| Description:
Figure 4-48:
Typical Ion Exchange and Adsorption Equipment Diagram
Ion exchange removes ions from the aqueous phase by the
exchange of cations or anions between the contaminants and the exchange medium. Ion
exchange materials may consist of resins made from synthetic organic materials that
contain ionic functional groups to which exchangeable ions are attached. They also may be
inorganic and natural polymeric materials. After the resin capacity has been exhausted,
resins can be regenerated for re-use.The duration of ion exchange technology is
typically short- to medium-term depending on the factors discussed in Data Needs.
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| Synonyms:
NA
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| Applicability:
Ion exchange can remove dissolved metals and radionuclides from aqueous
solutions. Other compounds that have been treated include nitrate, ammonia nitrogen, and
silicate.
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| Limitations:
Factors that may affect the applicability and effectiveness of this
process include:
- Oil and grease in the ground water may clog the exchange resin.
- Suspended solids content greater than 10 ppm may cause resin blinding.
- The pH of the influent water may affect the ion exchange resin selection.
- Oxidants in ground water may damage the ion exchange resin.
- Wastewater is generated during the regeneration step and will require additional
treatment and disposal.
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| Data Needs:
A detailed discussion of these data elements is provided in Subsection 2.2.2 (Data Requirements for Ground Water,
Surface Water, and Leachate).Factors affecting the design of an ion exchange system
include the presence of oil and grease, contaminant concentration, exchange capacity of
the resin, suspended solids, metals, oxidant content, inorganic ions in ground water; and
pH of the ground water.
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| Performance Data:
DOE has developed compact processing units (CPUs), or "modular waste
treatment units," which are relatively small mobile equipment modules. They perform
unit chemical process operations. The CPUs allow rapid deployment of technologies for the
treatment of radioactive wastes in underground storage tanks. The modules would be
manufactured off-site by commercial vendors and moved into place using trucks or special
transports. The concept of having standardized modules is based on the notion that various
radioactive waste treatment subsystems could be standardized to match the CPU hardware
package, leading to more rapid, cost-effective deployment. The cost benefits are realized
even when multiple units are deployed to achieve greater processing rates. The modular
design concept will also allow for reuse of CPU components for different unit processes or
process deployments.The ion-exchange CPU will pump undiluted liquid tank waste from an
underground storage tank or receive liquid waste from a waste retrieval system for
treatment. DOE Northwest Laboratories developed the CPU concept in FY91. Development of a
cesium ion-exchange CPU technology is scheduled for 1996. A radioactive waste treatment
demonstration is scheduled for FY97.
Another DOE technology, the resorcinol-formaldehyde ion exchange (ReFIX) resin, is
being developed for prototype demonstration at the Hanford site in FY97. ReFIX resin is
applicable to high-level wastestreams containing cesium-supernate salt solutions.
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| Cost:
The cost for a typical ion exchange system ranges from $0.08 to $0.21 per
1,000 liters ($0.30 to $0.80 per 1,000 gallons) treated. Key cost factors include:
- Pretreatment requirements.
- Discharge requirements and resin utilization.
- Regenerant used and efficiency.
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| References:
Innovative Remediation
Technologies: Field Scale Demonstration Project in North America, 2nd
Edition
Abstracts
of Remediation Case Studies, Volume 4, June 2000, EPA
542-R-00-006
Guide to Documenting and Managing
Cost and Performance Information for Remediation Projects - Revised Version,
October, 1998, EPA 542-B-98-007
California Base Closure Environmental Committee (CBCEC), 1994. Treatment
Technologies Applications Matrix for Base Closure Activities, Revision 1,
Technology Matching Process Action Team, November, 1994.DOE, 1993. Technology
Name: Cesium Removal by Compact Processing Units for Radioactive Waste Treatment,
Technology Information Profile (Rev. 2) for ProTech, DOE ProTech Database, TTP Reference
No.: RL-321221.
DOE, 1993. Technology Name: Resorcinol-Formaldehyde Ion Exchange Resin for
Elutable Ion Exchange in the Compact Portable Units (CPUs) Proposed at Hanford,
Technology Information Profile (Rev. 2) for ProTech, DOE ProTech Database, TTP Reference
No.: SR-1320-02.
DOE, 1994. Technology Catalogue, First Edition. February.
EPA, 1990. Innovative and Alternative Technology Assessment Manual,
EPA, Office of Water Program Operations, EPA/430/9-78/009.
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Site Information:
Points of Contact:
General FRTR Agency Contacts
Technology Specific Web Sites:
Government Web Sites
Non Government Web Sites
Vendor Information:
A list of vendors offering
Ex Situ Physical/Chemical Water Treatment is available from EPA
REACH IT which combines information from three established EPA databases,
the Vendor Information System for Innovative Treatment Technologies (VISITT),
the Vendor Field Analytical and Characterization Technologies System (Vendor
FACTS), and the Innovative Treatment Technologies (ITT), to give users access to
comprehensive information about treatment and characterization technologies and
their applications.
Government Disclaimer
Health and Safety:
Hazard Analysis
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