Calcium Carbonate Formation in Water Distribution Systems and Autogenous Repair of Leaks by Inert Particle Clogging

dc.contributor.authorRichards, Colin Scotten
dc.contributor.committeechairEdwards, Marc A.en
dc.contributor.committeememberWang, Feien
dc.contributor.committeememberSinha, Sunil Kumaren
dc.contributor.departmentCivil and Environmental Engineeringen
dc.date.accessioned2017-12-13T07:00:24Zen
dc.date.available2017-12-13T07:00:24Zen
dc.date.issued2016-06-20en
dc.description.abstractThe formation of calcium carbonate (CaCO3) (i.e. scale) in potable water systems has long been a concern in water treatment and distribution. A literature review reveals that CaCO3 scaling issues are re-emerging due to climate change, temperature increases in hot water systems and lower use of scaling and corrosion inhibitors. Moreover, we have gathered insights that suggest CaCO3 coatings can be beneficial and stop pipeline leaks via self-repair or clogging. Ironically, the actions we are taking to increase the lifespan of distribution systems (i.e. adding corrosion inhibitors) might have worsened leaks and pipe lifespans due to interference with self-repair. The increasing occurrence of scaling coupled with gaps in knowledge over CaCO3 formation in water systems make revisiting this topic timely. The concept of autogenous repair by clogging with inert particles was examined using silica and alumina. Small 250 m diameter pinhole leaks were simulated in bench-scale water recirculation systems. Silica and alumina particles were added to solutions ranging from high to low ionic strength to determine the impact of water quality on leak repair. Size distribution and zeta potential of the particles were measured. Silica particles were practically unchanged by the different solution chemistries while the size and zeta potential of alumina particles varied. The rate of clogging with silica particles was not impacted by water chemistry. Alumina particles with a positive charge clogged 100% of the leaks while negatively charged alumina could not clog 100%. Very small alumina particles (4.1 m) stayed suspended but were unable to clog leaks.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.othervt_gsexam:8206en
dc.identifier.urihttp://hdl.handle.net/10919/81180en
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectCalcium carbonateen
dc.subjectdistribution systemen
dc.subjectprecipitationen
dc.subjectparticle cloggingen
dc.subjectautogenous repairen
dc.titleCalcium Carbonate Formation in Water Distribution Systems and Autogenous Repair of Leaks by Inert Particle Cloggingen
dc.typeThesisen
thesis.degree.disciplineEnvironmental Planningen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Richards_CS_T_2016.pdf
Size:
3.67 MB
Format:
Adobe Portable Document Format

Collections