Fine bubble aeration is a popular method of lagoon-based wastewater treatment due to its superior oxygen transfer efficiency. Our MARS aerator adds a coarse bubble static tube to fine bubble diffusers to combine that oxygenation efficiency with turbulent mixing.
Sometimes, though, lagoon mixing isn’t necessary or desirable. For that reason we’ve developed the AeroHub Fine Bubble Lagoon Aerator, an efficient fine bubble only aerator that provides the benefits of fine bubble lagoon aeration while eliminating many of its drawbacks.
Read on to learn the benefits of fine bubble lagoon aeration and how to determine when the AeroHub is the best aeration technology for a particular application.
Benefits of Fine Bubble Lagoon Aeration
Aeration efficiency is a function of bubble size and aerator depth. A flight of small bubbles has more surface area than the same size collection of larger bubbles, allowing them to transfer more oxygen to water. Also, smaller bubbles rise more slowly than larger bubbles, increasing the contact time between the bubble and the water column. Following are some of the benefits of fine bubble lagoon aeration:
- Energy efficiency: Very few aeration technologies can compete with the fine bubble in terms of energy efficiency: a Standard Aeration Efficiency (SAE) of 4–7 lbs of oxygen per horsepower hour. In many cases, switching from surface aeration or coarse bubble aeration can save anywhere from 40–60% (or more) on energy costs.
- Improved Dissolved Oxygen levels: Fine bubble aeration can achieve Standard Oxygen Transfer Efficiencies (SOTE) of 1.8–2.2% per foot of submergence, much better than most other types of lagoon aeration. A fine bubble aeration system will provide noticeable increases in dissolved oxygen levels.
- Fewer motors to maintain: In comparison to surface aerators, a fine bubble aeration system will likely have fewer motors to maintain. For example, where a typical surface aeration system may have 5–10 surface aerators, a fine bubble system will typically only have 2–3 blowers. Moreover, these motors are more easily accessible as they are onshore. This cuts down on maintenance time, materials, and hassle.
AeroHub Fine Bubble Lagoon Aerator Features
Like the MARS, the AeroHub Fine Bubble Lagoon Aerator is robust, portable, and easy to install. The patented central hub design provides the necessary strength for multiple maintenance cycles in addition to providing a portable platform for easy installation and maintenance. AeroHub connects to an onshore blower via laterals or an individual weighted air line and simply drops in—no need to disrupt treatment or take the lagoon off-line.
- Robust monobody design: Each aerator is precision machined out of a single block of PVC, so there are no points of weakness like seams or welds that can crack or leak.
- High efficiency, self-cleaning EPDM membranes: EPDM membranes provide a high Oxygen Transfer Efficiency (OTE). The membranes are also designed to be self-cleaning, lowering the risk of fouling that can lead to diminished oxygen transfer over time. AeroHub can also be specified with silicone or polyurethane diffuser membranes.
- Fouling preventive design: The unique design of the AeroHub positions the fine bubble diffusers 9” above the bottom sediments to avoid the clogging and fouling that have plagued conventional fine bubble aerators.
- Anti-clogging self-checked diffusers: AeroHub’s fine bubble diffusers are specially designed with anti-clogging technology with positive backflow sealing, which prevents the backflow of water and debris into the unit and unnecessary maintenance.
- Flexible weighted tubing: Each AeroHub is connected to the air header via flexible weighted tubing or plumbed directly as per the application requirements.
- Easy handling: AeroHub is weighted on site, which makes it easy to handle and less expensive to ship.
Triplepoint’s AeroHub Fine Bubble Lagoon Aerator is available with four, six, or eight diffusers, so there is an AeroHub model for virtually any lagoon or basin application. Designed for peak efficiency, the AeroHubs are installed so their areas of influence don’t overlap. This keeps the efficient fine bubbles from coalescing into coarse bubbles.
Most lagoons benefit from robust mixing, which keeps solids in suspension and the food, the bugs, and the DO in constant contact to maximize treatment. In fact, the EPA considers mixing a critical component of aeration.
However, there are some applications for which mixing is unnecessary or undesirable:
- Shallower lagoons, generally 6 feet deep or less
- When more points of energy distribution are required to spread oxygenation throughout the lagoon
- When turbulent mixing isn’t wanted or needed; for example, to avoid disturbing settled solids
Triplepoint: Your Lagoon Aeration Specialists
Whatever your lagoon application, we can help you design a lagoon aeration system to maximize treatment, mitigate odors, and improve energy efficiency. Send us your specs—we’d be happy to send you a no-obligation quote.