TalTech scientists develop technology to improve the quality of drinking water
ALCHEMIA EU LIFE program project aims to develop and demonstrate a cost-effective and sustainable technology for the removal of natural radioactivity in groundwater intended for human consumption.
The technology is developed by TTÜ scientists Anna Goi and Juri Bolobajev.
In many places of North Estonia the radiological parameter of groundwater used as a drinking water source exceeds 2-6 times the indicative dose set by the Estonian Regulatory Act. According to the data of the Estonian Health Board there are 190,000 consumers of the groundwater in North Estonia. Besides Estonia, natural radioactivity is also present in the groundwater of a number of European countries like Spain, Germany, Italy, Sweden and Finland as well as in the USA and some African countries.
The LIFE ALCHEMIA research project aims to develop the technology for the removal of natural radioactivity in water. The technology is based on the application of manganese dioxide to reduce radioactive compounds, iron and manganese content. The technology to be developed will substantially decrease the content of these compounds improving the drinking water quality.
Particles are removed from the water by filtration. The filter should be regularly washed and maintained.
Novel technology requires further development. The research is needed in order to elucidate the mechanism of the chemical processes, optimise the dose of manganese dioxide and select advanced filter materials with lifetime that is suitable for the effective removal of the hazardous compounds.
TTÜ scientist Juri Bolobajev has constructed the prototype of manganese dioxide-based technology. The scientist developed the prototype technology for the further improvement of drinking water quality. Prototype studies require less water and other resources than a properly designed pilot-scale study. The prototype set-up is fully automated and is operating 24/7.
The obtained results are planned to be applied for the adjustment of AS Viimsi Vesi pilot-scale set up. The drinking water of AS Viimsi Vesi satisfies all the drinking water quality standards. The aim of the further technology development is to reduce the water treatment operation costs.
As the chemical composition of the water is unique in the different regions, there is also no universal water treatment technology. Therefore, each water treatment plant should adapt the technology to the water composition.
Groundwater of North Estonia lies in the earth's crust at a depth of 60-70 meters. According to Anna Goi, a researcher at the Tallinn University of Technology, for water consumer is important to know that groundwater in the deep aquifer is highly protected against the pollution. Anna Goi answers the question of where radioactive substances reach the groundwater: "Radioactive compounds present in groundwater originate from uranium and, to a lesser extent, from thorium decay. These compounds are naturally released into the groundwater, i.e. during the rocks dissolution. The chemical composition of water is not only limited to elevated content of radioactive substances. In Estonian groundwater, the levels of ammonium, heavy metals and hydrogen sulfide often exceed the limits set in the drinking water standards. This in turn influences the choice of the appropriate treatment technology. The selection of technology and its adaptation is an art that is held by the experts of the Environmental Technology Laboratory. We cooperate with AS Viimsi Vesi and we are ready for cooperation with other water management companies."
According to the Health Board message, accidental health damage due to the content of radionuclides in the groundwater of the Cambrian-Vendian wells is unlikely. However, given the precautionary principle, in these regions, more attention should be given to infants fed with artificial food mixes. It is recommended to use bottled water to prepare baby food. The probability of harmful effects depends on several factors such as dosage, age of the organism and state of health.
The research project partners in Estonia are the Laboratory of Environmental Technology at Tallinn University of Technology, Institute of Physics at University of Tartu and AS Viimsi Vesi. The project is coordinated by the Spanish Technology Centre, Fundación CARTIF. Among other Spanish project partners are the Solar Energy Research Centre (CIESOL) and the Diputaciόn de Almeria (DIPALME).
The research is international - Tallinn University of Technology scientists and the specialists of AS Viimsi Vesi pass the experience to the Spanish partners.
The project page: www.lifealchemia.eu
Anna Goi, Tallinn University of Technology, Department of Materials and Environmental Technology, Laboratory of Environmental Technology, Phone: +372 620 4341; Anna dot Goi at ttu dot ee