In order for a reverse osmosis fresh water generator to be able to overcome the osmotic pressure without damaging the spiral-wound membrane modules, the pressure must be controlled. What is the location of the pressure regulator?

Correct Answer: Option D — Brine outlet from the membrane modules.

Reverse osmosis systems require precise pressure control to overcome osmotic pressure while protecting delicate membranes. The pressure regulator is located on the brine discharge line to maintain the necessary backpressure across the membrane modules, ensuring efficient permeate production without exceeding the structural pressure limits of the membrane elements.