""liquid aluminum ... started leaking from the furnace into the basement"

 

Telling a person who bought a new car that eventually it will break down will get you the same response as telling a new aluminium plant owner that their new furnaces will eventually leak. For the sake of this blog, how aluminium plants prepare for the eventual furnace leak that may not happen for years is nevertheless important. Here is a recent story on a furnace leak:

On one evening in the Fall of 2019, the fire brigade pulled out with large equipment for a fire at European aluminium smelter on (an) industrial estate.

According to a spokesperson for the fire service, there was no question of a raging fire. "There is liquid aluminum in the fire and that has started leaking from the furnace into the basement," said the spokesman.

The fire brigade arrived with a powder extinguisher and a cherry picker on site. Because aluminum cannot be extinguished with water, the fire service allowed the aluminum to cool down naturally.

Defensive action (twitter from the fire brigade)

The fire brigade soon announced that all employees were safely outside. There was also no danger to the environment. "But we expect that we will be busy for a while," said the spokesman on Sunday evening.

Please note we try to post recent stories but sadly we have such a backlog of incidents most involving injuries and fatalities that some stories keep falling down the list to post. Regardless, we feel every incident can be used as a learning tool to make your workplace safer. We are ecstatic no one was injured in this incident. No doubt the smelter had the necessary fire extinguishing agent in stock to prevent the molten metal from flowing, and contained it by making a dam with the bone ash, class d- fire extinguishing agent, etc.

Furnaces leak, do all furnaces leak? Not all but in our experience when we talk to plants about furnace leaks the comments range from “well you should have been here 6 months ago” to “why would we care now when the furnace is brand new”. It really is two different extremes. We do not have to convince the plant that just had a furnace lining failure to the hazard. But, we do have to convince the new plant owner. Sometimes we are successful, and sometimes we are not. If your workplace has a furnace(s) it is important to ask your personnel “Where will the molten metal go if we have a furnace leak?” Then follow up with “Can the molten metal come into contact with moisture or bare steel, stainless steel or concrete substrates?” The answer to the second question is commonly “yes”. Then your plant needs to be proactive and paint all surfaces where molten metal will flow with Wise Chem to prevent these potential areas from generating an explosion. The other reason these areas can easily generate an explosion is the presence of chemical salts. Chemical salts are throughout a plant that handles molten metal. Chemical salts can be brought into a plant through two methods. First is on the bottom of worker’s boot during the winter (e.g. road salt). Second, is from the use of fluxes in the melt process. These chemical salts attract water on a molecular level. Any localized areas that are contaminated with chemical salts can be a source of an explosion if contacted by molten metal. The process of chemical salts attracting moisture generating an explosion is also found when hand tooling placed in molten metal generates an explosion. All too often the hand tooling is improperly stored (touching the concrete floor) where chemical salts get attached to the surface. An explosion results.

Aluminium Insight magazine had an article on this topic in the past. It can be found here.

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