Quantitative Evaluations with 2D Electrical Resistance Tomography in the Low Conductivity Solutions Using 3D Printed Phantoms for Crystallization Process Monitoring

Crystallization is a significant procedure in the manufacturing of many pharmaceutical and solid food products. In-situ electrical resistance tomography (ERT) is a novel process analytical tool (PAT) to provide a cheap and quick way to test, visualize, and evaluate the progress of crystallization processes. In this work, the spatial accuracy of the nonconductive phantoms in low-conductivity solutions was evaluated. Gauss–Newton, linear back projection, and iterative total variation reconstruction algorithms were used to compare the phantom reconstructions for tap water, industrial-grade saturated sucrose solution, and demineralized water. A cylindrical phantom measuring 10 mm in diameter and a cross-section area of 1.5% of the total beaker area was detected at the center of the beaker. Two phantoms with a 10-mm diameter were visualized separately in noncentral locations. The quantitative evaluations were done for the phantoms with radii ranging from 10 mm to 50 mm in demineralized water. Multiple factors, such as ERT device and sensor development, Finite Element Model (FEM) mesh density and simulations, image reconstruction algorithms, number of iterations, segmentation methods, and morphological image processing methods, were discussed and analyzed to achieve spatial accuracy. The development of ERT imaging modality for the purpose of monitoring crystallization in low-conductivity solutions was performed satisfactorily.

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Using electrical resistance tomography to characterize and optimize the mixing of micron sized polymeric particles in a slurry reactor

10.32920/ryerson.14662842 ◽

2021 ◽

Author(s):

Parisa Tahvildarian

Keyword(s):

Electrical Resistance ◽

Tap Water ◽

Slurry Reactor ◽

Operating Conditions ◽

Impeller Speed ◽

Design Parameters ◽

Electrical Resistance Tomography ◽

Latex Particles ◽

Liquid Mixing ◽

Solid Liquid

A solid-liquid mixing system has a significant role in the suspension polymerization, crystallization, adsorption, and solid-catalyzed reactions. In this study, Electrical Resistance Tomography (ERT) was employed to investigate the effect of the particle size, the design parameters such as impeller type, impeller clearance and impeller diameter as well as operating conditions such as impeller speed, impeller pumping mode, and solids concentration on the mixing of micron sized latex particles in a slurry reactor. The ERT data were used to calculate the concentration profile and the degree of homogeneity in three dimensions, as a function of design parameters and operating within the reactor. In this work, tap water and latex particles (5.2 µm, 8.5 µm, 9.1 µm) were used as liquid and solid phase, respectively. Six axial impellers were utilized (A310, A100, A200, A320, A315, 3AM) with impeller speed (N) varying from 252 rpm to 400 rpm. Impeller diameter to tank diameter ratios (D/T) were in the range of 0.29 to 0.47 while, the impeller clearance (C/T) was changed in the range of T/3.8 to T/2.5. Impeller pumping was tested in both downward and upward directions. The concentration of latex particles was ranged between 15 wt% and 30 wt%. This study shows that the level of homogeneity in a solid-liquid mixing system improved with the increase in impeller speed. However, after achieving the maximum level of homogeneity, any further rise in the impeller speed had a detrimental effect on the level of homogeneity. A310 impeller, wtih D/T ratio of 0.31, demonstrated the highest level of homogeneity while the upward pumping direction was found to be more efficient than the downward one. In addition, a clearance of T/3 proved to create the highest level of homogeneity. Also, the results showed that a rise in the size and concentration of particles decreases the level of homogeneity. Thus, 5.2 µm latex particles with the concentration of 15 wt% demonstrated the highest level of homogeneity. Applying the findings of this study will lead to improved equipment design, chemical cost reduction, increased production rate, improved quality of products, and more efficient use of power in slurry reactors.

