FÖRSÖK MED MIKROSAND SOM FLOCKHJÄLPMEDEL VID RINGSJÖVERKET / Tests with Microsand as a Coagulant Aid at the Ringsjö Plant
At the Ringsjö plant, laboratory and pilot scale tests has been carried out with a process for water treatment where the conventional process coagulation-flocculation-sedimentation is accelerated by dosing of microsand in the flocculation step. The microsand improves the sedimentation velocity of the flocs formed, while at the same time reducing the flocculation time needed. The […]
PINPOINTING AND DETERMINATION OF PYRANINE 120 % COLORANT IN LEAK WATER
The Pyranine 120 % colourant is chemically the sodium salt of 3-oxypyrenetrisulphonic acid. It is used to colour district heating water when seaking leaks into warm domestic water supplies. It colours the water a fluorescent yellowish green, and small amounts can be detected either by UV light or spectrophotometrically. It is not detrimental to health.
INACTIVATION OF BACTERIA WITH SMAC – A STABLE SOLUTION OF CHLORINE DIOXIDE IN WATER
Chlorine dioxide is a highly effective oxidising agent with powerful deodorising and bleaching properties. Its action on pathogenic micro-organisms is stronger than that of chlorine. A major drawback has, until now, been that chlorine dioxide invariably must be produced on the spot by reacting chlorine or hydrochloric acid in solution with sodium chlorite. A stable […]
PROBLEM OCH RISKER VID ANVÄNDNING AV SLAM I JORDBRUKET / Problems and Risks in Agricultural Sludge Use
Sewage sludge is in most cases not accepted as a fertilizer in agriculture. The reason is a concern for eventual environmental effects due to the presence of environmentally hazardous substances in sludge. Use of sludge in agriculture will not lead to environmental effects. A risk analysis shows this. Consequently, there are no environmentally hazardous substances […]
REJEKTVATTENBEHANDLING MED OMVÄND OSMOS / Reject Water Treatment with Reverse Osmosis
In water with high levels of nitrogen, it can be of interest to use reverse osmosis for removal of the nitrogen. This can help to reduce the total load of the wastewater treatment plant. To improve removal of nitrogen, high pressure can be used to press the nitrogen-water through a reverse osmosis membrane. The nitrogen […]
INVERKAN AV SYRE- OCH SLAMHALTEN PÅ NITRIFIKATIONSHASTIGHETEN / Influence of the Oxygen and Mixed Liquor Suspended Solids Concentration on the Nitrification Rate
Experiments were carried out at Bromma wastewater treatment plant with nitrification of reject water using SBR technics (Sequencing Batch Reactor). The studies were performed mainly in a pilot plant scale, but some complementary tests were done in a laboratory scale. The purpose was to give a basis for estimation of an appropriate oxygen concentration and […]
INTEGRATION OF ON-LINE INSTRUMENTS IN THE PRACTICAL OPERATION OF THE KLAGSHAMN WASTEWATER TREATMENT PLANT
The Klagshamn wastewater treatment plant is operated with extended BOD, phosphorus and nitrogen removal. A high and stable removal of nitrogen is reached with a process configuration based on pre-precipitation and the use of an external carbon source in a single sludge post-denitrification process. The detention time in the bioreactor is about 7 hours. The […]
EXPERIMENTS AND RUNNING RESULTS OF THE START UP OF THE PRIMARY DIGISTER IN ’CZAJKA’ SEWAGE TREATMENT PLANT IN WARSAW
The Warsaw WWTP ”Czajka” was designed for the flow of 400000 m3/d. During wastewater treatment 4 800 m3 /d sludge settle down in the primary settling tanks. It’s a mixture of primary and excess activated sludge. The settling tanks are desludged three times a day and the sludge flows by gravity to 4 thickener and […]
NY TEKNIK FÖR SMÅSKALIG AVLOPPSRENING / A New Technique to Operate SBR Package Plants
This paper describes a new technique to operate SBR package plants. The whole process – aeration, integral liquid flow, excess sludge withdrawal and addition of precipitation chemicals – is powered by a single side channel blower. The conclusion is that the gain of this technique are package plants extremely low in service and maintenance.
ÅTGÄRDER MOT UTSLÄPP AV LUFTFÖRORENINGAR I EUROPA / The International Acid Rain Problem from a Swedish Perspective
Between 80 and 90 per cent of the deposition of acidifying air pollutants on Sweden originates in other countries. Most of it comes from western Europe, with Germany and Great Britain being the two biggest contributors. In the 1980s, European emissions of sulphur dioxide decreased by 25-30 per cent, while those of nitrogen oxides increased […]