Flash explosion in acidic water storage tank
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This post was last edited by Clauspolunit on 2009-9-7 at 16:45. Recently, during the commissioning of the acidic water stripping unit at Dushanzi Petrochemical, flammable gases from the acidic water degassing tank entered the acidic water tank, which led to a flash explosion inside that tank while work was being carried out there; as a result, the tank was damaged. During the maintenance of the Dalian Xitai acidic water stripping unit in 2007, a flash explosion occurred while the construction crew was working with open flames at the top of the tank, due to water remaining inside it. In 2005, a flash explosion occurred in an acidic water tank at Daqing Petrochemical, resulting in a serious accident that caused many deaths and injuries. Therefore, I urge everyone not to underestimate the safety management requirements when working with acidic water tanks; they should be treated as dangerous as gas tanks.
It is difficult to completely displace the gas and hydrogen sulfide from inside acid water tanks; especially since hydrogen sulfide is heavier than air, dead zones can form, which increases the risk of flash explosions. It must be given full attention.
It is difficult to completely displace the gas and hydrogen sulfide from inside the acidic water tank; it is best to use water pressure to remove the flammable gases before starting work
Under no circumstances should this phenomenon be taken lightly; it must be given serious attention!
The raw water tank of the wastewater stripping unit contains volatile hydrocarbons and condensed oil; it is classified as a Class 1 explosion-proof area, and open-flame operations are strictly prohibited there. It is difficult to achieve satisfactory results unless the sediment inside is thoroughly cleaned ； Moreover, low water storage and excessive internal space are also among the conditions that lead to flash explosions.
When performing hot work inside an acidic water tank, the tank must be completely isolated from the system; the contents of the tank should be emptied, and it should then be purged with nitrogen before hot work can proceed. There definitely won’t be any flash explosions.