INTERMITTENTA BEHANDLINGSMETODER INOM AVLOPPSVATTENRENING, SÄRSKILT SBR-TEKNIK / Intermittent Methods for Sewage Treatment, Specially SBR-Technique
This paper introduces different intermittent biological treatment methods of waste water to the Swedish public. Intermittent methods are widespread internationally, but seldom used in Sweden. The following methods are presented: – the Intermittent Cycle Extended Aeration process (ICEAS) – the phased isolation ditch process, namely the ”biodenitrosystem” – the Sequencing Batch Reactor process (SBR). The […]
LÅNGSAMFILTRERING / Slow Filtration
Production of drinking water by slow filtration is an old method getting new aspect nowadays. Filtration mechanism is on principle the same as in other granular filters. Dispersed matter is destabilized by biochemical activity of microorganisms. Separated organics retained in the filter for several months/years are degradated by aerobic digestion instead of being removed by […]
NITRAT I GRUNDVATTEN / Nitrate in Ground Water
Reverse osmosis was found to reduce >90 % of the nitrate content in ground water from two different wells. Alternatives like ion exchange (e.g. CARIX) were found in literature.
MIXING SURFACE WATER AND GROUNDWATER IN A SMALL NORWEGIAN WATERWORK. INFLUENCE ON WATER QUALITY AND CORROSION IN THE DISTRIBUTION SYSTEM
Asketjern/Blaker waterwork (ca. 5,500 persons) was until 1985 supplied with acid, soft surface water with a high humus concentration. The distribution system consists mainly of asbestos cement and cast iron pipes, and severe corrosion occurred. pH near 11 was measured at end points of asbestos cement pipes. There was no treatment for corrosion control. From […]
HALOCARBON CONCENTRATIONS IN ASKERÖFJORDEN RELATED TO THE WATER EXCHANGE AND INPUTS FROM THE PETROCHEMICAL SITE AT STENUNGSUND
The concentrations of chloroform, carbon tetrachloride, dibromochloromethane, bromoform, methyl chloroform and perchloroethylene have been determined at 13 stations in the area of the petrochemical centre at Stenungsund. The concentrations of methyl chloroform and perchloroethylene confirm a water exchange of Askeröfjorden of 5-15 % per day. Large variations of the halocarbon concentrations at depths of 1 […]
AVLOPPSRENING ELLER RESURSANVÄNDNING? / Wastewater Treatment or Resource Management?
Swedish environmental policies have aimed at connecting even small point source discharges to tertiary treatment plants, either by large scale collection and treatment systems or by small separate plants. The cost-effectiveness of the strategy for a number of urban areas with less than 1,000 inhabitants was evaluated in one municipality (115,000 inhabitants) in the south […]
RÖNNINGESJÖNS TILLFRISKNANDE. RESULTAT EFTER DAG- OCH SJÖVATTENBEHANDLING ÅREN 1981-1987 / Recovery of the Lake Rönningesjön in Täby, Sweden. Results of Storm and Lake Water Treatment over the Years 1981-1987
A fullscale plant applicating the Karl Dunkers’ system for combined treatment of separate storm water and lake water is since 1981 operating in the northern part of the lake Rönningesjön, close to Stockholm. The treatment is executed in three simultaneous steps: 1) flow balancing in tanks floating in the lake, 2) phosphorus removal using Fe […]
RECIPIENTBALANS SÖRMLAND – EN MODELL FÖR BERÄKNING AV FOSFORTRANSPORT I DE SÖRMLÄNDSKA VATTENDRAGEN / A Model for Calculating Phosphorus Transport in the Watercourses of the County of Södermanland, Sweden
The addition of plant nutrients to the sea is today one of the most important environmental problems. It is of the outmost importance that measures taken against such discharges will be as cost effective as possible. A computer based mathematical model is described to calculate the transport of phosphorus to the recipient. The drainage area […]
BERÄKNING AV AVRINNING OCH KVÄVELÄCKAGE FRÅN ETT VATTENDRAG MED OLIKA MARKANVÄNDNING / Modelling of Runoff and Nitrogen Leaching from a Basin with Different Land Use
A conceptual model for simultaneous computation of runoff and inorganic leaching from forests, arable lands and lakes has been developed and tested. The model has been verified against data from the Ekenäs area in the county of Södermanland in SE Sweden. The aim is to develop a model which includes the most important factors controlling […]
ET EKSEMPEL PÅ INTERNATIONALT SAMARBEJDE OM AT BEGRÆNSE TILFØRSLEN AF NÆRINGSSALTE FRA LANDBRUG TIL ØSTERSØOMRÅDET / International Cooperation in Reducing the Discharge of Nutrients from Agriculture to the Baltic Sea Area – An Example
Eutrophication is one of the serious pollution problems in the Baltic Sea Area. The nutrients originate from different sources. Agriculture is one of the important sources. In 1985 The Helsinki Commission decided to establish an agriculture working group. The aim of the group was to draft recommendations on reduction in agricultural pollution. The working group […]