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What is the working principle of the softening filter?

Jun 09, 2018

Hard water softening to use ion exchange method, it is the purpose of using cation exchange resin with sodium ion exchange for calcium and magnesium ions in hard water, in order to reduce the concentration of calcium and magnesium ions in the water.

Its softening reaction is as follows:

Ca2 + + 2 na - EX - Ca - EX2 na + 1 + 2

Magnesium 2 + + 2 na - EX - Mg - EX2 na + 1 + 2

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The EX in the formula refers to the ion exchange resin, which combines the Ca2+ and Mg2+ to release the Na+ ions originally contained in it.

Resin matrix (resin matrix) in sodium chloride, in the process of water softening, sodium ions will gradually be used exhausted, the softening effect of exchange resin will reduce gradually, the need for reduction (regeneration), namely every fixed time to join a particular concentration brine, generally is 10%, the responses are as follows:

Ca-EX2+2Na+ (brine).

Mg-EX2+2Na+ (brine).

If no cationic softening of water treatment process, not only will have a reverse osmosis membrane calcium magnesium body deposition that reduce efficacy or even destroy the reverse osmosis membrane, also easy to get hard water syndrome patients.

The hard water softener also causes the problem of bacterial reproduction, so the equipment needs to have the function of the reverse charge, after a period of time, it will be reversed to prevent too many impurities to absorb it.

Another noteworthy problems of sodium is high blood disease, because dialysis water softening and timer to control the reduction process is * and normal reduction occurs mostly in the middle of the night, this is the valve in the control, in the event of failure, a lot of salt water will pour into water, causing the patient's disease high blood sodium.

The automatic sodium ion exchanger USES the principle of ion exchange to remove the calcium and magnesium in water.

When containing raw water hardness ions through the switch in the resin layer, the calcium and magnesium ions in the water with resin adsorption of sodium ions in the displacement and the resin absorption of calcium, magnesium ion and sodium ion in the water, so from escaping from the exchange of water is to remove the demineralized water hardness.