Numerical Model for Biological Fluidized-Bed Reactor Treatment of Perchlorate-Contaminated Groundwater
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- 作者：Perry L. McCarty and Travis E. Meyer
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：February 1, 2005
- 年：2005
- 卷：39
- 期：3
- 页码：850 - 858
- 全文大小：313K
- 年卷期：v.39,no.3(February 1, 2005)
- ISSN：1520-5851
文摘
Biological fluidized-bed reactor (BFBR) treatment with 1.3mm granular activated carbon as support medium isbeing used for removal of 2.6 mg/L perchlorate fromcontaminated groundwater in California. The Californiadrinking-water action level of 4 
g/L for perchlorate requires99.9% perchlorate removal. Sufficient ethanol, the electrondonor, is added to remove oxygen and nitrate as wellas perchlorate, as all three serve as electron acceptors,but with biological preference for oxygen and nitrate.A numerical BFBR model based upon basic physical, chemical,and biological processes including reaction stoichiometry,biofilm kinetics, and sequential electron acceptor usagewas developed and evaluated with the full-scale treatmentresults. A key fitting parameter was bacterial detachmentrate, which impacts reaction stoichiometry. For bestmodel fit this was found to vary between 0.062 and 0.31d-1, with an average of 0.22 d-1. The model indicates thatGAC particle size, reactor diameter, and perchlorateconcentration affect BFBR performance. While empty-beddetention time might be decreased somewhat below 10min by an increase in either GAC particle size or reactordiameter, the current design provides a good factor of safetyin operation. With a 10 min detention time, the effluentgoal of 4 g/L should be achievable even with influentperchlorate concentration as high as 10 mg/L.
g/L for perchlorate requires99.9% perchlorate removal. Sufficient ethanol, the electrondonor, is added to remove oxygen and nitrate as wellas perchlorate, as all three serve as electron acceptors,but with biological preference for oxygen and nitrate.A numerical BFBR model based upon basic physical, chemical,and biological processes including reaction stoichiometry,biofilm kinetics, and sequential electron acceptor usagewas developed and evaluated with the full-scale treatmentresults. A key fitting parameter was bacterial detachmentrate, which impacts reaction stoichiometry. For bestmodel fit this was found to vary between 0.062 and 0.31d-1, with an average of 0.22 d-1. The model indicates thatGAC particle size, reactor diameter, and perchlorateconcentration affect BFBR performance. While empty-beddetention time might be decreased somewhat below 10min by an increase in either GAC particle size or reactordiameter, the current design provides a good factor of safetyin operation. With a 10 min detention time, the effluentgoal of 4 g/L should be achievable even with influentperchlorate concentration as high as 10 mg/L.