METHOD FOR REDUCING EMISSION INTO AQUATIC MEDIUM OF CHEMICAL ELEMENTS FROM GALVANIC SLUDGE Russian patent published in 2021 - IPC C22B7/00 C02F1/02 C02F1/36 C02F1/66 C02F9/02 C02F9/04 C02F9/10 C02F101/10 C02F103/16 

FIELD: waste processing.

SUBSTANCE: invention relates to a technology for neutralizing galvanic sludge from machine-building production by physical and chemical methods and can be used for the disposal of galvanic waste at enterprises of the machine-building industry and at enterprises connected with waste processing. The method of reducing the emission of chemical elements from galvanic sludge into the aqueous medium is that a solution of ferrous iron sulfate FeSO₄ is added to the suspension of galvanic sludge (GS), after which the resulting mixture is heated to a temperature of 70-80 °С and then a spent caustic solution (SCS) of chemical degreasing baths with a pH 10-11 is added to the heated mixture. This process is accompanied by ultrasonic vibrations with power of 150 W/cm2 and frequency of 35 kHz for 10 minutes at a mass ratio of the GS suspension, the FeSO₄ solution and the SCS equal to 3:1:0.6. The resulting precipitate is separated from the solution by filtration and dried at a temperature of 105 °C for 2 hours.

EFFECT: the use of a solution of ferrous sulfate, spent caustic solutions resulting from chemical degreasing of parts that are production waste as reagents for processing a suspension of galvanic sludge and ultrasonic vibrations intensify the oxidation processes of compounds formed as a result of mixing the above components into sparingly soluble ferrites for the possibility of their further safe placement at industrial waste landfills.

1 cl, 2 dwg