Project background and requirements:
Metal contaminants end up in storm waters e.g. from busy roads, industrial activities and construction sites. Even though the observed metal concentrations are not high they can accumulate in sediments and cause harmful effects to small aquatic ecosystems. Due to the nature of purification processes applied in wastewater treatment plants, metal contaminants mainly concentrate in the sludge. This limits sludge management options since sludge utilization (e. g. soil amendment) depends on heavy metal concentrations. Furthermore, growing demands from legislation and environmental aspects have forced industry to enhance their wastewater treatment processes. The development of sustainable storm/waste water purification solutions, e.g. based on biomaterials, are desirable due to their renewable credentials.
Another issue concerning urban waters are the nutrients contained in the treated sewage. In southern conditions willow wetlands are used as part of the main purification process or in the polishing phase in sewage treatment plants. However, efficient and suitable tree species should be found for wetlands in cold climate regions.
HuJa project aims to evaluate innovative solutions to the aforementioned issues.
The project has three specific goals:
- to increase metal removal from metal containing storm waters, treated wastewaters and industrial wastewaters using natural minerals and modified biomaterials (e.g. sawdust);
- to investigate how much can suitable tree species (e.g. willow) decrease nutrient (and metal) concentration of treated wastewater in Nordic climate conditions. Growth and suitability of selected species will be investigated when treated wastewater is used for irrigation;
- to identify, within the purification process applied in treatment plants, points where metal concentration of the wastewater can be cost-effectively decreased aiming at lowering the metal content of produced sludge. (Literature survey).
This project will provide crucial information about the type of natural materials and modification methods that are most suitable for effective removal of metals. Furthermore, it will clarify where in the purification process the materials should be applied for most cost/effective performance. The study will also create important knowledge regarding sludge management and wastewater purification in Nordic climate conditions by evaluating the suitability of willow wetlands.
HuJa project will run for a period three years (1.10.2015-30.9.2018) and the budget is 335 000 €. The project team is composed of researchers from three research groups from the University of Oulu: Water Resources and Environmental Engineering, Chemical Process Engineering and Environmental and Chemical Engineering. The project is mainly funded by European Regional Development Fund via the Centre for Economic Development, Transport and the Environment for North Ostrobothnia. Other funders and partners are: Outokumpu Chrome Oy, Oulun Jätehuolto Oy, Pudasjärven vesiosuuskunta, Taivalkosken Vesihuolto, Oulun Vesi, Pölkky Oy, Kuusamon Energia- ja Vesiosuuskunta, Naturpolis Oy, City of Kuusamo, Vesilaitosyhdistyksen kehittämisrahasto, Maa- ja vesitekniikan tuki ry., Ranuan Vesihuolto Oy, Napapiirin Energia ja Vesi Oy, Vesikolmio Oy, Aquaminerals Finland Oy and University of Oulu.
Water Resources and Environmental Engineering Research group
P.O. BOX 4300
90014 University of Oulu
E-mail: heini.postila (at) oulu.fi