SU1472435A1 - Method of producing hydrogen - Google Patents

Abstract

The invention relates to methods for producing hydrogen by decomposing water in thermochemical sulfuric acid cycles. In carrying out the method of producing hydrogen, which includes mixing sulfur dioxide and water, electrolyzing the resulting solution of sulfuric acid with evolution of hydrogen and sulfuric acid, concentrating it and feeding to the thermolysis of sulfur trioxide, separating the resulting vapor-gas mixture with liberating sulfur dioxide and returning it to the mixing stage , to reduce energy consumption while maintaining the yield of hydrogen and to enable the simultaneous production of production oxygen, sulfuric acid is fed to the thermolysis stage Steam with a temperature of 1200–1250 K and a pressure of 2.5–4.5 MPa is carried out, and the separation of the resulting gas-vapor mixture is carried out in three stages, and the first of them is absorbed by sulfur trioxide with a solution of sulfuric acid from the electrolysis stage, the second is condensed water is cooled by the mixture, and the third is oxygenated by the absorption of sulfur dioxide by water, followed by desorption and return of sulfur dioxide to the mixing stage. 1 tab.

Description

one

The invention relates to methods for producing hydrogen by decomposing water in thermochemical sulfuric acid cycles.

The purpose of the invention is to reduce energy consumption while maintaining the yield of hydrogen and to ensure the possibility of simultaneously obtaining production oxygen.

PRI me R. To produce 2 kg of hydrogen, 64 kg of sulfur dioxide, 116 kg of water from the vapor-gas separation stage and 18 kg of distilled water are mixed. The resulting solution of sulfuric acid is fed to electrolysis. The electrolysis is carried out at 100 ° C.

the hydrogen that was made therewith is discharged as a product, the resulting sulfuric acid solution with a concentration of 50% by weight (consumption 196 kg) is fed to. stage of concentration. The concentration of sulfuric acid is carried out by evaporation of the solution by the products of thermolysis of sulfur trioxide, containing 147 kg of sulfuric acid vapor, 64 kg of sulfur dioxide, 16 kg of oxygen and 1417 kg of water vapor, with direct -. contact streams.

At the same time absorb unreacted sulfur trioxide solution of sulfuric acid. The resulting solution (93 Ma.I.) sulfuric acid (consumption

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1472435.

In the proposed method for producing hydrogen, all stages are carried out under increased pressure. The working pressure and temperature of the processes at each stage are determined by the initial parameters of the water vapor used.

Claims (1)

The effect of water vapor parameters on system characteristics is illustrated in the table. Invention Formula A method of producing hydrogen, which includes mixing sulfur dioxide and water, electrolysis of the resulting solution of sulfuric acid with hydrogen and sulfuric acid, concentrating it and feeding to the thermolysis of sulfur trioxide, separating the vapor-gas mixture obtained with separating sulfur dioxide and returning it to the mixing stage. characterized in that, in order to reduce oxygen-containing oxygen, oxygen is released by means of costs while maintaining the absorption of sulfur dioxide by water at 25 yes and ensuring the possibility of the genus in the production of 16 kg of production time is removed from the cycle. From dissolving sulfuric acid to the stage of sulfurous acid solution, obtained thermolysis is injected by absorption during absorption, sulfur dioxide with a temperature of 1200 is heated by heating up to 150 ° C. Di- 30 1250 K and pressure of 2.5-4.5 MPa, and sulfur oxide in the amount of 64 kg returning the resulting vapor-gas stream to the mixing stage. The water flow of the mixture is carried out in three stages, and in G1510 kg1, obtained by separating the first of them, the vapor-gas mixture is absorbed, divided into two parts by sulfuric acid solution with stat- 116 kg of water is directed to the electrolytic stage. , on the second - mixes, 1394 kg of water is sent to denuse water by cooling the mixture, and oxygen is absorbed into the heat exchanger circuit of the external source of the third, where it is obtained by watering sulfur dioxide with water from the next steam with a temperature of 1225 To pressure and by the desorption and return dioxvda 3 O MPa.10 sulfur per mixing stage. 250 kg) are injected into the thermolysis step with a stream of water vapor with a temperature of 1225 K and a pressure of 3.0 MPa (steam consumption of 1394 kg). The process of dissociation of sulfuric acid into sulfur trioxide and water and the catalytic decomposition of sulfur trioxide into sulfur dioxide and oxygen is carried out in the adiabatic mode, with the degree of decomposition of sulfur trioxide being 0.4. The separation of the vapor-gas mixture of thermolysis products is carried out in three steps. In the first, unreacted sulfur trioxide is absorbed by a solution of sulfuric acid at the stage of concentration. At the second stage, water is condensed from the resulting vapor – gas mixture containing 64 kg of sulfur dioxide, 16 kg of oxygen, 1–510 kg of water vapor, cooling the flow to 250 C. At the third stage, from a gas mixture containing 64 kg of sulfur dioxide and I6 kg TIBNICHY stage thermolysis of sulfur trioxide 1350 3.0 1200 1.0 1200 6.0 Prototype 1 1 23- 1173 4-5 Table continuation Unproductive increase in capital costs for the construction of the plant 30 Increase in cost of compression of production hydrogen 70 Non-productive increase in capital expenditures for the construction of an installation t 50 The decomposition of sulfuric acid is carried out upon contact with air.