A new technology for circular sludge settlement tanks in wastewater treatment has the potential to achieve major operating and energy savings for all UK water companies.
Launched in the UK by Hydro International, the ZickertTM Rotating Sludge Scraper is suitable for primary, humus and final settlement tanks. The scraper builds on the success of proven technology for rectangular tanks, achieving the same lower-energy and high-sludge performance.
The technology has already been successfully proven by wastewater treatment operators in Europe and builds on the reliability and high performance of existing ZickertTM technology. The new ZickertTM 3700 has undergone over 12 months of full scale operation internationally by the designers and developers, Nordic Water, with performance exceeding expectations.
In addition to new installations, the innovative scraper offers the utilities a widespread retrofitting opportunity - 90% of sludge settlement tanks are estimated to be circular in the UK.
Keith Hayward, UK Sales and Marketing Manager for Hydro Wastewater. commented:
“The ZickertTM Rotating Sludge Scraper is a unique concept in scraper technology with great potential to upgrade the UK’s installed base of circular tanks, delivering significant advantages in through-life operating costs as well as odour control.”
“Traditional rotating bridge scrapers need frequent service and maintenance. They can also be prone to wear and mechanical breakdown. Now a new way of removing sludge without a bridge or moving electrical connection point has been developed and proven.”
The ZickertTM 3700 features an innovative peripheral drive and rotating scraper design. The electrical drive is located on the perimeter tank wall with a static electrical connection point meaning no sliprings are needed. The bottom scraper blades of the new ZickertTM3700 are rotated via a circular ladder rail inside the tank wall, moving settled sludge to the collection point.
Where surface scum has to be skimmed off, the scraper frame is equipped with an additional top blade which directs scum to a scum beach and trough on the tank perimeter. With few moving parts, the complete ZickertTM 3700 installation is easy and inexpensive to maintain.
By removing the need for a bridge, a lower profile design is achieved which reduces the space under odour control covers, so there is less air to be purified.
In the UK, the new ZickertTM3700 launch will build on ZickertTM rectangular installations already in place at a number of major water companies, including Thames Water, Southern Water, Anglian Water, Scottish Water and United Utilities.
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