Measurement of Dissolved Solids

The measurement of process fluid corrosivity should be supported by measurements of the chemical composition of the different fluid phases present since fluid composition can have an important influence upon corrosion rates, hydrogen damage, stress corrosion cracking, etc. 

The quantitative analysis of non-aqueous samples should be carried out after first ashing the sample in accordance with ASTM D482. 

Samples of liquid for analysis shall be taken from the process stream into clean, stoppered borosrli-cate glass container(s). Reagents should be used so that the ions under test form stable suspensions or complexes. The resulting turbidity or intensity of color change should be determined by photoelectric colorimeter or spectrophotometer and compared to a curve prepared from standard solutions. 

Care shall be taken to ensure that other dissolved ions do not interfere with the formation of the suspension(s) or complex(es), giving rise to spurious results. 

Detailed test methods and procedures are given in the ASTM Pubfication Water and Environmental Technology Section It, Volumes 01 and 02, and API RP45. 

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