PROCESSES THAT DETERMINE THE pH OF SEAWATER
The pH of seawater is dependent on shifts in the autoprolysis of hydrogen carbonate 2 HCO3-= CO2 + H2O + CO32-caused by the production and decomposition of planktonic maiter. Using stoichiometric relationships and mean concentrations of nitrate and phosphate it is shown that surface seawater will have a pH close to 8 at 15°C on […]
UDBYGNING – BLA VED RENSNING AF REJEKTVANDET – AF FREDERIKSHAVN KOMMUNES CENTRALRENSEANLÆG / Extension – Including Reject Water Treatment – of the Municipal Sewage Treatment Plant of Frederikshavn
In June 1990 the Municipality of Frederikshavn inaugurated the world’s first full-scale plant for chemical-physical treatment of the reject water. After a working period of more than a year with adjustments and corrections the plant is working very satisfactorily, and together with the planned installation of the French developed BIOSTYR system the reject water treatment […]
PILOTSKALEFÖRSÖK MED NITRIFIERING AV REJEKTVATTEN MED SBR-TEKNIK PÅ BROMMA RENINGSVERK / Pilot Plant Scale Investigations of Nitrification of Sidestreams with SBR Technology at Bromma Sewage Treatment Plant
A pilot plant scale investigation of nitrification of sidestreams from centrifugation of digested sludge was carried out at Bromma sewage treatment plant in the beginning of 1991. The SBR technology (Sequencing Batch Reactor technology) was implemented. The investigations, which have been carried out, showed that the SBR technology is appropriate for nitrification of sidestreams. Complete […]
VAD ÄR EGENTLIGEN DENITRIFIKATION OCH HUR MÄTS DEN? / What is Denitrification and How is it Measured?
Denitrification involves the bacteria-mediated reduction of nitrate, nitrite and nitrous oxide to atmospheric dinitrogen. The evolved nitrogen gas usually leaves the environment in which it was produced and diffuses to the atmosphere. The process appears in most environments where decomposable organic matter has accumulated, e.g. soils, lake sediments and wetlands. Through the decomposition of organic […]
TEKNISKA MÖJLIGHETER ATT FÖRBÄTTRA VÅRA VA-SYSTEM / Technical Possibilities to Improve Our Water Supply and Sewerage Systems
The paper describes the technical improvements which can be effected in our existing water supply and sewerage networks in order to secure the present function demands regarding public health and environment. A substantial development work has been accomplished in this field during the later years and ongoing R&D projects are described. At present there are […]
GNESTA VATTENFÖRSÖRJNING – SAMSPEL MED NATUREN FÖR GODARE VATTEN / Gnesta Water Treatment – a Process Intergrated with Nature for Higher Quality
Upgrading existing water treatment plants includes evaluating possibilities lo get a new raw water source. Both quality and quantity can be increased. The natural resources should be regarded as possible stages in a process. It requires a coordination of knowledges in geohydrology and water process engineering. Upgrading Gnesta Water Treatment Plant is a good example […]
KVÄVEUTSLÄPP VID TUNNELDRIFT FÖR JÄRNVÄG I BOTKYRKA KOMMUN / Nitrogen Emission by Tunnelwork for Railway in Botkyrka Parish, Sweden
Tunnelwork for the new railway through Botkyrka parish has shown to generate a large nitrogen emission to water recipients. Tot-N concentrations over 50,000 ìg/l have been measured in water from the tunnel outlet. The maximum amount of nitrogen emitted to water recipients as NH3, NO2 and NO3 from a tunnellength of approx 4.8 km is […]
KVÄVEREDUKTION VID ÖVERSILNING / Nitrogen Reduction on Inundated Meadows
Inundation of meadows is an old farming system, where the water from a river is used to flood the nearby meadows during a number of days, in order to increase the production. During 1991 it has been tested, in two places in Scania (the southernmost part of Sweden), as a system for removing nitrogen from […]
OM NITRIFIERANDE BAKTERIER / On the Role of Nitrifying Bacteria
The composition of the nitrifying microflora may vary considerably between different sewage treatment plants. The taxonomy of the nitrifying bacteria and the conditions needed for nitrification are outlined. Present and future methods for the detection of nitrifiers and the assessment of nitrification inhibition are discussed.
KOMBINERAD BIOLOGISK FOSFOR- OCH KVÄVEAVSKILJNING STUDIER I PILOTSKALA / Combined Biological Phosphorus and Nitrogen Removal. Pilot Plant Studies
Combined biological phosphorus and nitrogen removal is being studied in a cooperative project involving the Department of Water and Environmental Engineering at Lund Institute of Technology and Sjölunda sewage treatment plant in Malmö. The project aims at finding out the lowest effluent concentrations of phosphorus and nitrogen that can be obtained in a combined process. […]