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.

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.

EFFECT OF MOISTURE AND PARTICLE SIZE ON THE COMBUSTION CHARACTERISTICS OF SEWAGE SLUDGE IN A FIXED BED

2018 ◽  
Author(s):  
Joana Freitas Campana ◽  
Kaio Pandolfi Pessotti ◽  
Carlos Eduardo Silva Abreu ◽  
Patrick de Jesus
Keyword(s):  
Particle Size ◽  
Sewage Sludge ◽  
Fixed Bed ◽  
Combustion Characteristics ◽  
Effect Of Moisture

Methods for particle size reduction of liposomal amphotericin B

2018 ◽  
Vol 60 (1) ◽  
pp. 42-45
Author(s):  
Tuan Quang Nguyen ◽  
Van Lam Nguyen ◽  
Thai Son Nguyen ◽  
Thi Minh Hue Pham ◽  
◽  
...  
Keyword(s):  
Particle Size ◽  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
Size Reduction ◽  
Liposomal Amphotericin B ◽  
Particle Size Reduction

scholarly journals Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Prasedya ◽  
A. Frediansyah ◽  
N. W. R. Martyasari ◽  
B. K. Ilhami ◽  
A. S. Abidin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Particle Size ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Ethanol Extract ◽  
Total Phenolic ◽  
Particle Sizes ◽  
Epicatechin Gallate ◽  
Particle Size Reduction ◽  
Phytochemical Composition

AbstractSample particle size is an important parameter in the solid–liquid extraction system of natural products for obtaining their bioactive compounds. This study evaluates the effect of sample particle size on the phytochemical composition and antioxidant activity of brown macroalgae Sargassum cristaefolium. The crude ethanol extract was extracted from dried powders of S.cristeafolium with various particle sizes (> 4000 µm, > 250 µm, > 125 µm, > 45 µm, and < 45 µm). The ethanolic extracts of S.cristaefolium were analysed for Total Phenolic Content (TPC), Total Flavonoid Content (TFC), phenolic compound concentration and antioxidant activities. The extract yield and phytochemical composition were more abundant in smaller particle sizes. Furthermore, the TPC (14.19 ± 2.08 mg GAE/g extract to 43.27 ± 2.56 mg GAE/g extract) and TFC (9.6 ± 1.8 mg QE/g extract to 70.27 ± 3.59 mg QE/g extract) values also significantly increased as particle sizes decreased. In addition, phenolic compounds epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and Epigallocatechin gallate (EGCG) concentration were frequently increased in samples of smaller particle sizes based on two-way ANOVA and Tukey’s multiple comparison analysis. These results correlate with the significantly stronger antioxidant activity in samples with smaller particle sizes. The smallest particle size (< 45 µm) demonstrated the strongest antioxidant activity based on DPPH, ABTS, hydroxyl assay and FRAP. In addition, ramp function graph evaluates the desired particle size for maximum phytochemical composition and antioxidant activity is 44 µm. In conclusion, current results show the importance of particle size reduction of macroalgae samples to increase the effectivity of its biological activity.

scholarly journals Laser Superficial Fusion of Gold Nanoparticles with PEEK Polymer for Cardiovascular Application

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 971
Author(s):  
Oktawian Bialas ◽  
Mateusz Lis ◽  
Anna Woźniak ◽  
Marcin Adamiak
Keyword(s):  
Particle Size ◽  
Laser Beam ◽  
Gold Particle ◽  
Laser Power ◽  
Biomedical Application ◽  
Parameters Optimization ◽  
Size Reduction ◽  
Particle Size Reduction ◽  
Nano Gold ◽  
Gold Particle Size

