Tuesday, February 19, 2013

Catastrophic Leak of Molten Aluminium Lithium......



Molten aluminium water explosions are common in the aluminium industry. Over the past decade, direct chill vertical casting equipment manufacturers have used automated systems that minimize the risk of the casting operator. Nevertheless explosions still occur, workers get injured or worse. Molten aluminium lithium explosions are significantly greater in force than that of conventional molten aluminium alloys. A number of variable affects the explosion potential, including the lithium content of the alloy, temperature of metal, and depth of water, etc.. Here is a recent story of a molten metal spill:

On November 30, 2012 firefighters were called to a factory in Birmingham, United Kingdom after there was a "catastrophic leak" of molten chemicals. 

Crews were called to Alcoa in Kitts Green at about 8:30 PM to reports molten aluminium and lithium had escaped a furnace.

Staff at the factory threw cold aluminium ingots into the substance to cool it down while firefighters poured sand over the secondary fires it had started. 

The leak was contained to the concrete pit where the furnace was located. 

It's thought the leak had been triggered by the failure of a porous plug on the furnace. A watch commander at Sheldon fire station, described the leak as "catastrophic". He said an internal investigation would be carried out.

An unrecognized hazard in many aluminium plants is the concrete pit under furnaces. A safety expert once told the APSB that "the probability of molten metal getting in the pit under a furnace is low, but if it does there is a high probability of a catastrophe."

History has shown that these pits have been the source of several horrific molten aluminium explosions in the past. For instance the August 20, 2007 explosion that occurred at the Binzhou Weigiao Aluminium Company's cast house. 

16 workers were killed, and 64 injured initially.  Later reports listed the total deaths to be over 50 workers.
The final report by the Chinese Government blamed worker errors and equipment design. Unfortunately, the damaged was so extensive, little was left of the facility, the casting equipment and furnaces to properly conduct a root cause investigation. What is known is that a large amount of molten aluminium escaped a furnace. Where that molten aluminium went is not known. One theory is that the molten metal either went into the casting pit and exploded or went into the pit under the furnace and came into contact with water and exploded. Using past molten metal incidents as a reference, it is more likely that the molten metal emptied into the pit under the furnace as well as the casting pit.

The Chinese Government's report made several recommendations. Such as that all new plants and equipment use a certain organic coating where ever molten aluminium may come into contact with concrete or steel. The organic coatings that the Chinese government recommended for new plants was Wise Chem. Unfortunately, the use of "new plants and equipment" have resulted with existing plants not applying safety pit coatings. Explosions have occurred in Chinese Cast houses, which could have been prevented with the use of Wise Chem.

Binzhou Weigiao explosion has changed our industry for the better. Most new furnaces installed now have their pits coated with Wise Chem prior to startup. 

Question for readers

Have you ever been around a molten aluminium water explosion?

7 comments:

Anonymous said...

I have, but on purpose. As you know, Alcoa has ran various molten metal explosion testing programs. Some sponsored by the Aluminum Association. I was on the late-90s research team and managed the Explosion Bunker at the Alcoa Technical Center. Saw plenty explosions and since then have been on several incident investigating teams. The Aluminum Assoc.'s Guidelines are chock-full of good information for those interested in casthouse safety. The Guidelines were put together by people with hands-on knowledge and experience, not a "ghost" technical writer. Dave Leon, retired Alcoa

Unknown said...

These furnaces are commonly useful for commercial and in-house heat treating processes. High-temperature salt baths create an oxygen-free process of heating steels, and thus drastically decrease decarburizing, oxidation, and scaling work.

For More Info :- pit furnace manufacturer

Thanks.

Nithya said...

Thanks for sharing the useful information..

aluminum casting alloys

Unknown said...

Nice Blog..

aluminum casting alloys

Unknown said...

it's very danger ,our factory also has 4 Ton center furnace in house

aluminum die casting

JLSOVENS said...

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JLSOVENS said...

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