The method of purification of gases from nitrogen oxides

 

(57) Abstract:

Usage: in industrial ecology. The inventive method provides for the treatment of gaseous emissions containing nitrogen oxides in alkaline solution in the field of ultrasonic vibrations.

The invention relates to industrial ecology and can be used when cleaning gas emissions of oxides of nitrogen.

A known method of purification of gases from nitrogen oxides, providing for the processing of aqueous alkali solution in the presence of hydrogen peroxide.

The disadvantages of this method are complex composition used for gas cleaning fluids and shallow depth cleaning.

The technical result of the invention is the simplification of the composition of the liquid used for the exclusion of her hydrogen peroxide and increase the depth of treatment.

This result is achieved in that in the method of cleaning gases from nitrogen oxides, providing them with treatment with an aqueous solution of alkali, according to the invention the treatment is carried out in the field of ultrasonic vibrations.

This eliminates the need for the introduction of liquid hydrogen peroxide and increase the depth gazzola, fed to the purification of aqueous alkali solution in the field of ultrasonic vibrations. When spraying liquid it is carried out by ultrasound to transmit ultrasonic waves drops of the dispersed liquid stream. When the bubbling gas emissions in the cleaning liquid ultrasonic vibrations convey cleaning fluid through the vessel wall or through a waveguide or create them directly in the liquid one of the known methods. Under the action of ultrasound in water are formed atomic hydrogen and the hydrogen peroxide, the first of which is an active reducing agent, reacts with the lower oxides of nitrogen, resulting in they are reduced to nitrogen and water is formed. Hydrogen peroxide as an active oxidizing agent, oxidizes lower oxides of nitrogen to the top with water. In the alkaline environment of higher nitrogen oxides to form water-soluble salts, nitrogen and water. That is, compared with the closest analogue somewhat increases the release of nitrogen and slightly lower output of nitrates and nitrites. At the same time, the ultrasonic vibration is provided, as is known, the acceleration of mass transfer processes and chemical reactions, resulting in increasing both the speed and depth cleaning is zhota when processing the same gas emissions on the same installation using only alkaline solution was 28% when using alkaline solution with hydrogen peroxide was 75% when using alkaline solution in the field of ultrasonic vibrations was 78%

Thus, the proposed method eliminates the necessity of introduction of hydrogen peroxide in the reaction mixture and to increase the depth of gas purification.

The method of purification of gases from nitrogen oxides, providing for the processing of aqueous alkali solution, wherein the treatment is carried out in the field of ultrasonic vibrations.

 

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2 cl, 1 tbl

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EFFECT: the invention ensures simplification of the production process of the effluent gases purification from nitrogen oxides, to increase the level of purification of the gases in the broad range of the temperatures of the purified combustion products, to decrease significantly the share of the secondary contaminant - ammonia in the purified gases.

5 cl, 2 ex, 1 dwg, 2 tbl

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3 cl, 2 ex, 6 tbl

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3 cl, 1 dwg, 1 tbl

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13 cl, 4 tbl, 3 ex

FIELD: cleaning waste flue gases of tubular furnaces used in power technological plants of ammonia production process from nitrogen oxides.

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2 ex

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2 cl

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8 cl, 2 tbl, 3 ex

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4 cl, 3 tbl, 2 ex

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EFFECT: increasing of the purifying index of effluent gases.

3 cl, 4 ex

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