Chemineer top entry industrial mixers save energy in Anoxic Zones.

SAVE ENERGY (reductions up to 85% !!!)

The cost of energy is increasing, and there is ever more pressure to save energy in all areas of operations. Recent work into Anoxic zone mixing has demonstrated that top entry mixers with their highly efficient slow speed impellers provide not only a better flow pattern, and increased flow velocities in the base of the tank, but can do this with substantially less power. In a direct comparison the Chemineer design SC3 impeller uses 1.44 w/m3 whilst a submersible mixer required 10.2 w/m3 to achieve the required velocity profile in the tank base. Due to the size and quantity of mixers this results in thousands of pounds operational cost savings:-

Example of typical site – total volume of tanks 2861 m3

Chemineer option energy consumption
2861 m3 x 1.44 w/m3 @ 0.05 £/kW hr = £ 1,804 PA.

Submersible option energy consumption
2861 m3 x 10.2 w/m3 @ 0.05 £/kW hr = £ 12,781 PA

The flow pattern

The SC3 impeller is a high efficiency axial flow hydrofoil impeller. The flow is directed centrally downwards in the chamber and deflects radially outwards at the base of the tank. This scrubbing effect means that the base of the tank is kept clear and the solids are suspended. The flow pattern also shows that the surfaces velocities are reduced, and below a level where aeration could be a potential problem.

Targets

Base velocity - significantly over 0.3 m/s over 80% of the base area, to prevent deposition

Surface velocity - below 0.5 m/s to prevent aeration