aims: intensification of current environmental legislation leads to an increase wastewater treatment sludge volume. so reducing the sludge volume is considered as a strategy to improve and solve the problems of secondary pollution of sludge. dissolved air flotation (daf) as a substitute clarifier is used for separation of activated sludge liquid-solid phases. the aim of this study was to estima...

osa (oxic settling anoxic) process is one of the sludge reduction methods. in this method an anaerobic reactor is placed in activated sludge recycling line for sludge reduction purpose. this method is getting popular because of possibility of its application in currently operating waste water treatment plants. in this research, the performance of osa process in sludge reduction in sbr was impro...

Organic fraction of solid waste, which upon degradation produces foul smell and generates pathogens, if not properly managed. Composting is not a method of waste disposal but it is a method of waste recycling and used for agricultural purposes. An integrated approach of composting methodology was tested for municipal solid waste management. Solid waste first was composted and after 22 days, was...

organic fraction of solid waste, which upon degradation produces foul smell and generates pathogens, if not properly managed. composting is not a method of waste disposal but it is a method of waste recycling and used for agricultural purposes. an integrated approach of composting methodology was tested for municipal solid waste management. solid waste first was composted and after 22 days, was...

The Combined Activated Sludge-Anaerobic Digestion Model (CASADM) quantifies the effects of recycling anaerobic-digester (AD) sludge on the performance of a hybrid activated sludge (AS)-AD system. The model includes nitrification, denitrification, hydrolysis, fermentation, methanogenesis, and production/utilization of soluble microbial products and extracellular polymeric substances (EPS). A CAS...

Excess wastewater sludge collected from the recycling stream of an activated sludge process is biomass that contains large quantities of polysaccharides and proteins. However, relevant literature indicates that the bio-conversion of wastewater sludge to hydrogen is limited and therefore not economically feasible. This work examined the anaerobic digestion of wastewater sludge using a clostridiu...

This paper presents the results of an investigation on the effects of concentration of cations on activated sludge properties and membrane fouling in submerge membrane bioreactors. The working volume of the experimental setup was two liters. The cellulose acetate membrane was immersed in the bioreactor. The flocculability, settling properties and fouling propensity of activated sludge was measu...

In biological wastewater treatment technologies the majority of systems are based on activated sludge technology. In these systems the population structure and dynamics of the activated sludge microbial community is largely governed by indirect regulatory mechanisms, such as aerated/nonaerated reactors, reactor configurations and sludge recycling ratios. The build-up of activated sludge flocs (...