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Vasyliev G, Vasylieva S, Novosad A, Gerasymenko Y. Ultrasonic modification of carbonate scale electrochemically deposited in tap water. ULTRASONICS SONOCHEMISTRY 2018; 48:57-63. [PMID: 30080586 DOI: 10.1016/j.ultsonch.2018.05.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
Influence of the ultrasound intensity (28 kHz, 1.1-7.5 W/cm2) on CaCO3 nucleation-growth on the surface of a cylinder mild steel electrode rotating at 500 rpm was studied in tap water. The deposition kinetics was analyzed by chronoamperometry; the calcareous layer was characterized by gravimetry, scanning electron microscopy and XRD. Application of ultrasound to calcium carbonate crystallization affects nucleation site density, mass-transport rate and cavitation erosion of the deposits. Lower intensity ultrasound reduces scale porosity and area density by increasing nucleation site density and accelerating the mass transport. Higher intensity ultrasound promotes cavitation erosion of the formed layer, thus cleaning the surface from the scale. A scale layer with the highest blocking properties formed under applied ultrasound intensity of 1.9 W/cm2. The ultrasound doubled crystallization rate, reduced the scale porosity 5 times and halved its area density compared to non-sonicated conditions. Ultrasound of controllable intensity can solve both scale and corrosion problems of industrial heat-exchange equipment by forming a protective scale layer and removing excessive deposits.
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Affiliation(s)
- G Vasyliev
- National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", 37, Prospect Peremohy, 03056, Kyiv-056, Ukraine.
| | - S Vasylieva
- National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", 37, Prospect Peremohy, 03056, Kyiv-056, Ukraine
| | - A Novosad
- National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", 37, Prospect Peremohy, 03056, Kyiv-056, Ukraine
| | - Y Gerasymenko
- National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", 37, Prospect Peremohy, 03056, Kyiv-056, Ukraine
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Sanni O, Bukuaghangin O, Huggan M, Kapur N, Charpentier T, Neville A. Development of a novel once-through flow visualization technique for kinetic study of bulk and surface scaling. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:103903. [PMID: 29092516 DOI: 10.1063/1.4991729] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
There is a considerable interest to investigate surface crystallization in order to have a full mechanistic understanding of how layers of sparingly soluble salts (scale) build on component surfaces. Despite much recent attention, a suitable methodology to improve on the understanding of the precipitation/deposition systems to enable the construction of an accurate surface deposition kinetic model is still needed. In this work, an experimental flow rig and associated methodology to study mineral scale deposition is developed. The once-through flow rig allows us to follow mineral scale precipitation and surface deposition in situ and in real time. The rig enables us to assess the effects of various parameters such as brine chemistry and scaling indices, temperature, flow rates, and scale inhibitor concentrations on scaling kinetics. Calcium carbonate (CaCO3) scaling at different values of the saturation ratio (SR) is evaluated using image analysis procedures that enable the assessment of surface coverage, nucleation, and growth of the particles with time. The result for turbidity values measured in the flow cell is zero for all the SR considered. The residence time from the mixing point to the sample is shorter than the induction time for bulk precipitation; therefore, there are no crystals in the bulk solution as the flow passes through the sample. The study shows that surface scaling is not always a result of pre-precipitated crystals in the bulk solution. The technique enables both precipitation and surface deposition of scale to be decoupled and for the surface deposition process to be studied in real time and assessed under constant condition.
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Affiliation(s)
- O Sanni
- School of Mechanical Engineering, Institute of Functional Surfaces, University of Leeds, Leeds, United Kingdom
| | - O Bukuaghangin
- School of Mechanical Engineering, Institute of Functional Surfaces, University of Leeds, Leeds, United Kingdom
| | - M Huggan
- School of Mechanical Engineering, Institute of Functional Surfaces, University of Leeds, Leeds, United Kingdom
| | - N Kapur
- School of Mechanical Engineering, Institute of Thermofluids, University of Leeds, Leeds, United Kingdom
| | - T Charpentier
- School of Chemical and Process Engineering, University of Leeds, Leeds, United Kingdom
| | - A Neville
- School of Mechanical Engineering, Institute of Functional Surfaces, University of Leeds, Leeds, United Kingdom
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He S, Xu R, Wang J, Han S, Chen B. Temperature effects on the kinetics of a PbO2 electrosynthesis process in an alkaline bath. RSC Adv 2016. [DOI: 10.1039/c6ra16803e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
An electrochemical investigation of temperature on the electrosynthesis of lead dioxide in alkaline solutions was performed using a rotating disk electrode (RDE).
