Treatment of cooling tower blowdown water containing silica, calcium and magnesium by electrocoagulation
This research investigated the effectiveness of electrocoagulation using iron and aluminium electrodes for treating cooling tower blowdown (CTB) waters containing dissolved silica (Si(OH)(4)), Ca(2 + ) and Mg(2 + ). The removal of each target species was measured as a function of the coagulant dose...
| Veröffentlicht in: | Water science and technology : a journal of the International Association on Water Pollution Research. - 1986. - 60(2009), 9 vom: 24., Seite 2345-52 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2009
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| Zugriff auf das übergeordnete Werk: | Water science and technology : a journal of the International Association on Water Pollution Research |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Ferric Compounds Water Pollutants, Chemical Water 059QF0KO0R ferric hydroxide 2UA751211N Silicon Dioxide 7631-86-9 mehr... |
| Zusammenfassung: | This research investigated the effectiveness of electrocoagulation using iron and aluminium electrodes for treating cooling tower blowdown (CTB) waters containing dissolved silica (Si(OH)(4)), Ca(2 + ) and Mg(2 + ). The removal of each target species was measured as a function of the coagulant dose in simulated CTB waters with initial pH values of 5, 7, and 9. Experiments were also performed to investigate the effect of antiscaling compounds and coagulation aids on hardness ion removal. Both iron and aluminum electrodes were effective at removing dissolved silica. For coagulant doses < or =3 mM, silica removal was a linear function of the coagulant dose, with 0.4 to 0.5 moles of silica removed per mole of iron or aluminium. Iron electrodes were only 30% as effective at removing Ca(2 + ) and Mg(2 + ) as compared to silica. There was no measurable removal of hardness ions by aluminium electrodes in the absence of organic additives. Phosphonate based antiscaling compounds were uniformly effective at increasing the removal of Ca(2 + ) and Mg(2 + ) by both iron and aluminium electrodes. Cationic and amphoteric polymers used as coagulation aids were also effective at increasing hardness ion removal |
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| Beschreibung: | Date Completed 11.01.2010 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
| ISSN: | 0273-1223 |
| DOI: | 10.2166/wst.2009.675 |