Hungary Chemical Mud Spill – A real environmental disaster

Just been following the report in the BBC website about the contents of the mud spill from the aluminium processing plant.

The BBC have been very helpful to include a list of what was contained in the spill; giving the following details.

Aluminium-containing ore, bauxite, is washed at high temperatures in sodium hydroxide. This dissolves the aluminium, which can then be  processed further, but the red sludge is left behind as a waste product. It is this which has leaked from the Hungarian storage reservoirs.

The fact that Hungary thought it was OK to handle the toxins in this way shocks me. Oop, my bad.. it’s Hungary.

The sludge waste contains a mixture of metal oxides. According to MAL Hungarian Aluminium – the company which produced the waste – between 40% and 45% is iron oxide. This gives the mud its characteristic red colour. Between 10% and 15% is aluminium oxide, a further 10% to 15% silicon oxide and there are smaller quantities of calcium oxide, titanium dioxide and oxygen-bonded sodium oxide.

Which is where I noticed something. Where is the Aluminium Fluoride?

But let me explain. The process of transforming the raw bauxite ore using sodium hydroxide is the “Bayer process” and it creates alumnia (aluminium oxide). This is the raw material used to produce aluminium metal via the electrolytic Hall-Héroult process. The process in use at the facility in Ajka, Hungary.

The Hall–Héroult process involves dissolving alumina in molten cryolite and then electrolysing the solution to obtain pure aluminium metal.

In order to lower the melting point of the witches brew of cryolite-alumina you need to add our special ingredient Aluminium fluoride (AIF3). Cryolite, incidentally, is sodium hexafluoroaluminate.

Now during the electrolytic process gas is produced. Most of it is CO2 (happy trees) but some of it is the VERY nasty Hydrogen Fluoride (HD). This stuff is so terrible it can etch glass!

So how do we deal with it? Well, it’s neutralised to it’s sodium salt level, sodium fluoride. Which can then be collected and some of it used in the process.

However, most is generated as a waste product and I would presume would have thought it would have gone in the rest of the chemical dump… as nobody gave a crap about what was in there.

Except, that’s NOT where it’s gone. Because this highly toxic compound has another destination. Your water.

Because sodium fluoride is the byproduct of aluminium smelting that’s added to your drinking water in order to “improve dental hygiene”. So I bet you are happy about that.

“The sludge is a strong alkali, meaning it will cause burns when it comes into contact with the skin, and can damage lungs and the digestive system if it is ingested. This may cause death.”

May? Four people have already died and the toxicity will only affect greater numbers of people in the future.

One of the rivers affected has been treated with chemicals – calcium and magnesium nitrates – to try to counter the alkaline effects.

In a real sense, they are just trying to make the brew more manageable in terms of clean up. It’s not safe by any means. But then the article doesn’t really imply it is.

Next down stream is the Danube and the wildlife reserves in Romania.


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