Capillary suction time (CST) as a measure of sludge dewaterability

1996 ◽  
Vol 34 (3-4) ◽  
pp. 443-448 ◽  
Author(s):  
G. W. Chen ◽  
W. W. Lin ◽  
D. J. Lee
Keyword(s):  
Water Content ◽  
Specific Resistance ◽  
Bound Water ◽  
The Other ◽  
Solid Concentration ◽  
Capillary Suction ◽  
Good Index ◽  
Other Hand ◽  
Sludge Dewaterability ◽  
Bound Water Content

The feasibility of employment of capillary suction time (CST) for characterizing the dewaterability of excess activated sludges was examined. The CST was shown as a good index for sludge filterability, if only the product of solid concentration and average specific resistance is of interest. On the other hand, the bound water content cannot be directly evaluated from the CST data.

Conditioning effect of lysozyme combined with freeze-thaw on the municipal sludge dewatering performance

BioResources ◽  
2019 ◽  
Vol 14 (3) ◽  
pp. 7375-7386
Author(s):  
Feng Lin ◽  
Jigeng Li ◽  
Xiaolin Zhu ◽  
Peiran Yu ◽  
Mengru Liu
Keyword(s):  
Water Content ◽  
Bound Water ◽  
Municipal Sludge ◽  
Sludge Dewatering ◽  
Capillary Suction ◽  
Freeze Thaw ◽  
Floc Structure ◽  
Conditioning Effect ◽  
Dewatered Sludge ◽  
Bound Water Content

The effects of lysozyme (LZM) and freeze-thaw conditioning, alone or in combination, on sludge dewatering performance were comparatively investigated. After the optimization of the dewatering conditions using response surface methodology (RSM), the co-conditioning exhibited obvious superiority to the separate conditioning in improving the dewaterability of municipal sludge, with the capillary suction time (CST) and the water content (W) of the dewatered sludge reduced to 12 ± 0.5 s and 52.0% ± 0.4% from 61.8 s and 73.0%, respectively. The co-conditioning appeared not only to destroy the structure of extracellular polymeric substance (EPS) and microbial cell wall by virtue of enzymatic conditioning, but it formed larger particles and compact sludge floc structure with the help of freeze-thaw conditioning. Additionally, the bound water content of sludge decreased by 47.5% after co-conditioning, consistent with the enhancement in sludge dewaterability. All the results showed that LZM in combination with freeze-thaw conditioning had a great potential in sludge reduction, providing more opportunity of resource utilization for the dewatered sludge.

Effect of charge neutralization on the dewatering performance of alum sludge by polymer conditioning

2001 ◽  
Vol 44 (10) ◽  
pp. 315-319 ◽  
Author(s):  
C.C. Wu ◽  
J.J. Wu
Keyword(s):  
Water Content ◽  
Bound Water ◽  
Cationic Polymer ◽  
Anionic Polymer ◽  
Capillary Suction ◽  
Potential Measurement ◽  
Charge Neutralization ◽  
Floc Structure ◽  
Alum Sludge ◽  
Bound Water Content

Cationic and anionic polymers with the same molecular weight were used as sludge conditioning reagent to study the polymer charge effect on alum sludge dewatering characteristics. On the basis of capillary suction time, bound water content, and zeta-potential measurement in this study, the function of charge neutralization appears to be an important consideration in the sludge dewaterability and moisture content. Using the dilatometric technique to measure the bound water content, we found that alum sludge conditioned by cationic polymer presented more significant variation in the bound water content than sludge subject to anionic conditioning. We hypothesise that the mechanism of charge neutralization caused much water depletion by replacement and exclusion in sludge and results in the decrease of bound water within the cationic polymer conditioning. An insignificant bound water variation found during the anionic conditioning resulted from the lack of charge neutralization. A lighter and looser floc structure is also be found in the anionic conditioned sludge after the analysis of wet floc density and fractal dimension. Such open floc structure can be attributed to the lack of charge neutralization as the flocs aggregate with anionic polymer.

scholarly journals Bound Water Content of Vegetative and Spore Forms of Bacteria

1938 ◽  
Vol 36 (1) ◽  
pp. 99-105 ◽  
Author(s):  
C. A. Friedman ◽  
B. S. Henry
Keyword(s):  
Water Content ◽  
Bound Water ◽  
Bound Water Content

scholarly journals Studies on the Maximum Bound Water Content by the Differential Scanning Calorimetry on Lipstick

2012 ◽  
Vol 38 (3) ◽  
pp. 197-200
Author(s):  
Khee-Hwan Choi ◽  
Myung-Jin Ann ◽  
Hong-Ha Son ◽  
Kyong-Seub Kim ◽  
Sang-Min Lee ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Water Content ◽  
Bound Water ◽  
Scanning Calorimetry ◽  
Bound Water Content

scholarly journals The influence of different sludge concentrations on its dewaterability during bioleaching

2020 ◽  
Vol 81 (12) ◽  
pp. 2585-2598
Author(s):  
Wenfeng Yang ◽  
Liyuan Zeng ◽  
Weihao Zhang ◽  
Qiyong Yang ◽  
Tianfeng Wang ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Reduction Potential ◽  
High Efficiency ◽  
Specific Resistance ◽  
Principal Component ◽  
Buffering Capacity ◽  
Capillary Suction ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Sludge Dewaterability

Abstract Bioleaching, a technologically and economically feasible technology, is considered as the high efficiency method to improve dewaterability in sewage sludge. The objective of this study was to investigate the effect of different sludge concentrations on bioleaching dewaterability and understand the mechanism of the effect of bioleaching on sludge dewaterability. Variation in pH, oxidation-reduction potential (ORP), capillary suction time (CST), specific resistance to filtration (SRF) and different fractions of extracellular polymeric substances (EPS) including slime EPS (S-EPS), loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS) were determined. Different sludge concentrations (5, 10, 15, 20 and 30 g·L−1) were selected to investigate during bioleaching. Results indicated that sludge buffering capacity significantly inhibited bioleaching efficiency as sludge concentrations increased. Optimum enhancements in sludge dewaterability were observed during the 10 g·L−1 sludge concentration treatment, and reached a maximum when the pH was 2.11. The variation of different fractions of EPS revealed that the ratio of S-EPS/TB-EPS significantly affected sludge dewaterability. Principal component analysis and Pearson's correlation analysis both provided evidence that the higher TB-EPS followed by a very large reduction was positively correlated with sludge dewaterability. However, the increase of protein and DNA in S-EPS content was negatively correlated with sludge dewaterability.

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