Freeze-thaw cycles: bad for roads, but really good for dewatering.

DATE POSTED: April 9, 2019


How does a Bishop Solids Management Solution fare in the wintertime?

For most municipalities, springtime freeze-thaw cycles are a problem, causing damage to roads, bridges and other infrastructure. But for the Bishop Solids Management Solution, with Geotube® containers, freezing and thawing is a natural wonder that provides a tremendous boost to the dewatering process and can help reduce the volume of a container by as much as 50%.

geotube, freeze-thaw

This happens because water expands when it freezes, so the ice crystals that form inside the Geotube® container cause compression of the solids and force more water to be squeezed out. Once the Geotube® container thaws, the water is released and the solids are further consolidated. The best part is that the freeze/thaw/consolidation process happens naturally, costs nothing, and requires no oversight from plant operators.

It’s not unusual to see the volume of a Geotube® container shrink by as much as 50%. This volume reduction frees up space in the bag, and enables it to be refilled with solids— though we recommend that you wait until the Geotube® container is fully thawed before pumping into it again. A full thaw can take several weeks due to the size of the container, but as a general rule, once the ground is free of frost your Geotube® container is ready to accept more solids.

Once the Geotube® container is full again–and if you have space–let it sit over winter and freeze again. In some cases, the dewatering and consolidation may be sufficient to allow you to refill the container again. Some of the sites we service have been using the same Geotube® container for three or four seasons. But even if the container can’t accept more solids, the additional dewatering and volume reduction will help reduce the time and cost of hauling the solids off-site.

Learn more about the Bishop Solids Management Solution for containment and dewatering of solids.

Contact us with your questions about the Geotube® freeze/thaw/consolidation cycle and to arrange a dewatering test of your solids.

 

 

How to redesign septage lagoons to accept more loading in less space

DATE POSTED:


It’s getting harder to find nearby wastewater lagoons that accept septage. Whether a site has limited capacity or is unable to handle high-strength septage, it means many haulers are unable to empty their trucks locally, forcing them to travel farther to reach lagoons that can accept them.

lagoons, geotube, septage, loading

 

A simple, easy-lagoons, geotube, septage, loading to-operate upgrade to wastewater lagoons could enable virtually any site to accept significantly more septage without expanding the lagoon footprint, operate more efficiently and potentially increase revenue from septage disposal.
The Bishop Solids Management Solution enables septage lagoons to make a simple process modification that enables it to accept high-strength waste and more solids without process upset or compromising capacity.
To achieve these benefits, the Bishop Solids Management Solution, with Geotube® containers becomes the septage receiving point instead of the lagoon. Septage is pumped directly from the truck, or from a holding tank, to a Geotube®lagoon, loading, reduced footprint container, which provides both containment and dewatering of the septage.

 

lagoons, geotube, septage, loading As the septage is pumped into the container, it first passes through a 1/2-inch bar screen to separate unwanted solids such as trash and other debris. Then, a specially selected polymer is added, which enables the solids to begin dewatering and filtrate to flow through the container’s tiny pores almost immediately. This filtrate is collected by a non-permeable membrane and directed into the adjacent treatment lagoon.

To cope with the high levels of contaminants and nutrients that this filtrate may contain, Bishop Water can also retrofit a lagoon with its BioCord Reactors, a self-regulating, low-energy technology to achieve enhanced biological removal of nutrients and BOD. The modular reactors provide a high density, vertically oriented surface area—like a condominium for bacteria—that functions as an ideal medium on which to establish a stable, concentrated biofilm. This robust population of microorganisms is resistant to high hydraulic and organic loadings and dramatically improves the performance of the lagoon under normal and upset conditions.

 

Learn more about using Bishop Water’s solids management solution at a WTP.

Read our recent article in OOWA Onsite Magazine.

Contact us to discuss affordable process upgrades to your septage lagoon.

