Although biological treatment of sewage by activated sludge or trickling filters is widely practiced, these processes still give rise to difficulties. The difficulties may be due to sludge bulking during the activated sludge process or to clogging during the operation of trickling filters. In his studies of biofilters and standard filters, H. Heukelekian (Sewage Works J. 17:23, 516, and 743, 19...

When primary domestic sewage sludge was combined with settled sewage or secondary-treatment plant effluent, synergism resulted. The activity (measured by oxygen uptake, and the removal of Kjeldahl nitrogen and orthophosphate from solution) which resulted from incubating sludge together with settled sewage exceeded the sum of the activities when these components were incubated separately. A simi...

Psychrophilic anaerobic process is an attractive option for sewage treated at moderate and low temperature. The article discusses possibilities of municipal sewage treatment in an upflow anaerobic filter (UAF), operated in the psychrophilic conditions. Investigations were carried out in laboratory scale and the temperature of the bioreactor varied between 1720oC. The investigations comprised tw...

The fate and behavior of estrogenic substances in various biological wastewater treatment processes and several advanced sewage treatment processes were examined. The removal of 17beta-estradiol (E2), estrone (E1) and estriol (E3) was investigated by using a pilot-scale activated sludge plant supplied with domestic sewage. Several sewage treatment plants adopting the activated sludge process we...

Samples collected every two weeks from the inlet and outlet of three sewage treatment plants were screened for the presence of noro-, rota-, astro-, adeno-, hepatitis A- and circoviruses by (RT)-nested PCR, and for F-specific bacteriophages by isolation in Escherichia coli Famp. Plants A and B were secondary treatment plants and plant C used primary treatment. Noroviruses were detected in 43%, ...

Preface The purpose of this publication is to describe on-site technologies for treating domestic sewage where conventional means (public sewer or septic tank with drainfield) are not available. These technologies are described as alternatives in this publication. Our goal is to provide information that can be used by property owners and residents to initiate action to rectify sewage disposal p...

Employees at six sewage treatment plants and three drinking water plants were interviewed for the presence of specific medical symptoms. Serum immunoglobulin concentrations, white blood cell counts and fibrinogen degradation product concentrations (FDP) in urine were determined as were the number and species of airborne Gram negative rods in order to characterise exposure to aerosols of sewage ...

Since water resources of desert Naein City are very limited, a approach which saves water resources and meanwhile meets the needs of the greenspace for water is to use city’s sewage wastewater. Proper treatment of Naein’s sewage up to the standards required for green space uses may solve some of the problems of green space development of the city. The present paper closely examines available st...

sludge production is an avoidable problem arising from the treatment of wastewater. the sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. on the other hand, this sludge has benefits for plants and soils. thereupon, land application of sludge has received...