Screen technology improves sewage treatment efficiency

As part of its goal of providing high-quality, safe drinking water to households while at the same time finding ways to improve the management of wastewater, MidCoast Water is using band screen technology to improve efficiencies at its Dawson Sewage Treatment Plant (STP).

While MidCoast Water currently delivers sewerage services to 40,000 households in the Manning, Great Lakes and Gloucester communities, the number of homes requiring such services is predicted to increase to 58,000 by 2037. The utility aims to meet the needs of this growing population by constantly improving its systems and by adopting new technologies. One of these new technologies is the HUBER EscaMax Band Screen, designed specifically to process wastewater with high levels of solids and gross material.

The HUBER EscaMax Band Screen is used in the plant to screen and remove solids, fine material and plastics that would otherwise block equipment downstream. MidCoast Water chose the technology to replace and upgrade its existing screen system at the Dawson STP for three reasons: it is said to be the most efficient in the market; it removes the highest level of solids; and it is easy to retrofit.

The through-flow band screen uses a linked band comprising perforated stainless steel panels. The through-flow profile allows for flexible hydraulic conditions when compared to centre-flow types and allows easy integration within inlet works designs, particularly those incorporating downstream grit removal systems. It is a compact system that can be easily retrofitted into existing channels.

The product is particularly suitable for situations where good separation efficiency is required in deep channels with high water levels. Perforated screening elements are said to provide superior separation efficiency in comparison with slit screening elements.

Since Hydroflux installed the new technology, replacing the first of two screens, MidCoast Water has achieved a screen rate which is double that of previous screens. This is helping achieve major savings in the cost of maintenance.

John Koumoukelis, a director of the Hydroflux Group, said the HUBER EscaMax Band Screen technology will continue to replace other fine screen types because of its efficiency and because of the kinds of results being achieved at plants such as the Dawson STP.

“Once this technology has been installed to replace and upgrade previous systems, it is quite common to achieve screening captures of more than 80%,” he said.

Image credit: ©iStockphoto.com/Bart Sadowski