'Unprecedented' corrosive chemical leak at Vietnam alumina refinery

By Bach Duong   August 3, 2016 | 10:40 pm PT
The latest in a series of environmental fallouts has hit the Central Highlands.

Workers at the Nhan Co alumina plant in Vietnam’s Central Highland province of Dak Nong last week discovered a broken pipeline containing the corrosive chemical sodium hydroxide.

Some 9.6 cubic meters of sodium hydroxide has leaked from the plant, posing serious environmental threats to nearby residents.

Sodium hydroxide is used at high temperatures to wash aluminum ore, also known as bauxite. 

Alumina is a white powder made from bauxite ore for producing aluminium. It sits between bauxite and aluminum in the light metal's production process chain.

The leaked chemical has reportedly penetrated an area of 600 square meters, and some of it has been flowing into a stream, state media reported.

The incident occurred on July 23 when a pipeline burst as the sodium hydroxide was being pumped to the production area.

“What has happened is unprecedented and uncontrollable,” said the project's management board in a report.

Chinese contractor Chalieco had been trialing the system for about a month before the chemical leak was detected.

After seeing a large number of dead fish in Dak Cao Stream, local people waded in to remove them, but experienced itchiness and a burning sensation on their skin.

The plant, along with the Chinese contractor, has pledged to clean up the damage caused by the leak and review the plant's operations to prevent a similar incident from occurring in the future.

In 2008, Vietnam’s largest coal producer, Vinacomin, signed a contract with Chinese company Chalieco to build a $460 million alumina plant in the Central Highlands.

The alumina plant, with an estimated capacity of 600,000 tons of alumina a year, is part of a bauxite and aluminum complex 300 kilometers northeast of Ho Chi Minh City.

Vinacomin has so far invested about VND13.4 trillion ($1.14 billion) in the project.

Vietnam's bauxite ore reserves are estimated at between 5.6 billion and 8.3 billion tons, the world's third-largest after Guinea and Australia, and mostly unmined, according to a report by the U.S. Geological Survey.

Vietnam has said it needs about $15.6 billion to invest in major bauxite and alumina refining projects by 2025 to extract its vast bauxite ore reserves, most of them in the Central Highlands.

 
 
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