Experimental Research On Micro-Quantity Heave Metal Ions Removal From Drinking Water By Weakly Basic Anion Exchange Resins And Its Regeneration

By means of static and dynamic experiments, lots of research on the effect of micro-quantity heavy metal ions (HMI) removal by weakly basic anion exchange resins (WBAER) from drinking water (DK) with alkali metals, alkaline-earth metals and anions at high concentration, has been done. By varying flow velocity and the concentration of HMI (Hg2+) in influent water and adding usual cations (Ca2+, Mg2+) or anions (Cl-, SO42-) into raw water, the effects of HMI removal by WBAER and cations exchange resins from DK have been contrasted. The results show that when the concentration of HMI (Hg2+) in influent water is every low, the effect of HMI removal by WBAER from DK is much better than cations exchange resins. With cations (Ca2+, Mg2+) at high concentration in raw water, WBAER has better selectivity to HMI in water, however the selectivity of cations exchange resins is worse. The anions in raw water such as Cl- which is able to react with HMI can make cations exchange resins lose the capability of HMI removal, but it has no effect on WBAER (D301G). In a word, WBAER can effectively remove micro-quantity HMI from DK with alkali metals, alkaline-earth metals and anions at high concentration.On the basis of lots of regeneration experiments of WBAER (D301G), the best regeneration manner (regurgitation regeneration), the optimal regeneration agents (H2SO4 and NaOH) and the optimum operating parameters of regeneration are obtained.In addition, a series of analyses about theoretical principles of HMI removal by WBAER from DK with alkali metals, alkaline-earth metals and anions at high concentration and regeneration of WBAER, have been analyzed. And factors, such as flow velocity, the concentration of HMI in influent water and usual cations (Ca2+, Mg2+) or anions (Cl-, SO42-) in raw water, which can influence the effect of HMI removal by WBAER from DK has also been discussed.