In order to optimize a corporate cooling water program, real-world plant experience along
with a series of laboratory experimental studies is being used. All aspects of the program are
being considered, including passivation treatments for individual bundles, system pre-film
solutions, and long-term cooling water chemistries. The aim of the optimization plan is to
select the most favorable combination of passivation, pre-film, and cooling water solutions that
provides the most cost-effective protection of the system within defined performance targets
that the vendor must deliver.
This paper will present results of electrochemical laboratory studies designed to provide an
understanding of how each part of the program functions. The focus in this paper will be on
the passivation and protection of brass (Admiralty and Naval) heat exchangers with various
yellow metal inhibitors including benzotriazole (BZT), comparing its performance with a new
proprietary azole inhibitor (PTA) and their compatibility with a phosphate-based cooling water
program.
Keywords: cyclic voltammetry, cooling water, Naval brass, benzotriazole, open circuit potential