EXPLANATION
The knowledge of the content of salt in crude oil is important in deciding whether or not the crude needs desalting. Excessive salt left in the crude frequently results in higher corrosion in refining units.
TEST SUMMARY
This test method is based on the conductivity of a solution of crude oil in a polar solvent when subjected to an alternating electrical stress. The sample is dissolved in a mixed solvent and placed in a test cell consisting of a beaker and two parallel stainless steel plates. An alternating voltage is passed through the plates and the resulting current flow is shown on a milliammeter. The salt content is obtained by reference to a calibration curve of current versus salt content of known mixtures.
TEST PRECISION
This test method has been extensively tested in a number of laboratories, and found to give results comparable to those from other procedures for determining salt in crude oil.
Where X is the average of two test results.
This test procedure has no bias.