Normalized salt rejection membrane scaling

Performance of an RO system, specifically the permeate flow rate, salt rejection and pressure drop, is a function of membrane fouling, scaling, and degradation, as previously discussed (See Chapter 11.3). This chapter covers the detailed effects of membrane fouling, scaling, and degradation have on normalized product flow, normalized salt rejection, and pressure drop. 

Membrane scaling and degradation can lead to a loss in normalized salt rejection as can breaches O-rings and permeate tube. 

Membranes are typically not cleaned due to a drop in salt rejection. This is because in most instances, there is a mechanical explanation for the drop in salt rejection (see Chapter 12.2.2). However, in the case where membrane scaling is responsible for a drop in salt rejection, normalized permeate flow is generally the first indicator of this phenomenon (see Chapter 11.3.1.2)... 

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