even temporary containers.
High oxygen transfer is critical
Each frame is also equipped with a micro-bubble aeration system powered by a low-energy compressor. This design enables the system to achieve high oxygen transfer to the biofilm for a fraction of the capital and operating costs of a typical blower-powered lagoon aeration system. Oxygen is a critical, and often limiting, parameter for nitrifying bacteria to proliferate, so having high oxygen transfer at a low energy cost is a tremendous advantage.
Once operational, a BioCord system acclimatizes and adapts to the range of pH, temperature and contaminants that it may experience in the mine’s wastewater lagoon, including high levels of ammonia, nitrogen and cyanide.
BioCord testing shows that the system can achieve over 99% ammonia reduction in synthetic wastewater concentrations as high as 750 mg/L. Since the system is modular, the system can be sized to meet the required ammonia target and quickly expanded if conditions change.
Learn more about the Metal and Diamond Mining Effluent Regulations.
Learn more about BioCord Reactors for high strength wastewater treatment.
Contact us to discuss your high strength wastewater treatment needs.
Top 5 things to consider for a lagoon upgrade
DATE POSTED: December 22, 2020
Wastewater lagoons provide simple, reliable and relatively low-cost treatment for small and medium sized communities. In Canada and the US, there are nearly 10,000 municipal lagoon systems and many more when industrial, agricultural and commercial lagoon systems are included.
But eventually a community needs to improve the treatment capacity and performance of its lagoon system to accommodate growth, meet more stringent regulatory requirements, or both. We’ve compiled a list of important considerations to help you plan a lagoon upgrade that can provide the performance and capacity your community needs at affordable capital and operating costs.
1) Post-lagoon or in-situ treatment process
Moving-bed and submerged-bed systems typically add tanks or in-ground cells to accommodate the new treatment process. Not only does this add to the plant footprint, it also requires additional equipment such as tanks, pipes, pumps and blowers, which can substantially increase capital costs. In-situ systems can be installed directly into the lagoon to enhance treatment capacity without expanding footprint or adding a large amount of supporting equipment.
2) Energy demand
Blowers can provide lots of air quickly, but the equipment is costly and has high energy demands. Some systems such as MBBR also rely on coarse bubbles from blowers to circulate the carrier media and keep it in suspension, in addition to supplying air to the microbial population. But larger bubbles are also less efficient at transferring oxygen to microbes – much of the air simply bubbles up and out of the process tank. Instead, consider a system that uses low-energy compressors and micro-bubble aeration for significantly higher oxygen transfer and lower, more efficient energy usage.
3) Ease of operation
One of the big advantages of wastewater lagoons is that they require little operator attention compared to more advanced mechanical treatment plants. In-situ systems can also share this advantage since they align well with the way wastewater lagoons are typically managed and don’t add complexity or additional processes to manage.
4) Capital and long-term operating costs
Tanks, media beds, blowers and other equipment can all add capital and operating costs to a lagoon upgrade. Alternatively, in-situ systems use the existing lagoon cell, which can reduce capital costs by as much as 50%. Energy demand for in-situ systems can also be up to 50% lower by eliminating the need to pump wastewater to sidestream process and replacing blowers with low-energy compressors.
5) Customizability
Like any wastewater system, lagoons can experience variable loading, changing flows, upset and more. Upgrade technologies should be easily adaptable to respond to short- and long-term operating conditions, including anticipated changes to population and regulatory requirements. To achieve this, consider modular systems that can be brought online as needed or easily expanded to accommodate the needs of the community or business.
BioCord Reactors check all the boxes
BioCord™ Reactors biological nutrient removal gives lagoon operators a simple and efficient way to dramatically increase capacity and performance of a wastewater lagoon or conventional activated sludge plant without expanding footprint. This low-energy, self-regulating process is ideal to help a plant achieve up to 99% ammonia reduction in difficult treatment conditions such as during cold weather or when experiencing high-strength or variable loading. The fixed-film, modular process is like a condominium for bacteria on which preferred, naturally occurring bacteria can thrive. BioCord reactors offer a flexible, modular design that can be customized to fit virtually any secondary treatment process and handle anticipated flow and loading parameters.
Learn more about BioCord Reactors for lagoon upgrades.
Contact us to discuss your wastewater treatment plant upgrade.
Learn how BioCord and baffle curtains are enhancing performance at Limoges WWTF
DATE POSTED: October 6, 2020
Baffle curtains now surround two cells of BioCord™ Reactors that were installed as part of an upgrade for the Limoges WWTF in The Nation Municipality. The baffle curtains are an important component to maximize contact between the raw wastewater in the lagoon cells and the BioCord biofilm that breaks down the ammonia.
The baffle curtains achieve this by forming a raceway that directs the flow of wastewater through a series of 180 degree turns. This arrangement not only provides the most intensive arrangement for the 30 BioCord Reactors that make up each cell, but also a compact footprint. The two cells will operate in parallel with the incoming flow spilt between them. Each cell is designed to reduce influent ammonia from 30 mg/L to 1 mg/L in the summer and 5 mg/L in the winter.