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Process Monitoring of Antisolvent Based Crystallization in Low Conductivity Solutions Using Electrical Impedance Spectroscopy and 2-D Electrical Resistance Tomography

Applied Sciences ◽

10.3390/app10113903 ◽

2020 ◽

Vol 10 (11) ◽

pp. 3903 ◽

Cited By ~ 1

Author(s):

Guruprasad Rao ◽

Soheil Aghajanian ◽

Tuomas Koiranen ◽

Radosław Wajman ◽

Lidia Jackowska-Strumiłło

Keyword(s):

Impedance Spectroscopy ◽

Process Monitoring ◽

Electrical Resistance ◽

Electrical Impedance ◽

Sucrose Solution ◽

Second Order ◽

Electrical Impedance Spectroscopy ◽

Electrical Resistance Tomography ◽

Sucrose Solutions ◽

Phase Spectra

Industrial process monitoring is an important field of research where different chemical processes are monitored and controlled. In this work, electrical impedance spectroscopy (EIS) was used to analyze antisolvent based crystallization of sucrose solutions. The impedance and phase spectra were recorded for four known sucrose concentrations in water, and for each case, four predetermined amounts of ethanol were added. As a result, sixteen different solutions involving sucrose solutions of different concentrations and ethanol to water ratios were analyzed. Significant differences were observed in the magnitude and phase spectra of the solutions in the frequency range of 50 kHz to 300 kHz. The experimentally obtained data from the EIS were converted into frequency response models. Three continuous-time transfer function models of the first-order, second-order, and a second-order with a zero were estimated and compared. In addition, a 2-D electrical resistance tomography (ERT) system with a low conductivity sensor unit was designed and tested with demineralized water, tap water and industrial food grade saturated sucrose solution. Non-conducting phantom and sugar crystals were observed within the saturated sucrose solution using the Bayesian reconstruction algorithm. These demonstrations have the potential to be developed into a multi-frequency ERT systems for monitoring the distribution of the crystals in the reactor. The EIS modality can be a complementary process analytical technology (PAT) tool indicating supersaturation status and provide quality assurance.

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Research on Image Reconstruction Algorithms for Tuber Electrical Resistance Tomography System

MATEC Web of Conferences ◽

10.1051/matecconf/20166817004 ◽

2016 ◽

Vol 68 ◽

pp. 17004

Author(s):

Zili Jiang ◽

Xiang Deng ◽

Shuyi Liu ◽

Yu Tang

Keyword(s):

Image Reconstruction ◽

Electrical Resistance ◽

Reconstruction Algorithms ◽

Electrical Resistance Tomography ◽

Tomography System ◽

Image Reconstruction Algorithms

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Using electrical resistance tomography to characterize and optimize the mixing of micron sized polymeric particles in a slurry reactor

10.32920/ryerson.14662842.v1 ◽

2021 ◽

Author(s):

Parisa Tahvildarian

Keyword(s):

Electrical Resistance ◽

Tap Water ◽

Slurry Reactor ◽

Operating Conditions ◽

Impeller Speed ◽

Design Parameters ◽

Electrical Resistance Tomography ◽

Latex Particles ◽

Liquid Mixing ◽

Solid Liquid

A solid-liquid mixing system has a significant role in the suspension polymerization, crystallization, adsorption, and solid-catalyzed reactions. In this study, Electrical Resistance Tomography (ERT) was employed to investigate the effect of the particle size, the design parameters such as impeller type, impeller clearance and impeller diameter as well as operating conditions such as impeller speed, impeller pumping mode, and solids concentration on the mixing of micron sized latex particles in a slurry reactor. The ERT data were used to calculate the concentration profile and the degree of homogeneity in three dimensions, as a function of design parameters and operating within the reactor. In this work, tap water and latex particles (5.2 µm, 8.5 µm, 9.1 µm) were used as liquid and solid phase, respectively. Six axial impellers were utilized (A310, A100, A200, A320, A315, 3AM) with impeller speed (N) varying from 252 rpm to 400 rpm. Impeller diameter to tank diameter ratios (D/T) were in the range of 0.29 to 0.47 while, the impeller clearance (C/T) was changed in the range of T/3.8 to T/2.5. Impeller pumping was tested in both downward and upward directions. The concentration of latex particles was ranged between 15 wt% and 30 wt%. This study shows that the level of homogeneity in a solid-liquid mixing system improved with the increase in impeller speed. However, after achieving the maximum level of homogeneity, any further rise in the impeller speed had a detrimental effect on the level of homogeneity. A310 impeller, wtih D/T ratio of 0.31, demonstrated the highest level of homogeneity while the upward pumping direction was found to be more efficient than the downward one. In addition, a clearance of T/3 proved to create the highest level of homogeneity. Also, the results showed that a rise in the size and concentration of particles decreases the level of homogeneity. Thus, 5.2 µm latex particles with the concentration of 15 wt% demonstrated the highest level of homogeneity. Applying the findings of this study will lead to improved equipment design, chemical cost reduction, increased production rate, improved quality of products, and more efficient use of power in slurry reactors.

Download Full-text