Objective 10: Reverse Osmosis

Question 1

Osmosis

Answer 1

The truism that when 2 solutions having different concentrations of dissolved solids are separated by a semi-permeable membrane, the solute (water) from the less concentrated solution will diffuse through the membrane into the more concentrated solution.

Question 2

Reverse Osmosis

Answer 2

Upon application of high pressure to the more concentrated solution, the water will diffuse through the membrane to the less concentrated solution.

Question 3

Reverse Osmosis System

Answer 3

Water with a high concentration of suspended solids is pressurized and forced through a number of membrane modules, connected in parallel. The suspended solids are left behind and the water on the low pressure side will have a high purity.

Question 4

How effective can Reverse Osmosis be?

Answer 4

It can remove 99% of the dissolved salts from water

Question 5

What can happen to a Reverse Osmosis System over time?

Answer 5

Suspended solids, scale, and micro-organisms may accumulate on the membranes and reduce the water output or increase the salt leakage through the membranes.

Question 6

What is the remedy to a Reverse Osmosis System fouling?

Answer 6

The membranes may be removed from service and cleaned with available cleaners that are specifically suited to the membrane material and the type of fouling.