HYDROLOGISK OCH HYDROKEMISK MODELLBERÄKNING I SJÖRIKA SKOGSOMRÅDEN / Hydrological and hydrochemical simulation in basins dominated by forests and lakes
A hydrological model for runoff simulation in basins dominated by forests and lakes has been developed and tested. The results suggest that the dynamics in the runoff record may be reproduced without extensive model calibration provided the damping in the lakes is described explicitly and a division into submodels is made. The volume errors may […]
THE DISSOLUTION EFFICIENCY FOR DIFFERENT STREAM LIMING METHODS AND TECHNOLOGIES
The dissolution efficiency for different stream liming methods can be shown to depend upon a small number of parameters. They are several orders of magnitude more important than other parameters influencing the dissolution efficiency. The parameters are: – Particle size distribution – Initial pH-value– Dose intensity– Degree of wet slurrying The particle size distribution and […]
EFFEKTER AV SMÅBÅTSHAMNAR PÅ DJURLIVET I GRUNDA HAVSOMRÅDEN PÅ SVENSKA VÄSTKUSTEN, / Effects of Small Boat Harbours on the Fauna in Shallow Marine Areas on the West Coast of Sweden
On the Swedish west coast an increased demand for new small boat harbours has often lead to conflicts with the coastal fishery and nature conservationists. In this study the effects of small boat harbours on the mobile epibenthic fauna (shrimps, crabs and small fishes) and infauna (mussels, worms and small crustaceans) were investigated. Quantitative samples […]
TILLFÖRSEL AV PETROGENA KOLVÄTEN (PHC) TILL SALTSJÖN OCH ÖSTRA MÄLAREN I STOCKHOLMS LÄN – EN ÖVERSIKTLIG UPPSKATTNING AV KÄLLOR OCH MÄNGDER / The Input of Petroleum Hydrocarbons(PHC) to Saltsjön and Eastern Mälaren in the Province of Stockholm – An Approximate Estimation of Sources and Quantities
The input of petroleum hydrocarbons (PHC) to the coastal waters in the province of Stockholm has been theoretically estimated to 150-630 tons/year. The main quantity originates from land-based discharges. These are transported to the coastal waters directly from municipal waste water treatment plants (20-60 tons/year) and industries (40-145 tons /year) and indirectly from atmospheric fallout […]
STORM OVERFLOWS IN NORWAY- POLICIES AND PRESENT SITUATION
Storm overflows contribute considerably to pollution. However, the pollution authorities and municipalities often fail to take appropriate measures to correct the situation. Investigations in Norway have shown that the storm overflow constructions and maintenance usually are not satisfactory. On the other hand, research projects have shown that storm overflow types, like the swirl concentrator, perform […]
APPLICATION OF ION EXCHANGE AS BIOFILTER FOR COMPLETE RECIRCULATlON IN AQUACULTURE
A recently developed system for recirculation of aquaculture waste water was examinined. It is based upon the use of settling, a mixture of 3 ion exchangers, and sand filtration. The results were satisfactory, giving an acceptable water quality over a period of 7 months with complete recirculation. The ion exchange unit is also operating as […]
MUTAGENIC ACTIVITY IN DRINKING WATER AND HUMIC WATER AFTER CHLORINE TREATMENT
Mutagenic activity in Salmonella typhimurium strains TA100 and TA98 was determined for chlorinated drinking water, purified from raw water with a high content of humic material, and for a natural humic water treated with chlorine. A remarkably high activity was found for XAD-4/8 concentrates of acid water samples compared to neutral samples in tests performed […]
FULLSKALEFÖRSÖK MED NITRIFIERING AV REJEKTVATTEN FRÅN CENTRIFUGERING AV RÖTSLAM VID BROMMA AVLOPPSVERK / Full-Scale Experiments of Nitrification of Sidestreams from Centrifugation of Digested Sludge at Bromma Municipal Wastewater Treatment Plant
Bromma municipal wastewater treatment plant is the second largest plant in Stockholm with a design flow of 160,000 m3/day. Decisions were made in 1982 to study nitrification of side- streams from the dewatering of digested sludge in full-scale at Bromma in order to improve the overall nitrification capacity of the plant. The investigation is jointly […]
THE CONTINUOUS ON-LINE MONITORING OF ENVIRONMENTAL POLLUTANTS IN STORMWATER
A monitoring system is described which provides continuous measurements of selected pollutants in stormwater. The system, which has been installed at both the outfall to a storm-water pipe system and in a gullypot, is sensitive to changes in pH, conductivity, dissolved oxygen concentration, temperature and redox potential. At the stormwater outfall monitoring station rapid changes […]
FRAMTAGNING AV ETT DATORBASERAT REGLER- OCH INFORMATIONSSYSTEM FÖR CENTRIFUGPROCESSEN VID SICKLA SLAMBEHANDLINGSANLÄGGNING I STOCKHOLM / A Computer Based System for the Centrifuge Process in Sewage Treatment
It has been more and more common to use centrifuges for the removal of sludge during sewage processing. The centrifuge process is relatively complex and requires valuable polymers to be effective. In addition reject water is re-introduced for re-purification which usually entails an inordinate extra load on the sewage plant, particularly during periods of high […]