active filters have proven to be more effective than passive techniques to improve power quality and to solve harmonic and power factor problems due to nonlinear loads. this paper proposes a control scheme based on the instantaneous active and reactive power. the inverter of this active filter is a three-phase, two-level converter. space vector technique is used as modulators and pattern genera...

A non-isolated DC/DC converter with high transfer gain is proposed in this paper. The presented converter consists of the switched inductor and three-level converters. The DC/DC power converter is three-level boost converter to convert the output voltage of the DC source into two voltage sources. The main advantages of DC/DC converter are using low voltage semiconductors and high gain voltage. ...

Large volumes of sludge are produced from onsite sanitation systems in densely populated areas (e.g. slums and emergency settlements) and wastewater treatment facilities that contain high amounts of pathogens. There is a need for technological options which can effectively treat the rapidly accumulating sludge under these conditions. This study explored a pilot-scale microwave (MW) based reacto...

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...

A membrane bioreactor (MBR) and an activated sludge process (ASP) were operated side by side to evaluate the change of sludge supernatant characteristics and the evolution of the sludge fouling propensity. The MBR sludge had a higher organic concentration and more biopolymer clusters (BPC) in the supernatant compared with ASP. BPC increased in both concentration and size in the MBR. The results...

High-rate anaerobic digestion can be applied in upflow anaerobic sludge blanket reactors for the treatment of various wastewaters. In upflow anaerobic sludge blanket reactors, sludge retention time is increased by a natural immobilization mechanism (viz. the formation of a granular type of sludge). When this sludge is cultivated on acid-containing wastewater, the granules mainly consist of an a...

This study combines a two-phase biological treatment system of activated sludge/contact aeration process by adding biological contact filters into the rear sector of the activated sludge aeration tank of the slaughterhouse wastewater treatment plant. This system keeps the advantages of complete mixing of substrates and microorganisms and flexible operation of the activated sludge process, and i...

In the processes of wastewater treatment, significant amounts of iron phosphate containing sludge is discharged. One of the recycling methods of this sludge, alkalization treatment is investigated. aq. solution of sodium hydroxide is added to the dehydrated sludge. Iron phosphate in the sludge react with sodium hydroxide, forming sodium phosphate and iron hydroxide containing-sludge at room tem...

The wastewater treatment produces a large amount of sludge. The different uses of eliminations sludge such as landfills or incineration have consequences negative for the environment, the agricultural use has increased worldwide, especially in crops and few or no studies have been conducted with forest plantations in Algeria. The objective of this study is to assess fertilizing characteristics ...

The rheological characteristics of digested sludge are severely temperature dependent. An effect of temperature on rheological properties of digested sludge is partially irreversible. In this paper, the effects of temperature change and thermal history on viscosity of digested sludge were studied using a stress-controlled rheometer which was connected to a temperature controlled water bath. Dig...