8/13/2019 Chilled Water Method Statement, CLT-540

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PROCEDURE FOR INITIAL CLEANING FOR

CHILLED WATER SYSTEM

•  Drain the system and flush with water to remove surplus iron debris.

•  The system shall then be filled with clean fresh water and the applicablequantity of B – 16 Neutral pH cleaner (2 Kgs/ m³) be dosed in quantitiesto achieve homogeneous mixing throughout the entire system whilecirculating.

•  Once the system is dosed and freed of all entrapped air, circulation shall

continue for atleast 48 hours to remove any loose or foreign particles fromthe system. Make sure that there are no dead legs in the circuit that havenot been exposed to the chemical cleaning operation.

•  After 48 hours of circulation with the chemical the entire system shall beblown down with fresh water supply until the entire system is free of allfree standing water (chemically treated.)

•  All system strainers shall be inspected and cleaned as required.

•  Once the bulk solution has been removed from the system, the systemshall be flushed with clean water & drained. This step shall be repeateduntil the following Acceptance level is obtained: The Dissolved Iron shallbe no more than 0.5 mg / l (0.5 ppm) and the TDS shall be equal to thatof the incoming fresh water used for the flushing.

•  With the system full of water matching the above criteria whilecirculating the passivation phase shall commence by injection of the CLT –540 (5 Kgs / m³) & ML – 13G (100 ml / m³) .

•  After and during the passivation process, samples shall be taken and

submitted for approval / acceptance of the passivation phase.

•  The final acceptance of the passivation phase shall be that the Water Birdchemist shall test the circulating water and confirm that the corrosioninhibitor level is within the correct range of 250 ppm as Nitrite & 30-50ppm of Molybdate.