The problem of water flocculation
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After the drinking water is filtered through sand and carbon filters, and its calcium and magnesium ions are removed through resin exchange to soften it, 1. Will the water form flocs (clumps)? 2. Is the pH value of the solution weakly acidic at this time? Please ask the teachers for their guidance
Flocculation should not occur; flocculation happens only when there are many impurities present. If all impurities are completely removed, water should theoretically be neutral; unless the chlorine in it is not fully removed, it will become acidic, but alkalinity is unlikely
The resin exchange mentioned here removes calcium and magnesium ions; it clearly refers to cation exchange resins. After the cations are removed, bicarbonate and chloride ions remain in the water, giving the water an acidic character! In such an open environment, when water comes into contact with calcium, magnesium, and iron ions, precipitation occurs, which is what is known as flocculation; this does not happen in a closed environment ； Current water treatment generally involves cation-anion exchange. If the water turns acidic after this process, it indicates that the anion exchange resin has failed or is partially failed.