Digestors at Aluminum Refinery

Corpus Christi, Texas, USA

In this stage of the aluminum refining process, bauxite ore is mixed with a very strong alkalai (sodium hydroxide) to separate the alumina from impurities, which include dirt, silica, mercury, and other trace metals.
This refinery reported releasing almost 1,300 lbs of mercury and 315,000 lbs of lead into the environment annually up till its closure. A combination of weak demand, and oversupply of aluminum from China reduced the sales from this refinery, which was then purchased by a Swiss multinational metals company. When the labor contract expired in 2014, workers and management could not agree on a renewal, and the plant was closed.

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