Return to Service Flush

The on-line flush can also be programmed into the PLC and occurs automatically when the RO skid is brought back on line. Most RO systems are equipped with this feature. 

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The on-line flush takes place when the RO skid is returned to service. The objective of the flush is to remove particulates and salts that have settled on the membrane surface while the skid was off line as well as to bring down the concentration of the RO permeate. Figure 13.2 shows the concentration of the RO permeate as a function of flush... 

Crop. To cut replacement refractory bricks roughly flush with surrounding worn lining bricks, to equalise behaviour when returned to service. 

When the RO system is being brought back on line, it should be flushed with low-pressure feed water for about an hour. Any permeate generated should be sent to drain. The permeate should be checked for residual biocide prior to returning the RO unit to service. If any is present, flushing should continue. 

Flush inlet headers, laterals, and return lines Drain to prevent freezing Clean tower basin Adjust tower fans Service Air... 

The inside surface should be 316L electro-polished (Ra < 0.8 p) the tank must be totally drainable. Storage tanks must be equipped with a spray ball on the circulation return line to sanitize all internal parts of the tank and to assure that the tank interior surfaces above the water level are continuously flushed. Tanks must be equipped with a vent hlter (0.2 pm hydrophobic) installed in such a way as to prevent condensate from being trapped. The technical services manager and QA manager must approve the model. 

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