Process for preparing sulfuric acid by sulfurated hydrogen stepwise reaction

Abstract

The invention provides a process for preparing sulphuric acid by the step reaction of sulfureted hydrogen. Raw material of sulfureted hydrogen and part of air are burnt incompletely at the front part of an air cooled reactor through a burner, generated mixing gas and cooled air entering along the internal wall of the reactor are burnt further, the sulfureted hydrogen is completely converted into sulfur dioxide; the sulfur dioxide passes through a waste heat boiler to generate high pressure steam for recycling the heat quantity and enters a convertor; the sulfur dioxide is catalyzed and oxidized into sulfur trioxide in a converter by adopting the way of subsection air sharp quenching; and the sulfur trioxide gas is absorbed into a concentration tower, higher than 97 percent sulphuric acid is obtained at the bottom of the tower and the tail gas at the top of the tower is purified and discharged.

Description

1. Technical field [0001] The invention provides a process for producing sulfuric acid by stepwise reaction of hydrogen sulfide, which belongs to the field of coal chemical industry. 2. Background technology [0002] At present, the hydrogen sulfide produced by the coal chemical industry is mainly produced by the Claus method, that is, the hydrogen sulfide is firstly oxidized to sulfur dioxide by air, and the H 2 S / SO 2 Under the condition of the molar ratio of 2:1, it reacts with the catalyst to generate sulfur; in order to prevent environmental pollution, it is necessary to build a huge tail gas treatment device, so the construction investment and production cost of the sulfur production device are very high. However, more than 90% of the sulfur produced at such a high cost is used as a raw material for the production of sulfuric acid. If hydrogen sulfide is used to directly produce sulfuric acid, many complicated processes can be saved, and the production cost of sulfur...

AI Technical Summary

Problems solved by technology

The Kangkaite method is suitable for producing sulfuric acid from low-concentration hydrogen sulfide. Two-stage Venturi condensers, condensation towers, wire mesh and fiber demisters are used to recover sulfuric acid to obtain 93% concentrated sulfuric acid. The process is complex, the process is long, and the concentration of sulfuric acid is low.

The WSA-2 wet decomposition contact method is suitable for treating 40%-50% hydrogen sulfide gas at a high concentration. The combustion of hydrogen sulfide and the oxidation of sulfur dioxide are carried out in the same reactor, and the process is relatively short. However, in order to prevent the reaction temperature from being too high, There are sodium nitrate and sodium nitrite molten salt cooling tubes in the reactor, which greatly improves the operation difficulty and investment

[0004] Since the explosion limit of hydrogen sulfide in air is 5.9%-27.2%, the direct and complete combustion of existing high-concentration hydrogen sulfide and air just falls within the explosion limit range of hydrogen sulfide in air, so it is difficult to use hydrogen sulfide to directly prepare sulfuric acid process

Images