The role of inorganic ions in the calcium carbonate scaling of seawater reverse osmosis systems

Handle URI:
http://hdl.handle.net/10754/562042
Title:
The role of inorganic ions in the calcium carbonate scaling of seawater reverse osmosis systems
Authors:
Waly, Tarek; Kennedy, Maria Dolores; Witkamp, Geert-Jan; Amy, Gary L.; Schippers, Jan Cornelis
Abstract:
In supersaturated solutions the period preceding the start of 'measurable' crystallization is normally referred to as the 'induction time'. This research project aimed to investigate the induction times of CaCO 3 in the presence of Mg 2+ and SO 4 2-. The prepared synthetic solutions have the same ionic strength values found in the Gulf of Oman SWRO concentrates at 30% and 50% recovery. The results showed a significant increase in the induction time by 1140%, 2820%, and 3880% for a recovery of 50%, when adding SO 4 2- only, Mg 2+ only, or both Mg 2+ and SO 4 2-, respectively, to synthetic SWRO concentrate compared to that obtained in the absence of Mg 2+ and SO 4 2- at an initial pH of 8.3. The increase in the induction time in the presence of SO 4 2- was more than likely to be due to nucleation and growth inhibition while the presence of Mg 2+ affected the nucleation and growth through both complexation and inhibition. After a 5-month solution stabilization period, ESEM and XRD analyses showed aragonite in solutions containing Mg 2+. On the contrary, calcite was the final crystal phase formed in solutions with no Mg 2+. This suggests that magnesium may play an important role in inhibiting the formation of calcite. © 2011 Elsevier B.V..
KAUST Department:
Water Desalination and Reuse Research Center (WDRC); Biological and Environmental Sciences and Engineering (BESE) Division
Publisher:
Elsevier
Journal:
Desalination
Issue Date:
Jan-2012
DOI:
10.1016/j.desal.2011.09.012
Type:
Article
ISSN:
00119164
Appears in Collections:
Articles; Water Desalination and Reuse Research Center (WDRC); Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorWaly, Tareken
dc.contributor.authorKennedy, Maria Doloresen
dc.contributor.authorWitkamp, Geert-Janen
dc.contributor.authorAmy, Gary L.en
dc.contributor.authorSchippers, Jan Cornelisen
dc.date.accessioned2015-08-03T09:43:26Zen
dc.date.available2015-08-03T09:43:26Zen
dc.date.issued2012-01en
dc.identifier.issn00119164en
dc.identifier.doi10.1016/j.desal.2011.09.012en
dc.identifier.urihttp://hdl.handle.net/10754/562042en
dc.description.abstractIn supersaturated solutions the period preceding the start of 'measurable' crystallization is normally referred to as the 'induction time'. This research project aimed to investigate the induction times of CaCO 3 in the presence of Mg 2+ and SO 4 2-. The prepared synthetic solutions have the same ionic strength values found in the Gulf of Oman SWRO concentrates at 30% and 50% recovery. The results showed a significant increase in the induction time by 1140%, 2820%, and 3880% for a recovery of 50%, when adding SO 4 2- only, Mg 2+ only, or both Mg 2+ and SO 4 2-, respectively, to synthetic SWRO concentrate compared to that obtained in the absence of Mg 2+ and SO 4 2- at an initial pH of 8.3. The increase in the induction time in the presence of SO 4 2- was more than likely to be due to nucleation and growth inhibition while the presence of Mg 2+ affected the nucleation and growth through both complexation and inhibition. After a 5-month solution stabilization period, ESEM and XRD analyses showed aragonite in solutions containing Mg 2+. On the contrary, calcite was the final crystal phase formed in solutions with no Mg 2+. This suggests that magnesium may play an important role in inhibiting the formation of calcite. © 2011 Elsevier B.V..en
dc.publisherElsevieren
dc.subjectCaCO 3 polymorphsen
dc.subjectInduction timeen
dc.subjectMg 2+en
dc.subjectScalingen
dc.subjectSO 4 2-en
dc.subjectSWROen
dc.titleThe role of inorganic ions in the calcium carbonate scaling of seawater reverse osmosis systemsen
dc.typeArticleen
dc.contributor.departmentWater Desalination and Reuse Research Center (WDRC)en
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.identifier.journalDesalinationen
dc.contributor.institutionUNESCO-IHE, Delft, Netherlandsen
dc.contributor.institutionTUDelft, Delft, Netherlandsen
dc.contributor.institutionDOW Chemical IMEA, Saudi Arabiaen
kaust.authorAmy, Gary L.en
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