Post-treatment for a novel wastewater treatment process
Municipal wastewater treatment plants (WWTPs) are facing stricter effluent requirements expected from the future EU wastewater directive. Meanwhile, it is desirable to decrease the utilization of resources and energy.
Background
A novel process for biological wastewater treatment called CELLA™ is being developed, where microorganisms grow as biofilm on bio-based carriers and remove organics and nutrients from the wastewater. It can be applied for both enhanced biological nitrogen and phosphorus removal. The influent wastewater composition and its content of easily degradable organics is important for a well-functioning denitrification (nitrogen removal) and enhanced biological phosphorus removal (EBPR).
In the ongoing pilot project FramBliK, VA SYD, Sweden Water Research and AnoxKaldnes (Veolia Water Technologies) combine a novel pre-treatment with the CELLATM technology to further enhance the process, and to minimise the use of both energy and chemicals. The pilot is operated at Källby WWTP (Lund). A post-treatment for the effluent from the biological nutrient removal is needed to capture particles, and to precipitate remaining phosphate. After this step, the wastewater should meet the effluent requirements to be let out in the receiving water. Since the post-treatment is not included in the pilot plant, it will be tested in the lab through experiments with different techniques. Coagulation and filtration as well as sedimentation and flotation are possible alternatives for the post-treatment.
Objectives
The aim of the master’s thesis is to evaluate the post-treatment and give advice regarding operational parameters with different techniques. The required pore-size and coagulant dosing in filtration, or the retention time which is needed in sedimentation or flotation are needed for the design of the post-treatment, and as basis for decision about the most viable technique for different cases.
Method
Treated wastewater from the pilot plant is collected on several occasions, and at different conditions regarding flow and operation. The wastewater is filtrated through different pore sizes both with and without coagulant dosing. Analyses are made of nitrogen, phosphorus and organic content (COD) in the wastewater to evaluate the reduction. A parallel master thesis “Carbon balance and energy potential for a novel wastewater treatment process” is planned during the same period, and the two projects can be done in cooperation and with synergy between the studies. The work will be carried out in Lund, both at AnoxKaldnes and at VA SYD.
Interested to perform this master´s thesis? Please contact:
Maria Piculell, AnoxKaldnes, maria.piculell@veolia.com
Elin Ossiansson, VA SYD, elin.ossiansson@vasyd.se