RU2006483C1 - Method for purification of sewage from organic impurities - Google Patents

Abstract

FIELD: methods for purification of sewage water from organic impurities. SUBSTANCE: sewage water is treated with a magnetic field in the bed of ferromagnetic particles. Sewage water is passed with a volumetric flow rate of 15-25 m cubic/h. Simultaneously a mixture of hydrogen with aluminium sulfate is introduced into the flow, the components relationship being of 15-10: 1. The mixture is added into the sewage water in the amount of 0,03-0,05 g/l. EFFECT: enhanced quality of purification. 3 tbl

Description

 The invention relates to methods for wastewater treatment from organic substances, in particular wastewater of the paint and varnish industry, which uses paint and varnish products, alcohols, and allows to increase the efficiency of wastewater treatment.

 Wastewater of paint and varnish production contains soluble organic compounds, such as phenol, formaldehyde, alcohols, esters, solvents, the presence of which in the effluent worsens the self-cleaning process, violates the oxygen regime. These wastewaters are highly concentrated and, by the nature of chemical compounds, difficult to be cleaned by known physicochemical methods.

 Purification from organic impurities is achieved using a number of physicochemical methods, such as sorption, extraction, oxidation.

 A known method of wastewater treatment of a paint and varnish factory with a COD of 3400 mg O / L, which is heated to 60 degrees, add sulfuric acid to pH 2.3 and sodium dichromate, then barium hydroxide is introduced to pH 7, and the precipitate is separated. The clarified water is passed through an activated carbon column. The COD purification efficiency was not more than 75% [1].

 In addition, the implementation of this method requires additional reagents, which in turn re-pollute the effluents. The effluent treatment efficiency is unstable.

 The decomposition of hydrogen peroxide occurs with the formation of oxygen. Molecular oxygen has a binding energy of 117 kcal / mol, but despite its high oxidation potential, it is a passive oxidizing agent. In order to prevent the formation of molecular oxygen, it is preferable to use an ozone stabilized solution of hydrogen peroxide [2].

 A known method of treating water in the presence of a ferromagnet. This method can be implemented when treating wastewater containing impurities in the form of ferromagnetic particles. For example, wastewater from metallurgical production. The method does not allow to purify waste water from organic impurities.

 Each of these known methods separately does not allow for effective treatment and to operate in a stable mode in the event of overloads and a changing composition of wastewater.

 Such an effect on wastewater, such as ultraviolet rays, magnetic field, high-frequency currents, allows mainly to disinfect water from pathogenic microorganisms [3].

 Closest to the claimed technical solution for the intended purpose and technical essence is a method of treating wastewater containing soluble organic substances, including magnetic field treatment in a layer of ferromagnetic particles and in the presence of hydrogen peroxide in an amount of 0.005-0.015% [4].

 The disadvantages of this method are the low degree of purification from organic impurities, the inability to effectively purify highly concentrated juicy water. This method can be effectively used mainly for sterilization.

 To achieve a high degree of purification for all organic and mechanical impurities present, the possibility of implementing the method in a single compact structure using the non-sedimentation technology, a method is proposed for treating wastewater of paint and varnish production.

 The method is as follows.

Wastewater is passed through a magnetic field with a volume velocity of 15-25 m ³ / h while simultaneously introducing a mixture of hydrogen peroxide and aluminum sulfate in an amount of 0.03-0.05 g / l, with hydrogen peroxide and aluminum sulfate taken in the ratio of 15 -20: 1.

The treatment of waste water with a mixture of aluminum sulfate and hydrogen peroxide in a magnetic field and in the presence of ferromagnetic particles allows not only to intensify the cleaning process, but also to reduce the concentration of organic impurities to 0.05 mg / l and COD to 70-80 mg O ₂ / l, despite the fact that these impurities are not ferromagnetic impurities that could be deposited on ferromagnetic working fluids.

 Under the influence of a magnetic field, a mixture of hydrogen peroxide and aluminum sulfate contributes to a significant reduction in surface tension and a change in lyophobicity at the phase boundary. The degree of cleaning is affected by a number of emerging factors, acoustic vibrations, magnetic field, local high pressures.

 As a result of this, organic impurities are almost completely precipitated.

 The water treated in this way is most easily amenable to biological treatment, which is recommended for the final treatment of wastewater from paint and varnish production.

 PRI me R. Use wastewater of the three compositions shown in table. 1.

 First, the wastewater enters the pressure flotator, in which the primary purification from mechanical impurities is carried out, after which it is neutralized with a 10% solution of milk of lime to a neutral pH.

 Then, the wastewater is passed through a ABC type V-150K-07 vortex electromagnetic apparatus, the working chamber of which is filled with ferromagnetic particles in the form of ball-bearing steel needles. The device is produced by a magnetic field of 800-1000 E.

 At the same time, a mixture of a 40% hydrogen peroxide solution and a 5% aluminum sulfate solution is fed into the apparatus.

 The volumetric rate of the wastewater supplied and the amount of the mixture are controlled by flow meters. After cleaning in the apparatus (ABC), the wastewater is sent for final purification on a 8 L biofilter using non-adapted activated sludge grown on a simulated urban runoff with COD = 350 mg / l. The amount of sludge mixture used is 2 liters.

 The test results, as well as a comparison of the proposed method with the known are given in table. 2, 3.

 Studies have shown that when treating wastewater of paint and varnish production by the claimed method, it is possible to achieve almost complete purification from organic impurities such as phenols, soluble ethers, alcohols, and completely eliminate mechanical impurities.

 Carrying out the proposed cleaning method allows to reduce the processing time to several seconds compared with 2-4 hours in known methods. Provides continuous cleaning at high performance, simplifies the flow chart. It is possible to automate the cleaning process. Electricity consumption at the cleaning stage is reduced by 3 times. (56) 1. USSR author's certificate N 1301788, cl. C 02 F 1/72, 1985.

 2. USSR author's certificate N 592761, cl. C 02 F 1/72, 1976.

 3. Kulsky L. A. Fundamentals of physico-chemical methods of water treatment. M., 1962, p. 63.

 4. Copyright certificate of the USSR N 610797, cl. C 02 F 1/48, 1976.

Claims (1)

METHOD FOR WASTE WATER PURIFICATION FROM ORGANIC IMPURITIES, including magnetic field treatment in a layer of ferromagnetic particles in the presence of hydrogen peroxide, characterized in that the wastewater is passed through a magnetic field with a space velocity of 15 - 25 m ³ / h while hydrogen peroxide is introduced into the stream with aluminum sulfate, taken at a ratio of 15 ÷ 20/1, moreover, the mixture is added to waste water in an amount of 0.03 - 0.05 g / l.

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