According to VTT, municipal sewage and some industrial waste waters could be used as sources of carbon and nutrients much more effectively than what is being done today. For VTT, waste water is a feedstock from which these substances can be extracted.
The research centre is currently promoting the idea with the help of the Resource Container project, which aims at small-scale waste water treatment solutions.
Studies by the Finnish Innovation fund Sitra show that the value of nutrients and carbon lost in waste water treatment in Finland is up to several million euros. Recycling these nutrients efficiently would reduce the nutrient burden that causes eutrophication and the harmful climatic effects caused by production of mineral fertilisers.
VTT has designed a Resource Container concept that consists of physico-chemical methods that are used or under development in the industrial sector. The focus of substance extraction will be specifically on the products, such as nutrients, bio-carbon and clean water, instead of on their disposal. The operating model does not include biological treatment, so it can be flexibly implemented.
“This year, we will test the concept at the waste water treatment plant of the town of Parainen,” says Mona Arnold, business development manager at VTT, in a release. “We also intend to study its functionality in archipelago conditions, where the challenge is to guarantee functional waste water treatment for a few dozen households and facilitate potential utilisation of the purified water, for example for irrigation.”
The results of the project will especially benefit municipal waste water treatment plants, technology suppliers, the chemical industry and producers of recycled nutrients and soil improvers.