SU1323537A1 - Method of removing sexivalent chromium from waste water - Google Patents

Abstract

This invention relates to wastewater treatment technology for hexavalent chromium and can be used in the production of chromium 1x products, chromium compounds and other industries where soy is used. Hexavalent chromium denines. The purpose of the invention is to improve the degree of purification at a variable initial chromium concentration and intensify the process, as well as to ensure the possibility of automating the process and reducing the consumption of barium hydroxide. The goal is achieved by the fact that the wastewater treatment process is carried out by treating them with barium hydroxide in the presence of calcium hydroxide additives, taking in an amount of 1.8-9.0 of the amount of hexavalent chromium in the initial solution. 1 hp f-ly. with b (L with

Description

1 13235372

The invention relates to the technology. After aging for 20 minutes, the cleaning of waste water containing neck-penzia is filtered through a cloth of the type

equivalent chromium, and can be belting. The filtrate contains 3 mg / l.

used in the production of chromium-Cr (VI), the degree of purification is

products, compounds of chromium and other - 596.2%. Excess barium hydroxide in industries where pressure 1.2 is used.

hexavalent chromium compounds. Example 4, In waste water,

The purpose of the invention is to increase stee containing 40 mg / l of Cg (VI);

fines for cleaning with variable initial hydroxylene cap to pH 11.5 (ratio of chromium and intensification of 0 Ca (OH) ..,

S / I - g - 3,0), and then the hydro-process, as well as the provision of possible Cr (, VI)

automation of the process of cleaning barium oxide to a pH of 12.3 (the ratio of

and reducing the consumption of barium hydroxide .Ba (OH): Cr (Vl) 5). After aging Example 1. In the waste water, the ki solution is separated from the precipitate. The resultant cleaning during washing of parts is 95%, and the excess galvanic chromium current. barium hydroxide 1.6. a formulation containing 80 mg / l Cg (VI). Example 5. In waste water,

and having a pH of 6.0, pre-containing 120 mg / l of Cg (VI) are introduced,

prepared a mixture of hydroxy-hydroxide drops to a pH of .11.5 (calcium and barium ratios (ga () l) wearing Q Vyj--) 9.0) and then an amount corresponding to barium oxide to pH 12.4 (ratio

Ba (OH) 2, g, / Ca (OH) j Ba (OH) 2. h

Claims (1)

wearing cTCvTT ™ cr (Vl), plant height 5.8), After stirring, the core is separated from the precipitate. The filtrate of the juice for 30 min. The solution decanted. Holds 6.2 mg / l Cr (VI), the degree is cleared and analyzed on the content of the stock is 95%, the excess of hydro- Cr (VI), the concentration of Cr (VI) -barium oxide is 0.9, thief is 3.2 mg / l, which corresponds to a purification degree of 96%, claims PRI me R. 2, similar to the example 1 1 in waste water; containing 80 mg / l 1, Method of cleaning waste water from Cr - (VI) and having a pH of 6, are added to the equivalent chromium by mixing them with a suspension of hydroxide test with barium hydroxide followed by calcium containing 100 g / l CaO to 35% of the resulting separation. „LSa (OH) g. „H sediment from solution, отлич 10 (ratio - /; - t, -7 - 1.8), Cr (Vl). And with the fact that, in order to increase then the degree of purification with variable at room temperature is saturated The solution is a barium hydroxide solution of a high chromium concentration and intensity. , s / va (oH) 2 o, .. Orification of the process, the latter lead pH 11.5 (ratio.-L, 3.6. /  . Cr (VI) in the presence of hydroxide additives Elk of the extract for 30 min. Rast-calcium, taken in the amount of 1.8 gus, is decanted and analyzed for co-9.0 of the amount of hexavalent Holding Cr (vi). Its chromium concentration. is 3.5 mg / l. The degree of purification is 2, the method according to claim 1, differs by 95.6%, and the excess is hydroxy and by the fact that, in order to provide a barium, 1.1, it is possible to automate example 3. In this process, and reducing hydroxide consumption Of the same composition, qadi-bari hydroxide is introduced, the wastewater is first treated to achieve a pH of 11.5 -50% with calcium hydroxide until it reaches (ratio Ca (OH) 2; Cg (VI) 5.8), pH 10 , 0-11.5., And then and then barium hydroxide to pH 12.4 with barium hydroxide to a pH value of 11.5 (the ratio of Ba (OH) 2: Cr (VI) is 3.9), 12.4, VNIShSh Order 2929/28 Circulation 851 Subscription Prod. pr-tie, Uzhgorod9 st. Project, 4