A Flooded Column Collapses as Water Is Being Drained from the System

A Flooded Column Collapses as Water Is Being Drained from the System 

This case history has been reproduced with the kind permission of the American Institute of Chemical Engineers. Copyright 1993. It first appeared in Don t Become Another Victim of Vacuum, Chemical Engineering Progress, 1993. All rights reserved. [5] 

The stainless steel stripper column stood about 82 ft. (25 m) tall, which included a column skirt base of about 15 ft. (4.6 m) tall. The stripper collapsed in the lower 9-ft. diameter (2.7 m) section just below the conical transition section that tapered down to connect with the upper 5A ft. (1.7 m) diameter section. The vessel was designed to operate about 5 psig (34.5 kPa gauge) and was mechanically rated for about 25 psig (173 kPa gauge). 

At the time of the incident, the operating team was preparing to simulate operations by circulating water in the system. Shortly after midnight, operators noticed water coming from the reabsorber vent. Pre-op engineers concluded that water had flooded both the 

The crew decided to open the drain valves on the 3-inch (7.6 cm) suction lines from the reabsorber and stripper bottoms pumps. About an hour later, when the level in the reabsorber dropped to about 75 percent, the crew closed the suction drains valves. They started the feed stripper bottoms pump, creating an even greater partial vacuum as the water stream was routed to the reactor. About 10 minutes later at 1 15 A.M., an employee observed the column slowly start tilting, and then toppling from the vertical position. By the time the stripper dropped to a 45-degree angle, the eyewitness reported it was falling very fast. 

FiGURE 3-5 A Stripper column collapses. Courtesy of Guido DeJesus. 

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A flooded column collapses as water is being drained from the system... 

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