| Case Name |
Fire caused due to sudden rupture of a buffer drum of a compressor at a light fuel oil desulfurization unit |
| Pictograph |
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| Date |
January 28, 1994 |
| Place |
Sakaide, Kagawa, Japan |
| Location |
Refinery |
| Overview |
On January 28th, 1994. Switching to the spare machine of a hydrogen gas compressor of a light fuel oil desulfurization unit was carried out at a refinery in Shikoku. When starting and pre- inspecting of the spare machine were conducted, no problems were found. The buffer drum at the recycle side of the compressor started operation after switching. Then it ruptured and a fire occurred. The accident was caused by stress corrosion cracking generated in the buffer drum, which had been used for a long time in a wet hydrogen sulfide gaseous environment. Sufficient consideration was necessary for equipment used under such conditions from the viewpoints of materials selection, design, and maintenance. |
| Incident |
Three compressors (A,B,C) fed hydrogen gas for desulfurization to the reactor at a light fuel oil desulfurization unit, and two of them were usually used. A and B were used on the day of the accident. Machine A was in a bad condition and switching to standby machine C started. During the work, the buffer drum of a recycle side of machine C ruptured, and a fire occurred. |
| Processing |
Manufacture |
| Individual Process |
Reaction |
| Process Flow |
Fig3.Unit process flow
|
| Chemical Reaction |
Other |
| Substance |
Hydrogen, Fig4 |
| Type of Accident |
rupture, leakage, fire |
| Sequence |
In October, 1972. Operation of the unit started.
On January 28th, 1994, about 08:30. The group head directed operators to switch from machine A to machine C.
About 09:00. An inspection before starting machine C was carried out, and no abnormality was found.
About 09:10. Operation before starting machine C was carried out. There were no abnormalities.
About 09:15. Switching of a load at the recycling side to machine C from machine A was carried out, and the field operation ended. At this time, a sharp decrease in the flow rate was noticed by a control operator in the control room. A rupture and a fire occurred when the control operator asked the workers to return the load using the wire broadcast system.
10:04. The fire was confirmed to have been extinguished. |
| Cause |
The ruptured buffer drum had been operated in a wet hydrogen sulfide gaseous environment for a long time. Stress corrosion cracking gradually proceeded due to the hydrogen sulfide environment, and a rupture occurred under usual operation pressure. |
| Countermeasures |
Enhance inspections. |
| Knowledge Comment |
It is necessary to improve material choice and design, as well as maintenance of such equipment used under severe conditions such as a wet hydrogen sulfide gaseous environment for a long time. |
| Background |
It is a basic fact that stress corrosion cracking was generated at the buffer tank by hydrogen sulfide. Imperfect maintenance, design, materials selection are related. The operation environment had not been checked by operators and a maintenance staff. Therefore, it could not be judged whether the selected material was suitable or not. |
| Reason for Adding to DB |
Example of burst caused due to stress corrosion cracking under severe conditions |
| Scenario |
| Primary Scenario
|
Poor Value Perception, Poor Safety Awareness, Inadequate Risk Recognition, Organizational Problems, Poor Management, Poor Maintennce Management, Planning and Design, Poor Planning, Poor Repair Planning, Usage, Maintenance/Repair, Inspection, Failure, Large-Scale Damage, Rapture, Secondary Damage, External Damage, Fire, Bodily Harm, Injury, 2 person injured, Loss to Organization, Economic Loss, Direct Monetary Damage 69 milion yen
|
|
| Sources |
High Pressure Gas Safety Inst. of Japan. High-pressure gas protection overview. pp.146-147(1995).
Fire and Disaster Management Agency. Major examples of accidents. Rupture of buffer drum attached to hydrogen gas compressor of light fuel oil desulfurization unit. Accident examples of dangerous materials. pp.112-115.
Assoc. for Safety Techniques of Dangerous Materials. Accident examples of dangerous materials. Dangerous material accident case seminar. pp.129-130(1996).
|
| Number of Injuries |
2 |
| Physical Damage |
Debris dispersed within a radius of 29 m. Complete destruction of a slate roof of a high-pressure gas compressor house. A hydrogen compressor was damaged. A steel floor grating was damaged. A forest reserve was destroyed by fire. Walls of an analysis house using RI were damaged. |
| Financial Cost |
¥ 69 million. (Accident examples of with dangerous materials) |
| Multimedia Files |
Fig2.Photograph of scene
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Fig4.Chemical formula
|
| Field |
Chemicals and Plants
|
| Author |
DOBASHI, Ritsu (School of Engineering, The University of Tokyo)
TAMURA, Masamitsu (Center for Risk Management and Safety Sciences, Yokohama National University)
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