SU432763A1 - Wastewater treatment method - Google Patents

Description

one

The invention relates to the field of purification of wastewater production of freon.

The known purification method consists in treating the waste water with a 10% - (alkaline agent solution and precipitating antimony derivatives.

However, the degree of wastewater treatment by a known method is only 87%.

The foregoing method differs from the known one in that the treatment of alkaline agents is carried out to a pH of 7.5-8.5 in the presence of an alkaline or alkaline earth metal halogened followed by Vbeden.M to the processed iron salt to pH 6.5-7.5. .

The proposed method allows to increase the degree of purification to 100% and to obtain an easily filtered precipitate.

Example. In the reactor, equipped with a reflux condenser, a broom, a thermometer, a funnel and electrodes (ECL 43-07, autoTepMOKOMneHcafiQpOM TKA-1 and auxiliary in the electrolyte EVL-1M) from a pH meter “pH 262, load 105 g of a 20% aqueous solution of technical carbonate sodium or equivalent amount of a 20% sodium hydroxide solution. 15 g (4.5 g in terms of antimony) of the spent freon production catalyst 11.12 are introduced into the portions heated up to 95-100 ° C in portions through a funnel for 10-15 minutes.

When moving, and K (the pH of the reaction mass is maintained at 7.5–8.5 by introducing an additional amount of a coarse catalyst or alkaline agent until the evolution of organic fluorine and chlorine vapors (tetrachloro, carbon ida, freon, etc.) and carbon dioxide is completed. Then, an aqueous solution of calcium chloride (1.4 g in terms of) is added to the reaction mass and the pH is lowered to 6.5-7.5 by the introduction of a freshly prepared aqueous solution of ferric chloride or iron sulfate (0.5 g in terms of Fe +). The pH needed to be adjusted to the indicated value by the addition of an alkaline agent.

After stirring, cooling and holding for 30 minutes, the reaction mixture was filtered.

The precipitate is washed with 100 ml of water. The weight of the precipitate in terms of dry 9.5 g. The precipitate contains (wt.%): Sb (total content) 34.0- 46.9; Fe + 3 5.25; C1 (total content) traces, Ca + 2 14.6; F- 1.5-9.0.

The ECL 43-07 electrode was replaced with ECL 63-07 and in the same reactor the filtrate and washings were combined, and solutions of chlorine or sulfuric acid were added to this solution (150 g) having a pH of 6.5-7.5.

iron (0.2 g in terms of Fe +) and calcium chloride (0.4 g in terms of Ca + 2). If necessary, the addition of an alkaline agent adjusts the pH of the medium to a value of 6.5-7.5.

The reaction mass is kept at this pH with stirring for 1 hour and filtered. The sediment weight in terms of dry 2.1 g.

Composition (wt.%): Fe + s to 9.5; Ca + 2 dr 18.9; F 0.5-3.5; Sb (total content) 0.4-2.1; C1 (total content) to 10.0.

The weight of the filtrate is 160 g. Content in the filtrate, mg1l: C1- 44.1-74.0; p-1.0-6.4. Organic and other impurities 3.5-20.

Claims (1)

Invention Formula The method of purifying wastewaters by producing flukes by treating them with an alkaline agent, characterized in that, in order to increase the degree of purification and obtain easily filtered sludge, the treatment with an alkaline agent is carried out to a pH of 7.5-8.5 IB in the presence of an alkali or alkaline earth metal halide the subsequent introduction of ferric salts to the treated area to a pH of 6.5-7.5.