Reverse Osmosis System Very Effective

Reverse osmosis (RO) is a very effective membrane separation unit operation, Reverse Osmosis System is relying on reverse osmosis membrane under pressure in the solution of solvent and solute separation process. Reverse osmosis technology can reduce the load of ion exchange resin by more than 90%. The amount of regenerant used in resin can also be reduced by 90%. In addition to salt removal, Reverse Osmosis System it can remove particulates, Reverse Osmosis System organic substances and colloidal substances in the water and reduce the pollution of ion exchange resin , To extend the service life has a good effect.

However, for a long time, reverse osmosis technology seems to be powerless for the removal of free CO2 contained in water because traditional reverse osmosis techniques must control the LSI (ie, Langley's saturation index) in the influent to prevent reverse osmosis membrane fouling The The LSI value of an important parameter is the PH value of the influent, if the PH value is acidic, it is not easy to scale, Reverse Osmosis System if the pH is alkaline, the fouling tendency is very obvious. Therefore, the traditional process in the reverse osmosis system before adding HCl solution, Reverse Osmosis System can well prevent CaCO3, MgCO3 and other precipitates fouling; and rarely in the reverse osmosis system before adding NaOH solution.

At present, the most widely used is the carbon dioxide degassing column. Since the water contains a large amount of bicarbonate alkalinity, after the H-type ion exchanger (ie, cation exchange bed), Reverse Osmosis System the H + on the resin is replaced with water and becomes carbonic acid , Reverse Osmosis System So the CO2 bed is generally placed behind the cation exchange bed, in front of the anion exchange bed. When the PH value of water is less than 4.3, the carbonic acid in water is almost completely in the form of carbon dioxide, as follows:

H + + HCO3- = H2CO3 = CO2 + H2O

When H + increases, that is, the lower the pH, Reverse Osmosis System the reaction is carried out to the right, at this time, with a device water sprayed from the next, the air from the next blast, so that the air flow and water droplets full contact, Of the carbon dioxide is very small, Reverse Osmosis System the partial pressure is very low, only 0.03% of atmospheric pressure, according to Henry's law, through the H-type ion exchanger treatment of water, due to high carbon dioxide partial pressure, into the low partial pressure air flow And thus remove the water in the carbon dioxide, that is, to remove a large number of anions in the water anion HCO3-, which can greatly reduce the burden of the bed, Reverse Osmosis System improve the cycle of the amount of water, reduce the consumption of renewable agents.

Vacuum degassing tower is also a way to remove CO2, in addition to the removal of O2 and other substances in the water, removal efficiency than the removal of high CO2 tower. Reverse Osmosis System It works by using a device to spray the water from the next, after the filter material dispersed, the water CO2 and O2 escape, while the vacuum pump in the middle of the tower vacuum, CO2 and O2 by the vacuum pump suction, Reverse Osmosis System degassing After the pure water flow to the bottom of the tower, the mixed bed after the pump pressure into the post-treatment mixed bed. If the vacuum degassing column is weakly acidic, the carbonate in the water can also be removed in large quantities because when the pH of the water is less than 4.3, the carbonic acid in the water is almost entirely in the form of carbon dioxide due to the non-degassing reverse osmosis Water is generally weak acid, so the vacuum degassing tower is generally placed in the post-reverse osmosis.

Vacuum degassing tower structure is more complex, Reverse Osmosis System large units have degassing tower, vacuum pump, etc., in order to ensure uniform dispersion of the water, the filter layer height must be set very high, resulting in degassing tower height of ten meters, the equipment occupies a huge space, In addition, because the degassing tower level control is very strict, the liquid level is too high, Reverse Osmosis System easy to degassing efficiency, too low, Reverse Osmosis System easily lead to pump suction, causing production accidents, Reverse Osmosis System so the use of the level gauge must be very sensitive. Although the vacuum degassing tower will not bring new impurities into the outside world, but because of the complex structure of the device, large footprint, high operating costs, Reverse Osmosis System so the actual production and application subject to certain restrictions.