This paper analyses the possibility of obtaining surface-infused nano gold particles with the polyether ether ketone (PEEK) using picosecond laser treatment. To fuse particles into polymer, the raw surface of PEEK was sputtered with 99.99% Au and micromachined by an A-355 laser device for gold particle size reduction. Biomimetic pattern and parameters optimization were key properties of the design for biomedical application. The structures were investigated by employing surface topography in the presence of micron and sub-micron features. The energy of the laser beam stating the presence of polymer bond thermalisation with remelting due to high temperature was also taken into the account. The process was suited to avoid intensive surface modification that could compromise the mechanical properties of fragile cardiovascular devices. The initial material analysis was conducted by power–depth dependence using confocal microscopy. The evaluation of gold particle size reduction was performed with scanning electron microscopy (SEM), secondary electron (SE) and quadrant backscatter electron detector (QBSD) and energy dispersive spectroscopy (EDS) analysis. The visibility of the constituted coating was checked by a commercial grade X-ray that is commonly used in hospitals. Attempts to reduce deposited gold coating to the size of Au nanoparticles (Au NPs) and to fuse them into the groove using a laser beam have been successfully completed. The relationship between the laser power and the characteristics of the particles remaining in the laser irradiation area has been established. A significant increase in quantity was achieved using laser power with a minimum power of 15 mW. The obtained results allowed for the continuation of the pilot study for augmented research and material properties analysis.

Effect of particle size and delignification on the rate of digestion of hemicellulose and cellulose by cellulase in mature pangola grass stems

1983 ◽  
Vol 34 (3) ◽  
pp. 241 ◽  
Author(s):  
CW Ford
Keyword(s):  
Particle Size ◽  
Cell Walls ◽  
Trichoderma Viride ◽  
Structural Features ◽  
Cell Wall Polysaccharides ◽  
Particle Size Reduction ◽  
Digitaria Decumbens ◽  
Hemicellulose Degradation ◽  
Before And After ◽  
The Difference

Stem cell walls of pangola grass (Digitaria decumbens) were ground to two particle sizes (c. 1 and 0.1 mm diameter), and incubated with cellulase (ex. Trichoderma viride) for varying times before and after delignification. Total cell walls finely ground (0.1 mm) with a Spex Shatterbox mill were initially degraded more rapidly (to 24 h) than delignified 1 mm particles. Thereafter the delignified material was solubilized to a greater extent. Subsequent specific determinations of cell wall polysaccharides indicated that delignification increased the rate of hemicellulose degradation to a greater extent than did particle size reduction, whereas the opposite was found for cellulose. The difference between delignified and Spex-ground residues, in terms of the amount of polysaccharide digested, was much greater for cellulose than hemicellulose. It is concluded that structural features play a more important role in limiting cellulase degradation of cellulose than does association with lignin, the reverse being so for hemicellulose.

scholarly journals Characterization of Astaxanthin Nanoemulsions Produced by Intense Fluid Shear through a Self-Throttling Nanometer Range Annular Orifice Valve-Based High-Pressure Homogenizer

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2856
Author(s):  
Gary B. Smejkal ◽  
Edmund Y. Ting ◽  
Karthik Nambi Arul Nambi ◽  
Richard T. Schumacher ◽  
Alexander V. Lazarev
Keyword(s):  
Particle Size ◽  
Size Reduction ◽  
Hydrodynamic Diameter ◽  
Fluid Shear ◽  
Particle Size Reduction ◽  
Annular Gap ◽  
Oil In Water ◽  
High Pressure Homogenizer ◽  
Pass Through

Stable, oil-in-water nanoemulsions containing astaxanthin (AsX) were produced by intense fluid shear forces resulting from pumping a coarse reagent emulsion through a self-throttling annular gap valve at 300 MPa. Compared to crude emulsions prepared by conventional homogenization, a size reduction of over two orders of magnitude was observed for AsX-encapsulated oil droplets following just one pass through the annular valve. In krill oil formulations, the mean hydrodynamic diameter of lipid particles was reduced to 60 nm after only two passes through the valve and reached a minimal size of 24 nm after eight passes. Repeated processing of samples through the valve progressively decreased lipid particle size, with an inflection in the rate of particle size reduction generally observed after 2–4 passes. Krill- and argan oil-based nanoemulsions were produced using an Ultra Shear Technology™ (UST™) approach and characterized in terms of their small particle size, low polydispersity, and stability.

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