What are the pollution factors of ion exchange resins?

After using ion exchange resin for a period of time, impurities in the water will be contaminated, resulting in a deterioration of the effluent quality. If color darkening or other phenomena are found during the operation of ion exchange resin, it may be that the ion exchange resin has been contaminated. Pollution can be divided into many types, such as suspended solids pollution, organic matter pollution, and the contaminated resin can affect the water quality and cost of water removal.

What kind of pollution does ion exchange resin suffer from?

The common types of pollution in the use of ion exchange resins are as follows:

Pollution caused by organic matter, oil, suspended solids, colloidal substances, high valent metal ions, and impure regenerants.

What are the reasons for the pollution of ion exchange resins?

Pollution caused by organic matter

The main cause of organic pollution is the exchange reaction between linear macromolecules with negative functional groups such as fulvic acid, humic acid, and tannic acid produced by the decay of biological limbs and ion exchange resins. The main phenomenon of organic pollution is that the color of the ion exchange resin darkens, the amount of washing water gradually increases, the conductivity increases during operation, and the pH value decreases.

Pollution caused by oils and fats

The main reason for oil pollution is due to the presence of lubricating oil and other lipid substances in the raw water. At the same time, due to the inadequate infiltration of some oil into the water treatment system equipment, ion exchange resins are contaminated. The main phenomenon of oil pollution is that the color of ion exchange resin turns black, the exchange capacity decreases, and the resin is bonded together, resulting in uneven water flow in the resin layer and biased flow, leading to poor effluent quality.

Pollution caused by colloidal substances

Colloidal particles in water often carry negative ions, which contaminate the anion exchange resin. Among colloidal substances, colloidal silicon poses the greatest harm to the resin. It adsorbs and polymerizes on the surface of the bleached anion exchange resin, preventing the resin from conducting ion exchange.

Pollution caused by high valence metal ions

The reason for pollution caused by high priced metal ions is that the water source contains iron, the inlet pipeline or exchanger is corroded to produce iron compounds, and the regenerant contains iron impurities. There are generally two forms of pollution, one is in the form of colloidal or suspended iron compounds entering the exchanger, and the other is in the form of ferrous ions entering the exchanger. The main phenomenon of high priced metal ion pollution is that ion exchange resins appear noticeably darker in color, even appearing black.

Pollution caused by impure rejuvenators

The regeneration agent of ion exchange resin is often impure and mixed with many impurities, especially in caustic soda (NaOH) where there are many impurities such as Fe3+pure, NaCl, Na2CO3, etc. It is particularly emphasized that the regeneration solution contains Fe. When 0: and NaCl02 are present, high valent iron salts will be generated, which will cause the most serious pollution to the ion exchange resin.