Master’s thesis proposal: Pilot experiments for extended nitrification with a biofilm process

Do you want to gain knowledge and experience in biological treatment processes and how research and development on new process solutions is carried out, as well as insights into the operation and management of a wastewater treatment plant? This might be the right master's thesis proposal for you.

Background

VA SYD operates 16 wastewater treatment plants that are treating wastewater from more than half a million people in southwest Skåne. Several of them will soon require new environmental permits, which will mean stricter demands regarding which concentrations of pollutants that can be discharged. For discharge of treated water to particularly sensitive recipients, it can be challenging to achieve the allowed levels of ammonia nitrogen. Today’s treatment plants are often not designed to reach such low concentrations, and using existing technology would require large areas and volumes. In addition, the highest peak flows are often bypassed the biological treatment, which contributes to the emissions. The lower the permitted effluent concentrations, the more important to also treat as much of these peak flows as possible.

At Ellinge wastewater treatment plant, VA SYD is carrying out pilot trials to investigate a new process for achieving low ammonia concentrations. Wastewater that is treated with a conventional biological process is further treated through post-nitrification with suspended biofilm carriers in so-called moving bed biofilm reactors (MBBR:s). The trials will to increase knowledge about how a compact treatment process can contribute to achieving future stricter demands for ammonia through additional biological treatment. Successful trials may lead to scaling up of the process and implementation at one of VA SYDs treatment plants.

Aims and objectives

The aim is to increase the knowledge about how a compact biofilm process can be designed, operated and controlled. The goal is to compare the nitrification capacity of two biofilm reactors with different operating modes, where one is periodically exposed to higher load and higher concentrations of pollutants. The nitrification rates will be determined with and without prior biological treatment of the wastewater.

The student will gain knowledge and experience in biological treatment processes and how research and development on new process solutions is carried out, as well as insights into the operation and management of a wastewater treatment plant.

Methodology

An existing pilot plant consisting of two parallel 15-liter reactors with suspended carriers will be used. The pilot plant has automated control of pumps and samplers. Monitoring is carried out through laboratory analyses of the water quality with regard to ammonium, nitrate, nitrite, total nitrogen, total phosphorus and with online instruments for dissolved oxygen, pH, ammonium/nitrate, etc. The work includes monitoring of the pilot plant, laboratory analyses, data analysis and evaluation and report writing.

The project will be carried out at Ellinge wastewater treatment plant in Eslöv, located about 2 km from Eslöv train station.

Contact

If you are interested or want to know more, please contact:
Simon Bengtsson, VA SYD: simon.bengtsson@vasyd.se
Michael Cimbritz, LTH: michael.cimbritz@ple.lth.se