The role of blending in polymer conditioning of waste activated sludge

This paper presents the results of an investigation on the role of blending in sludge polymer conditioning by evaluating the polymer consumption, and measuring the capillary suction time of waste activated sludge samples blended for different time periods. All of the sludge samples, including non-blended control samples, were conditioned by a cationic high molecular weight polymer in desired concentrations. The protein concentrations of the sludge samples increased as a biological confirmation of cell disruption or desorption of some part of biological polymers present in sludge. Blending decreased the critical polymer dosages required to condition the waste activated sludge samples depending on the blending time applied to the samples.

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Extracellular polymers of ozonized waste activated sludge

Water Science & Technology ◽

10.2166/wst.2001.0602 ◽

2001 ◽

Vol 44 (10) ◽

pp. 137-142 ◽

Cited By ~ 17

Author(s):

J.C. Liu ◽

C.H. Lee ◽

J.Y. Lai ◽

K.C. Wang ◽

Y.C. Hsu ◽

...

Keyword(s):

Molecular Weight ◽

Activated Sludge ◽

Weight Distribution ◽

Specific Resistance ◽

Optimal Dose ◽

Cationic Polyelectrolyte ◽

Waste Activated Sludge ◽

Extracellular Polymers ◽

Capillary Suction ◽

Ozone Dose

Effect of ozonation on characteristics of waste activated sludge was investigated in the current study. Concentrations of cell-bound extracellular polymers (washed ECPs) did not change much upon ozonation, whereas the sum of cell-bound and soluble extracellular polymers (unwashed ECPs) increased with increasing ozone dose. Washed ECPs in original sludge as divided by molecular weight distribution was 39% < 1,000 Da (low MW), 30% from 1,000 to 10,000 Da (medium MW), and 31% > 10,000 Da (high MW). It was observed that the low-MW fraction decreased, and the high-MW fraction increased in ozonized sludge. The unwashed ECPs were characterized as 44% in low MW, 30% in medium MW, and 26% in high MW. Both low-MW and medium-MW fractions of unwashed ECPs decreased while high-MW fraction increased in ozonized sludge. The dewaterability of ozonized sludge, assessed by capillary suction time (CST) and specific resistance to filtration (SRF), deteriorated with ozone dose. The optimal dose of cationic polyelectrolyte increased with increasing ozone dose. The production rate and the accumulated amount of methane gas of ozonized sludge were also higher.

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Role of highly branched, high molecular weight polymer structures in directing uniform polymer particle formation during nanoprecipitation

Chemical Communications ◽

10.1039/c6cc00611f ◽

2016 ◽

Vol 52 (20) ◽

pp. 3915-3918 ◽

Cited By ~ 4

Author(s):

Fiona L. Hatton ◽

Pierre Chambon ◽

Alison C. Savage ◽

Steve P. Rannard

Keyword(s):

Molecular Weight ◽

Growth Mechanism ◽

Nucleation And Growth ◽

Polymer Particle ◽

Branched Polymers ◽

High Molecular Weight Polymer ◽

Molecular Weight Polymer ◽

Mixing Techniques ◽

Nucleation And Growth Mechanism

The presence of highly branched polymers with >100 conjoined primary chains is shown to induce a novel rapid nucleation and growth mechanism within polymer nanoprecipitation yielding functional, uniform nanoparticles without stabilisers, filtration or rapid mixing techniques.

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