Device and method for absorbing free sulfur trioxide in fuming sulfuric acid through concentrated sulfuric acid

Abstract

The invention discloses a device and method for absorbing free sulfur trioxide in fuming sulfuric acid through concentrated sulfuric acid. The device comprises a concentrated sulfuric acid absorption tower, a circulation groove, an arch channel, an overflow pipe, a circulation acid pump, an exhaust suction fan and a degassing and low-altitude exhaust pipe. The concentrated sulfuric acid absorption tower integrates the functions of acid separation, foam catching, liquid sealing and overflowing, it is ensured that sufficient SO3 gas is sufficiently absorbed and does not escape, and concentrated sulfuric acid is recycled; an automatic water supplementing device ensures the best SO3 absorption effect of the concentrated sulfuric acid; the circulation acid pump is adopted as liquid power equipment, the concentrated sulfuric acid is conveyed to a degassing tower acid distributing device, and after uniform distribution is performed through a packing layer, sufficient reverse flow contact of gas and liquid phases is achieved; the exhaust suction fan is adopted as gas power equipment, free SO3 gas escaping from a 104.5% fuming sulfuric acid storage tank, an acid containing device and an underground tank are sucked into the absorption tower to be sufficiently absorbed, gas reaching the standard is exhausted out, and the sulfur resource comprehensive utilization rate is increased.

Description

technical field [0001] The invention belongs to the field of chemical environmental protection, relates to acid production from smelting flue gas, and in particular relates to a device and method for concentrated sulfuric acid to absorb free sulfur trioxide in 104.5% oleum. Background technique [0002] 104.5% oleum is also called 20% oleum, namely: contains 20% free SO 3 oleum, in the process of storage and acid loading of 104.5% oleum, a large amount of free SO 3 The gas will escape from the top of storage tanks and tank trucks, forming a large amount of acid mist, which will cause serious pollution to the surrounding environment. The dry suction process of the traditional acid system often uses the negative pressure of the outlet flue of the electric demister in the purification process to effectively remove the flue gas. However, 104.5% oleum has particularity. If the traditional method is used for degassing, on the one hand, a large amount of free SO 3 In the degassi...

AI Technical Summary

Problems solved by technology

However, 104.5% oleum has particularity. If the traditional method is used for degassing, on the one hand, a large amount of free SO 3 In the degassing pipeline, the gas easily absorbs water to form concentrated sulfuric acid, corrodes the FRP flue, and causes the degassing pipeline to be blocked; on the other hand, a large amount of free SO 3 The gas will combine with a large amount of water at the outlet of the electrostatic demister to produce acid mist, which cannot be removed in the subsequent process. A large amount of acid mist entering the fan will corrode the impeller and adversely affect subsequent equipment and catalysts, resulting in smoke from the exhaust chimney

Images