introduction: the presence of pathogenic microbial agents and pathogens in organic fertilizers causes health problems and disease transmission. the aim of this study was to evaluate the efficiency of vermicomposting process in improve the microbial quality of the compost produced. methods: this experimental study was conducted as a pilot-scale one, in the laboratory of school of health. in orde...

reaction constants and heat release during thermophilic aerobic digestion of typical secondary and mixed sludges were determined. maximum reaction constant, determined by measuring the amounts of biodegradable volatile suspended solids (bvss) removed, occurred in the temperature range of 55-60 ºc. measurement of heat releases were carried out, at the same range, by the aid of a temperature prog...

Anaerobic digestibility of the waste activated sludge (WAS) discharged from large-scale membrane bioreactors (MBRs) and conventional activated sludge processes (CASs) were compared using batch trials. Four wastewater treatment plants were sampled. Results showed that the sludge from MBRs had poor anaerobic digestibility as it had lower volatile solid (VS) reduction rate and lower maximum biogas...

Lightweight aggregate (LWA) production with sewage sludge and municipal solid waste incineration (MSWI) fly ash is an effective approach for waste disposal. This study investigated the stability of heavy metals in LWA made from sewage sludge and MSWI fly ash. Leaching tests were conducted to find out the effects of MSWI fly ash/sewage sludge (MSWI FA/SS) ratio, sintering temperature and sinteri...

Principles of aerobic and anaerobic treatment of organic wastes were developed in the previous papers of this symposium. The application of these principles to engineering design is discussed in this paper. Although the discussion is restricted to the aerobic treatments, the concepts are equally applicable to anaerobic treatments. Laboratory or pilot plant studies are employed to develop engine...

A one year study was carried out in a waste stabilization ponds system where septage and sewage are cotreated. The system consists of two septage ponds which operate alternately followed by two ponds in series which receive the combined effluent. The septage ponds also act as evaporation ponds for the accumulated sludge. The monitoring program was divided in two phases. The results of the first...

Wool scouring sludge is the solid waste product of anaerobic treatment of wool scouring effluent. It has a high wool grease content (1316% of the dry weight, 45 -55% of the organic matter), resulting in a low melting point (approx. 45°C). The low melting point, the putty-like physical properties and the odourous. unstable nature of the sludge makes it unsuitable for land application in its raw ...

Ultrawaves sludge sonication technology was trialled at Maroochydore STP from February to June 2013. This was believed to be the first fullscale application of mechanical sludge lysis for enhanced denitrification in Australia. The results of the trial confirmed that sonicated waste activated sludge (WAS) could effectively replace the use of methanol as a carbon source for denitrification, and t...

In this study duckweed (Lemna gibba) and waste activated sludge (WAS) were co-digested in different proportions with acclimatized anaerobic granular sludge (AAGS) in mesophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of waste activated sludge alone. Results indicate that co-digestion with both duck...

Modelling solar drying rate of waste-water sludge Ido Seginer* and Markus Bux 1 Civil and Environmental Engineering, Technion, Haifa, Israel 2 Agricultural Engineering, University of Hohenheim, Germany *Corresponding author. Fax: 972 4 829 5696; E-mail: [email protected] Efficient solar drying requires that the drying rate is quantitatively known as a function of the environment and th...