Significance and Use

CEDI devices can be used to produce deionized water from feeds of pretreated water. This test method permits the measurement of key performance capabilities of CEDI devices using a standard set of conditions. The data obtained can be analyzed to provide information on whether changes may have occurred in operating characteristics of the device independently of any variability in feed water characteristics or operating conditions. Under specific circumstances, the method may also provide sufficient information for plant design.

1. Scope

1.1 This test method covers the determination of the operating characteristics of continuous electrodeionization (CEDI) devices, indicative of deionization performance when a device is applied to production of highly deionized water from the product water of a reverse osmosis system. This test method is a procedure applicable to feed waters containing carbonic acid and/or dissolved silica and other solutes, with a conductivity range of approximately 2 to 100 microsiemens-cm ^-1 .

1.2 This test method covers the determination of operating characteristics under standard test conditions of CEDI devices where the electrically active transfer media therein is predominantly regenerated.

1.3 The test method is not necessarily indicative of:

1.3.1 Long term performance on feed waters containing foulants and/or sparingly soluble solutes;

1.3.2 Performance on feeds of brackish water, sea water, or other high salinity feeds;

1.3.3 Performance on synthetic industrial feed solutions, pharmaceuticals, or process solutions of foods and beverages; or,

1.3.4 Performance on feed waters less than 2 ? S/cm, particularly performance relating to organic solutes, colloidal or particulate matter, or biological or microbial matter.

1.4 The test method, subject to the limitations described, can be applied as either an aid to predict expected deionization performance for a given feed water quality, or as a method to determine whether performance of a given device has changed over some period of time. It is ultimately, however, the user's responsibility to ensure the validity of the test method for their specific applications.

1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.6 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D513 Test Methods for Total and Dissolved Carbon Dioxide in Water

D859 Test Method for Silica in Water

D1125 Test Methods for Electrical Conductivity and Resistivity of Water

D1129 Terminology Relating to Water

D1293 Test Methods for pH of Water

D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water

D4194 Test Methods for Operating Characteristics of Reverse Osmosis and Nanofiltration Devices

Keywords

continuous electrodeionization; deionization; electrical current efficiency; electrical resistance; electrodeionization; electroregeneration; high purity water; pressure differential; Continuous electrodeionization (CEDI) devices; Deionization; Electrical current efficiency; Electrical resistance/resistivity; Electrodeionization; Electroregeneration; Instrumental measurement--water; Osmosis devices (reverse); Performance--water analysis equipment; Pressure differential; Water (high-purity);

ICS Code

ICS Number Code 71.040.50 (Physicochemical methods of analysis)

DOI: 10.1520/D6807-02R09

ASTM International is a member of CrossRef.

ASTM D6807