WATER TREATMENT TECHNOLOGY

FACT SHEET

Note: Information is from vendor, however specifications may have 

changed. Contact vendor for updates. Water Treatment Catalog and Decision Tool

ION EXCHANGE

Process Description

Ion exchange involves the exchange or replacement of 

dissolved constituents by attachment to an 

electrostatically ion exchange material, which often 

consists of a synthetic resin. Ion exchange is a reversible 

chemical reaction wherein positively or negatively 

charged ions present in the water are replaced by 

similarly charged ions present within the resin. When the 

replacement ions on the resin are exhausted, the resin is 

recharged with more replacement Ions. The process relies 

on the fact that water solutions must be electrically 

neutral. Therefore, ions in the resin bed are exchanged 

with ions of similar charge in the water and as result of 

the exchange process; no reduction in ions is obtained.

Technical Capabilities

The process of ion exchange has historically been used to 

remove hardness ions such as calcium and magnesium by 

replacing them with sodium and chloride ions. In the case 

of oil and gas produced water, ion exchange is typically 

used to preferentially remove sodium, reducing the 

sodicity of the water. As produced water passes through 

the system, sodium ions are removed from the water and 

replace hydrogen ions on the resin's exchange sites.

However, ion exchange is limited to removing 

constituents in waters with TDS levels below 

approximately 5,000 mg/L, with a generated waste 

stream of approximately 1 to 5 percent of the input

water.

In the shale gas industry, ion exchange is applicable as a 

pretreatment method to remove other water constituents 

such as, heavy metals (i.e., barium, iron, strontium), 

nitrates, alkalinity, anionic complexes of uranium or 

utilized as a polishing treatment.

Technical Limitations

As stated, ion exchange is limited to removing 

constituents in waters with TDS concentrations below

approximately 5,000 mg/L. 

Ion exchange requires pretreatment (deoiling, 

precipitation softening, TSS, etc.) to avoid resin fouling

and the process cannot remove nonionic dissolved species 

or microbes.

Operation and management considerations for IX include 

occasional disinfection of IX resin with NaOCl or H2O2. 

Careful management of the feed stream is also necessary 

to ensure that fouling agents such as suspended solids, 

scale forming materials (e.g., CaSO4), and oxidized 

metal are not present in the feed water.

Costs

The process of ion exchange has minimal operational energy 

demands and typically only requires electricity to operate 

small pumps for pumping fluids under low hydraulic 

pressure. In addition, the capital cost of ion exchange 

equipment is less than for reverse osmosis or distillation 

equipment assuming TDS levels are at appropriate levels. 

Treatment CompanyTreatment Company

Ion 

Exchange

Shale Gas Basin

Marcellus

Barnett

Haynesville

Fayetteville

Woodford

Ion exchange has limited applicability in the Shale 

Gas industry as a desalination treatment 

technology. It is suitable as a pre-treatment or 

polishing technology that is integrated into an 

overall treatment process.

KEY CONSIDERATIONS

 Limited applicability since the technology is not 

capable of removing TDS levels above 

approximately 5,000 mg/L.

 Applicable as a pretreatment method to remove 

water constituents/parameters such as, heavy 

metals, alkalinity or used as a polishing 

treatment.

 The cost for a typical ion exchange system ranges 

from 0.08 to $0.11 at 220 gpm or $0.04 to 

$0.07 at 880 gpm.
WATER TREATMENT TECHNOLOGY

FACT SHEET

Note: Information is from vendor, however specifications may have 

changed. Contact vendor for updates. Water Treatment Catalog and Decision Tool

The cost for a typical ion exchange system ranges from 

approximately $0.08 to $0.11 at 220 gpm or $0.04 to 

$0.07 at 880 gpm. However, studies conducted by EMIT 

Water Discharge Technology, LLC in the Powder River 

Basin via the Higgins Loop, indicated treatment costs

ranged from $0.05 to $0.20 per barrel of treated water, 

depending on the influent composition. 

References

National Energy Technology Laboratory (NETL). 

Produced Water Management Information System 

(PWMIS). Produced Water Management DescriptionsIon Exchnage. 

Colorado School of Mines. Produced Water Treatment 

and Beneficial Use Information Center. Treatment 

Options. Ion Exchnage.

Drainage Water Treatment Technical Committee. 1999. 

Drainage Water Treatment. Final Report. The San 

Joaquin Valley Drainage Implementation Program and 

The University of California Salinity/Drainage Program.

ALL Consulting. 2003. Handbook on Coal Bed Methane 

Produced Water: Management and Beneficial Use 

Alternatives. Prepared For: Ground Water Protection 

Research Foundation U.S. Department of Energy 

National Petroleum Technology Office Bureau of Land 

Management.

Department of the Army. 1986. Technical Manual, 

Water Desalination. TM 5-813-8.

ALL Consulting and Interstate Oil and Gas Compact 

Commission. 2006. A Guide to Practical Management of 

Produced Water from Onshore Oil and Gas Operations 

in the United States. Prepared for the U.S. Department 

of Energy National Petroleum Technology Office.

Personal Conversation between Nathan Alleman and Dan 

Silverstein of Applied Membranes. February 4, 2009.

Dow Chemical Company. FILMTEC Membranes. 

Oxidation-Filtration. Accessed at: www.dow.com.

Desalination Techniques. Universities Council on Water 

Resources.

Burnett, Dave., Rich Haut, and Tom Williams. 

Environmentally Friendly Drilling Systems Background & 

Current Programs. Global Petroleum Research Institute.