Spatial and temporal evolution of floc size distribution in a stirred square tank investigated using PIV and image analysis

2006 ◽  
Vol 61 (23) ◽  
pp. 7651-7667 ◽  
Author(s):  
J. Kilander ◽  
S. Blomström ◽  
A. Rasmuson
Keyword(s):  
Image Analysis ◽  
Size Distribution ◽  
Temporal Evolution ◽  
Floc Size

Hydrodynamic conditioning of aluminium–bentonite flocs

2006 ◽  
Vol 6 (1) ◽  
pp. 11-19 ◽  
Author(s):  
C. Coufort ◽  
A. Liné
Keyword(s):  
Image Analysis ◽  
Size Distribution ◽  
High Sensitivity ◽  
Size Distributions ◽  
Hydrodynamic Stress ◽  
Floc Size ◽  
Micro Scale ◽  
Break Up ◽  
Floc Size Distributions

The aim of this paper is to analyse the role of hydrodynamics in flocculation. The effects of a hydrodynamic sequencing (flocculation–break-up–reflocculation–break-up–reflocculation) on the evolution of aluminium–bentonite floc size distributions and structure are investigated by image analysis in a Taylor–Couette reactor. The flocculation phenomena analysed in this study mainly occur in the viscous subrange, with floc size below the Kolmogorov micro-scale. The high sensitivity of steady-state floc size distribution to initial floc size distribution (elementary particles or flocs formed issuing break-up stages) is highlighted. Reversibility or irreversibility of agglomeration and break-up phenomena are discussed in terms of floc history and hydrodynamic stress. Finally, the hydrodynamic conditioning for aluminium–bentonite flocs is examined.

Simultaneous determination of activated sludge floc size distribution by different techniques

2004 ◽  
Vol 50 (12) ◽  
pp. 39-46 ◽  
Author(s):  
R. Govoreanu ◽  
H. Saveyn ◽  
P. Van der Meeren ◽  
P.A. Vanrolleghem
Keyword(s):  
Image Analysis ◽  
Activated Sludge ◽  
Size Distribution ◽  
Bimodal Distribution ◽  
Pilot Scale ◽  
Automated Image Analysis ◽  
Image Analysis System ◽  
Floc Size ◽  
In Series ◽  
Log Normal

The activated sludge floc size distribution (FSD) is investigated by using different techniques and the results are compared against each other in order to gain insight into the FSD characteristics, as well as to detect the limitations of each measurement technique. The experimental set-up consisted of three devices coupled in series: a MastersizerS, an automated image analysis system (IMAN) and a CIS-100. The latter instrument has two measurement channels, based on time of transition (TOT), and image analysis (SHAPE) principles. In order to minimise the variability between successive measurements, the activated sludge samples collected from a pilot-scale SBR were flocculated until steady state was achieved. The results show that the MastersizerS and SHAPE devices yield similar volume weighted FSD. In contrast, the IMAN overestimated the floc size and TOT frequently showed a bimodal distribution. The number distributions from TOT and SHAPE were in agreement, while those generated by the MastersizerS were mainly located in the submicron range and those of IMAN corresponded to larger sizes. The experimental distributions show a good fit to the log-normal model. It is shown that the measurement principle is of utmost importance and results transformation may lead to data misinterpretation.

Spatial variation of and the factors influencing the floc size distribution in the North Yellow Sea during the winter season

2021 ◽  
Vol 442 ◽  
pp. 106660
Author(s):  
Wenjian Li ◽  
Zhenyan Wang ◽  
Guan-hong Lee ◽  
Steven Miguel Figueroa ◽  
Haijun Huang
Keyword(s):  
Spatial Variation ◽  
Size Distribution ◽  
Yellow Sea ◽  
Winter Season ◽  
Floc Size ◽  
North Yellow Sea ◽  
The North ◽  
Factors Influencing

Floc Size Distribution Measurements: A Physically Sound Method for Scaling Up Flocculation Performance

1996 ◽  
pp. 41-48
Author(s):  
B. S. Lartiges ◽  
L. S. Derrendinger ◽  
J. Y. Bottero ◽  
C. Democrate ◽  
J. F. Coupel ◽  
...  
Keyword(s):  
Size Distribution ◽  
Scaling Up ◽  
Floc Size

scholarly journals Pore system changes of damaged Brazilian oxisols and nitosols induced by wet-dry cycles as seen in 2-D micromorphologic image analysis

2009 ◽  
Vol 81 (1) ◽  
pp. 151-161 ◽  
Author(s):  
Luiz F. Pires ◽  
Klaus Reichardt ◽  
Miguel Cooper ◽  
Fabio A.M. Cássaro ◽  
Nivea M.P. Dias ◽  
...  
Keyword(s):  
Image Analysis ◽  
Size Distribution ◽  
Soil Structure ◽  
Tropical Soils ◽  
Transport Processes ◽  
Structure Characterization ◽  
Control Treatment ◽  
Simple Method ◽  
Wetting And Drying ◽  
Essential Information

Soil pore structure characterization using 2-D image analysis constitutes a simple method to obtain essential information related to soil porosity and pore size distribution (PSD). Such information is important to infer on soil quality, which is related to soil structure and transport processes inside the soil. Most of the time soils are submitted to wetting and drying cycles (W-D), which can cause important changes in soils with damaged structures. This report uses 2-D image analysis to evaluate possible modifications induced by W-D cycles on the structure of damaged soil samples. Samples of three tropical soils (Geric Ferralsol, GF; Eutric Nitosol, EN; and Rhodic Ferralsol, RF) were submitted to three treatments: 0WD, the control treatment in which samples were not submitted to any W-D cycle; 3WD and 9WD with samples submitted to 3 and 9 consecutive W-D cycles, respectively. It was observed that W-D cycles produced significant changes in large irregular pores of the GF and RF soils, and in rounded pores of the EN soil. Nevertheless, important changes in smaller pores (35, 75, and 150 µm) were also observed for all soils. As an overall consideration, it can be said that the use of image analysis helped to explain important changes in soil pore systems (shape, number, and size distribution) as consequence of W-D cycles.

scholarly journals Temporal evolution and spatial distribution of dust creation events in Tore Supra and in ASDEX Upgrade studied by CCD image analysis

2010 ◽  
Vol 50 (3) ◽  
pp. 035002 ◽  
Author(s):  
Suk-Ho Hong ◽  
Christian Grisolia ◽  
Volker Rohde ◽  
Pascale Monier-Garbet ◽  
◽  
...  
Keyword(s):  
Image Analysis ◽  
Spatial Distribution ◽  
Temporal Evolution ◽  
Ccd Image
Sign in / Sign up

Export Citation Format

Share Document