Show simple item record

dc.contributor.authorCubas Suazo, Francisco Joseen_US
dc.date.accessioned2014-03-14T20:46:25Z
dc.date.available2014-03-14T20:46:25Z
dc.date.issued2006-09-19en_US
dc.identifier.otheretd-10062006-002243en_US
dc.identifier.urihttp://hdl.handle.net/10919/35311
dc.description.abstract

The possible effects of changes in the feeding pattern on activated sludge properties related to bioflocculation have been analyzed in lab scale sequencing batch reactors (SBR) in order to determine if these changes in effluent water quality and settling and dewatering properties are significant, so they can be considered in future studies or if they can be recommended as crucial when operating and designing wastewater treatment plants. The activated sludge process is widely used to treat wastewater from both industrial and municipal sources. Biomass from industrial facilities containing high monovalent to divalent ion content usually settles poorly, which leads to low quality effluents that fail to meet environmental requirements. Therefore, the combined effect of feeding pattern plus the addition of sodium to activated sludge reactors was studied in this experiment.

A series of SBRs were operated at different sodium concentrations that ranged from 1.5 - 15 meq/L and different feeding times that ranged from 1 minute to 4 hours. Biomass samples were taken from each reactor to study the settling and dewatering properties and effluent samples were used to analyze the amount of organic matter and exocellular polymeric substances present due to deflocculation. As expected, the changes in feeding strategies affected all of the properties measured. When the feeding time was maintained low (pulse feed) the effluent quality and settling properties were the best. As the feeding time was increased the effluent quality, settling, and dewatering properties increased suggesting that the way in which the reactors were fed affected the overall bioflocculation process. The causes of the high deflocculation observed are not well understood, but data suggest that a microbial community change could have affected exocellular biopolymers which are believed to play an important role on bioflocculation.

This research demonstrates the importance of the interaction between cation content and feeding pattern when operating a wastewater treatment plants and when reporting lab-scaled results related to settling and bioflocculation.

en_US
dc.publisherVirginia Techen_US
dc.relation.haspartMasters_Thesis_Francisco_Cubas.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.subjectdivalent cation bridgingen_US
dc.subjectbiopolymersen_US
dc.subjectfeeding patternen_US
dc.subjectsodiumen_US
dc.subjectbioflocculationen_US
dc.subjectsettlingen_US
dc.subjectcationsen_US
dc.subjectActivated sludgeen_US
dc.subjectsequencing batch reactoren_US
dc.titleEffect of Reactor Feeding Pattern on Performance of an Activated Sludge SBRen_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.contributor.committeechairNovak, John T.en_US
dc.contributor.committeememberBoardman, Gregory D.en_US
dc.contributor.committeememberHiggins, Matthew J.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-10062006-002243/en_US
dc.date.sdate2006-10-06en_US
dc.date.rdate2008-12-06
dc.date.adate2006-12-06en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record