Tank – Water Mixing Systems
The most important element of any water tank is the mixing system, which can be a passive or active unit. Passive mixers require a drain and fill cycles, while active mixers keep the tank mixed all the time.
Typically, these tanks have fairly small access openings in their top walls that are designed primarily to permit one worker to pass through to inspect or repair the interior of the tank.
Tank-water mixing systems completely mix potable tanks to ensure consistent disinfectant residuals, eliminate thermal stratification and deterioration and keep all the water in your tank of an appropriate age. This makes it easier to monitor and verify water quality and, when required, add a boost of chlorine or other disinfectant.
The GridBee and SolarBee mixers are designed to circulate potable water storage tanks up to 100 million gallons with very little power due to the minimal lift (head) pump design. Powered by solar energy and deep cycle battery backup, this equipment can operate around the clock.
Active mixing is a more sustainable and cost-effective alternative to passive mixing. It provides operators with more mixing power, independent of drain and fill cycles, and can be easily removed for tank inspections and maintenance.
The US EPA recently announced new rules for minimizing the formation of disinfection by-products (DBPs). Chlorine and chloramine introduction have long been known to produce significant DBPs.
In particular, the formation of nitrite from free ammonia is one of the more common DBPs to be found in chloramine-treated water systems.
To prevent these types of problems, a system needs to be capable of thorough top-to-bottom tank mixing and, as an added bonus, able to quickly circulate large volumes of disinfectant throughout the entire water column. In the case of a Tankproinc system, this is possible with a solar-powered circulation system that was invented to meet the EPA’s latest requirements for tank water quality management. The company’s patented technology allows for the most effective top-to-bottom mixing while also delivering other water quality benefits, such as reduced energy costs.
Ice formation in water tanks is a serious problem for utilities in colder climates, especially since they often are made from metal. Ice chunks can move across the tank’s surface, causing structural damage and leaking water.
Thermal stratification in potable water storage tanks is also a challenge. During warm weather, newly treated cold water won’t mix well with the hotter, more recent water in the tank. The result is distinct temperature layers that can lead to a host of problems including higher residual disinfectant loss, bacteriological contamination, and more biofilms.
A properly designed and installed active mixer, such as the CertiSafe Tank Mixer from Kasco, can prevent thermal stratification year-round. The device is easily removable for inspection and maintenance. Its other impressive feats include preventing ice formation, distributing the most notable tidbits in the most uniform way possible, and keeping it all flowing on the least amount of energy.
In a typical municipal drinking water tank, power consumption is generally the largest energy consumer in a facility. For example, a typical standard design criterion for flow equalization basins states that an air supply rate of 30 cfm per 1000 ft3 of mixing tank volume requires approximately 1.5 horsepower input to mix the water.
Active water mixing systems use a motor-driven impeller to continuously circulate water inside the tank, regardless of how full it is. This means less power is needed to mix and maintain a homogeneous water quality, which in turn lowers the energy consumption of your water treatment plant.
Tank-water mixing systems use a motor-driven impeller to continuously circulate the water inside your water tank, regardless of its size. This setup eliminates the need for additional nozzles, piping, and other moving parts to be installed inside your tank, which helps reduce maintenance costs and can be easily removed for inspections and repairs.
Another feature of the near-laminar flow mixer is that it floats on top of the tank’s water without creating turbulence, which keeps the water at a consistent temperature throughout the tank. This feature helps to maintain effective chlorine residuals, eliminates the risk of biological contamination, and prevents ice from forming on the sides and top of your tank in winter. In addition, it helps to minimize power consumption. This makes it a very sustainable option, especially for municipalities that are looking to lower their energy bills.