Environmental benefits from resource reuse
Water management is fundamentally a circular business. Every drop is endlessly used and reused, and this circularity is already evident in the sector in initiatives such as recycling wastewater for reuse and capturing biosolids for agriculture.
However, water utilities need to collaborate further to realise circular economy opportunities.
That’s according to Rich Walwyn, head of asset intelligence and innovation at Severn Trent, who made an impassioned call during a recent Water Action Platform webinar.
“We believe it is an essential ingredient in meeting the supply and demand challenges that we’re going to face over the next 20 to 30 years and maximising value for our customers through the recovery of some of the by-products of our processes,” he told attendees.
“Forming effective collaborative partnerships is key to maximising the opportunities that a transition to a circular economy brings. We’re really keen to explore opportunities to work with like-minded organisations on identifying cross-sector solutions and accelerating our plans.”
Three technologies from Europe and North America which facilitate recovery of cellulose from toilet paper, phosphorous removal and energy storage were highlighted in the webinar, hosted by Piers Clark, chairman of Isle Utilities.
Paving the way with cellulose recovery
Coos Wessels, technical director of CirTec, explained how the Netherlands is quite literally paving the way in creating infrastructure from recycled toilet paper.
Recycled toilet paper pellets have already been used successfully as road-building material in the province of Friesland, to reinforce a dyke and pave the parking lot of a children’s petting zoo.
Dealing with sludgeis expensive for water companies, and those costs could be reduced by initiatives like the Cellvation project, which extracts cellulose from wastewater.
The recovered cellulose fibres are sterilised, dried and made into pelleted products known as Recell – which can be used in industries such as construction, pulp and paper, coatings and sustainable chemicals.
Biogas enrichment with power-to-gas energy storage
Based in the US and Germany, Electrochaea has a solution for one of the most pressing challenges facing energy systems - the integration of fluctuating renewables into the electricity grid.
The company’s proprietary BioCat power-to-gas energy storage concept converts renewable electrical energy into chemical energy, in the form of methane. By converting water into hydrogen and oxygen through electrolysis, they can enrich raw biogas.
“What’s unique is our biocatalyst is a patented strain which is optimised to generate a lot more methane and do it more efficiently,” said managing director, Dr Doris Hafenbradl.
In addition, the oxygen generated during the first electrolysis step can be used to enhance the secondary wastewater treatment stage, and the bio-methanation process is exothermic, meaning that it generates heat – which can be used to heat the sludgebefore digestion.
Creating a closed-loop for phosphorus management
“If you ask a water manager or regulator about phosphorus, they will describe it as pollution and as a result spend a significant amount of money every year preventing its discharge into water,” said Matt Kuzma, the vice president of Canadian nutrient recovery solutions company, Ostara.
The company has created a closed-loop solution for phosphorus management using Pearl, a process technology which recovers valuable nutrients from wastewater, transforming them into high-performing, slow-release fertilisers that increase yields and reduce pollution runoff.
A circular pitstop on route to Net Zero
With the UK water sector launching a world-first Net Zero Routemap in November, there is clearly a drive for utilities to play a key role in protecting and enhancing the environment.
The newly published Routemap sets out a broad range of opportunities, initiatives and projects that will help the sector cut millions of tonnes of carbon emissions by 2030 – many of which focus on resource reuse, including:
- Making even more use of renewable energy by generating enough solar and wind power to meet 80 per cent of the water sector’s electricity demands
- Producing more biogas from sewerage waste, which can be injected into the grid to heat homes or used as an alternative fuel for transport
- Using advanced anaerobic digestion for sewage treatment to reduce process emissions.