How to reduce the operating cost of RO reverse osmosis water treatment equipment?

Author: Hongjie Water

The principle of reverse osmosis technology is to separate other substances from water based on the fact that they cannot penetrate the semi permeable membrane under the action of osmotic pressure higher than the solution. The pore size of reverse osmosis membranes is very small, so they can effectively remove dissolved salts, colloids, microorganisms, organic substances, etc. from water. The RO system has a high operating cost due to its high-pressure pump and the need to add specialized scale inhibitors. So how can we reduce the operating cost of the RO system?

1. Select ultra-low pressure reverse osmosis membrane

The operating pressure of conventional reverse osmosis membranes is between 1.3 and 1.5 MPa, while the operating pressure of ultra-low pressure reverse osmosis membranes is around 0.8 MPa or even lower (closely related to water temperature), which can save more than 30% of power consumption. For large RO systems, it can basically offset over 70% of the annual depreciation cost of the membrane, resulting in more significant savings.

2. High pressure pump equipped with frequency converter

The high-pressure pump equipped with a frequency converter can not only alleviate the water hammer impact when the water pump starts, but also reduce the throttle energy consumption of the valve by setting a reasonable operating pressure. It can save at least 15% of energy on a quarterly basis throughout the year.

3. Reasonably calculate the dosage of scale inhibitor

By analyzing water quality data and optimizing the dosage of chemicals, it is usually possible to save 20% or even more in the cost of chemicals.

4. Increase the number of membranes appropriately to reduce operating pressure

By appropriately increasing the membrane area, the operating pressure of the membrane can be reduced to a certain extent, thereby reducing power consumption.

5. Environment

If the water temperature is higher than 45 ℃, it will shorten the service life of the membrane. Generally, the water temperature should be controlled below 40 ℃, and cooling measures should be taken if necessary. For RO systems, wastewater containing strong oxidizing or easily precipitated substances can shorten the membrane service life. When designing a system, from the perspective of its safety, increasing the pre processing safety margin and installing a protective shutdown design can avoid causing such problems.

6. Use anti pollution reverse osmosis membranes

Anti fouling membrane is a reverse osmosis membrane element developed for water quality in China, which has high desalination rate, high water yield, high chemical durability, high pollution resistance, and ultra-low pressure operation. Under the same water quality conditions, energy consumption can be reduced by 30% -40%, and the membrane element is easier to clean. While effectively solving the increasingly severe water source pollution problem, it effectively reduces operating costs and brings higher value to customers.

Generally speaking, the service life of reverse osmosis membranes is about 2-3 years, which is a normal phenomenon. However, if improper operation occurs, it will shorten the service life of the membrane, thereby shortening the service life of the equipment