High silica concentration in RO concentrate

A. H. Haidari; G. J. Witkamp; S. G.J. Heijman

doi:10.1016/j.wri.2022.100171

High silica concentration in RO concentrate

A. H. Haidari^*, G. J. Witkamp, S. G.J. Heijman

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

10 Scopus citations

Abstract

Silica scaling is one of the major scaling challenges in Reverse Osmosis (RO). The safe operation practice is to keep the silica concentration below 150 mg/L in RO concentrate. This study addresses the effects of divalent cations such as calcium and magnesium on silica scaling in a seawater RO installation used as a pretreatment to Eutectic Freeze Crystallisation (EFC). Results showed that in the absence of antiscalant and divalent cations a sustained silica concentration of approximately 280 mg/L in concentrate is possible without declining membrane permeability. At a higher concentration of divalent cations, the membrane permeability decreased. Membrane autopsy and analysing destructed membrane showed a relatively low magnesium and a high calcium concentration on the membrane after adding divalent ions into the solutions. It is concluded that in absence of divalent cations and without antiscalant the limits of 150 mg/L silica can be extended to 280 mg/L for 6–8 h.

Original language	English (US)
Article number	100171
Journal	Water Resources and Industry
Volume	27
DOIs	https://doi.org/10.1016/j.wri.2022.100171
State	Published - Jun 2022

Bibliographical note

Funding Information:
We would like to thank Hatenboer-Water for their support and providing RO-equipment for the experiments and ZERO BRINE ( Horizon 2020 project with grant number 730390 ) for their support for writing this article.

Publisher Copyright:
© 2022 The Authors

Keywords

Membrane fouling
PHREEQC
Reverse osmosis
Silica scaling

ASJC Scopus subject areas

Geography, Planning and Development
Water Science and Technology

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10.1016/j.wri.2022.100171

Cite this

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title = "High silica concentration in RO concentrate",

abstract = "Silica scaling is one of the major scaling challenges in Reverse Osmosis (RO). The safe operation practice is to keep the silica concentration below 150 mg/L in RO concentrate. This study addresses the effects of divalent cations such as calcium and magnesium on silica scaling in a seawater RO installation used as a pretreatment to Eutectic Freeze Crystallisation (EFC). Results showed that in the absence of antiscalant and divalent cations a sustained silica concentration of approximately 280 mg/L in concentrate is possible without declining membrane permeability. At a higher concentration of divalent cations, the membrane permeability decreased. Membrane autopsy and analysing destructed membrane showed a relatively low magnesium and a high calcium concentration on the membrane after adding divalent ions into the solutions. It is concluded that in absence of divalent cations and without antiscalant the limits of 150 mg/L silica can be extended to 280 mg/L for 6–8 h.",

keywords = "Membrane fouling, PHREEQC, Reverse osmosis, Silica scaling",

author = "Haidari, {A. H.} and Witkamp, {G. J.} and Heijman, {S. G.J.}",

note = "Funding Information: We would like to thank Hatenboer-Water for their support and providing RO-equipment for the experiments and ZERO BRINE ( Horizon 2020 project with grant number 730390 ) for their support for writing this article. Publisher Copyright: {\textcopyright} 2022 The Authors",

year = "2022",

month = jun,

doi = "10.1016/j.wri.2022.100171",

language = "English (US)",

volume = "27",

journal = "Water Resources and Industry",

issn = "2212-3717",

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TY - JOUR

T1 - High silica concentration in RO concentrate

AU - Haidari, A. H.

AU - Witkamp, G. J.

AU - Heijman, S. G.J.

N1 - Funding Information: We would like to thank Hatenboer-Water for their support and providing RO-equipment for the experiments and ZERO BRINE ( Horizon 2020 project with grant number 730390 ) for their support for writing this article. Publisher Copyright: © 2022 The Authors

PY - 2022/6

Y1 - 2022/6

N2 - Silica scaling is one of the major scaling challenges in Reverse Osmosis (RO). The safe operation practice is to keep the silica concentration below 150 mg/L in RO concentrate. This study addresses the effects of divalent cations such as calcium and magnesium on silica scaling in a seawater RO installation used as a pretreatment to Eutectic Freeze Crystallisation (EFC). Results showed that in the absence of antiscalant and divalent cations a sustained silica concentration of approximately 280 mg/L in concentrate is possible without declining membrane permeability. At a higher concentration of divalent cations, the membrane permeability decreased. Membrane autopsy and analysing destructed membrane showed a relatively low magnesium and a high calcium concentration on the membrane after adding divalent ions into the solutions. It is concluded that in absence of divalent cations and without antiscalant the limits of 150 mg/L silica can be extended to 280 mg/L for 6–8 h.

AB - Silica scaling is one of the major scaling challenges in Reverse Osmosis (RO). The safe operation practice is to keep the silica concentration below 150 mg/L in RO concentrate. This study addresses the effects of divalent cations such as calcium and magnesium on silica scaling in a seawater RO installation used as a pretreatment to Eutectic Freeze Crystallisation (EFC). Results showed that in the absence of antiscalant and divalent cations a sustained silica concentration of approximately 280 mg/L in concentrate is possible without declining membrane permeability. At a higher concentration of divalent cations, the membrane permeability decreased. Membrane autopsy and analysing destructed membrane showed a relatively low magnesium and a high calcium concentration on the membrane after adding divalent ions into the solutions. It is concluded that in absence of divalent cations and without antiscalant the limits of 150 mg/L silica can be extended to 280 mg/L for 6–8 h.

KW - Membrane fouling

KW - PHREEQC

KW - Reverse osmosis

KW - Silica scaling

UR - http://www.scopus.com/inward/record.url?scp=85124030427&partnerID=8YFLogxK

U2 - 10.1016/j.wri.2022.100171

DO - 10.1016/j.wri.2022.100171

M3 - Article

AN - SCOPUS:85124030427

SN - 2212-3717

VL - 27

JO - Water Resources and Industry

JF - Water Resources and Industry

M1 - 100171

ER -

High silica concentration in RO concentrate

Abstract

Bibliographical note

Keywords

ASJC Scopus subject areas

Access to Document

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