"around 500 kg of liquid aluminum from a smelting furnace leaked"

Worst case scenario of any aluminium plant is if a furnace leaks. In the past furnace leaks range from minor leaks to catastrophic. Some of our largest explosions have occurred when an unexpected release from a furnace occurred. Here is a recent story that thankfully did not result in an explosion. Nevertheless, workers were injured.

During one night during the week of October 28, 2019 around 500 kilograms of liquid aluminum from a smelting furnace leaked from an aluminium company’s workshop in Europe. Six employees blotted the material with powder and were treated with suspected smoke poisoning. Two of them came to the hospital for examination, but were allowed to leave the clinic after one hour, said an authorized representative of the company.

Two of the six employees suspected of smoke poisoning were taken to the hospital. Such an incident that a melting pot burst, was nothing unusual. The cracked graphite crucible would be replaced, then the production could be continued. The Criminal Investigation Department, the Environmental Protection Agency and the Office for Occupational Safety and Health determined later the day that the hall was then cleared again.

A local fireman explained that the fire brigade had been alerted in the night at 23.44 clock. In the factory, the employees had already very prudently tried to contain the danger. The difficulty was that the liquid, very hot aluminum (it melts at around 660 degrees Celsius) had spread on the floor and the hall was heavily smoked with non-hazardous vapors. Four respirator squads advanced into the hall and pushed in air through large fans to squeeze the smoke out. In use were around 50 firefighters from six neighboring fire departments.

We pray that the injured workers recover fully from their injuries.

The crucible leaked 500 kilograms of molten metal that immediately came into contact with a combustible or the metal reacted with the “powder” that was used. We wonder what the powder was. We will reach out to the company and inquire and update this post as needed.

On our plant tours we ask greenfield plants if they have planned for a molten metal release. This question usually is dumbfounds them. Why ? They reply. We respond that even that you have brand new equipment accidental molten metal releases can occur. We know of a plant whose workers placed a reject rolling ingot into a furnace thinking it was ok. They were shocked that a “tidal wave” of molten aluminium came out and made a mess of everything. If not immediately contained the molten metal will flow to the lowest area. Commonly that area is maintenance pits under furnaces, maintenance channels (covered with steel plates) through the factory etc. A number of years ago the Aluminium Insight publication had an article about this topic. It can be found here.

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