Acid tank collapsed

Event 9 Fire/Explosion—Sulfur dioxide and sulfuric acid. Motiva Enterprises, LLC, Delaware City, Delaware (July 17, 2001). Collapse of a spent sulfuric acid storage tank (more than 250,000 gallons) triggered releases from nearby tanks, killed one contract worker, and caused a large fish kill. Other commonly bermed tanks were immersed in concentrated sulfuric acid for several days until they could be drained, but they did not fail ("News Link" Environmental 2008). 

I— Leaks through acid brick lining or floor. (Detected by holing of steel tank, or wet spots, discoloration, or collapse of concrete.)... 

Indeed, PAAc cryogels coupled with a bromate oscillator oscillated between swollen and collapsed states [31]. The reactions of bromate, sulfite, and ferrocyanide ions were conducted in an open continuously stirred tank reactor. Four feed solutions (potassium bromate, sodium sulfite, potassium ferrocyanide, and sulfuric acid) were supplied continuously to the reactor, during which the pH of the reaction solution was monitored as a function of time. The flow rate of the feed solutions is an important parameter in determining the extent of pH oscillations. In Fig. 21, pH versus time plots are shown for four different reduced flow rates k, defined as the flow rate of the feed solutions divided by the reaction volume. It is seen that the pH of the solution oscillates between 6.2-6.9 and 3.2-3.8. The dissociation degree a of a weak electrolyte relates to pH by ... 

Chemkal(s) involved Sulfur dioxide and sulfuric acid Event Welding operations on a catwalk tri ered a fire that propagated into an explosion in the confined headspace of a large storage tank, causing its catastrophic collapse and release of its contents. 

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