NITRATE AND PESTICIDES IN GROUNDWATERS IN ANGLIAN WATER, UK
The area served by Anglian Water is one of intensive arable agriculture, leading to many of it’s sources of drinking water exceeding EU Maximum Acceptable Concentrations of nitrate and pesticides before treatment. Concentrations and trends in surface and groundwaters are discussed in the light of recent developments in UK agriculture and legislation. Methods are available […]
DOMESTIC WATER CONSUMPTION IN LATVIA / Hushållsvattenförbrukning i Lettland
In recent years, reconstructing municipal water distribution systems and optimizing their operate conditions have become important tasks in Latvia. Such work requires knowledge of the water balance within water distribution systems to make further decisions. Recorded statistics indicate high domestic water consumption per capita while consumers complain of frequent water shortages at their taps. Different […]
NANOFILTRERING AV HUMUSRIKT YTVATTEN FÖR DRICKSVATTENPRODUKTION / Nanofiltration of surface water rich in humus for drinking water production
Water purification with membrane technology was investigated as one of the alternatives for the rurure drinking water production (6,000 m^/d) in Nynäshamn community. The selected raw water source was surface water from Lake Muskan rather than brackish water from the Baltic Sea. The lake water, without need for desalination, has a high colour number (up […]
FÄRJOR GER FART ÅT ALGER? / Ferry traffic speeds up phytoplankton
Ships, especially huge car-ferries, cause shore erosion and influence the littoral benthic communities along the archipelago routes between Sweden and Finland. Less is known about effects on pelagic communities (phytoplankton). Some effects of ships waves and currents were studied in the Mariehamn ferry harbour area, southern Åland (N. Baltic Sea) in the summer of 1996. […]
MASSBALANSBERÄKNING SOM VERKTYG FOR DRIFTOPTIMERING AV SEDIMENTERING / Mass balance calculations as a tool for optimizing the operation of secondary sedimentation
This paper presents the results of using mass balance calculations for the sludge transport to a secondary sedimentation tank after an activated sludge process with high sludge concentration. An activated sludge process with nitrogen removal often have high sludge concentration and a sludge with sludge settling characteristics. These factors give high sludge load on the […]
MODELLING THE DYNAMICS OF WASTEWATER TREATMENT PROCESSES / Modellering av dynamiska förlopp i vattenreningsprocesser
The main objective of the paper is to briefly describe and exemplify some of the work that has been carried out within the STAMP project at IEA at Lund Institute of Technology within the field of mathematical modeling of wastewater treatment (WWT) processes. Three main areas have been identified – reduced-order models of the activated […]
BIOLOGISK FOSFORAVSKILJNING UNDER LUPPEN / Enhanced biological phosphorus removal under the magnifier
As part of the Swedish research program STAMP (Swedish abbreviation for Control ofWastewater Treatment Plants – Method and Processes) funded by the Swedish National Board for Technical Development, three Ph.D.-students at the Department of Biotechnology, Lund University, have been working with applied research in close collaboration with other University departments and with local full scale […]
NITROGEN REMOVAL IN A SINGLE SLUDGE EBPR PROCESS / Kväveavskiljning i en bio-P process
Studies on enhanced biological phosphorus removal (EBPR) in activated sludge processes have been conducted on a pilot plant at the Sjolunda wastewater treatment plant in Maimo, Sweden, since 1986. The plant receives wastewater from a combined sewer system. The aim of this study was to investigate the consequences of combining EBPR with biological nitrogen removal, […]
PILOT EXPERIMENTS USED FOR DESIGN OF ACTIVATED SLUDGE SYSTEMS – SOME POSSIBILITIES AND PITFALLS / Pilotförsök som grund for dimensionering – nagra fällor och mojiigheter
Two pilot plant set-ups, used to obtain information on a denitrifying non-nitrifying activated sludge system and its usefulness in full-scale, are compared and evaluated. The pilot plant data are used to illustrate effects of simplification of a complex problem in pilot scale. A simple pilot plant supplied with a constant How of wastewater was useful […]
THE EFFECT OF DISSOLVED OXYGEN CONCENTRATION ON THE SETTLING PROPERTIES OF ACTIVATED SLUDGE / Effekten av syrehalt pa sedimenteringsegenkaperna hos aktivt slam
Long-term effects of dissolved (DO) concentration on the settling properties of activated sludge were studied in continuous completely-mixed pilot-plant reactors. Lower DO concentrations (0.5-2.0 mg/1) gave poorer settling properties and higher turbidities of the effluent than higher DO concentrations (2.0-5.0 mg/1). The main reasons to the deteriorated settling properties were excessive growth of filamentous bacteria […]