Quantification of Wind Induced Resuspension in a Shallow Lake

The mass balance of suspended solids in a shallow lake was modelled as the net result of resuspension and settling. Four different formulations for the flux of resuspension were used. Two equations were based on the conception of wave induced resuspension, the other two used the flow field induced shear stress as the driving force for resuspension. Parameter estimations based on experimental time series of wind velocity and SS concentration produced lower least square values with the models based on flow induced resuspension. The model parameter representing settling was in reasonable accordance with the settling velocity obtained from sediment traps. The spread in results can be explained by a lack of homogeneity and horizontal transport.

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Effect of Starch on the Flocculation and Settling Behaviour of Titanium Dioxide Suspensions

Water Quality Research Journal ◽

10.2166/wqrj.1974.017 ◽

1974 ◽

Vol 9 (1) ◽

pp. 154-171

Author(s):

S.N. Ray ◽

C. Hsi ◽

B.C. -Y. Lu

Keyword(s):

Titanium Dioxide ◽

Suspended Solids ◽

Settling Velocity ◽

Pollution Abatement ◽

Paper Mills ◽

Paper Making ◽

Jar Test ◽

Settling Behaviour ◽

Dimensionless Function ◽

Flocculation Rate

Abstract This study concerns the problem of removal of suspended solids from the effluent streams of paper mills by chemical treatment. As titanium dioxide is one of the ingredients used in paper mills and present in the effluent streams, its flocculation and settling behaviour were investigated. Jar test experiments were conducted using alum and organic polyelectrolyte as the flocculants. As starch is also used in the paper making process, its influence on the flocculation and settling behaviour of titanium dioxide was conducted with the concentration of starch varying between 0–3% of the dry solids. The experimental results on flocculation are expressed in terms of dimensionless function Gθϕ and flocculation rate constants. The fraction of solids settled is presented in terms of the settling velocity. Concentration of starch was found to have a significant influence. The amount of alum required could be reduced by 75% by using starch 0.6% of the amount of titanium dioxide in the suspension and at the same time improving the settling velocity two folds. A possible application of this finding in pollution abatement is discussed.

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Methods for determining the settling velocity profiles of solids in storm sewage

Water Science & Technology ◽

10.2166/wst.1996.0190 ◽

1996 ◽

Vol 33 (9) ◽

pp. 117-125 ◽

Cited By ~ 5

Author(s):

Emmanuelle Aiguier ◽

Ghassan Chebbo ◽

Jean-Luc Bertrand-Krajewski ◽

Peter Hedges ◽

Naomi Tyack

Keyword(s):

Suspended Solids ◽

Settling Velocity ◽

Test Procedure ◽

Velocity Profiles ◽

Test Methods ◽

Efficient Treatment ◽

Experimental Procedure ◽

Comparative Tests ◽

Settling Process ◽

Settling Characteristics

Recently, research has shown that a settling process is an efficient treatment for the removal of suspended solids from storm sewage. In order to design settling tanks, there is a need to determine the settling velocity characteristics of these solids. Devices and test methods for measuring settling velocities of solids in storm sewage have been developed by researchers. A literature review has revealed that the settling velocity profiles obtained with some methods (Chebbo, 1992), (Michelbach and Wohrle, 1993) and (Tyack et al., 1993) are very different. In order to explain why the results are different and to quantify the influence of the experimental procedure on the settling velocity grading curves, we have compared the selected methods when tested with the same sample and we have studied the effects of the conservation of the sample before the test, of the concentration of solids in the device and of the nature of the water on the settling velocity profiles. The results of the comparative tests indicate that the settling velocities are significantly lower with both the Cergrene and Aston methods than with the UFT test procedure. Moreover, the study has shown that the settling characteristics of solids change with time, that the use of sewage liquor rather than demineralised water or drinking water can change the results of the measurement and that the higher the concentration of solids, the greater the velocity of settled particles.

