An experimental methodology was developed to improve the energy design of paddle dryers for sewage sludges. A laboratory batch dryer with a vertical agitator has been especially designed and instrumented to determine the heat flux densities. To determine the drying kinetic and the evaporating flow rates, the specific heat and the total heat of desorption of the sludge were measured using calori...

Sludge from sewage treatment plants (STPs) is recognized as a sink of moderate to high lipophilic compounds resistant biodegradation. Herein, we investigate the presence emerging pollutants in sludge combining information provided by mass spectrometry detection, following ultra-performance liquid chromatography (UPLC), with use an accurate spectral database pesticides and pharmaceuticals. In fi...

• End-products of sludge-based AD were used for SCP production the first time. A potential solution to valorize underutilized products generated at WWTPs. Methylomonas dominated in mixed culture. The protein content reached 41% w/w dry weight. Several essential amino acids detected. Single cell (SCP) provides an alternative source partially replace conventional agricultural resources and suppor...

Solar dried sewage sludge (SS) conversion by pyrolysis and gasification processes has been performed, separately, using two laboratory-scale reactors, a fixed-bed pyrolyzer and a downdraft gasifier, to produce mainly hydrogen-rich syngas. Prior to SS conversion, solar drying has been conducted in order to reduce moisture content (up to 10%). SS characterization reveals that these biosolids coul...

This paper presents results of a plot-scale field experiment aiming at the comparative evaluation of agricultural practices and agricultural systems as far as their performance in very-low-rainfall conditions is concerned. Wheat was seeded after common vetch, treated in three different ways, after fallow or after the incorporation of dried sewage sludge or straw. Grain and straw yields and grai...

The article presents research results on obtaining phosphorus granulated fertilizers on the basis of microbiologically activated sewage sludge ashes, ground bones and dried blood from meat industry. Granulation tests were carried out using a laboratory pan granulator as well as on an experimental pilot plant. The aim of the studies was to select the proper composition of the mixture of raw mate...

Alternate cycling of sludge in aerobic, anoxic, and anaerobic regimes is a promising strategy that can reduce the sludge yield of conventional activated sludge (CAS) by up to 50% with potentially lower capital and operating cost than physical- and/or chemical-based sludge minimisation techniques. The mechanisms responsible for reducing sludge yield include alterations to cellular metabolism and...

The literature on reduction of excess sludge production by ozonation is summarized. Two sequencing batch reactor experiments where sludge is ozonated for this purpose are performed. The purpose of these is to evaluate the prospects of using ozonation to reduce excess sludge production in two different kinds of sludge. Urban sewage sludge is used in the first, and paper mill sludge in the second...