The measurement of magnesium : a possible key to struvite production and process control
Struvite, a crystalline structure comprised of ions of magnesium (Mg2+), ammonium (NH4-N) and phosphate (PO4-P), is commonly encountered in wastewater treatmentplants (WWTPs) through struvite encrustation. The gradual growth of this crystal can lead to h igh maintenance costs, due to downtime and re...
| Veröffentlicht in: | Environmental technology. - 1998. - 29(2008), 6 vom: 21. Juni, Seite 603-12 |
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| Weitere Verfasser: | , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2008
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| Zugriff auf das übergeordnete Werk: | Environmental technology |
| Schlagworte: | Evaluation Study Journal Article Magnesium Compounds Phosphates Water 059QF0KO0R Struvite AW3EJL1462 Magnesium I38ZP9992A |
| Zusammenfassung: | Struvite, a crystalline structure comprised of ions of magnesium (Mg2+), ammonium (NH4-N) and phosphate (PO4-P), is commonly encountered in wastewater treatmentplants (WWTPs) through struvite encrustation. The gradual growth of this crystal can lead to h igh maintenance costs, due to downtime and replacement parts. Several struvite recovery unit processes have been developed in an effort to reduce this problem, through the preferential removal of the constituent ions (Mg2+, NH4-N, and PO4-P) upstream of problem areas (e.g. anaerobic digester supernatants). One of the key elements of process control for these systems is accurately determining the constituent concentrations. Although a wide variety of measurement techniques exist for both NH4-N and PO4-P, the presence of PO4-P interferes with the measurement of Mg2+. Ion selective electrodes (ISEs) were tested on wastewater samples to determine Mg2+ concentrations. It was found that the two ISE tested produced unreliable results, as they both proved non-specific t o Mg2+. A modification, using polyaluminum chloride (PAC), was developed to remove the interference of phosphates from the colorimetric technique. It was found to produce reliable results within 10% of those results predicted by atomic absorption. The resulting technique averaged about 10 minutes per sample and could be conducted inexpensively at a laboratory facility at WWTPs |
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| Beschreibung: | Date Completed 30.09.2008 Date Revised 10.12.2019 published: Print Citation Status MEDLINE |
| ISSN: | 0959-3330 |
| DOI: | 10.1080/09593330801984365 |