Welsh Water

Welsh Water Weycocks Cross STW

Successful Trial for the Purchase of 2 x 5.5kW Aqua Turbo Submersible Flow Inducing Aerators

A major testing regime was carried out at Welsh Water Weycocks Cross STW by the Welsh Water Innovation Group using Aqua Turbo Submersible Aerators.

At this time the plant operated 4 Horizontal Rotors in their two Oxidation Ditches but due to major failures of the Rotors on a regular basis an alternative much simpler and Robust Aeration System was trialled.

Welsh Water Project Department designed and installed 2 Aqua Turbo 5.5kW AER-SL Aspirators complete with access platform and lifting frame.
The major advantages of the Aqua Turbo Submersible Aspirators are that they are direct drive, can be installed in situ without emptying the oxidation Ditches and can be accessed for maintenance easily. The Aqua Turbo Units are of Robust Construction and the special Screwpeller design does not rag up.

The Existing Rotors regularly have operational issues such as broken shafts, Gearbox of motor failures. Their design means that the Gearboxes are mounted on the shafts at very low levels in the ditches and below the bridges. Welsh Water Maintenance Engineers must work below their feet in very difficult conditions to access the gearboxes and motors. Also, once a rotor fails the plant struggles to meet DO and Gearboxes must be removed from site for repair.

The Aqua Turbo AER-SL units can be run using inverters giving the client greater flexibility and control of the Oxidation Ditch Process Performance. Utilising the Dissolved Oxygen Probes the Aspirators can run at various speeds during Peak and Low periods of Operation hence reducing energy costs.

Maintenance of the Aqua Turbo AER-SL is simple and can be carried out on site in situ and with Welsh Waters Excellent Design of Access Platform and Lifting Frame the 5.5kW units can be either replaced of maintained in a matter of a few hours without disrupting the site.

A spokesman for Welsh Water commented that all parties involved are extremely impressed with the performance of Aqua Turbo Submersible AER-SL Aspirators units during this extensive trial by the innovation group at Weycocks Cross Sewage Treatment Works. Since the trial was completed Welsh Water have utilised this design on several other Oxidation Ditch Works and are looking to roll this out as a template design for future Oxidation Ditches.