Prerequisites for the long-term stable operation of sulfuric acid production plants

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This post was last edited by in the blink of an eye on 2019-12-13 08:11. After working in this industry for so many years, I’ve seen that a large portion of the maintenance work carried out in most sulfuric acid plants is aimed at addressing the problem of acid accumulation in the dry absorption towers – though it’s only a temporary \"solution\". The dry mesh belt causes acid corrosion in the downstream hot and cold exchangers, while the suction demister causes acid corrosion in the downstream intermediate hot and cold exchangers. In systems with heat and cold exchange as well as intermediate heat and cold exchange, once the tube bundles are corroded and punctured, causing internal leakage, the conversion rate will inevitably be compromised. When the tubes leaking at the hot and cold exchangers as well as the intermediate hot and cold exchangers are sealed due to parking, it is found that the heat exchange area decreases, and the self-heat balance is affected as a result. This creates a cycle: acid in the dry absorber mist eliminator → internal leakage in the downstream and intermediate heat exchangers → decreased conversion rate → inspection and repair of leaks in the heat exchangers plus catalyst replacement → increased conversion rate → acid in the dry absorber mist eliminator → internal leakage in the downstream and intermediate heat exchangers → decreased conversion rate → inspection and repair of leaks in the heat exchangers plus catalyst replacement → reduced heat exchange area in the heat exchangers → disruption of the thermal balance in the conversion process → inability to maintain the temperature in the subsequent beds → decreased conversion rate → replacement of the dry absorber mist eliminator → acid in the dry absorber mist eliminator → internal leakage in the downstream and intermediate heat exchangers → (cycle continues)