Alla artiklar

The microbial transformation of ammonia to nitrate, the nitrification, is a central process in the nitrogen biogeochemical cycle. In a modern wastewater treatment plant, the nitrification process is a key process in the removal of nitrogen and inhibitory compounds in sewage can seriously affect the nitrogen removal. A major sewage cleaning plant in the southern […]

Increasing discharge demands put higher pressure on process optimisation and control of the wastewater treatment plant performance. For evaluation and regulation of the process performance, oxygen uptake rate (OUR) measurement is a useful tool. In this paper one way to perform oxygen uptake rate measurements is described. Possible applications of the method for wastewater treatment […]

In conventional wastewater treatment plants the aeration of the biological treatment process is often one of the largest energy consumers. As a part of making Käppala WWTP more energy efficient three full-scale optimization experiments of the biological treatment process have been performed. In this article, the different strategies are described and evaluated and the results […]

In wastewater treatment applications the MBR technology combines biological treatment and a membrane system to provide organic and suspended solids removal. Installation of low-pressure membranes within a biological reactor system replaces sedimentation, screening and media filtration as means of separating mixed liquor suspended solids (MLSS) from treated wastewater. This study is focused on experiments with […]

Leachate constitutes the main potential long-term environmental risk of landfill emissions. The objective of this work is to identify the extent of major external influences on conductivity monitoring data and its implications for future monitoring programs. Data from three landfills in Sweden has been evaluated with the help ofmultivariate data analysis. With the aid of […]

Swedish wastewater treatment plants’ energy usage equals a total of 0.6 TWh per year. Together with the Swedish drinking water treatment, the usage corresponds to approximately 1 % of the total electrical energy consumption in Sweden. Potentials for a reduction of this usage do exist. However, very modest efforts for energy usage conservation are attempted.In […]

The numerical model CE-QUAL-W2 was used for exploring hydraulic measures to minimize the water quality problems experienced by the water works at Aurevatn reservoir, Baerum municipality, serving sixty thousand inhabitants with potable water. The dystrophic nature of the reservoir water is reflected by high values for colour and total organic carbon. The composition of phytoplankton […]

During autumn year 2000 a severe flood hit the Byälven river system in the western parts of Värmland, Sweden, causing damages of about MEUR 25–30. Afterwards local municipalities and the county board decided to investigate the possibilities of mitigating future floods and initiated the Byälven Project. What caused the flood and a number of flood […]

An onsite wastewater treatment plant at Brändön, north of Luleå, receiving primarily treated wastewater from a village, was operated and investigated during one year. The wastewater flow was 0.5 m3/d. The main treatment steps were a prefilter, mainly to distribute the flow, a vegetation filter consisting of two different clones of Salix and two phosphorus […]