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dc.contributor.authorParks, Jeffrey Lynnen_US
dc.date.accessioned2014-03-14T20:46:14Z
dc.date.available2014-03-14T20:46:14Z
dc.date.issued2001-09-18en_US
dc.identifier.otheretd-10022001-110024en_US
dc.identifier.urihttp://hdl.handle.net/10919/35259
dc.description.abstractThe dewatering of arsenic-containing residuals is a process that has received little study in the past. Arsenic that has been removed from water by sorption to ferric or aluminum hydroxides can accumulate in residuals to concentrations many times higher than in the source water. The first part of this study evaluates the effectiveness of lime conditioning as a method for immobilizing this arsenic. As the pH is increased with addition of caustic soda or soda ash, soluble arsenic concentration increases dramatically. However, as the pH is increased with lime, very little arsenic is released back into the water. On the basis of previous research this phenomenon might be attributed to the formation of a calcium arsenate solid. However, this study indicates it is more likely that the soluble calcium neutralizes the negative surface charge on the hydroxide solids at high pH and enhances arsenic sorption compared to when calcium was absent. In many cases arsenic-containing residuals are stored in lagoons and allowed to reside there for months or even years. Many parameters may affect the soluble arsenic concentration and speciation in these lagoons. The second portion of this study gives some baseline conditions for these lagoons, both with and without microbial activity and biological organic matter. In these practical situations it appears that lime can assist in keeping arsenic sorbed to the solids and prevent its release to the environment.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartParksETD10-01-01.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectCalciumen_US
dc.subjectArsenicen_US
dc.subjectLeachabilityen_US
dc.subjectFerricen_US
dc.subjectSludgeen_US
dc.subjectAlumen_US
dc.subjectDrinking Wateren_US
dc.titleEffect of Calcium on Arsenic Release From Ferric and Alum Sludges and Lagoonsen_US
dc.typeThesisen_US
dc.contributor.departmentEnvironmental Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineEnvironmental Planningen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-10022001-110024/en_US
dc.contributor.committeecochairEdwards, Marc A.en_US
dc.contributor.committeecochairNovak, John T.en_US
dc.date.sdate2001-10-02en_US
dc.date.rdate2004-10-03
dc.date.adate2001-10-03en_US


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