Reverse Osmosis (RO) is a powerful technology widely used for purifying water in various applications, from residential drinking water systems to industrial processes. In this blog post, we’ll delve into the essential calculations and terminology associated with RO systems.
How Reverse Osmosis Works
Reverse Osmosis operates on the principle of selectively allowing water molecules to pass through a semi-permeable membrane while rejecting contaminants. This process involves applying pressure to the feed water (the water to be treated), forcing it through the membrane. The result is two streams: purified water (permeate) and concentrated contaminants (brine or concentrate).
Key Terminology
- RO Feed Water: The untreated water that enters the RO system for purification.
- RO Permeate: The purified water that passes through the membrane and is collected for use.
- RO Concentrate (or Brine): The stream containing the rejected contaminants, which exits the RO system.
- RO Recovery : The percentage of feed water that becomes permeate. It’s calculated as:
$$ \text{Recovery (%)} = \frac{Q_\text{permeate}}{Q_\text{feed}} \times 100 $$
- RO Salt Rejection : The percentage of salt (TDS) removed from the feed water. It’s calculated as:
$$ \text{Salt Rejection (%)} = \left(1 – \frac{C_\text{permeate salt}}{C_\text{feed salt}}\right) \times 100 $$
Where Cpermeate & and Cfeed are the concentrations of a salt (TDS) in the permeate and feed water, respectively.