Treatment lagoons typically struggle to achieve ammonia removal in the winter months, when cold temperatures reduce the population and activity of nitrifying bacteria. The BioCord system, along with other upgrades to the facility, will enable the Limoges WWTF to improve cold-weather performance and alter its operation from intermittent to continuous discharge. These process changes will also provide a dramatic increase to its treatment capacity, increasing it from 1,500 m3/day to 3,500 m3/day.
As a result of this $10 million project, which also includes screening, grit removal, disk filtration and UV disinfection the Nation Municipality can extend the life of its wastewater lagoon system and avoid the need to replace it with a costly mechanical treatment plant.
BioCord Reactors are a made-in-Canada solution that is tested and proven to provide low-energy, self-regulating nutrient removal throughout the wide range of seasonal operating conditions that a plant experiences. The easy-to-operate system aligns well with the way wastewater lagoons are typically managed. With an optimized BioCord system, wastewater lagoons can accept greater nutrient loading, decrease retention times and improve effluent quality—especially in cold-weather conditions.
Watch our webinar series or visit our website to learn more about Bishop BioCord Reactors for enhancing cold weather performance in municipal and industrial wastewater lagoons and conventional activated sludge systems.
Contact us to discuss a BioCord system to achieve year-round enhanced ammonia removal in your wastewater lagoon or CAS plant.
Is your treatment plant suffering from washout?
DATE POSTED: August 28, 2020
Every wastewater plant can experience washout—a condition where high hydraulic loading causes microorganisms to be flushed out of a treatment cell at a faster rate than they can be replenished. It most often happens during periods of peak sanitary flow or during wet weather and its occurrence may be on the rise as we experience more frequent and severe storms due to climate change. Inflow and infiltration can compound the problem adding more water to the sanitary system and further diluting the treatment process.
Diagnosing washout at your plant
Reducing retention times in primary, secondary and tertiary processes is the most common approach to enable the plant to accommodate the higher hydraulic loading and avoid the need to bypass one or all of the treatment steps. But due to the faster flow, operators may see a decline in the treated effluent quality.
The telling sign of washout is that even after the influent flow returns to normal levels, the quality of treated effluent may continue to suffer for many hours or even days after the event. This lag in performance indicates that a significant portion of the microbiological population has been lost to washout and the remainder is unable to provide adequate nutrient removal. The condition will continue until the microbiological population is re-established to the optimum level.
Fall washout = winter performance problems
In the warmer months, the microbiological population can rebound fairly quickly. But since temperature plays a major role in the rate of microbiological growth, a washout in the fall or winter can have serious long-term consequences to plant performance, particularly for wastewater lagoons or other plants where secondary treatment occurs outdoors. In these plants, the microbial population may not fully recover until the spring, which means the plant could have to operate at reduced capacity or face compliance issues through the cold-weather period.
Build a better home for bacteria
Bishop BioCord™ Reactors are a fixed-film technology that can help alleviate the washout problem. BioCord is like a condominium for bacteria, enabling the formation of a robust biofilm with preferred microorganisms that are strongly attached to the growth media and resistant to washout. Even though suspended microorganisms may be lost to washout, microorganisms in the BioCord reactors remain in the system and continue to provide treatment while also helping re-establish suspended bacteria to optimum levels.
The BioCord Reactor system is also designed to provide robust cold-weather performance. BioCord biofilm develops in layers enabling both BOD- and ammonia-reducing bacteria to coexist and thrive. Layering also helps insulate inner microorganisms from cold water to remain active during the winter and continuing to provide nutrient removal.
Learn more about BioCord Reactors.
Contact us to discuss your concerns about washout and other wastewater treatment needs.
Did you miss our webinars?
DATE POSTED: July 30, 2020
Over the past few weeks our team ran a series of educational webinars that took a deep dive into Bishop BioCord Reactors and our new Rare Earth Advanced Coagulant for phosphorus removal.
Our five-part BioCord webinar series looked at every aspect of this simple, low-energy, fixed-film biological treatment process from the basics of how it achieves year-round ammonia removal, to pilot testing, full-scale design and process optimization. Whether you’re considering upgrades to an existing facility, or building a new one, watch our webinar series to learn how BioCord reactors provide low maintenance enhanced ammonia removal with capital and operating costs that are significantly lower than alternatives.
Shortly after that, we presented a webinar introducing a new, rare earth coagulant that outperforms alum- and ferric-based coagulants for phosphorus removal. We explained how this coagulant enables wastewater treatment plants to achieve ultra-low phosphorus levels — as low as 0.07 mg/L — without the need for costly tertiary filtration systems. It can also dramatically reduce sludge production; by as much as 50% in some cases, resulting in significant savings in sludge handling costs.
Visit our YouTube channel to watch the webinars and many more videos from Bishop Water.
Contact us to learn more about Bishop BioCord Reactors and the rare earth Advanced Coagulant.