August 11, 2021

Tenure track researcher Marika Kokko: “More circular economy thinking needed in the field of water technology”

Marika Kokko, a KAUTE foundation grant recipient, is researching the recovery and recycling of nutrients in wastewater. The recovery and recycling of nutrients reduces the burden on the environment and can increase Finland’s self-sufficiency.

The desire to promote the well-being of the environment initially led Marika Kokko to study environmental technology. She already knew in high school that she would like to do work that could concretely affect the state of the environment.

Kokko found research a way to promote her goals. Today, she is a tenure track researcher in bio and circular economics at the University of Tampere. Among other things, she studies the treatment of urban wastewater and sludge, and the recovery of nutrients in them.

Nutrients, such as phosphorus and nitrogen, are used, among other things, in fertilizers for food production. However, if used too much, they are harmful to the environment.

Finland is dependent on other countries for the production of some nutrients, such as phosphorus. Phosphorus is a non-renewable raw material with limited reserves worldwide.

“If nutrients can be recovered for example from municipal wastewater, we can both reduce eutrophication of water bodies and increase our self-sufficiency”, says Kokko.

Cleaner recycled fertilizers locally

Pirkanmaa offers an excellent location for Kokko’s research, as there is a lot of enthusiasm in the area for developing wastewater treatment. Kokko has collaborated on nutrient recycling with for example Nokian Vesi and Pirkanmaan Jätehuolto.

With a grant from the KAUTE foundation in 2019, Kokko is involved in a project to develop ways to treat locally collected municipal wastewater in the Hiedanranta area of Tampere.

Vacuum toilets have been installed at Lielahti Manor in Hiedanranta, where toilet waste can be recovered and nutrients separated from the waste at the place of origin. The aim of the research project is to find out how vacuum toilet products, so-called black waters, and biowaste can be treated, and how nutrients can be recovered from them locally.

Concentrations of locally collected nutrients are very high compared to toilet waste travelling long distances to other wastewater treatment plants with other wastewater, such as wash water.

“Higher nutrient concentrations make it easier to recover nutrients. In addition, there is less of certain impurities in locally collected toilet waste. This can contribute to the production of cleaner recycled fertilizers”, says Kokko.

From the circular economy boost for self-sufficiency

Research in water technology and wastewater has generated a lot of good practices that guarantee for example access to clean drinking water and the treatment of wastewater in an environmentally safe manner. According to Kokko, the next step is that the field should have more circular economy thinking.

“It is important to find out how nutrients can be recovered safely and how CO2 emissions from wastewater treatment plants can be reduced at the same time. Local recycling of nutrients for food production could be of great benefit in the future if we face situations such as the corona pandemic, which require self-sufficiency”, says Kokko.

“In water technology, we always have to find better ways for the environment to do things.”

Promoting the circular economy in water technology can also provide business opportunities, for example in the form of the development of new technologies. According to Kokko’s experience, the best results come from cooperation between different parties.

“It is motivating to cooperate with other actors in the field and to see in practice how things are going.”

Kokko’s desire to work for the environment has not waned over the years, on the contrary. It still remains one of the researcher’s greatest sources of motivation.

“Although there are good practices already in place, it doesn’t mean that they shouldn’t be further developed. We must always find better ways to do things for the environment”, she says.

”Stories from water technology research” series of articles presents the work of researchers funded by the KAUTE Foundation and the Erkki Paasikivi Foundation. The foundations will organize a joint grant application focusing on water technology research yearly on August-September. The grants are primarily awarded for doctoral dissertations or for post-doctoral research. The foundations also encourage other organizations in the field of water technology to cooperate in the field of grant applications.