Study of calcium carbonate and sulfate co-precipitation

Handle URI:
http://hdl.handle.net/10754/562790
Title:
Study of calcium carbonate and sulfate co-precipitation
Authors:
Zarga, Y.; Ben Boubaker, H.; Ghaffour, Noreddine ( 0000-0003-2095-4736 ) ; Elfil, Hamza
Abstract:
Co-precipitation of mineral based salts in scaling is still not well understood and/or thermodynamically well defined in the water industry. This study focuses on investigating calcium carbonate (CaCO3) and sulfate mixed precipitation in scaling which is commonly observed in industrial water treatment processes including seawater desalination either by thermal-based or membrane-based processes. Co-precipitation kinetics were studied carefully by monitoring several parameters simultaneously measured, including: pH, calcium and alkalinity concentrations as well as quartz microbalance responses. The CaCO3 germination in mixed precipitation was found to be different than that of simple precipitation. Indeed, the co-precipitation of CaCO3 germination time was not anymore related to supersaturation as in a simple homogenous precipitation, but was significantly reduced when the gypsum crystals appeared first. On the other hand, the calcium sulfate crystals appear to reduce the energetic barrier of CaCO3 nucleation and lead to its precipitation by activating heterogeneous germination. However, the presence of CaCO3 crystals does not seem to have any significant effect on gypsum precipitation. IR spectroscopy and the Scanning Electronic Microscopy (SEM) were used to identify the nature of scales structures. Gypsum was found to be the dominant precipitate while calcite and especially vaterite were found at lower proportions. These analyses showed also that gypsum crystals promote calcite crystallization to the detriment of other forms. © 2013 Elsevier Ltd.
KAUST Department:
Water Desalination and Reuse Research Center (WDRC)
Publisher:
Elsevier BV
Journal:
Chemical Engineering Science
Issue Date:
Jun-2013
DOI:
10.1016/j.ces.2013.03.028
Type:
Article
ISSN:
00092509
Appears in Collections:
Articles; Water Desalination and Reuse Research Center (WDRC)

Full metadata record

DC FieldValue Language
dc.contributor.authorZarga, Y.en
dc.contributor.authorBen Boubaker, H.en
dc.contributor.authorGhaffour, Noreddineen
dc.contributor.authorElfil, Hamzaen
dc.date.accessioned2015-08-03T11:05:51Zen
dc.date.available2015-08-03T11:05:51Zen
dc.date.issued2013-06en
dc.identifier.issn00092509en
dc.identifier.doi10.1016/j.ces.2013.03.028en
dc.identifier.urihttp://hdl.handle.net/10754/562790en
dc.description.abstractCo-precipitation of mineral based salts in scaling is still not well understood and/or thermodynamically well defined in the water industry. This study focuses on investigating calcium carbonate (CaCO3) and sulfate mixed precipitation in scaling which is commonly observed in industrial water treatment processes including seawater desalination either by thermal-based or membrane-based processes. Co-precipitation kinetics were studied carefully by monitoring several parameters simultaneously measured, including: pH, calcium and alkalinity concentrations as well as quartz microbalance responses. The CaCO3 germination in mixed precipitation was found to be different than that of simple precipitation. Indeed, the co-precipitation of CaCO3 germination time was not anymore related to supersaturation as in a simple homogenous precipitation, but was significantly reduced when the gypsum crystals appeared first. On the other hand, the calcium sulfate crystals appear to reduce the energetic barrier of CaCO3 nucleation and lead to its precipitation by activating heterogeneous germination. However, the presence of CaCO3 crystals does not seem to have any significant effect on gypsum precipitation. IR spectroscopy and the Scanning Electronic Microscopy (SEM) were used to identify the nature of scales structures. Gypsum was found to be the dominant precipitate while calcite and especially vaterite were found at lower proportions. These analyses showed also that gypsum crystals promote calcite crystallization to the detriment of other forms. © 2013 Elsevier Ltd.en
dc.publisherElsevier BVen
dc.subjectFoulingen
dc.subjectGypsumen
dc.subjectKineticsen
dc.subjectNucleationen
dc.subjectPrecipitationen
dc.subjectSupersaturationen
dc.titleStudy of calcium carbonate and sulfate co-precipitationen
dc.typeArticleen
dc.contributor.departmentWater Desalination and Reuse Research Center (WDRC)en
dc.identifier.journalChemical Engineering Scienceen
dc.contributor.institutionLabTEN-Water Technologies Research Center, Technopole of Borj-Cédria, Tunisiaen
kaust.authorGhaffour, Noreddineen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.