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...

Wastewater treatment is necessary to reduce the health risks and environmental impacts associated with discharge of untreated wastewater. The most common way to treat wastewater in wastewater treatment plants is through the activated sludge process. Although the main principle of the process has been the same since its usage began 100 years ago, there has been a continuous development and moder...

Membrane Bioreactor (MBR) process consists of a biological reactor integrated with membranes that combine clarification and filtration of an activated sludge process into a simplified, single step process. The membrane is an absolute barrier to suspended matter and microorganisms and it offers the possibility of operating the system at high mixed liquor suspended solids (MLSS) concentration. Th...

background: conventional wastewater treatment is a combination of physical and biological processes designed to remove organic matter from solution. waste sludge drawn from these processes is thickened and processed for ultimate disposal wastewater contains various kinds of infectious agents, such as bacteria, viruses, fungi and parasites. correct treatment in wastewater treatment plants is imp...

this research was done in order to determine the basic criteria for “tehran oil refinery effluemt treatmentunit” to prove the feasibility of the application of powdered activated carbon in aeration zone of activated sludge system. the main stages of this research included: determination of qualitative and quantitative characteristics of raw wastewater preparation of two pilot scale units of act...

This paper presents a very useful software tool to design, simulate and optimise wastewater treatment plants. The program is called DESASS (DEsign and Simulation of Activated Sludge Systems) and has been developed by CALAGUA research group. The mathematical model implemented is the Biological Nutrient Removal Model No.1 (BNRM1) which allows simulating the most important physical, chemical and b...

The feasibility of treating municipal wastewater by a combined ozone-activated sludge continuous flow system was studied. Lab-scale experiments of both single activated sludge and combined ozone-activated sludge processes were carried out to determine the kinetic coefficients of the biological stage. The results obtained indicated a clear improvement in the kinetic parameters of the aerobic oxi...

Limited available water resources have rendered wastewater reuse an important issue to specialists in most developed countries, today. The current study works on membrane filtration for treatment of industrial wastewater. By comparing the two methods of membrane bioreactor (MBR) and hybrid membrane electro bioreactor (MEBR) processes, it finds that earlier fouling in the membrane occurs in the ...

Activated sludge is widely used to treat municipal and industrial wastewater globally and the formation of activated sludge flocculates (flocs) underpins the ability to separate sludge from treated water. Despite the importance of activated sludge flocs to human civilization there have been precious few attempts to rationally design fit for purpose flocs using a bottom-up approach based on a so...