Bubble Curtains for Water Intake Protections

Bubble Curtains with Bubble Tubing® Technology

Jellyfish blooms are a significant operational hazard for water intake structures. Large blooms can cause infrastructure damage, plant shutdowns and safety hazards if not mitigated properly. Technologies exist, such as trash racks, to filter jellyfish out of water intakes, but such measures are expensive and often just as labour-intensive to maintain. One technology that does not have the drawbacks of the trash rack is Bubble curtains; a technology that can deflect jellyfish away from the intake structure, be turned on and off at the flick of a switch, and one that only requires limited maintenance, most of which can be done from shore.

Bubble curtains work by pushing water in an upward and outward direction. This mixing action creates a current that pushes debris or jellyfish away from the curtain and out of the way of a water intake.

A Bubble Curtain using Bubble Tubing® Technology is comprised of four parts:

• The Bubble Tubing®
• Air supply line
• Control Panel
• Compressor

Bubble Tubing®: This proprietary hose of Canadian Pond.ca Products is engineered and designed to allow for maximum spread of air. Far from being drilled pipe, Bubble Tubing® has expandable holes that adjust to the air and pressure being applied to it. This gives the hose two very important properties:

1.It can create a uniform bubbling pattern with minimal airflow and pressure

2.It is biofouling resistant since the holes are not fixed and can expand to dislodge any growth

These two points are key to why Bubble Tubing® is the most cost-efficient solution. Bubble Tubing® requires little to no continuous maintenance since it has no mechanical parts, making it a very cost-effective solution.

Air supply line: Those come in wide varieties, but the main goal is to get air from the compressor to the Bubble Tubing®. Canadian Pond.ca Products mainly sells self-sinking hose to minimize the anchoring needs of the underwater components of the system.

Control Panels: Designed by Canadian Pond.ca Products, our control panels have valves and gauges to allow the operator to turn the system on and off from shore. These panels can be highly customized to fit your needs.

Compressors: The main driver of operation costs, it comes in various sizes and types. Electrical compressors are most costly upfront but less expensive for continual use, while diesel compressors are very portable and less expensive to purchase but consume fuel and require more maintenance. What sets Bubble Tubing® apart from the competition is that the tubing requires less air to make an efficient bubble curtain. In fact, we have seen estimates up to 20 times less air.

Canadian Pond.ca Products has partnered with various research groups to independently test its technology. One such partnership with the Canadian Marine Institute and C-Core Engineering has looked specifically at Jellyfish redirection.

In this study, a large flume tank was used to redirect simulated jellyfish to a specific location in the tank. Efficiency was calculated if the jellyfish was redirected successfully in a collector area of the tank. Multiple water speeds, airflows, and curtain angles were tested.

Results from these tests have shown efficiency around 97.5% for mild current conditions (0.1 to 0.3 m/s). Jellyfish that did pass through the current were directed towards the surface and away from potential intake locations. The reason for the passage of the few jellyfish seemed to be a function of geometry, rather than size, and it is expected that the bubble curtain would be more efficient on real jellyfish. Efficiency dropped when the current is above 0.5 m/s, where the efficiency of 53.3% was measured. Again, the upward push of the bubble curtain angles the jellyfish away from potential intake sites.

The above study results were then compared to Canadian Pond.ca Products proprietary Vel/o/city Bubble Curtain CFD model. These validation tests showed that the Vel/o/city model was able to predict, with high accuracy, the efficiency of Bubble Tubing® Bubble Curtains. This finding has allowed Canadian Pond.ca Products to begin offering its Vel/o/city CFD modelling service to customers wanting a Bubble Curtain for jellyfish mitigation.

Bubble Curtains using Bubble Tubing® Technology are an efficient way to prevent jellyfish fouling of intake screens. The Bubble Tubing® technology is a low-cost, low-maintenance alternative, therefore reducing plant shutdowns due to jellyfish. Canadian Pond.ca Products. is a leader in the Bubble Curtain field with 3^rd Party validated CFD models that can be used to ensure a successful installation.