Mixing of Oil in Water Through Electrical Resistance Tomography and Response Surface Methodology

Abstract

The mixing performance of the oil-in-water dispersion system was evaluated. Using an electrical resistance tomography system composed of two measuring planes, the effect of parameters such as impeller type, impeller speed, oil type, and oil volume fraction on the mixing performance through axial mixing indices were explored. The oil type and the oil volume fraction were identified as the most influential factors on the mixing index. Castor oil, with the highest viscosity of the tested oils, was found as the most difficult oil to disperse. The Scaba impeller was the most efficient impeller in dispersing oil in water. The interactions between oil type and impeller type as well as between impeller speed and oil type, had the greatest impact on the mixing index.

Analysis of the Performance of a High-Speed Scott Turbon Mixer in Immiscible Liquid–Liquid Mixing through Endoscopy, Tomography, CFD, and Statistical Methods

“…To calculate φ, the conductivity distribution achieved from the ERT system was converted to the dispersed phase volume fraction based on Maxwell’s equation as follows where φ, σ c , σ d , and σ mc represent the dispersed phase volume fraction, continuous phase conductivity, dispersed phase conductivity, and the restructured measured conductivity, respectively. Since the dispersed phase (i.e., oil) used in the experiments was considered nonconducting (σ d = 0), the Maxwell equation was simplified to To calculate the mixing index for each measurement plane (MI P ), the 316-pixels centrosymmetric conductivity distribution at each measurement plane was separated into six rings, as depicted in Figure . ,, The values inside of the rings represent the measured conductivities by the ERT system, and they were used to calculate the dispersed phase volume fraction in eq . Then, the mixing index of each plane, MI P , was calculated by the following equation as where N , N i , and (MI) i represent the total number of the measured pixels’ conductivities at each plane, the number of measured pixels’ conductivities of the i th ring, and the mixing index of the i th ring, respectively.…”

“…These variables affect the main aspects of immiscible liquid–liquid emulsions such as drop size, drop size distribution, minimum rotational speed of the impeller to make the dispersions, droplet breakage and coalescence, suspension of the drop, phase inversion, and the effect of the surfactant material on the droplet surface behavior. The effects of these variables are critical to produce and increase the essential interfacial area, which improves mass and heat transfer between the phases. − …”

“…Over the last several years, an advanced noninvasive flow-visualization technique of electrical resistance tomography (ERT) has been widely exploited in both industrial processes and academia due to its high-speed imaging capability. Some of the ERT applications are drainage of porous media, two-phase pipe flow, trickling filters, investigation of single-phase mixing operations, − monitoring of the stability of reaction in a polymerization reactor, assessment of gas hold-up, bubble size, mixing time of two-phase liquid–gas mixing operations, − and assessment of the mixing quality in solid suspensions. − Mirshekari and Pakzad employed ERT to investigate the homogeneity of the two-phase immiscible liquid–liquid system. Kaminoyama et al utilized ERT to monitor the stability of reaction and dispersion states in a suspension polymerization reactor.…”

Design and Optimization of a Finite Element Model for Electrical Resistance Tomography of Human Lungs

“…Based on the different electrical features of the object in the sensitivity field, the ET techniques could be divided into electromagnetic tomography (EMT), electrical capacitance tomography (ECT), electrical impedance tomography (EIT), and electrical resistance tomography (ERT). Based on the principle of electromagnetic induction, the EMT can reconstruct the distribution state of the magnetic permeability for the medium in the sensitivity field [1][2][3][4][5][6]; Based on the principle of capacitance sensitivity, the ECT can reconstruct the distribution state of the dielectric constant for the medium in the sensitivity field [7][8][9][10][11][12][13][14][15][16][17]; Based on the principle of impedance sensitivity, the EIT can reconstruct the distribution state of the complex admittance for the medium in the sensitivity field [18][19][20][21][22][23][24]; Based on the principle of resistance sensing, the ERT can reconstruct the distribution state of the dielectric resistivity/conductivity for the medium in the sensitivity field [25][26][27][28][29][30].…”

Width Optimization of Array Electrode for Human Lung Electrical Resistance Tomography System Based on prior Knowledge

“…Electrical tomography (ET) technology consists of 4 different branches, namely, electrical impedance tomography (EIT) [8][9][10][11][12][13][14], ERT [15][16][17][18][19][20], electrical capacitance tomography (ECT) [21][22][23][24][25][26][27], and electromagnetic tomography (EMT) [28][29][30][31][32][33], among which the ERT technology is a new generation of medical imaging technology and a simplified form of the EIT technology when only the change of conductivity/resistivity of the sensitive field is considered, having three outstanding advantages of functional imaging, no damage, and medical image monitoring. Compared with other monitoring methods, ERT technology has incomparable advantages in real-time monitoring and quantitative evaluation of critical respiratory diseases.…”