Lakvattenkvalitet undersökt med multivariat analys / Leachate quality investigated with multivariate data analysis
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 […]
Energy conservation in wastewater treatment operation a case study at Himmerfjärden wwtp
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 […]
Modelling and hydraulic Management of a boreal reservoir system for mitigating nuisance agents in a public water supply – akershus, norway
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 […]
Projekt Byälven – efter översvämningen hösten 2000 / The Byälven project – after the flood of year 2000
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 […]
Nutrient recovery in a small scale wastewater treatment plant in cold climate
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 […]
Att dimensionera vattentorn / To design water towers
The article discusses how knowledge has been accumulated by water engineers for optimizing the size of water reservoirs in drinking water supply systems. The most important knowledge for proper sizing has always been to know the water demand. How much water is consumed per day in the net-work? Second most important fact is the production […]
Pre-treatment of wastewater sludge before anaerobic digestion – Hygienisation, Ultrasonic treatment and Enzyme dosing
Pre-treatment of sludge before anaerobic digestion can increase methane production and degradation of organic matter. There are various pre-treatment methods for this purpose. Anaerobic digestion tests were performed for comparison of three pre-treatment methods (hygienisation, ultrasonic treatment and enzyme dosing) usedseparately or in combination on biosludge and mixed sludge. COD solubilisation and methane potentials from […]
Biologisk denitrifikation av dricksvatten / Biological denitrification of drinking water
A pilot-plant study, made to clarify whether biological denitrification is a possible and suitable method for nitrate reduction of drinking water in Sweden is presented. The concentration of nitrate-nitrogen in un-treated water was 10–15 mg/l. The reactor was a 1.2 m aluminium tube with a inner diameter of 0.19 m. 0.75 m was filled with […]
Teknik för förbättrad kväverening i Sverige – Resultat av landsomfattande enkätundersökning / Methods for improved nitrogen removal in Sweden – results from a questionnaire survey
Käppala wastewater treatment plant (WWTP) in Lidingö, Sweden, treats sewage from 520 000 pe in the north east part of Stockholm. The Käppala association has done an investigation in cooperation with KTH about different methods to improve nitrogen removal. The main techniques in focus were addition of external or internalorganic carbon and separate treatment of […]