Welcome to another Technology Update, in which we discuss new technology and other news in the Water Industry!
UK slowly increasing wastewater discharge quality
Welsh Water, a UK drinking water company, has published a plan to invest £3.6 million ($4.6 million) in an upgrade to one of their sewage treatment plants. The technology to be used has not been published but it is likely that this is done by precipitation using metal salts. See more in our dedicated article on Phosphorus Removal.
This investment comes shortly after a report from Water UK, detailing the need for further reduction of micropollutants (such as medicines and pesticides) from wastewater, indicating that the UK is slowly turning towards improving its sewage discharge standards.
Dutch Water Company Recovering Phosphates
Related to the UK news, a Dutch water company has set up a trial project to recover Vivianite (hydrated mineral iron phosphate) from wastewater, called ViviMag. Technology company Wetsus developed the technology, which uses iron salts to precipitate out phosphates from the wastewater. The resulting precipitate is normally dried and discarded, but due to vivianites paramagnetic abilities, the material can be easily recovered using strong magnets.
The recovered vivianite is sold as fertilizer or, since it is bright blue, it is sometimes used as colouring agent and can therefore be sold as such. Wetsus has confirmed they expect the vivianite to cover both OPEX and CAPEX. Find the article here (Dutch).
Image by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons
Veolia and PFO Africa to Run Ivory Coast Drinking Water Treatment Plant
Veolia and PFO Africa, the comany behind the Bouaké drinking water plant, have signed a 15-year operating and maintenance contract with the Ivory Coast government.
The La Mè drinking water treatment plant project in Abidjan, Ivory Coast, started in 2018 and has recently been completed, producing 240,000 m3 drinking water every day supplying 2.4 million residents.
Image credit Veolia.
Arkansas WWTW Separates Mixing and Aeration
A wwtw in Huntsville, Arkansas, has installed new mixers to separate their mixing function and aeration function in the final stages of the wastewater treatment works. Due to changing wastewater quality, the plant’s mixers were over-oxidising their water, leading to oxygen in the anaerobic and anoxic zones. The new mixers provide less oxygen and leave the aeration ditch to do its job, showing the crucial importance of proper oxidation in wastewater treatement.