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The Least Square Values for Games with Restricted Cooperation

SSRN Electronic Journal ◽

10.2139/ssrn.2364998 ◽

2013 ◽

Cited By ~ 1

Author(s):

Ilya V. Katsev

Keyword(s):

Least Square ◽

Restricted Cooperation ◽

Least Square Values

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Calibration of three resuspension/sedimentation models

Water Science & Technology ◽

10.2166/wst.1998.0171 ◽

1998 ◽

Vol 37 (3) ◽

pp. 41-49 ◽

Cited By ~ 3

Author(s):

Gerard Blom ◽

R. Hans Aalderink

Keyword(s):

Suspended Solids ◽

Statistical Evaluation ◽

Model Fit ◽

Parameter Estimates ◽

Flume Experiments ◽

Parameter Estimations ◽

In Situ Observations ◽

Squared Residuals ◽

Very High

Three resuspension and sedimentation models (Blom, Lick and Partheniades and Krone) are calibrated and evaluated on data from flume experiments with sediments from Lake Ketel and in situ suspended solids measurements. We applied a formal parameter estimation technique in combination with a statistical evaluation of the model fit and parameter estimates. All three models produce a reasonable reconstruction of the data from the flume experiment and the in situ observations. The differences in the model fit of the three models are small, except for the in situ observations. Here the sum of squared residuals for Partheniades and Krone's is about twice the sum for Blom's and Lick's model. The correlation between parameters in resuspension/sedimentation models can be very high, leading to an uncertainty in parameter estimates of 25-50. The parameter estimations based on the flume data are up to orders of magnitude higher than those estimated from field observations.

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KINERJA JACKKNIFE RIDGE REGRESSION DALAM MENGATASI MULTIKOLINEARITAS

E-Jurnal Matematika ◽

10.24843/mtk.2014.v03.i04.p077 ◽

2014 ◽

Vol 3 (4) ◽

pp. 146

Author(s):

HANY DEVITA ◽

I KOMANG GDE SUKARSA ◽

I PUTU EKA N. KENCANA

Keyword(s):

Linear Correlation ◽

Ridge Regression ◽

Minimum Variance ◽

Sum Of Squares ◽

Least Square ◽

Bias Parameter ◽

Ridge Estimator ◽

Ordinary Least Square ◽

Parameter Estimations

Ordinary least square is a parameter estimations for minimizing residual sum of squares. If the multicollinearity was found in the data, unbias estimator with minimum variance could not be reached. Multicollinearity is a linear correlation between independent variabels in model. Jackknife Ridge Regression(JRR) as an extension of Generalized Ridge Regression (GRR) for solving multicollinearity. Generalized Ridge Regression is used to overcome the bias of estimators caused of presents multicollinearity by adding different bias parameter for each independent variabel in least square equation after transforming the data into an orthoghonal form. Beside that, JRR can reduce the bias of the ridge estimator. The result showed that JRR model out performs GRR model.

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Patterns of gross deposition in reservoirs enriched in inorganic tripton

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f01-163 ◽

2001 ◽

Vol 58 (11) ◽

pp. 2177-2188 ◽

Cited By ~ 9

Author(s):

Steven W Effler ◽

Carol M Matthews (Brooks) ◽

David A Matthews

Keyword(s):

New York ◽

Suspended Solids ◽

Inorganic Material ◽

Settling Velocity ◽

Particulate Phosphorus ◽

Overlying Water ◽

Longitudinal Gradients ◽

The Individual ◽

Carbon Particulate ◽

Inorganic Components

Magnitudes and patterns in the deposition of chlorophyll (Chl), organic carbon, particulate phosphorus (PP), and suspended solids are documented for seven New York reservoirs based on analyses of metalimnetic and near-bottom sediment trap collections. Inorganic material dominated the trap collections and caused a decoupling of the downward fluxes of Chl and PP because of major contributions of inorganic components to P deposition. These contributions were manifested in the stoichiometry of trap collections, the much higher estimates of settling velocity (SV) for PP compared with Chl, and differences in patterns of Chl and PP deposition within individual reservoirs and among these systems. Most of the deposited phosphorus in these reservoirs (7198%) was associated with nonphytoplankton particles. In contrast to the other constituents, the estimates of SV for Chl were lower and more uniform; nearly 50% of the individual estimates (n = 188) were between 0.15 and 0.25 m·day1. Longitudinal gradients in sediment deposition occurred as a result of gradients in both overlying water concentrations and settling characteristics of the particles. Seasonal and vertical patterns in trap collections and budget calculations indicate that resuspension contributed to deposition, to varying extents, in all of the reservoir basins.

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