Water & Wastewater Treatment

What is it? The WEARS Resmix Vital, supplied by Gurney Environmental, is a floating impeller system for circulating the treated, potable water in storage reservoirs. Designed for reservoirs of up to 200 megalitres, a locking system allows its four blades to swing up vertically to allow it to be lowered into covered reservoirs through a roof hatch. Once inside, it floats on the surface of the water, where its axial flow pump pushes water down and around the tank. What's innovative about it? Circulating the potable water in storage reservoirs is desirable because it prevents thermal layers from forming, which can degrade water quality; it also helps disinfectants such as chlorine over 12 years of R&D and made by WEARS, an Australian company; it is used in impounding reservoirs containing raw water. Following demand from water companies in the UK for a similar system for storage reservoirs – which could fit through a standard 650mm hatch - the Resmix Vital was developed as an 'off-the- shelf' product and received DWI approval last year. Who is using it at the moment? While only recently launched in the UK, South West Water are already using it, and there has been interest from several other water utilities. Internationally, it is being used by water authorities in Qatar and Australia. What associated technologies are available? The ResMix 5000, which comprises a 5 metre diameter axial flow pump, is the larger version which is used in raw water reservoirs. Innovation Zone is a new WWT feature aimed at highlighting innovative technology within the water sector. Suggestions for future inclusions to: jamesbrockett@fav-house.com. spread through the whole tank and prevents fine solids from settling on the bottom. Existing systems used for this purpose are typically fixed at the reservoir bottom and use compressed air or suction to create a current. The Resmix does the job from the surface, meaning it is effective whatever the water level; it also uses much less energy than conventional solutions. What benefits does it bring? The Resmix has been shown to be more effective than other solutions at creating a current that reaches into all corners and walls of the tank, preventing biofouling on surfaces and minimising disinfectant decay. The reliable circulation means there is no need to erect physical barriers such as baffle curtains to tackle 'short-circuiting' in the current. The fact that chlorine and fine solids remain suspended means that there is a reduced need to enter the tank for desludging, and no need for additional chlorination. It requires minimal scheduled maintenance and uses one-twentieth of the energy of conventional systems. How was it developed? The original Resmix was developed Innovation zone l This month, we look at a system that circulates the water in potable reservoirs, avoiding the quality issues that come with stale, aged water sitting in the corner of tanks Resmix Vital Floating axial flow impeller system The Resmix Vital's blades retract so it can fit through the hatch of a covered potable water reservoir 30 | FEBRUARY 2016 | WWT | www.wwtonline.co.uk

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