In the design and operation of reverse osmosis and nanofiltration installations, it is important to predict the CaSO₄, SrSO₄, and BaSO₄ scaling properties of the concentrate stream. Because of the increase in total dissolved solids and the increase in concentration of the scaling salts, the scaling properties of the concentrate stream will be quite different from those of the feed solution. This practice permits the calculation of the scaling potential for the concentrate stream from the feed water analyses and the reverse osmosis or nanofiltration operating parameters.

Scaling by CaSO₄, SrSO₄, and BaSO₄ will adversely affect the reverse osmosis or nanofiltration performance. This practice gives various procedures for the prevention of scaling.

1. Scope

1.1 This practice covers the calculation and adjustment of calcium, strontium, and barium sulfates for the concentrate stream of a reverse osmosis or nanofiltration system. The calculations are used to determine the need for scale control in the operation and design of reverse osmosis and nanofiltration installations. This practice is applicable for all types of reverse osmosis devices (tubular, spiral wound, and hollow fiber) and nanofiltration devices.

1.2 This practice is applicable to both brackish waters and seawaters.

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

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

D511 Test Methods for Calcium and Magnesium In Water

D516 Test Method for Sulfate Ion in Water

D1129 Terminology Relating to Water

D3352 Test Method for Strontium Ion in Brackish Water, Seawater, and Brines

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

D4195 Guide for Water Analysis for Reverse Osmosis and Nanofiltration Application

D4382 Test Method for Barium in Water, Atomic Absorption Spectrophotometry, Graphite Furnace

D6161 Terminology Used for Microfiltration, Ultrafiltration, Nanofiltration and Reverse Osmosis Membrane Processes

Keywords

barium; calcium; membrane fouling; membrane scaling; nanofiltration; reverse osmosis; strontium; sulfate scaling; Sulfate scaling salts; Water content; Barium sulfate (BaSO4); Brackish water/brines; Concentration (of elements); Nanofiltration (NF) materials/applications; Reverse osmosis (RO) installations; Saltwater; Scale control; Seawater (natural/synthetic); Strontium sulfate (SrSO4);

ICS Code

ICS Number Code 71.120.99 (Other equipment for the chemical industry)

Citing ASTM Standards

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