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Title: Electroosmotic decontamination of concrete

Abstract

A method is described for the electroosmotic decontamination of concrete surfaces, in which an electrical field is used to induce migration of ionic contaminants from porous concrete into an electrolyte solution that may be disposed of as a low-level liquid radioactive waste (LLRW); alternately, the contaminants from the solution can be sorbed onto anion exchange media in order to prevent contaminant buildup in the solution and to minimize the amount of LLRW generated. We have confirmed the removal of uranium (and infer the removal of {sup 99}Tc) from previously contaminated concrete surfaces. In a typical experimental configuration, a stainless steel mesh is placed in an electrolyte solution contained within a diked cell to serve as the negative electrode (cathode) and contaminant collection medium, respectively, and an existing metal penetration (e.g., piping, conduit, or rebar reinforcement within the concrete surface) serves as the positive electrode (anode) to complete the cell. Typically we have achieved 70 to >90% reductions in surface activity by applying <400 V and <1 A for 1--3 h (energy consumption of 0.4--12 kWh/ft{sup 2}).

Authors:
; ; ;  [1]; ;  [2]
+ Show Author Affiliations
  1. Oak Ridge K-25 Site, TN (United States)
  2. Oak Ridge National Lab., TN (United States)
Publication Date:
Research Org.:
Oak Ridge K-25 Site, TN (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10141134
Report Number(s):
K/TCD-1054
ON: DE93010258; TRN: 93:015178
DOE Contract Number:
AC05-84OT21400
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Mar 1993
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CONCRETES; DECONTAMINATION; ELECTRODES; ELECTRIC FIELDS; ELECTRODYNAMICS; LOW-LEVEL RADIOACTIVE WASTES; TECHNETIUM 99; URANIUM; ORGDP; 052001; 400400; WASTE PROCESSING; ELECTROCHEMISTRY

Citation Formats

Bostick, W.D., Bush, S.A., Marsh, G.C., Henson, H.M., Box, W.D., and Morgan, I.L. Electroosmotic decontamination of concrete. United States: N. p., 1993. Web. doi:10.2172/10141134.
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Bostick, W.D., Bush, S.A., Marsh, G.C., Henson, H.M., Box, W.D., & Morgan, I.L. Electroosmotic decontamination of concrete. United States. doi:10.2172/10141134.
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Bostick, W.D., Bush, S.A., Marsh, G.C., Henson, H.M., Box, W.D., and Morgan, I.L. Mon . "Electroosmotic decontamination of concrete". United States. doi:10.2172/10141134. https://www.osti.gov/servlets/purl/10141134.
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@article{osti_10141134,
title = {Electroosmotic decontamination of concrete},
author = {Bostick, W.D. and Bush, S.A. and Marsh, G.C. and Henson, H.M. and Box, W.D. and Morgan, I.L.},
abstractNote = {A method is described for the electroosmotic decontamination of concrete surfaces, in which an electrical field is used to induce migration of ionic contaminants from porous concrete into an electrolyte solution that may be disposed of as a low-level liquid radioactive waste (LLRW); alternately, the contaminants from the solution can be sorbed onto anion exchange media in order to prevent contaminant buildup in the solution and to minimize the amount of LLRW generated. We have confirmed the removal of uranium (and infer the removal of {sup 99}Tc) from previously contaminated concrete surfaces. In a typical experimental configuration, a stainless steel mesh is placed in an electrolyte solution contained within a diked cell to serve as the negative electrode (cathode) and contaminant collection medium, respectively, and an existing metal penetration (e.g., piping, conduit, or rebar reinforcement within the concrete surface) serves as the positive electrode (anode) to complete the cell. Typically we have achieved 70 to >90% reductions in surface activity by applying <400 V and <1 A for 1--3 h (energy consumption of 0.4--12 kWh/ft{sup 2}).},
doi = {10.2172/10141134},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Mar 01 00:00:00 EST 1993},
month = {Mon Mar 01 00:00:00 EST 1993}
}
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Technical Report:
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DOI:  10.2172/10141134
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