Seeking Potential Anomalous Levels of Exposure to PCDD/Fs and PCBs through Sewage Sludge Characterization

2016 ◽  
pp. 125-142 ◽  
Keyword(s):  
Sewage Sludge ◽  
Sludge Characterization

Correlation between electrical and rheological measurements on sewage sludge

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
E. Dieudé-Fauvel ◽  
J.-C. Baudez ◽  
P. Coussot ◽  
H. Van Damme
Keyword(s):  
Sewage Sludge ◽  
Rheological Parameters ◽  
Clear Correlation ◽  
Electrical Measurements ◽  
Rheological Measurements ◽  
Sludge Characterization ◽  
Relaxation Experiments ◽  
Rheological Experiments ◽  
The One ◽  
Microstructure Of The Material

In order to improve sewage sludge characterization for both dewatering and agricultural spreading, we have studied their electrical and rheological properties. On the one hand, electrical measurements give a picture of the microstructure of the material (charges, particles mobility), whereas on the other hand, rheological experiments describe its macrostructure (consistency). The interactions of the matter are the link between them. Our results showed that sludge becomes more conductive when its dry content (for a defined composition) or the temperature increases, and also during aging. In parallel its apparent viscosity increases with the dry content but decreases with the temperature or during aging. In each case a clear correlation was found between electrical and rheological parameters. This relationship clearly depends on sludge composition, and also on parameters such as the temperature, the observation frequency, the velocity range in the case of relaxation experiments. Finally, those types of experiments can be correlated to improve the comprehension of sludge structure and consistency characterization.

The Use of Rheology for Sludge Characterization

1982 ◽  
Vol 14 (6-7) ◽  
pp. 475-489 ◽  
Author(s):  
H W Campbell ◽  
P J Crescuolo
Keyword(s):  
Particle Size ◽  
Sewage Sludge ◽  
Test Procedures ◽  
Particle Size Reduction ◽  
Rotational Viscometer ◽  
Polymer Addition ◽  
Rheological Measurements ◽  
Acceleration Rate ◽  
Sludge Characterization ◽  
Potential Use

Rheological measurements were conducted on a variety of anaerobically digested sewage sludges to evaluate the potential use of rheology in describing the effects of chemical conditioning on the physical characteristics of sludges. The objectives of the study were to evaluate the influence of the method of chemical conditioning on rheological measurements; to determine the response of the viscometer system to changes in the instrument variables; and to evaluate interrelationships between rheology and other physical properties. All rheological measurements were made using a coaxial rotational viscometer. Evaluation of a variety of test procedures identified that both the method of adding chemical conditioners, and the acceleration rate of the rotational viscometer, could significantly alter the shape of the rheograms. A suggested methodology was identified and selected samples were analyzed in triplicate to test the reproducibility of the procedures. Existing mathematical models do not adequately describe the variety of flow behaviour patterns observed with sewage sludge. The concepts of yield stress and apparent viscosity also have limited value due to problems of definition and calculation. A parameter termed the “instantaneous viscosity”, defined as the derivative of the flow curve, is suggested as being more suitable for describing sludge behaviour. The relationships between chemical conditioning, particle size distribution and applied shear were explored. As polymer addition increased, the sludge particles became more susceptible to shear breakup. The extent of particle size reduction was a function of the rate of shear and the time during which the shear was maintained.

Sludge characterization: the rôle of physical consistency

2004 ◽  
Vol 49 (10) ◽  
pp. 59-65 ◽  
Author(s):  
L. Spinosa ◽  
K. Wichmann
Keyword(s):  
Sewage Sludge ◽  
Analytical Methods ◽  
Field Tests ◽  
Treatment Utilization ◽  
European Directives ◽  
Boundary Limit ◽  
Sludge Characterization ◽  
Almost All ◽  
All Treatment

The physical consistency is an important parameter in sewage sludge characterization as it strongly affects almost all treatment, utilization and disposal operations. In addition, in many European Directives a reference to the physical consistency is reported as a characteristic to be evaluated for fulfilling the regulations’ requirements. Further, in many analytical methods for sludge, different procedures are indicated depending on whether a sample is liquid or not, is solid or not. Three physical behaviours (liquid, paste-like and solid) can be observed with sludges, so the development of analytical procedures to define the boundary limit between liquid and paste-like behaviours (flowability) and that between solid and pastelike ones (solidity) is of growing interest. Several devices can be used for evaluating the flowability and solidity properties, but often they are costly and difficult to be operated in the field. Tests have been carried out to evaluate the possibility to adopt a simple extrusion procedure for flowability measurements, and a Vicat needle for solidity ones.

Magnetic bugs cut sewage sludge

Nature ◽  
2003 ◽  
Author(s):  
John Whitfield
Keyword(s):  
Sewage Sludge

A long-term chemical and infrared spectroscopy study on a soil amended with municipal sewage sludge

Agronomie ◽  
2001 ◽  
Vol 21 (2) ◽  
pp. 169-178 ◽  
Author(s):  
Giovanni Gigliotti ◽  
Pier Lodovico Giusquiani ◽  
Daniela Businelli
Keyword(s):  
Infrared Spectroscopy ◽  
Sewage Sludge ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Spectroscopy Study
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