Meeting phosphorus removal targets is one of the greatest challenges facing the water industry today, so in this issue, we speak to Andrew Bibby of water and wastewater treatment specialist Bluewater Bio, about why it is a priority and how best to meet the challenge.
Phosphorus is found in many everyday items that we rely on in our daily lives and in certain circumstances its presence is a good thing. Phosphorus is a nutrient that increases plant growth, helping us to grow plentiful food crops, yet when it comes to our natural water courses, its presence is a grave concern, as in excess it has such a detrimental impact on aquatic life and systems.
To protect our aquatic heritage for future generations and to ensure we have a safe, ready supply of water today, phosphorus removal is key. This pressing need is underpinned by UK regulations and the European EU Water Framework Directive, which sets out water quality goals which must be met.
“The more stringent limitations on phosphorus levels being set currently makes the challenge even greater, and consequently, the technology traditionally used to meet the targets is no longer sufficiently effective.
“The satisfy today’s and future needs for fine particulate solids removal, media depth is king, but to gain best filtration performance, you need to be able to utilise all the media depth effectively, and conversely clean the captured solids from the media equally as effectively when needed. FilterClear is a high rate multi-media filtration technology that incorporates media particles in a variety of sizes from coarse to fine, and also different densities, light to heavy. In filtration mode, the effluent passes through the coarse to fine media, the finer heavier media at the base of FilterClear capturing the finest particles. In backwash mode, the media is completely fluidised by a combination of water and air scour to remove the entrained solids. At the end of the backwash cycle, the media naturally stratifies itself, lightest to heaviest, coarse to fine”.
“The benefits of FilterClear are numerous, primarily it achieves consistently higher quality of filtered water than alternative filtration systems, thereby enabling compliance with the new consent for phosphorus, under the Water Framework Directive”.
“In addition to this, it entails minimal operator intervention, less maintenance and less downtime – there are no moving parts, and longer running times (hours) between backwashes. Routine media chemical cleaning and media power washing are not a requirement of FilterClear which obviously has operational cost benefits along with minimising Health and Safety and lifting and access requirements. Consequently, FilterClear offers the lowest whole life cost compared to competing technologies”.
“In terms of iron dosing for phosphorus removal; FilterClear benefits from finer pin head flocs which can penetrate the full depth of media. A simple in-line static mixer is used to thoroughly disperse the iron dosage, additional tanks and mechanical mixers and the associated footprint are not required. The combination of the efficient iron addition and the efficacy of the FilterClear to remove particulate phosphorus solids means we can achieve very low phosphorus levels in a single stage compact process. Using DfMA principles, a typical plant can be unloaded at site, positioned and installed within a day”.
In addition to phosphorus removal, FilterClear has a number of other applications, including the tertiary filtration of wastewater, as at Anglian Water’s Bugbrooke Water Recycling Centre, and for desalination pre-treatment, as installed at The King Abdullah University of Science and Technology in Saudi Arabia.
The system has been utilised in industrial processes too, like at Brookside Metals in Wolverhampton, where it reduced the environmental impact of their processes, whilst dramatically reducing their carbon footprint and water bills too. FilterClear has also been used as pre filtration stage to achieve potable water more efficiently at Loch Ascog, Scottish Water, and to harvest and reuse rainwater, as at Nirlon Knowledge Park, in Mumbai, India.
Bluewater Bio has a robust and demonstrable track record providing treatment systems to the water industry, working with companies including Severn Trent, South West Water and Anglian Water. What is telling about their work is not only the calibre of their clients but the repeat custom they have garnered from clients, reflecting the high regard in which they are held.
Earlier this year, for example, it was announced that Severn Trent had chosen FilterClear for the provision of a Tertiary Solids Removal plant at their Brockhampton facility in Gloucestershire, in addition to the installation they already had at Codsall, in the village of Bilbrook to the North of Wolverhampton. They have also recently secure d a third scheme with Severn Trent at Harby STW. A sure sign of confidence in the technology.
Meeting phosphorus removal targets is a priority for the water industry and new technology, like FilterClear, has demonstrable success at meeting those targets and at doing so at a lower cost too.