SU929590A1 - Method of purifying effluents from mercury - Google Patents

Description

(54) METHOD FOR CLEANING WASTE WATER FROM MERCURY

I

This invention relates to wastewater treatment and can be used to treat industrial wastewater. chemical and metallurgical production.

A known method of purifying solutions from mercury by reacting with sulfide-containing compounds and subsequent adsorption on activated carbon 1.

The disadvantages of the method are not sufficiently complete purification of solutions from mercury to 0.032-OD9O mg / l.

Most of the invention, by its technical essence and the achieved result, is a method of purifying wastewater from mercury by filtering it through activated carbon and oxychloride in the form of hardly soluble sulphide 2.

The disadvantage of this method is that the SR requires complex equipment and, moreover, provides a degree of purification of up to 92.5%.

The purpose of the invention is to increase the degree of cleaning,

This goal is achieved by the fact that in a joint venture of a special treatment of wastewater from mercury by filtration through activated carbon, the activated carbon is pretreated with sodium thiosulfate solution and npwxecc is carried out in an acidic medium.

At the same time, 2O-25% rastor aatri thiosulfate is used.

In addition, the process is preferably carried out at a pH of 1-7.

Aqueous solutions of sodium thiosulfate have a neutral reaction. Under sulfurization, sulfur is released, which R reacts with non-metallic mercury to form mercury sulphide (with {} quel food or neutral). In the alkaline alkaline sulfur medium, mercury will pass into a hygroscopic discharge and it will be impossible to isolate it from the solution, because the pH is kept no more than 1,

In the PRM | 4 < 2 > condition, the method is carried out as follows.

Mercury-containing wastewater, nme. They are passed through a column filled with active charcoal treated with 200–25% sodium thiosulfate solution. The pdfdain consistencies are carried out both continuously and periodically.

Example. The mercury-containing solution from the mercury electrolysis shop {co: mercury holding 4.73–24.8 mg / l, pH 1–7) passes with a flow rate of 15 mp / min to a column of activated carbon treated with a 2O solution of sodium sulfate. Activated carbon is taken at the rate of 50-1OO mg of coal per 1 mg of mercury. Contact time is 10-15 minutes.

For the treatment of activated carbon with thiosulfate per 5O g of carbon, 10O ml of 20% thiosulfate solution is taken.

sodium and incubated for 24 hours. I,

The mercury content in the purified solution is determined by using a photocolorimeter with dithizone. Mercury in the purified solution is absent. The method provides 1OO% wastewater treatment from the mouth tH. The production is carried out both continuously and intermittently.

Claims (3)

1. A method of purifying wastewater from mercury by filtration through activated carbon, characterized in that, in order to increase the degree of purification, activated carbon is pretreated with sodium thiosulfate solution and the process is carried out in an acidic medium. 2. The method according to claim 1, about tl R h and y i and the fact that they use a 2O-25% solution of sodium thiosulfate. 3. Method according to paragraphs. 1 and 2, that is, that the process is carried out at a pH of 1-7. Sources of information taken into account in the examination 1.Patent Franz No. 2179926, cl. C O2 C 5/02, 1973. 2. Ya. M. Poisonous metals. M., Medicine, 1972, p. 113-114.