HOBAS GAP-RÖR – FRÅN IDE TILL VÄRLDSPRODUKT / Hobas GRP-pipes – From idea to world product
The paper describes the historical development of Hobas GRP-pipes from one person’s idea about a new design of GRP pipes to a complete new pipe material used world wide. The properties of the new material is briefly described as well as the design and Mr Carlström’s work with the standardisation of GRP pipes
COST EFFICIENT SLUDGE LIQUOR TREATMENT / Kostnadseffektiv behandling av rejektvatten
For sludge liqours the normal way is to lead the different reject water streams back to the inlet of the treatment plant thus producing high and irregular internal loads that can be difficult to control and which cause problems for the normal treatment. A solution to the problem is to introduce a separate treatment. Sludge […]
LUKT OG SMAK AV DRIKKEVANN – KAN VI IDENTIFISERE PROBLEMKOMPONENTENE? / Drinking water off-flavours – can we identify their chemical constituents?
Odour and taste problems are among the most common reasons for consumer complaints to drinking water quality. This work describes extraction and quantification of volatile organic components (VOC) in water, including well-known odour components and disinfection byproducts. The analytical approach is based on purge and trap of VOC from drinking water at various experimental conditions […]
PHOSPHORUS MANAGEMENT AND SOCIETAL STRUCTURE Hampered effluent accumulation processes (HEAP) in different areas of the Swedish society / Fosforhantering och samhällsstruktur Ackumulationseffekter i det svenska samhället
Some of the problems of phosphorus pollution and source exhaustion are identified to be time-dependent, structural problems. This is demonstrated to be the case in land independent animal production, in urban settlements and in the waste-water treatment – landfill cycle. A calculation indicates that saturation of the systems can take place in the time range […]
LÅNGSAMFILTRERING – EN ENKÄTUNDERSÖKNING AV SVENSKA FILTER Slow Sand Filtration – an Investigation of Swedish Slow Sand Filters
At present there is an increasing interest in rhe reduction of natural organic matter, NOM, from drinking water by biological processes instead of chemical processes. In Europe as well as in the US a lot of research is done to increase the knowledge of biological processes in slow sand filters. Removal of organic matter in […]
FEM-ANALYS AV STRÖMNINGSFÖRHÅLLANDENA I EN DAGVATTENDAMM / FEM-analysis of the hydraulic conditions in a stormwater detention pond
In 1996 Goteborg Water and Sewage Works built a stormwater detention pond, with a catchment area consisting of a city highway and a domestic area. Models of the pond in two and three dimensions were made with a finite element program, FIDAP. The hydraulic conditions have been simulated for different flow intensities. Particle removal, as […]
UPPGRADERING AV SLAMAVSKILJARE GENOM TILLBYGGNAD AV BIOLOGISKA BEHANDLINGSSTEG / Upgrading of small wastewater treatment plants by using biological treatment
The Municipality of Skelleftea is responsible for the operation of several small wastewater treatment plants with insufficient removal of organic matter and nutrients. The small wastewater treatment plants normally consist of septic tanks. A common solution to improve the removal efficiency of small plants is to build infiltration beds. However, due to local conditions this […]
UTVECKLINGEN INOM VATTENPLANERINGSOMRÅDET / The development in planning of water resources
The work with water resources has changed during the last two-three decades. We have solved the problems with point sources. Now we have to concentrate on the diffuse sources, within a sector integrated planning EU is working on a Framework Directive for water, with demands of river basin management. The use of water resources depends […]
AN APPROACH TO USING THE DEGREE DAY METHOD FOR URBAN SNOW DEPOSIT MELT / Graddagarsmetoden för beräkning av smältning av snötippar
Snow melt and snow handling are of great concern for the municipalities in cold regions. Urban run off is influenced by the piling of snow. In order to design deposit areas, storm water systems, etc. forecasts of urban snow melt run off should consider melting of snow piles. Piling of snow delays the melt and […]
AN ALTERNATIVE ROAD CONSTRUCTION FOR STORMWATER INFILTRATION IN A COLD CLIMATE / Alternativ gatukonstruktion för dagvatteninfiltration i kallt klimat
By using an alternative road construction with permeable asphalt over an open-graded aggregate base the stormwater is infiltrated into the ground. No regular stormwater pipes and manholes are needed A full scale study of an alternative road construction in a cold climate is presented in this article. Two roads in a housing area in Luleå, […]