Industrial Water Analysis

How is water used in the refinery process?

The majority of water used in the refinery industry is for cooling. In the distillation process, coolers condense the vapors into liquid products, which allow them to be easily handled. This water is typically reused. The second highest use for water is the makeup water for boiler and feed. Steam used for stripping, steam distillation, and vacuum distillation becomes heavily contaminated when it contacts products. This water cannot be reused as boiler feed, so new water is required to make up water loss. On the other hand, condensate from the condensers is generally reused as boiler feed or as makeup water for other needs. A small portion of water is used for the plant operational processes, sanitary purposes, and other services.


Why is industrial water testing necessary?

Testing industrial water

In general, different refinery processes require different qualities of water:

  • Cooling water generally needs to be able to resist corrosion and reduce organic slimes and sediment formation.
  • Circulating water systems often have fouling and corrosion problems without chemical treatment. Boilers and cooling water, for example, are treated with amines to neutralize the acidic build-up that may damage the facility.
  • Boiler feed water makeup requires higher quality water to prevent excessive corrosion and scale formation. Although the modern system may not even need annual cleaning, it is important to check impurities in boiler water to make sure it delivers satisfactory results.

As in other power plants, refinery power plants need to monitor the ionic impurities in various water streams, such as boiler water, cooling water, feed water, and condensate water. By understanding the level of contamination, facility operators can take actions to reduce the damage from corrosion, deposition, and scaling. Industrial water testing is, therefore, essential for quality control and process optimization in the refinery.


Industrial water testing

Industrial water testing

Monitoring ionic impurity in various water streams can include:

  • Trace sodium and transition metals
  • Trace anions in high purity water
  • Chloride and sulfate

These anions and cations can be analyzed by modern ion chromatography (IC) techniques, with solutions to several challenges including:

  • Detection of trace level of analyte (such as sodium) in a background of high ionic-strength matrices (amines). Thanks to the development of high capacity cation-exchange columns, this challenge has been minimized.
  • Preconcentration of a sample when trace anions (low µg/L) are quantified. Preconcentration requires extra hardware such as a concentration column and pump, and takes extra time. Using gradient separation, trace anions can be analyzed with direct injection.