Channel Mixers rapidly achieve a high degree of mix with extremely low headloss in very short lengths.

Complete mixing in the channel is possible, achieving a low CoV, over a wide range of flowrates. With headlosses of just a few millimetres feasible, gravity flow is an option, eliminating the expense of pumping, saving not just capital costs, but ongoing maintenance and energy costs too.

Channel Mixers can be installed in new treatment works or easily retrofitted into existing installations, even when flooded. The modular design concept, based on the STMC mixing elements, allows wide variations in aspect ratio (height/width) suitable for square or nearly square channel sections, narrow deep channels and wide shallow channels. Independent trials have established that the STMC concept is the most efficient of all known commercially available static mixers.

Open channels can develop unusual velocity profiles not found in conventional piping systems. Considerable investment has been made?in developing a procedure to ensure that the correct amount of additive is injected proportional to the local mainstream flowrate.

Applications include:

• Raw water blending
• pH control
• Rapid coagulant addition
• Polyelectrolyte dosing
• Residence time control

The high efficiencies and benefits of the channel static mixer apply to any scale, the largest installed to date is 7m wide x 5m deep, handling 7 tonnes/sec of water.