GROUNDWATER AND LEACHATE: EX-SITU CHEMICAL/PHYSICAL TREATMENT
Ion Exchange
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 (from synthetic organic materials) - contain ionic functional groups to which exchangeable ions are attached. After the resin capacity has been exhausted, resins can be regenerated for re-use.
- Inorganic and natural polymeric materials.
Applicability:
- Used to remove dissolved metals and radio-nuclides from aqueous solutions.
- Note: Other compounds that have been treated include nitrate, ammonia nitrogen, and silicate.
- Ion exchange technology is typically short- to medium-term, dependent on pH and contamination level of inflow and exchange material used.
Limitations:
- Oil and grease in the ground water may clog the exchange resin.
- High suspended solid content may cause resin blinding.
- Oxidants in ground water may damage the ion exchange resin.
- Wastewater is generated during the regeneration step and will require additional treatment and disposal.
Cost:
The cost for a typical ion exchange system ranges from $0.08 to $0.21 per 1,000 litres of fluid treated