SU715501A1 - Method of waste water purification from zinc ions - Google Patents

Description

, (54) METHOD FOR CLEANING WASTE WATER FROM ZINC IOES

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for biological treatment, which requires additional consumption of reagents. Purpose of the invention is an increase in the degree of neTt and purification of zinc ions from the pack;

B; el d6 is reaped by the fact that the zinc containing sewage is treated with a solution of sodium carbonate before and phosphoric acid at a molar ratio of n, PO / Zn of 0.5-1.4.

  The selected pri interval provides the greatest degree of cleaning from

 zinc at the minimum cost of phosphoric chi-slots. The residual concentration of zinc ions in the effluent is 10.028-0.025 mg / l, and the purification rate reaches .99.96-99.98%

Example Take 1 l of waste water containing 177 mg / l or 71.5 mg / l Zn, 1220 mg / l HjSO, 3700 mg / l and having. Pour into the specified volume of effluent .10 1. ml of a 10% aqueous solution of carbonate ITSiipftjf to reach pri 7.5 and 0.11 ml of extraction phosphoric acid with a density of 1.325 g / cm (concentration HzRO 48.9%), which corresponds to molar the ratio of H PO / Zn equal to 0.5. Stir sewage water for 5 minutes. , Division of yards. The residual zinc content in water is determined by the standard method for zinc, Residual, concentration of zinc O, 028 mg / l, blending degree 99.96%. . .

Example 2, Same as in Example 1, but 9.8 ml of 10% sodium carbonate and dl solution are poured into the wastewater. Achieve a pH of 7.0 and 0.15 ml of phosphoric acid extraction, which corresponds to the -length ratio of HjPO / Zn2 equal to 0.7,. Residual concentration of zinc in sto715501

as 0,027 mg / l. The degree of purification is 99.97%.

 Example. As in Example 1, the new effluent is infused with 13.5 ml of 10% sodium carbonate solution to achieve, 0 and 0.33 ml of extraction phosphoric acid for. half a molar ratio of E PQ / Zn B to 1.4 effluent. The residual concentration of zinc is 0.025 mg / l, the degree of purification is 99.98%.

The method is simple and does not require the construction of a special compartment for the preparation of reagents, provides a high degree of purification of wastewater from zinc ions, and allows to obtain purified effluent from pH 7, which eliminates their additional treatment when applying for biological treatment.

Claims (4)

1. The patent of Japan 49-11810, cl. C 02 C 5 / 0.2, 1974. 2. USSR author's certificate number 353909, cl. C 02 C 5/02, 1973. 3. USSR author's certificate number 332054, cl. C 02 C 5/02, 1972. 4. USSR author's certificate number 568004, cl. C 02 C 5/02, 1977 (prototype). .