Home   Browse database   Free examples   Contact us   Login
Related links
11542 Chemical accident in Japan with chemical n.o.s.
Go back to the accident listing

You do not have a membership or you are not logged in
Become a member
General accident information
Class/Quality * * *
Year 1970
Summary Self-ignition and explosion
Due to too high concentration
Of acetaldehyde in reaction
Country J
Chemicals Acetaldehyde, Aldehydes, Aldehydes, Aldehydes,
Chemical n.o.s., Manganese acetate (t.hydrate), Manganese acetate (t.hydrate), Oxygen (gas),
Oxygen (gas)
Cause Human-failure
Fatalities/Injuries 0 / 0
Occurrences or events Draining, Explosion, Fill, Fire,
Fire fighting/Emergency response, Heating, Human-operations, Ignition,
Maintenance, Overheating, Run-away-reaction, System-operations,
Wrong-action, Wrong-composition
Full accident information 
download accident report Click here to view a document containing the full accident information

Country: JAPAN (J)
Date : 1970 0515

At the starting time of the reaction after the termination of the induction period, the concentration of aldehyde was about 5.5% (the normal concentration is about 2%). The rate of oxidation of the aldehyde by oxygen is known to be proportional (1.5:1) to the aldehyde concentration.
Normally, outer-circulating liquid returns the top of the reactor column and falls down in a droplet or mist form (that is, droplet containing catalyst). It is presumed that a rapid reaction started at the top of the column, then the temperature of thermal insulated droplets increased, the reaction rate was accelerated, and, as a result, the temperature reached the ignition temperature of the aldehyde (175/C). That is, the accident can be mainly attributed to an excessively high concentration of aldehyde.

Lessons learned (safety measurements)
The level indication improved and provided with a alarm.
Limitation of the aldehyde concentration in the reaction liquid.
Clarification of work norm.

Une explosion et un incendie se produisent dans un complexe chimique fabriquant de l'acide ac??tique. A la suite de l'oubli de l'adjonction d'un solvant dans un r??acteur, la concentration en ac??tald??hyde est devenue trop importante (5.5% pour 2%). L'??l??vation de la temp??rature a amen?? le produit ?? son point d'auto-inflammation et la colonne de r??action a explos??. Le r??acteur est partiellement d??truit, ainsi que des fen??tre des maisons voisines.

Home   Browse database   Free examples   Contact us