Defluorination process for drinking water

Abstract

The invention discloses a defluorination process for drinking water, belonging to the technical field of water treatment. The process comprises the following steps of: (1) pouring 50-150 ppm of poly-aluminium chloride in raw water; (2) pouring 10-50 ppm of kieselguhr or kaolin or attapulgite in the water, and adequately mixing; (3) filtering by using a granular hydroxyapatite filter material; and (4) filtering by adopting sand filter or a fibre ball filter, so as to obtain the drinking water. With the adoption of the defluorination process for the drinking water disclosed by the invention, an ideal defluorination effect can be stably obtained for a long time, the hydroxyapatite defluorination filter material does not need to be regenerated during a running process, a complex process for updating the whole filter material is avoided, the poly-aluminium chloride after defluorination, the fallen hydroxyapatite defluorination filter material dust, the poured kieselguhr and the like are separated from the water via flocculation reaction, so that the problem of the standard exceeding of aluminium ions in the water after the treatment is avoided.

Description

technical field [0001] The invention relates to a water treatment process, in particular to a drinking water defluorination process. Background technique [0002] Fluorosis caused by drinking high-fluoride water is an endemic disease worldwide. In mild cases, it can cause dental fluorosis, and in severe cases, it can cause skeletal fluorosis, resulting in osteoporosis, bone deformation, and even paralysis and loss of working ability. China is one of the countries with the most severe fluorosis in the world. Except for Shanghai, it spreads all over the country, mainly in rural and pastoral areas with relatively backward economy. At present, the population of sick villages due to high fluoride water poisoning is as high as 80 million. Drinking water Fluorine removal is particularly important. [0003] At present, the common defluoridation technology at home and abroad mainly adopts adsorption method and coagulation precipitation method, but these two methods have certain limi...

AI Technical Summary

Problems solved by technology

The regeneration of the adsorbent in the adsorption method is one of the key factors affecting whether the adsorption material can be used as a fluoride removal filter material. Since the service life of the fluoride removal filter material is short, when the fluoride removal filter material cannot be regenerated, it needs to be replaced as a whole The replacement process of the filter material is very troublesome, which is an important reason why many defluoridation equipment cannot be used for a long time

Excessive aluminum ions in the coagulation-sedimentation method is a very serious problem, and the coagulation-sedimentation method alone often cannot make the fluorine in the effluent reach the standard

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