RU1721989C - Method of removing ions of metals from waste - Google Patents

Abstract

The invention relates to methods for water purification, can be used to purify industrial and other wastewater from metal ion impurities and allows to reduce the duration of the process and increase the degree of purification. To carry out the method, water containing metal ions is treated with a suspension of iron powder. The suspension is prepared by electroerosive dispersion of iron in water and kept until the formation of magnetite 1 table. .

Description

The invention relates to methods for treating water and can be used to treat wastewater, wastewater and other waters from impurities of metal ions.

The aim of the invention is to reduce the duration of the process and increase the degree of purification.

Example. Take 10 kg of chip from low-carbon steel 20 and subjected to electroerosive dispersion. Dispersion is carried out by electric discharges between the pieces of chips in the flowing industrial water, which carries out the flow of electro-erosion products from this device. The specific energy consumption for dispersion is 4 kWh per 1 kg of steel. The suspension exiting the dispersion device is sent to a filter press, where the powder is separated from the water, which is returned to the dispersion device for reuse. A wet cake from a filter press having a mass ratio T: W 1: 1 is collected in a suspension storage vessel, where it is kept under periodic stirring (once a day) for the time indicated in the table, but not less than 3 hours. To speed up the aging process, the suspension is boiled. The suspension is then bottled and sent to the consumer. In the consumer, the suspension is used to purify galvanic wash water containing metal ions, the concentration of which is shown in the table. For cleaning, 100 L of wash water is taken into a conical bottom vessel having a drain valve in the lower part. The suspension is added to the vessel in the amount indicated in the table in terms of dry matter. The contents of the vessel are stirred for 1 minute, then the water is allowed to stand in the same vessel for 0.5 hours. In this case, the suspension in the coagulum vessel

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it precipitates and precipitates, and the water clarifies. Thereafter, a tap in the lower part of the vessel is opened and the sediment is drained together with part of the water into the sediment collection vessel. When the suspension (sediment) stops flowing from the tap and the clear (clarified) water starts to flow, the discharge is carried out into the collection vessel of the clarified water. Then the clarified water is filtered through filter paper on a filling funnel and collected in a collection vessel of water. The precipitate from the collection vessel is filtered on a vacuum filter. The filtrate water obtained from the vacuum filter is then filtered through filter paper on a filling funnel and also drained into a collection vessel of water. Water from the collection vessel is analyzed for the content of residues of heavy metal compounds by the photocolorimetric method. The results of the analyzes are shown in the table, which summarizes the results of the experiments and provides comparative data of the known method.

From the data of the table it follows that the proposed method allows to reduce the consumption of iron per unit of the mass of heavy metal impurities extracted from the purified water from 58-300 to 7.7-26 g / g; reduce environmental pollution by sludge by reducing the mass and volume of sludge generated during the purification of a unit volume of water from 15-75 to 20-50 g / m; to increase the productivity of the water purification process by increasing the speed of the purification process and reducing the required mixing time from 30-60 to 3-5 minutes, expand the range of metals that are extracted from the water to be purified, in particular, chromium, tin, and aluminum are extracted.

(56) Japanese application No. 52-45665, cl. 13/7 / A2, C 02 C 5/02, 1977.

Table continuation

Claims (1)

SUMMARY OF THE INVENTION 1. METHOD FOR CLEANING WASTE WATER FROM METAL IONS, including treating with powdered iron with stirring and separating the precipitate, characterized in that, in order to reduce the duration of the process and increase the degree of purification, the treatment is carried out by water suspension obtained by electrosrising dispersion of iron in water and aged until magnetite is formed. 2, The method according to claim 1, characterized in that the aqueous suspension is maintained for at least 3 hours. 3, The method according to claim 1, characterized in that the suspension is boiled during aging.