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Affiliation(s)
- Shiwei He
- Faculty of Metallurgical and Energy Engineering
- Kunming University of Science and Technology
- Kunming 650093
- China
- School of Metallurgical Engineering
| | - Ruidong Xu
- Faculty of Metallurgical and Energy Engineering
- Kunming University of Science and Technology
- Kunming 650093
- China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization
| | - Jiong Wang
- Faculty of Metallurgical and Energy Engineering
- Kunming University of Science and Technology
- Kunming 650093
- China
| | - Sha Han
- Faculty of Metallurgical and Energy Engineering
- Kunming University of Science and Technology
- Kunming 650093
- China
| | - Buming Chen
- Faculty of Metallurgical and Energy Engineering
- Kunming University of Science and Technology
- Kunming 650093
- China
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Zaslavschi I, Shemer H, Hasson D, Semiat R. Rotating cylinder technique for assessing the effectiveness of anti-scalants. WATER RESEARCH 2013; 47:3716-3722. [PMID: 23726708 DOI: 10.1016/j.watres.2013.04.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 04/04/2013] [Accepted: 04/15/2013] [Indexed: 06/02/2023]
Abstract
A novel technique for evaluating the relative inhibition effectiveness of different anti-scalants is presented. The technique is based on the ability of anti-scalants to modify the scale deposition mechanism from mass transfer control to surface control. A rotating cylinder system which is known to provide well controlled mass transfer conditions is used to determine the scaling rate of a supersaturated solution dosed with various feed concentrations of an anti-scalant. Mass transfer conditions were characterized by turbulent flow at hydrodynamically smooth surface. In the absence of an anti-scalant, scale deposition is mass transfer controlled and scaling rate increases with rotation speed. With sufficient anti-scalant dosage, precipitation is modified to surface control and rotation speed has no effect on the scale deposition rate. Determination of the critical anti-scalant dosage enabling surface controlled precipitation provides a sensitive technique for comparing the relative effectiveness of different anti-scalants.
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Affiliation(s)
- Irina Zaslavschi
- Technion-Israel Institute of Technology, Department of Chemical Engineering, Rabin Desalination Laboratory-Grand Water Research Institute, Haifa 32000, Israel
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Wang H, Alfredsson V, Tropsch J, Ettl R, Nylander T. Formation of CaCO3 deposits on hard surfaces--effect of bulk solution conditions and surface properties. ACS APPLIED MATERIALS & INTERFACES 2013; 5:4035-45. [PMID: 23597231 DOI: 10.1021/am401348v] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We have studied nucleation and crystal growth of calcium carbonate on hard surfaces, i.e. stainless steel and silica, at different temperatures, in relation to the corresponding bulk processes, using scanning electron microscopy (SEM), X-ray diffraction (XRD), and ellipsometry. In the bulk solution, a mixture of all three calcium carbonate crystalline polymorphs, calcite, aragonite, and vaterite, as well as amorphous particles was observed at 25 °C, while at 55 °C aragonite and calcite crystals dominated. On surfaces only calcite crystals were observed at 25 °C, whereas aragonite and calcite crystal adsorbed on the surfaces at 55 °C. Two kinds of nucleation and adsorption mechanism of CaCO3 crystals on hard surfaces were observed, depending on the surface orientation (vertical or horizontal, i.e., subject to sedimentation) in the bulk solution. A model for the relation between interfacial layer structure, the substrate, and the solution crystallization is discussed based on the observed difference in deposition between type of surfaces and surface orientation. In addition, the effect of magnesium ion on the morphology of calcium carbonate crystals is discussed.
