CHEMICAL CLEANING – (PICKLING, PASSIVATION & DEGREASING)
This form of treatment is compatible with alloy steels, carbon steels, and stainless steel requiring low solvent and presents good handling, safety and corrosion characteristics in comparison to hydrochloric acid base & nitric cleaners. It is less aggressive and one of the reasons for its choice is the presence of austenitic materials of construction. Thereafter the cleaning purpose does not need a great handling but the result after cleaning will be more satisfied.
Chemical cleaning basically formed to remove and foreign materials as mineral deposits, scales rust and dirt contamination from the tube or pipes surfaces.
In addition accumulated corrosion products (rust) have to be removed. Since the chemical cleaning process uses water-based solutions, and surface that is cleaned to bare metal will spontaneously rust in the presence of air and water. To minimize this and to allow time for preserving the piping with a positive
nitrogen pressure, a passivation step is included in the procedure.
Corrosion inhibitor i.e ammonium bifloride is added to reduce oxidation and other corrosion.
The final desired condition of the internal surfaces of the piping is the following:
– Free of particulate debris.
– Free of oils and greases
– Generally gray in appearance
Chemical cleaning processes are concentrated for piping, tanks, heat exchanger
Tubing, reactors, process lines, economiser tubes, cracker’s tubes and not limited to offshore related
CPP (Central processing platform), WHP (Well head platform), jackets and even more.
– Minimize the schedule and maximize plant startup
– With optimize flow & temperature the pipe internal cleaning in most effective way
– Mill scales and rust can removed for longer line without dismantle
– To achieve 90% of cleaning acceptance criteria
– Ease the onshore & offshore application with one go cleaning process