SU1745686A1 - Method of neutralization of borofluorate containing industrial sewage - Google Patents

Abstract

SUMMARY OF THE INVENTION: Lime milk is injected into drains until a pH of 8-10 is reached, mixing is carried out with heating up to 82 ° C, followed by precipitation when a high-voltage electric field is applied using electrodes, the surface of which is covered with insulating material and a low-voltage field using aluminum electrodes. 1 tab.

Description

This invention relates to a wastewater treatment technique. mainly for wastewater treatment. containing bortorate compounds, and can be used in the chemical industry and other areas of national economy, as well as to clear the water from other compounds that require thermal decomposition.

Two methods are used for the purification of the industrial bortyrate effluent: ion exchange and reagent.

The known methods have the following disadvantages: ion exchange resins do not provide reliable purification from complex bortorate compounds and require pretreatment of runoff, and the use or storage of eluates is not resolved. The reagent method requires prolonged exposure of the volume being cleaned under mechanical agitation and, as a result, both methods require the occupation of large areas.

There is a method according to which from 1 the worked solutions are fed into the reactor with a mixing device. A 30% solution of calcium oxide to pH 4.0–4.5, then a 20% solution of soda ash to pH 7.0– 7.5 and again calcium oxide to pH 8.5–9.0 are fed into the reactor. . Stand

the reaction mixture is stirred for 2 hours. The precipitate of lead and tin oxides is filtered off on a capacitive filter, washed with water and dried at 100 ° C for 1 hour. The filtrate and washings from the filter are sent to the acid-alkaline waters of the plant.

This method makes it possible to extract only heavy metal ions from the runoff, and tin hydroxide is poorly filtered, and the acid-alkaline waters sent to complex bortorate compounds prevent its purification.

The known methods do not allow the purification of water from the fermentative compounds, since the reagents available for sewage treatment do not produce insoluble compounds in water.

The stalk of the invention is to increase the efficiency of industrial effluent treatment, facilitate operation and save space.

The goal is achieved by those. In a fermentative drain, preheated, lime milk (calcium oxide solution) is dosed as a reagent until the pH is adjusted to 8.0-10.0 and the flow is heated to 82 ° C, the solution and the drain are thoroughly mixed. As a result, bortorate

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The compounds completely decompose to form hydroxides and bicarbonates of metals (lead, copper, tin, etc.) contained in the effluent, boron calcium salts and calcium fluoride. To remove the residual concentration of dissolved calcium fluoride, aluminum electrodes with a voltage of 9–12 V must be used (the corresponding aluminum salts can be dosed for this purpose). Suspended particles are removed from the flow due to the fields created by high-voltage electrodes with an insulating layer at a voltage applied to them from 25 to 30 volts V. High-voltage electrodes are perpendicular to one another (if there are four of them, or under acute angle if more than four) and along the direction of flow of the stream to be purified. Low voltage electrodes are located along the flow of the purified drain between high voltage electrodes and closer to the central part of the stream.

Purification of the spent bortorate solution is carried out according to the proposed and well-known method, moreover, with an exposure time of about 20 hours. Results data are tabulated.

The value is not determined to mean that this component is in solution in lower concentrations than the sensitivity of the available chemical analyzes, i.e. less than 0.05 mg / l.

The use of the proposed method for purification of industrial borther effluent provides, in comparison with the known, the following advantages: the complete absence of highly toxic compounds in

the purified stream due to decomposition of the fermentative compounds; deep purification from toxic heavy metals (lead, copper, etc.) due to the absence of a complexing boron fluoride ion; simultaneous purification from fluoride ion to a concentration below the maximum permissible; allows you to clear the drain on the stream, since at the indicated pH and temperature parameters and the application of high-voltage and low-voltage fields, conditions are created for the decomposition of bortorate compounds and the purification of fluorine in fractions of seconds; the process can be automated, while occupying considerably less space than the used ones; It reduces the ingress of pollutants into the environment and, as a result, improves the environment.

Claims (1)

DETAILED DESCRIPTION OF THE INVENTION Claims: A method for purification of a fermentative industrial effluent, including the introduction of a reagent, mixing and separation of the precipitate, characterized in that. in order to increase the degree of purification when the content of a wide range of metals in the effluent boron compounds is used, lime milk is used as a reagent, which is injected until a pH of 8-10 is reached, stirring is carried out while heating to 82 ° C, and deposition a high voltage electric field using electrodes, the surface of which is covered with an insulating material, and a low voltage field using aluminum electrodes.