70% of storage tanks suffer from poor mixing
As cool, dense water enters from the inlet pipe, it settles on the bottom of the tank while the warmer, more buoyant water already present in the tank rises to the top. This temperature difference means that very little natural mixing occurs – causing even the best water quality to deteriorate before reaching customers. Active tank mixing is used to overcome the following water quality challenges.
Thermal stratification and high water age cause residual loss, bacterial growth and public health risks. Active mixing combats thermal stratification and makes optimal use of existing disinfectant residual. This reduces the need to dose the tank.
Disinfection Byproducts and Regulatory Compliance
The Stage 2 DBP rule is forcing utilities to achieve better disinfection while reducing DBPs. Mixing ensures that treated water entering the tank is uniformly distributed and residual loss is minimized so there is less bacteria growth and DBP formation.
In chloraminated systems, warm temperatures lead to disinfectant loss and ammonia buildup – creating nitrification. Active mixing keeps water temperatures consistent, inhibiting disinfectant loss and preventing nitrification episodes.
Ice formation inside tanks can cause significant damage to tank coatings and internal hardware, even tank rupture. By keeping temperatures above freezing throughout the tank, active mixing eliminates ice formation and damage.