Arsenic Leaching from Mineral Sorbents under Landfill Conditions and Arsenic Transport by Wind

Persistent Link:
http://hdl.handle.net/10150/347223
Title:
Arsenic Leaching from Mineral Sorbents under Landfill Conditions and Arsenic Transport by Wind
Author:
Guzman Grijalva, Hector Manuel
Issue Date:
2014
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Embargo:
Dissertation not available in either the UA Campus Repository or the ProQuest Dissertations and Theses database, at the request of the author.
Abstract:
The capacity of four mineral sorbents to retain arsenic under simulated mature landfill conditions was tested using semi-batch and continuous flow columns. The sorbents tested were Fe-, Ti-, La-, and Zr- based oxi(hydroxides). The Fe sorbent was included as a positive control to compare the release of As from a substrate subject to reduction to those of the, non-sensitive to reduction under typical mature landfill conditions, Ti, La, and Zr media. It has been proved that under mature landfill conditions, As(V) preloaded on ferric sorbents is prompt to be released at high levels. Our results indicate that Ti, La, and Zr sorbents can release As at a similar or higher degree than a ferric sorbent. In a second phase, the capacity of the same sorbents to retain As was evaluated after being subject to polymeric encapsulation in an epoxic resin. Landfill conditions were simulated by use of semi-batch column systems packed with compost and fed with actual landfill leachate. Results obtained indicated that encapsulation highly enhanced As retention of the media under simulated landfill conditions. In our research regarding soil contamination by atmospheric transport from mine tailings, a previously developed deposition forecasting model (DFM) that is designed to model the transport of particulate As and Pb from mine tailing impoundments is verified using dust collection and topsoil measurements. The forecast deposition patterns are compared to dust collected by inverted-disc samplers through gravimetric, chemical composition and lead isotopic analysis. The DFM is capable of predicting dust deposition patterns from the tailings impoundment to the surrounding area. Finally, the bioaccessibility of As and Pb were on samples collected at Iron King Mine Tailing was evaluated through chemical extractions using simulated the gastric and the lung fluids of the human body. Results obtained indicate that extractions using simulated gastric fluid lead to As concentrations one order of magnitude higher to those obtained with lung fluid. For Pb concentration the difference was greater than 2 orders of magnitude.
Type:
text; Electronic Dissertation
Keywords:
Arsenic transport by wind; Bioaccessibility; Encapsulation; Landfill; Mineral sorbents; Environmental Engineering; Environmental Engineering
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Environmental Engineering
Degree Grantor:
University of Arizona
Advisor:
Ela, Wendell P.; Saez, Avelino E.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen
dc.titleArsenic Leaching from Mineral Sorbents under Landfill Conditions and Arsenic Transport by Winden_US
dc.creatorGuzman Grijalva, Hector Manuelen_US
dc.contributor.authorGuzman Grijalva, Hector Manuelen_US
dc.date.issued2014en
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.releaseDissertation not available in either the UA Campus Repository or the ProQuest Dissertations and Theses database, at the request of the author.en_US
dc.description.abstractThe capacity of four mineral sorbents to retain arsenic under simulated mature landfill conditions was tested using semi-batch and continuous flow columns. The sorbents tested were Fe-, Ti-, La-, and Zr- based oxi(hydroxides). The Fe sorbent was included as a positive control to compare the release of As from a substrate subject to reduction to those of the, non-sensitive to reduction under typical mature landfill conditions, Ti, La, and Zr media. It has been proved that under mature landfill conditions, As(V) preloaded on ferric sorbents is prompt to be released at high levels. Our results indicate that Ti, La, and Zr sorbents can release As at a similar or higher degree than a ferric sorbent. In a second phase, the capacity of the same sorbents to retain As was evaluated after being subject to polymeric encapsulation in an epoxic resin. Landfill conditions were simulated by use of semi-batch column systems packed with compost and fed with actual landfill leachate. Results obtained indicated that encapsulation highly enhanced As retention of the media under simulated landfill conditions. In our research regarding soil contamination by atmospheric transport from mine tailings, a previously developed deposition forecasting model (DFM) that is designed to model the transport of particulate As and Pb from mine tailing impoundments is verified using dust collection and topsoil measurements. The forecast deposition patterns are compared to dust collected by inverted-disc samplers through gravimetric, chemical composition and lead isotopic analysis. The DFM is capable of predicting dust deposition patterns from the tailings impoundment to the surrounding area. Finally, the bioaccessibility of As and Pb were on samples collected at Iron King Mine Tailing was evaluated through chemical extractions using simulated the gastric and the lung fluids of the human body. Results obtained indicate that extractions using simulated gastric fluid lead to As concentrations one order of magnitude higher to those obtained with lung fluid. For Pb concentration the difference was greater than 2 orders of magnitude.en_US
dc.typetexten
dc.typeElectronic Dissertationen
dc.subjectArsenic transport by winden_US
dc.subjectBioaccessibilityen_US
dc.subjectEncapsulationen_US
dc.subjectLandfillen_US
dc.subjectMineral sorbentsen_US
dc.subjectEnvironmental Engineeringen_US
dc.subjectEnvironmental Engineeringen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineEnvironmental Engineeringen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorEla, Wendell P.en_US
dc.contributor.advisorSaez, Avelino E.en_US
dc.contributor.committeememberArnold, Robert G.en_US
dc.contributor.committeememberEla, Wendell P.en_US
dc.contributor.committeememberSaez, Avelino E.en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.