SU861337A1 - Method of waste water purification from mercury - Google Patents

Description

 I

The invention relates to the purification of stop water (CB) from heavy metals, in particular from mercury.

The method can be used in the purification of industrial wastewater from mercury of all production of chemical, metallurgical, mining and processing and other industrial areas.

Lime processes for cleaning CB from mercury by separating mercury in the form of sparingly soluble compounds. Most often, mercury sulfide 1 and.

Sulfides and hydrosulfide alkali and alkaline earth metals, as well as hydrogen sulfide are used as sulfide reagent. Achieved a degree of purification of CB from mercury is 0.5-0.005 mg / l.

The closest to the invention to the technical essence and the achieved result is a method for purifying wastewater from mercury by precipitating it in the form of mercury sulfide and filtering it through sand or activated carbon Z.

The content of mercury in wastewater is 0.5-0.05 mg / l. For a deeper cleaning, the waste water is passed through an ion exchange resin. The mercury content in wastewater is reduced to 0.005 mg / l.

The process described is technologically cumbersome,

to require the use of, expensive, special, as well as tokicichi9, sulfide.

The aim of the invention is to increase the degree of purification .;

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This goal is achieved by passing alkaline mercury-containing wastewater through a column filled with polymer sulfur, followed by separation of mercury sulfide by filtration at pH 277.

Claims (3)

Wastewater treatment is thus based on a more active interaction of mercury and metal ions; mercury with sulfur, which is polymeric, i.e. thermodynamically more favorable state. The method is carried out as follows. . Wastewater treatment is carried out in an alkaline medium at room temperature. The resulting mercury sulphide is separated from the wastewater by filtration according to any known method at pH 2-7. Example 1. Sewage water containing 34.34 mg / l rtzgti (pH 10) is passed through a column filled with polymer sulfur at room temperature. 10 g of polymeric sulfur are required per 1 m of waste water. Run the waste water through the column to neutralize to pH 7 and filter off the precipitated mercury sulfide precipitate. Filtration is carried out through a layer of activated carbon. The content of mercury in the wastewater after filtration, determined by the atomic fluorescence method, is less than the SQS mg / l. The sensitivity of the instrument. Example 2. Sewage water containing 34.34 mg / l mercury (pH 10) is passed through a polymer-sulfur column at room temperature. The wastewater is then neutralized to pH 5 and filtered through a bed of diatomaceous earth or filter paper to separate mercury from sulfide. The mercury content in the wastewater after filtration is below 5. Example 3. Sewage water containing 34.34 mg / l mercury (pH 10) is passed through a polymer gray column at room temperature. One hundred hjno water after cleaning is neutralized to pH 2, filtered through a layer of activated carbon. The mouth content of 74 tons in the treated wastewater is lower. The technical and economic advantage of this method of purifying wastewater from mercury is that it is much simpler in technological design than the known sulfide method, since it does not require additional equipment prepared by sulphide solution ™, dosage, mixing. It is also significantly cheaper than the sulphide method and can significantly increase the degree of wastewater treatment and provide a residual mercury content in water below sanitary standards. Claim 1. The method of purification of wastewater from mercury, including treatment with sulfur-containing reagent followed by separation of mercury sulfide sediment by filtration, characterized in that, in order to increase the degree of purification, polymeric sulfur is used as sulfur-containing reagent, and the treatment is conducted in an alkaline medium. 2. A method according to claim 1, characterized in that the separation of mercury sulphide is carried out by filtration at a pH of 2-7. Sources of information taken into account in the examination of g :. 1. Japanese Patent No. 49-118111; cl. 91 C 91 / C 02 C 5/02, 1974. 2.Nilovaiov L.V. Wastewater treatment of non-ferrous metallurgy enterprises. M., Metallurgists, 1971, p. 127-128. 3.Kanzoz H.W. Chem. Ingr. Techn. 1975, 47, 9, 14, 8 602-603.