ÖRESUNDSVERKET- FÖRBEHANDLAT VATTEN / Öresundsverket – Pretreated Waste Water
Through a reconstruction during 1991 Oresundsverker i Helsingborg has been upgraded to a treatmentplant for extensive nitrogen and phosphorus removal. In order to run theese biological processes in the right way, it is important to know what parameters affecting the quality of the pretreated waste water. Furthermore it is important to understand the connection between […]
UTVÄRDERING AV SEDIMENTERINGSFÖRLOPP I AKTIVSLAMPROCESSEN / Evaluation of Sedimentation in Activated Sludge in a Secondary Clarifier
Nitrification and denitrification in activated sludge process will be applied at Kungsängsverket in Uppsala municipality to fulfill future effluent requirements. In order to obtain total nitriflcation, a higher sludge retention time is required than in a conventional activated sludge plant. The highest sludge concentration that can be used is dependent on sludge separation properties and […]
BIOLOGICAL PHOSPHORUS REMOVAL STUDY AT THE SUOMENOJA RESEARCH STATION
Enhanced biologlcal phosphorus removal (EBPR) was studied at the Suomenoja research station in Finland in cooperation with St Petersburg Water and Wastewater Works. The studied process was a mainstream process designed for 10 m3 h-l wkh anaerobic and aerobic units. EBPR proved to be a stable and reliable method that endures organic volumemc loads up […]
CIRCULATION OF PHOSPHORUS IN A SYSTEM WITH BIOLOGICAL P-REMOVAL AND ANAEROBIC SLUDGE DIGESTION / Fosforcirkulation i ett system med biologisk fosforavskiljning och anaerob slamstabilisering
If a high loaded activated sludge process is to be part of a process scheme for nutrient removal anaerobic digestion of the biological sludge has to be considered. However, even when plants are upgraded with a low loaded activated sludge process for nutrient removal anaerobic digestion may be of interest if the energy perspective is […]
KVICKSILVER I GÄDDA – VÄSTERBOTTENS LÄN Kopplingar till omgivningsfaktorer / Mercury in Pike – County of Västerbotten Connections to environmenal factors
This investigation is a result of a cooperation between the County Council, the Municipalities and the County Administration in the County ot Västerbotten, Sweden. The purpose was to study connections between mercury levels in northern pike (Esox Lucius) and environmental factors. Furthermore changes in time were investigated. A classification system, which can be used to […]
TOXINPRODUKTION VID BLOMNING AV BLÅGRÖNA ALGER (CYANOBAKTERIER) / Toxin Production in Blooms of Blue-Green Algae (Cyanobacteria)
The blue-green algal species, Anabaena, Aphanizomenon, Microcystis and Planktothrix, that usually dominates algal blooms, are the same species that produce neuroroxin and/or livertoxin. Furthermore, production of lipopolysacharide endotoxin by blue-green algae has been reported. The ecological significance of blue-green algal toxinproduction is unknown. Protection against phytoplankton consuming zooplankton or chemical warfare (in the competition for […]
ESTIMERING AV ANDELEN PARTIKULÄRT INERT ORGANISKT MATERIAL I AVLOPPSVATTEN / Estimation of the Fraction Unbiodegradable Particulate Organic Material in Wastewater
The goal of this investigation was to determine a value for the fraction of unbiodegradable particulate oganic material in the influent wastewater at the Sjölunda WWTP. The method selected for this purpose was to operate rwo identical laboratory scale units as aerobic fill and draw activated sludge sysrems. This in order to generate data that […]
ÖRESUNDSVERKET – INFLÖDET / Öresundsverket – the Inflow
Ever since the reconstruction of Öresundsverket in Helsingborg was finished in the beginning of 1992 an extensive and regular sampling from the inflow has been carried out. This work has increased the understanding of what variations affecting the outcome of the waste water treatment. The aim of this article is to how how the characterization […]
ANALYS AV DRIFTSTÖRNNGSDATA FRÅN VATTENLEDNINGSNÄT / analysis of Break Data on Water Pipe Systems
This paper presents some of the results of a statistical smdy on reported bursts of water pipes in five swedish cities. The study is a part of a continuing project called PUFF, with the objective to develop guidelines for long-term maintenance and renewal of water and sewer pipe systems. The work was carried out by […]
ALTERNATIVA METODER FÖR ATT LÖSA PROBLEMET MED ROTINTRÄNGNING I AVLOPPSLEDNINGARNA / Alternative Methods to Avoid Operational and Maintenance Problems with Tree Roots in Storm Water and Sewer Pipes
Tree roots entering sewer pipes is an expensive problem which can lead to serious conflicts of interest beween arborist and sewer companies. A substantial amount of money is spent each year on different meaures to remove the roots after they have grown into pipes. The most frequently used methods to prevent root penetration are designed […]