Research at Cranfield University, in collaboration with Severn Trent and Microvi Biotech, is utilising the ability of bacteria to recover nutrients from wastewater.
The recovered product has the potential to provide a sustainable, green fertiliser alternative in the food sector and for the public’s use in gardens and allotments.
Rob Colston, PhD researcher, explains: “As we become more aware of the impact humans have on the planet, industries are now looking to minimise these negative effects. In the water and food industry, research into how we can close the ‘nutrient loop’ is developing rapidly as populations rise, with increasing food demand and waste production. Currently, we are extracting more nutrients from the earth to account for this and some nutrients such as phosphorus and potassium are finite.”
Nutrients can be recovered from wastewater using chemicals; however, this puts stress on other resources and itself demands more energy.
Bio-struvite is rich in phosphorus, ammonia, magnesium, and potassium and is produced by bacteria. It is a viable organic, slow-release fertiliser alternative to modern chemical fertilisers, slurry, and compost.
The requirements of this process are very low when compared to the chemical recovery of nutrients, thanks in part to the robustness of these bacteria and, therefore, reducing the energy demands within the water industry.
This recovered product has the potential to provide a sustainable, green fertiliser alternative in the food sector and for the public’s use in gardens and allotments, reducing the demand for imported and finite fertiliser products, closing our nutrient loop and improving our circular economy.
The research group is hoping to encourage the public to think about what is used to grow their food, where it has come from and the impact it can have. It is hoped that this will increase the number of potential end users as they switch to recovered fertilisers.
You can complete the survey here to help researchers understand how gardeners use fertilisers and their perceptions of recovered products. It is to encourage policy makers and suppliers to accept the use of these products on our road to becoming more sustainable.
Notes for editors
Estimates for phosphorus reserves depleting completely, range from 50 to 200 years. There is also an issue of where phosphorus reserves are: over 75% of known phosphorus reserves are in North Africa, with Europe accounting for less than 5% of the global reserves, putting it in an unstable position when it comes to securing fertilisers and to ensure food security. Therefore, to reduce our reliance on imported fertilisers we need to close the nutrient loop at home.
About Cranfield University
Cranfield University is a specialist postgraduate university that is a global leader for education and transformational research in technology and management.