The variation of moisture during sewage sludge bio-drying was investigated. In situ measurements were conducted to monitor the bulk moisture and water vapor, while the moisture content, water generation, water evaporation and aeration water input of the bio-drying bulk were calculated based on the water mass balance. The moisture in the sewage sludge bio-drying material decreased from 66% to 54...

The Commission of the European Communities (CEC) is just working out a new directive in order to regulate the agricultural reuse of sewage sludge. This new regulation will also effect a “special case” – sludge usage in a mountainous environment – which will be discussed in this paper. Three reuse sites at small wastewater treatment plants of mountain refuges at altitudes more than 2,000 m a.s.l...

The up flow anaerobic sludge bed (UASB)-digester system is one promising low temperature anaerobic process for sewage treatment. In this study, the effects of height of UASB sludge transfer (HUST) on performance of a UASB-digester system treating sewage at 15°C were studied. The studied HUSTs were 27, 47 and 67 cm in the UASB sludge bed of 70 cm, from which sludge was transferred to the digeste...

More stringent controls on the quality of wastewater discharges have given rise to increasing volumes of sewage sludge for disposal, principally to land, using either land-spreading or sludge-to-landfill operations. Current sludge-to-landfill methods generally involve mixing the concentrated sludge with other solid waste in municipal landfills. However, stricter waste disposal legislation and h...

Deterministic and probabilistic risk assessments were developed for commercial LAS in agricultural soil amended with sewage sludge. The procedure done according to ILSI Europe's Conceptual Framework [Schowanek, D., Carr, R., David, H., Douben, P., Hall, J., Kirchmann, H., Patria, L., Sequi, P., Smith, S., Webb, S.F., 2004. A risk-based methodology for deriving quality standards for organic cont...

The aim of this research study was to analyse the effect of applying inverted phase fermentation (IPF) prior to the anaerobic digestion of cattle manure and sewage sludge. IPF promotes the endogenous bacteria present in waste and hence enzymatic hydrolysis, producing a solid-liquid separation. The clarified bottom layer or liquid phase (LP, 70% volume in manure and 65% in sludge), and the thick...

A method in which the polymerase chain reaction (PCR) was used was developed to amplify either a uidA gene fragment or a 16S rRNA gene fragment from Escherichia coli in sewage and sludge. Because of interference caused by humic acidlike substances, crude DNA extracts were purified with a Sephadex G-200 spun column before the PCR was begun. A Southern analysis in which a nonradioactive chemilumi...

A transgenic strain of the model nematode Caenorhabditis elegans in which bioluminescence reports on relative, whole-organism ATP levels was used to test an environmentally-relevant mixture of pollutants extracted from processed sewage sludge. Changes in bioluminescence, following exposure to sewage sludge extract, were used to assess relative ATP levels and overall metabolic health. Reproducti...