System of increasing steam productivity of low-temperature exhaust heat recovery in acid production from sulfur

Abstract

The invention discloses a system of increasing steam productivity of low-temperature exhaust heat recovery in acid production from sulfur. The system includes: a high-temperature absorption column, asteam generator, and a dry absorption section, etc. The steam generator is arranged around a mixer to absorb heat generated therefrom for producing steam and outputs the steam via a pipeline; the dryabsorption section is connected to the high-temperature absorption column and the mixer and is used for absorbing SO3 gas and water in air to produce sulfuric acid; the sulfuric acid then is deliveredto a secondary sprinkling device of the high-temperature absorption column and a finish product acid output pipeline; the sulfuric acid diluted in the mixer is delivered to the dry absorption sectionby means of a primary sprinkling device in the high-temperature absorption column. In the application, the source of secondary sprinkling acid in the secondary sprinkling device in the high-temperature absorption column is changed, and a connection pipeline between the mixer and a dry acid trough in the dry absorption section is optimized, so that acid mixing mode in the dry absorption section ismodified. The system simplifies the structures of the devices and greatly improves the steam productivity in summer.

Description

technical field [0001] The invention relates to the technical fields of chemical industry, energy saving and environmental protection, in particular to a system for improving the steam production rate of low-temperature waste heat recovery of sulfuric acid production. Background technique [0002] The sulfuric acid production process includes three processes: the combustion of sulfur-containing raw materials, the oxidation of sulfur dioxide and the absorption of sulfur trioxide. These processes are accompanied by the release of a large amount of chemical energy. 56%, 19% and 25% of the heat of reaction. Most of the sulfuric acid production plants recycle the high- and medium-temperature heat energy generated by the combustion of sulfur-containing raw materials and the oxidation of sulfur dioxide as much as possible, while the low-temperature heat energy in the drying and absorption system is generally removed by circulating cooling water. Wasted. [0003] In order to make ...

AI Technical Summary

Problems solved by technology

However, due to the phenomenon of acid stringing between the mixer and the dry acid tank in the above system, the low-concentration sulfuric acid in the dry acid tank is introduced into the dry acid tank, resulting in a decrease in the amount of water added during the dilution process of the mixer, which further leads to a decrease in the heat released during the dilution process, eventually causing The problem of low steam production in low-temperature waste heat recovery of sulfuric acid production

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