 

 

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A simple, affordable solution for high TSS washwater

DATE POSTED: February 1, 2019


Ontario growers prove Bishop Solids Handling System is ideal to reduce TSS in washwater

Washing vegetables can be a dirty job that produces a tough to treat waste stream of soil particles, vegetable debris and nutrients such as nitrogen and phosphorus. In many cases, farms must treat water to restore clarity and remove nutrients before discharge to a receiving body.

This is typically done using settling ponds, but for farmers in Ontario’s Holland Marsh, the soil is fine-textured and peat-like with low specific gravity that does not readily settle in conventional treatment ponds.

Bishop Water was invited by the Holland Marsh Growers’ Association (HMGA) to assist in developing a simple, affordable solution for washwater treatment after the group learned about the company’s success and experience in agricultural applications. Prior to this, the HMGA was experimenting with another type of non-woven fabric filter bags, but the bags were experiencing clogs, ruptures and poor solids retention — they were unable to reduce TSS to an acceptable level.

Water samples from the Bishop Solids Management Solution show wash water (left), one minute after the addition of coagulant (centre) and treated filtrate from the Geotube® container (right.)

Bishop Water installed a pilot system of its Solids Handling Solution. In this case, two 25-foot (7.6-metre) Geotube® containers were set up near the farm’s settling pond. Washwater was pumped at a rate of 350L (92.5 US gallons) per minute, treated with polymer to aggregate the small soil particles and then directed to the Geotube® containers.

Once inside, solids remained trapped, while clean filtrate trickled out through the tiny pores of the Geotube® container. The reduction in TSS averaged about 91%, with significant reductions in nitrogen and phosphorus also achieved.  A report of the pilot project, issued by the HMGA, stated that Geotube® dewatering is a viable option to treat vegetable was and flume water.

A Geotube® solution provides a much more reliable method to capture the organic muck and achieve major reductions in solids and nutrients that are entering receiving bodies. Once full, a Geotube® container can be cut open and the soil inside can be reclaimed for continued agricultural use.

Learn more about using Bishop Water’s solids management solution at a WTP.

Contact us to discuss dewatering options for your WTP.

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Reduce labour requirements for dewatering with Bishop Water’s solids management solution

DATE POSTED: November 23, 2018


Growing community uses Bishop Water’s low-maintenance solids management solution to reduce labour requirements

A simple, low-energy solids management solution was able to significantly reduce labour requirements for sludge dewatering at the Meteghan Sewer Treatment Plant (STP) in the Municipality of Clare, Nova Scotia.

“We used to have sand drying beds to dewater sludge at the Meteghan STP,” says Jody Comeau, Treatment Plant Operator at the Meteghan STP. “It took us three weeks on average to dewater a full tank of sludge because this approach was very labour-intensive. After replacing the sand drying beds with Bishop Water’s solution, we can now dewater the same volume of sludge in only five hours.”

Since November 2016, the Meteghan STP has dewatered about 1,000,000 litres of sludge. The plant has saved hundreds of hours in labour costs using Bishop Water’s low-maintenance solids management solution. The easily installed Geotube® containers are each rolled out in a laydown area measuring 57-feet long and 45-feet in circumference. Each container is pumped to a maximum of seven feet (two metres) in height. Then, the units draw down as the unit dewaters.

reduce labour requirements

“Bishop Water’s solids management solution was installed in the same location where we had the sand drying beds before,” Comeau says. “This worked out well for us because we didn’t have to do much to accommodate the system. We’re also really happy with the support we’ve received from Bishop Water’s team. It’s only a phone call away if we ever have any questions.”

Bishop Water’s highly experienced team provides comprehensive services to design, install and service a multitude of Geotube® dewatering solutions. They provide clients with specialized technicians trained to operate, troubleshoot, and service its solids management solutions.

Learn more about using Bishop Water’s solids management solution at a WTP.

Contact us to discuss dewatering options for your WTP.

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