Research begins into using sewage to clean water bodies
While Britain continues to grapple with a water pollution crisis, one team in Scotland believes waste streams could actually improve aquatic habitats.
In a project funded by the Industrial Biotechnology Innovation Centre [IBioIC] and Scottish Water, researchers have begun working on the viability of a water filter created from biochar produced when sewage sludge burns at a high temperature while being deprived of oxygen.
Testing is now underway at the Waste Water Development Centre in Bo’ness, and if successful could help to a long-overdue ‘revolution’ in water management. Currently, around 130,000 tonnes of human waste from the sewage system are incinerated or recycled into the land in Scotland alone. This comes at a cost of £6million.
Trials have already shown that filtration systems made from biochar can remove large amounts of phosphorus, a key contributor to algal blooms which occur when excess waste water is present at a location. Use at scale could therefore prevent these blooms from forming, contributing to improved environmental, animal and human health.
Benefits from the project may not end there, either. Naturally-occurring phosphorus is currently depleting, and the IBioIC-Scottish Water project has the potential to introduce a new supply for collecting the mineral, which is vital for the production of products ranging from cleaning products to fertiliser.
‘While phosphorus causes challenges for the environment and sectors such as aquaculture because of its impact on algal blooms, it is also an element that we all use in everyday products,’ said Dr. Szabolcs Pap, the project’s lead academic. ‘Natural stores are depleting, so this circular bioprocess could lead to new opportunities to recover the nutrient from wastewater and create new supply chains here in Scotland.
‘At the same time, water companies are under increasing pressure to reduce waste and find alternatives for bioresources from sewage, so there is an additional benefit in terms of sustainability,’ she continued. ‘Biochar can be a valuable material with a range of potential applications, but the global market is still in its infancy. The approach to recovering phosphorus we are exploring in this project is just one example of what it can be used for.’
The next phase of the trials – which also involve experts at the Environmental Research Institute at UHI, North, West and Hebrides are providing insight into biochar in filtration systems, supported by water treatment specialist, AL-2 Teknik – will see the research move on to smaller treatment works in Scottish Water’s estate.
‘This collaboration demonstrates how one type of waste can be used for the benefit of the natural environment, treating issues like algal blooms which are posing significant challenges as climate change continues and water temperatures rise,’ said Dr Liz Fletcher, Director of Business Engagement at IBioIC. ‘Although the creation of biochar is still in its infancy, we see huge potential for a growing market that could help several industries to reduce waste and adopt more circular processes.’
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Image: IBioIC