results the results of this study showed that the release of soluble chemical oxygen demand (scod) in the supernatant and srf were in the range of 127.9-831 mg/l and 12.48-36.55 m/kg at 10 to 120 min ultrasonic contact time, respectively. in addition, ts and vs decreased from 57.98 and 56.31 to 52.69 and 49.87 mg/l, respectively. despite the significant reduction in the solids, there was no con...

Extracellular polymeric substances (EPS) were quantified in flocculent and aerobic granular sludge developed in two sequencing batch reactors with the same shear force but different settling times. Several EPS extraction methods were compared to investigate how different methods affect EPS chemical characterization, and fluorescent stains were used to visualize EPS in intact samples and 20-mum ...

 A case study is presented in which two modifications of activated sludge treatment of complex chemical wastewater are experimentally compared: a combination of common activated sludge with powdered activated carbon treatment (PACT), and bioaugmentation of activated sludge treatment (BAST). Industrial wastewater of Pars Oil Refinery that was passed through an oil recovery stage was used to inve...

The excessive biological sludge production is one of the disadvantages of aerobic process such as SBR. So the problem of excess sludge production along with its treatment , and disposal in aerobic processes in municipal and industrial waste water can be seen in many parts of the world even in our country . to solve the problem of excess sludge production , reducing in by oxidizing some of t...

The following sludge reduction alternatives were tested in wastewater biological reactors: oxic-settling-anaerobic (OSA-process); ultrasonic disintegration (UD); chlorination (CH); 3,3',4',5tetrachlorosalicylanilide (TCS); and folic acid (FA). Compared to the control system, UD reduced 55% of the sludge production, and greater substrate and nutrient removal efficiency was achieved. CH worsened ...

The effect of polyelectrolytes; cationic and anionic charges and coagulants have been investigated for fresh activated sludge at different concentrations and pH values in a comparative fashion. The results from the experiments indicate that the cationic polyelectrolytes have a significant effluence on the sludge characteristic, degree of flocculation and water quality such as turbidity and SVI....

the excessive biological sludge production is one of the disadvantages of aerobic process such as sbr. so the problem of excess sludge production along with its treatment , and disposal in aerobic processes in municipal and industrial waste water can be seen in many parts of the world even in our country . to solve the problem of excess sludge production , reducing in by oxidizing some of the s...

A sequencing batch reactor (SBR) was inoculated with p-nitrophenol-degrading activated sludge to biodegrade a mixture of monosubstituted phenols: p-nitrophenol (PNP), PNP and o-cresol; and PNP, o-cresol and o-chlorophenol. Settling times were progressively decreased to promote biomass granulation. PNP was completely biodegraded. The PNP and o-cresol mixture was also biodegraded although some tr...