There are important differences in the environmental perspectives and costs involved in mechanical sludge dewatering followed by disposal on agricultural land compared to reed bed sludge treatment. The effect on the environment of the operation of a Sludge Treatment in Reed Beds system is seen as quite limited compared to traditional sludge treatment systems such as mechanical dewatering and dr...

Sludge drying reed bed (SDRB) is a technology adopted to treat sludge from septic tanks, latrines, or anaerobic and aerobic reactors. The sludge is loaded by pumping on vegetated beds, and treated by a combination of physical and biochemical processes. The dewatering of the sludge is due to a combined effect of drainage and evapotranspiration. The organic matter reduction of the sludge is drive...

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...

Sludge produced in wastewater treatment plants (WWTPs) reaches around 1% of the wastewater volume treated whilst the processes for sludge handling and disposal represent from 20 to 60% of operating costs. It is widely recognised that sludge for disposal is one of the most critical issues today for WWTPs operators. The tendency of many countries seems to be aimed towards a biowaste prevention wh...

Policy of energy conservation and emission reduction has been advocated during recent years in China. The development of wastewater treatment has presented some problems with a huge sludge production and high operating cost. Eutrophication occurred frequently in many water bodies of China and discharge standards for wastewater treatment plants (WTTPs) are strict with nutrient removal. However, ...

The treatment and disposal of excess sludge has been a rising challenge for wastewater treatment plants worldwide. In this study, simultaneous sludge reduction and nutrient removal was evaluated in laboratory scale sequencing batch reactors (SBRs). Two SBRs were operated alongside for a duration of 370d. One SBR was operated to achieve nutrient removal (control-SBR) at 10d solids retention time...

Sewage sludge is a considerable source of greenhouse gas (GHG) emission in the field of organic solid waste treatment and disposal. In this case study, total GHG emissions from sludge anaerobic digestion, including direct and indirect emissions as well as replaceable emission reduction due to biogas being reused instead of natural gas, were quantified respectively. The results indicated that no...

This paper presents three new approaches to reduce excess sludge production in activated sludge systems: 1) modification of conventional activated sludge process with insertion of a sludge holding tank in the sludge return line; 2) chlorination of excess sludge so as to minimize excess sludge production; and 3) utilization of a metabolic uncoupler, 3, 3', 4', 5-Tetrachlorosalicylanilide (TCS) t...

The use of Fenton's reagent (Fe2+/H2O2) and Fenton-like reagents containing transition metals of Cu(II), Zn(II), Co(II), and Mn(II) for an alum sludge conditioning to improve its dewaterability was investigated. The results obtained were compared with those obtained from conditioning the same alum sludge using cationic and anionic polymers. Experimental results show that Fenton's reagent was th...