IS PASSIVATION REQUIRED FOR NEW BOILERS
Turn mixer on and add citric acid to the equipment and mix until uniform. Heat the citric solution to 50-72°C. When temperature reaches 50-72°C, allow the solution to contact the surfaces for 10 minutes. Cool citric solution to 35-40°C. Neutralize citric solution to pH = 5 - 6.8 with NaOH . Then empty citric solution to the drain.
Sep 01, 2014 · Once the chemistry in the boiler indicates that the boiler is clean, next is a passivation step. In the case of HCl, passivation is preceded by rinses and neutralization of any remaining acid in
CN104878396A - Boiler pickling and passivating process - Google Patents. The invention relates to the field of boiler pickling, in particular to a passivating process after boiler pickling. The
The operating parameters for the process boiler . packages are as below: Operating pressure -120.5 kg/cm 2, Citric acid cleaning and Passivation is done in one single fill .
Jan 01, 1989 · B) Passivation: Following the process of cleaning and activation of the test pieces, the excess citric acid was neutralized by the careful addition of 1:1 amnonia solution till the pH value of the medium reached 9.2-9.5 (measured with the glass electrodes).
The boiler is filled with a dilute citric acid solution, which dissolves this rust. The pH is raised to an alkaline value using ammonia, and the sequestered iron remains in solution. Dissolution of iron on the surface stops and an oxidizing agent is added.