Matches in SemOpenAlex for { <https://semopenalex.org/work/W334161874> ?p ?o ?g. }
Showing items 1 to 75 of
75
with 100 items per page.
- W334161874 abstract "Author(s): Wang, Yue | Advisor(s): Matsumoto, Mark R. | Abstract: Perchlorate (ClO4-) has gained attention recently due to its interference with thyroid gland function. In infants and unborn children, inadequate thyroid hormone production can cause mental retardation and thyroid tumors. Since new perchlorate standards will be proposed in 2013, and if a stricter standard is imposed, cost effective technologies will be in high demand. The overall objective of this research was to evaluate two perchlorate bioremediation strategies using indigenous soil bacteria: 1) an autotrophic strategy using zero-valent iron (ZVI) to generate hydrogen as the electron donor and alkalinity in the form of (bi)carbonate as the carbon source for cell growth and maintenance and 2) a heterotrophic strategy using organic substrates as the electron donor and the carbon source for cell growth and maintenance. The first strategy was evaluated on perchlorate-contaminated groundwater from West Valley Water District Well #2 located in Rialto, CA (Chapter III). A mobile treatment system consisting of a water holding tank, a ZVI packed bed and two parallel sand filters was placed at the site. In the first three months, the system experienced excellent performance, as measured by the tested parameters meeting the California drinking water standards. The effluent concentration of perchlorate was non-detectable (below 4 µg/L), nitrate effluent concentration was less than 0.01 mg/L as N, effluent iron ranged from 0 to 0.05 mg/L. Coliforms, fecal coliforms and E. coli in the reactor effluent were below the detection limit of 2 MPN/100mL. However, significant loss of perchlorate performance was observed after 3 months operation. The reason was attributed to the reduction of hydraulic conductivity and flow channeling. A laboratory column experiment was conducted to investigate the hydraulic condition change in the ZVI beds (Chapter IV). Effects of flow rate and (bi)carbonate on hydraulic condition were evaluated by performing hydraulic conductivity tests, SEM examination, and tracer tests. The results indicated that the decrease of hydraulic conductivity was more pronounced in the low flow reactors than in the higher flow reactors. This result appeared to contradict the hypothesis that increasing the flow rate will accelerate the hydraulic conductivity reduction. (Bi)carbonate was determined to be the primary cause of the hydraulic conductivity reduction. The decrease in hydraulic conductivity was most severe in the segment receiving the higher concentration of NaHCO3. Hydraulic conductivity decreased from 10-2.73 cm/s to 10 -7.33 cm/s after constantly feeding 24 mM of NaHCO3 for 41 days. The reduction of hydraulic conductivity was caused by the formation of mineral precipitates. Because of the lack of long-term perchlorate reduction in the autotrophic ZVI-based system, an alternative strategy that utilized organics as both the electron donor and carbon growth source was tested for perchlorate bioremediation (Chapter V). Laboratory microcosm and column tests were employed to assess the effectiveness of selected organic substrates on reducing perchlorate from two different locations of a real perchlorate-contaminated site. One location (source area) had 70 mg/L of perchlorate in groundwater, and another one (plume edge, referred to biobarrier) had 500 µg/L of perchlorate. The effect of adding nutrients was also examined. For the high concentration source area treatment, emulsified oil substrate (EOS) and glycerin were determined to be the most effective organics from the microcosm testing. Hence, they were selected for column testing. The results revealed that amending soil with EOS had significant advantages over using glycerin as a soil amendment. After a single injection of EOS, perchlorate can be reduced to less than 4 µg/L for 4 months. Perchlorate reduction was not initiated in glycerin-amended soil. Glycerin had to be constantly added into the influent to treat perchlorate to non-detectable level. For the low concentration biobarrier treatment, compost/mulch, EOS, and EHC (a combination of carbon plant-based carbon source and zero-valent iron) had similar perchlorate removal rates in microcosm tests. EOS appeared to have greater longevity than EHC in the column tests. The addition of nutrients had minor benefit on both sites treatments. Comparing the two strategies, using organic substrate was more feasible for perchlorate bioremediation in terms of overall performance and longevity." @default.
- W334161874 created "2016-06-24" @default.
