SU1751167A1 - Elemental sulfur production method - Google Patents

Abstract

Use: The method is used in the production of sulfur, as well as for the neutralization of sulfurous waste gases during the coking and semi-coking of coal and shale of metallurgical production. The process is carried out on the catalyst divided into 2 parts, with the ratio of the volume of free space between the parts of the catalyst bed to its volume, clearly, 0.051-M, and with a temperature gradient in the cross section perpendicular to the direction of gas movement not exceeding 15 ° C. The conversion rate is 95-98.4% .1 table

Description

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The invention relates to the field of chemical, petrochemical, metallurgical and other industries and can be used in the production of sulfur, as well as for the neutralization of sulfurous waste gases during coking and poly-coking of coal and shale of metallurgical industries.

The aim of the invention is to increase the service life of the catalyst.

The method is carried out as follows.

The catalytic layer is divided into two parts so that the ratio of the volume of free space - the gap between the parts of the catalyst to the volume of the catalyst is 0.05-1: 1.0, between which the gas mixture is mixed. This separation is due to the fact that in the case of unsteady process management, the high temperature zone is located in the middle of the catalyst bed and occupies about 1/3 of it. It is most efficient to carry out the mixing in the high temperature zone. Going beyond its limits dramatically reduces the efficiency of the process. For ease of mixing, the gap is located in the middle of the high temperature zone. The initial reaction mixture at a temperature of 20–200 ° C is fed to the first part of the catalyst along the gas path, where a partial chemical interaction of hydrogen sulfide and sulfur dioxide is carried out. The partially reacted reaction mixture at the outlet of the first part of the catalyst bed has significant temperature irregularities in the cross section, ranging from 170 to 320 ° C. Such1 temperature drops in the section arise for the following reasons. Condensed zones form near the walls of the reactor, the low temperature in which does not allow reactions to take place with the XX

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Notable speed Structural inhomogeneities of the catalyst layer cause overheating zones in the layer, the passage through which the mixture heats up to a temperature higher than necessary to carry out the reaction.

The presence of a large temperature gradient in the cross section of the flow of the reaction mixture leads to a reduction in the quality of the second part of the catalyst bed near the walls of the apparatus, which reduces the degree of conversion due to gas leakage without reaction along the walls. In addition, in the second part of the layer, zones of local overheating of the catalyst are formed, this accelerates deactivation, and in a number of cases it can lead to thermal destruction and sintering of the catalyst. In order to increase the service life of the catalyst and increase the yield of sulfur between the parts of the catalyst, the reaction mixture is stirred so that the temperature difference in the section perpendicular to the filtration direction does not exceed 15 °.

PRI me R 1. The composition of the source gas 2% H2S, 1% S02, 97% NZ. Input temperature 125 ° С. Gap / catalysis ratio. 0.05. The gas temperature at the outlet of the first part of the catalyst is 250-320 ° C, the temperature at the inlet to the second part of the catalyst is 280-295 ° C. Time between switching 10 min. The degree of conversion is 96.2%, the maximum in the prototype is 94.4%.

PRI mme R 2. Same as in Example 1. The gap / catalysis ratio 1. The temperature gradient at the inlet to the second part of the catalytic layer does not exceed 5 °. Conversion rate 98.4%.

PRI me R 3. The same. as in example 1. The ratio of the gap / catalysis. 0.5 Temperature gradient at the entrance to the second part

the catalytic layer does not exceed 5 °. Conversion Rate 98.0%

Example 4 Same as in example 1. The ratio of the gap / catalysis of 0.02. The temperature gradient at the entrance to the second part of the catalytic layer is 5 °. Conversion rate 95.5%.

PRI me R 5. Same as in example 1. The ratio of the gap / catalysis of 1.5. The temperature gradient at the inlet to the second part of the catalytic layer is 15 ° C. The conversion is 96.1%.

Example 6. Same as in example 1. The ratio of the gap / catalysis. 0.5 Temperature gradient at the entrance to the second part of the catalytic layer 30 ° Conversion rate 94.1%

The results of the experiments are presented in the table.

As follows from the table, with an increase in the temperature gradient above 15 ° C, the yield of sulfur decreases and the lifetime of the catalyst is reduced. Elimination of the temperature gradient according to the proposed method allows to increase the service life of the catalyst by 15-20%.

Claims (1)

Invention Formula The method of obtaining elemental sulfur by reacting hydrogen sulfide with sulfur dioxide on the catalyst by periodically changing the feed direction of the initial mixture with a temperature of 20-200 ° C is also different in that, in order to increase the service life of the catalyst, the catalyst layer is divided into two parts and The process is carried out with a ratio of the volume of free space between the parts of the catalyst bed to the volume of the catalyst equal to 0.05-1: 1 and with a temperature gradient in the cross section perpendicular to the direction of gas movement not exceeding 15 °.