Case Ditails

Case Name Explosion of hydrogen peroxide due to the change of a feeding line to a vessel at a surfactant manufacturing plant
Date July 26, 1989
Place Sodegaura, Chiba, Japan
Location Chemical factory
Overview Dodecylbenzenesulfonic acid was supplied from a pump at the surfactant manufacturing plant. Hydrogen peroxide water (60%) was charged successively with the same pump as a bleaching agent. An explosion occurred at the pump. Iron rust in the pump triggered a decomposition explosion of hydrogen peroxide. Hydrogen peroxide water had to be charged into the reactor directly.
Incident At a surfactant plant, dodecylbenzenesulfonic acid was charged by a pump into a reactor, and alkylamine was also charged as a bleaching agent. As the pH was 8.8, more dodecylbenzenesulfonic acid was added and hydrogen peroxide water (60%) was supplied as a bleaching agent from the pump. Then, an explosion occurred near the pump.
Processing Manufacture
Individual Process Reaction
Process Flow Fig2.Unit process flow
Chemical Reaction Oxidation (bleaching)
Substance Dodecylbenzenesulfonic acid, Fig3
Hydrogen peroxide, Fig4
Type of Accident Explosion
Sequence Dodecylbenzenesulfonic acid was charged by a pump.
Alkylamine was also charged.
pH was at 8.8.
Dodecylbenzenesulfonic acid was added.
Hydrogen peroxide water (60%) was charged by the same pump.
An explosion occurred near the pump. A fire did not break out at that time.
Cause It is a decomposition explosion of hydrogen peroxide. Hydrogen peroxide had to be charged from the upper part of the reactor, but it was charged by the pump supplying dodecylbenzenesulfonic acid. The hydrogen peroxide possibly reacted with iron rust and others in the pump and caused a rapid decomposition reaction.
Response Fire fighting and chemical fire engine were on standby.
Countermeasures Safety education should be improved.
The safety management system should be reconsidered and reinforced.
Hydrogen peroxide water piping should be disconnected from the pump.
Knowledge Comment There are some cases of accidents due to iron rust reacting with hydrogen peroxide. There are not so many substances that can easily cause a decomposition explosion like hydrogen peroxide. Standards for handling these substances should be established.
Background The accident was caused because the operators did not obey specified operation procedures. Human error seems to be the source of the accident. However, there might have been insufficient education on the procedure and about the danger of the explosive decomposition of hydrogen peroxide, and this insufficient education possibly caused the neglect of operation procedures..
As for the equipment, it was desirable that operation cannot be continued without following the specified operation procedures even if there was human error. High-concentration hydrogen peroxide water should not be brought into a place where iron rust was probably present.
Incidental Discussion High concentrated hydrogen peroxide can easily decompose. It seems that the fact hydrogen peroxide is a powerful oxidizer that generates nascent oxygen with decompression was not instructed.
Reason for Adding to DB Example of accident due to arbitrary judgment
Primary Scenario Insufficient Analysis or Research, Insufficient Practice, Lack of Imagination, Poor Value Perception, Poor Safety Awareness, Insufficient Safety Measure, Misjudgment, Misperception, Mis-Convincement, Neutralization Reaction, Planning and Design, Poor Planning, Poor Design, Regular Operation, Nonobservance of Procedure, Procedure Ignorance, Bad Event, Chemical Phenomenon, Abnormal Reaction, Secondary Damage, External Damage, Explosion, Bodily Harm, Death, Bodily Harm, Injury, Loss to Organization, Economic Loss, Direct Monetary Damage 48 million yen
Sources Assoc. for Safety Techniques of Hazardous Materials, "Cases of accidents with dangerous materials," Cases of accidents with dangerous materials seminar, pp.59-60(1996)
Fire and Disaster Management Agency, Major accident cases, MS manufacturing plant, Explosion of pump (PU-301) and piping, Accident case of dangerous materials. pp.33, 52-53
Number of Deaths 1
Number of Injuries 1
Physical Damage Debris was scattered within a 25-meter radius, a pump was damaged, and piping and building were partially damaged. Three tons of semi-finished goods were damaged.
Financial Cost ¥ 48 million.(Accident cases of dangerous materials)
Multimedia Files Fig3.Chemical formula
Fig4.Chemical formula
Notes Neglect of operation procedure, lack of education and fail-safe procedures.
Field Chemicals and Plants
Author WADA, Yuji (National Institute of Advanced Industrial Science and Technology)
TAMURA, Masamitsu (Center for Risk Management and Safety Sciences, Yokohama National University)