- W334161874 creator A5033632697 @default.
- W334161874 date "2012-01-01" @default.
- W334161874 modified "2023-09-26" @default.
- W334161874 title "Different Strategies for Biological Remediation of Perchlorate Contaminated Groundwater" @default.
- W334161874 hasPublicationYear "2012" @default.
- W334161874 type Work @default.
- W334161874 sameAs 334161874 @default.
- W334161874 citedByCount "0" @default.
- W334161874 crossrefType "journal-article" @default.
- W334161874 hasAuthorship W334161874A5033632697 @default.
- W334161874 hasConcept C107872376 @default.
- W334161874 hasConcept C112570922 @default.
- W334161874 hasConcept C127413603 @default.
- W334161874 hasConcept C145148216 @default.
- W334161874 hasConcept C147455438 @default.
- W334161874 hasConcept C178790620 @default.
- W334161874 hasConcept C185592680 @default.
- W334161874 hasConcept C187320778 @default.
- W334161874 hasConcept C18903297 @default.
- W334161874 hasConcept C2124996 @default.
- W334161874 hasConcept C2776384668 @default.
- W334161874 hasConcept C2780709120 @default.
- W334161874 hasConcept C39432304 @default.
- W334161874 hasConcept C522964758 @default.
- W334161874 hasConcept C548081761 @default.
- W334161874 hasConcept C76177295 @default.
- W334161874 hasConcept C86803240 @default.
- W334161874 hasConcept C87717796 @default.
- W334161874 hasConceptScore W334161874C107872376 @default.
- W334161874 hasConceptScore W334161874C112570922 @default.
- W334161874 hasConceptScore W334161874C127413603 @default.
- W334161874 hasConceptScore W334161874C145148216 @default.
- W334161874 hasConceptScore W334161874C147455438 @default.
- W334161874 hasConceptScore W334161874C178790620 @default.
- W334161874 hasConceptScore W334161874C185592680 @default.
- W334161874 hasConceptScore W334161874C187320778 @default.
- W334161874 hasConceptScore W334161874C18903297 @default.
- W334161874 hasConceptScore W334161874C2124996 @default.
- W334161874 hasConceptScore W334161874C2776384668 @default.
- W334161874 hasConceptScore W334161874C2780709120 @default.
- W334161874 hasConceptScore W334161874C39432304 @default.
- W334161874 hasConceptScore W334161874C522964758 @default.
- W334161874 hasConceptScore W334161874C548081761 @default.
- W334161874 hasConceptScore W334161874C76177295 @default.
- W334161874 hasConceptScore W334161874C86803240 @default.
- W334161874 hasConceptScore W334161874C87717796 @default.
- W334161874 hasLocation W3341618741 @default.
- W334161874 hasOpenAccess W334161874 @default.
- W334161874 hasPrimaryLocation W3341618741 @default.
- W334161874 hasRelatedWork W129791637 @default.
- W334161874 hasRelatedWork W1978809209 @default.
- W334161874 hasRelatedWork W2058201586 @default.
- W334161874 hasRelatedWork W2060328804 @default.
- W334161874 hasRelatedWork W2103990951 @default.
- W334161874 hasRelatedWork W2112120105 @default.
- W334161874 hasRelatedWork W2119042988 @default.
- W334161874 hasRelatedWork W2523418150 @default.
- W334161874 hasRelatedWork W2536006326 @default.
- W334161874 hasRelatedWork W2738783353 @default.
- W334161874 hasRelatedWork W2749779747 @default.
- W334161874 hasRelatedWork W2920659234 @default.
- W334161874 hasRelatedWork W3038526378 @default.
- W334161874 hasRelatedWork W3112109154 @default.
- W334161874 hasRelatedWork W3158373377 @default.
- W334161874 hasRelatedWork W3162995739 @default.
- W334161874 hasRelatedWork W3168582215 @default.
- W334161874 hasRelatedWork W3199606172 @default.
- W334161874 hasRelatedWork W79687100 @default.
- W334161874 hasRelatedWork W2590782332 @default.
- W334161874 isParatext "false" @default.
- W334161874 isRetracted "false" @default.
- W334161874 magId "334161874" @default.
- W334161874 workType "article" @default.