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Affiliation(s)
- Hao Wang
- Physical Chemistry, Lund University, Lund, Sweden
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Boerkamp M, Lamb DW, Lye PG, Fellows CM, Al-Hamzah A, Wallace AD. Detecting and Monitoring Industrial Scale Formation Using an Intrinsic Exposed-Core Optical Fiber Sensor. Ind Eng Chem Res 2010. [DOI: 10.1021/ie901471p] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Martijn Boerkamp
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - David W. Lamb
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - Peter G. Lye
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - Christopher M. Fellows
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - Ali Al-Hamzah
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - Andrew D. Wallace
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
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Webster NAS, Madsen IC, Loan MJ, Scarlett NVY, Wallwork KS. A flow cell for in situ synchrotron x-ray diffraction studies of scale formation under Bayer processing conditions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:084102. [PMID: 19725670 DOI: 10.1063/1.3183494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The design, construction, and commissioning of a stainless steel flow cell for in situ synchrotron x-ray diffraction studies of scale formation under Bayer processing conditions is described. The use of the cell is demonstrated by a study of Al(OH)(3) scale formation on a mild steel substrate from synthetic Bayer liquor at 70 degrees C. The cell design allows for interchangeable parts and substrates and would be suitable for the study of scale formation in other industrial processes.
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Abdel-Gaber A, Abd-El-Nabey B, Khamis E, Abd-El-Khalek D. Investigation of fig leaf extract as a novel environmentally friendly antiscalent for CaCO3 calcareous deposits. DESALINATION 2008; 230:314-328. [DOI: 10.1016/j.desal.2007.12.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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12
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EIS characterization of the evolution of calcium carbonate scaling in cooling systems in presence of inhibitors. J Solid State Electrochem 2007. [DOI: 10.1007/s10008-007-0279-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Marín-Cruz J, García-Figueroa E, Miranda-Hernández M, González I. Electrochemical treatments for selective growth of different calcium carbonate allotropic forms on carbon steel. WATER RESEARCH 2004; 38:173-183. [PMID: 14630115 DOI: 10.1016/j.watres.2003.08.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Different allogropic forms of calcium carbonate scales (calcite and aragonite) were electrochemically deposited on carbon steel surfaces, using different electrochemical techniques: cyclic voltammetry or potentiostatic pulses. To simulate conditions of Mexican refinery cooling systems, this study was performed in the presence of known concentrations of other salts at pH 7.8 and 40 degrees C with low and high calcium carbonate concentrations. Reduction reactions for dissolved oxygen and water occurring in such systems modified the pH at the substrate-solution interface to promote scaling of the calcium carbonate present. A systematic scanning electron microscopy and X-ray diffraction analysis of the carbon steel surface showed that the formation of calcite and aragonite depended on the initial state of substrate surface (clean or damaged) and on the concentration of calcium carbonate present in the system.
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Affiliation(s)
- J Marín-Cruz
- Universidad Autónoma Metropolitana, Departamento de Química. Apdo. Postal 55-534, 09340, D.F., México, Mexico
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Morizot AP, Neville A. Insights into Electrodeposition of an Inhibitor Film and Its Inhibitive Effects on Calcium Carbonate Deposition. J Colloid Interface Sci 2002; 245:40-9. [PMID: 16290333 DOI: 10.1006/jcis.2001.7963] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2001] [Accepted: 09/03/2001] [Indexed: 11/22/2022]
Abstract
Polycarboxylic acid (PAA), a common scale inhibitor has demonstrated adsorption properties on stainless steel surfaces. An electrochemically based technique has been used to assess the extent of film formation. The presence of calcium and magnesium ions in the solution and the cathodic electrochemical activity at the metal surface have been shown to enhance the inhibitor film formation by promoting the transport of the inhibitor from the solution to the metal surface. The effect of the inhibitor film in retarding scale deposition is assessed using measurement of the deposition onto metal electrodes immersed in a supersaturated solution of CaCO(3). The practical implications of these findings are discussed.
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Affiliation(s)
- Arnaud P Morizot
- Corrosion and Surface Engineering Research Group, Department of Mechanical and Chemical Engineering, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, United Kingdom
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Neville A, Morizot A. A combined bulk chemistry/electrochemical approach to study the precipitation, deposition and inhibition of CaCO3. Chem Eng Sci 2000. [DOI: 10.1016/s0009-2509(00)00046-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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