Tan Rai bauxite is running at capacity, is the amount of red mud exceeding the reported level?

Tan Rai alumina factory (Lam Dong) has been running beyond its design capacity. Is the red mud exceeding the level reported to the Ministry of Natural Resources and Environment ?

Packaging aluminum at Lam Dong Aluminum Company - Photo: MV

On November 7, Lam Dong Aluminum Company, the operator of the Tan Rai bauxite-aluminum complex in Bao Lam district related to the discharge of red mud, said that due to increased demand from domestic and foreign partners, in the past two years the Tan Rai alumina plant has been operating beyond its design capacity.

Exceeding design capacity of 90,000 tons/year

Specifically, the factory's design capacity is 650,000 tons/year, but in 2023 the output of the alumina factory increased to 740,000 tons; in 2024, the expected output is equivalent to that of 2023.

Tuoi Tre Online reporter discussed with Lam Dong Aluminum Company whether the increased capacity compared to the design and the increased supply of alumina will lead to excess waste (red mud) generation?

Mr. Nguyen Van Tinh, deputy head of the technical department of Lam Dong Aluminum Company, said that the capacity has been increased to meet actual production needs. The technology and production lines in general have not changed, but there have been adjustments in the stages of ore selection and waste treatment.

According to Mr. Tinh, specifically, the refined ore rate reached 54% compared to the expected 49%. Improvements in the ore selection stage helped the total amount of crude ore exploited not to exceed the level reported to the Ministry of Natural Resources and Environment.

Red mud does not increase but... decreases

Regarding the question of whether the amount of red mud waste will increase compared to the plan, Mr. Tinh affirmed that it will not increase but decrease.

“We adjusted the extraction and crystallization method when producing alumina. Therefore, the actual alumina yield increased by over 84%. The waste ratio decreased accordingly. The amount of red mud decreased even though the factory’s capacity and output increased,” said Mr. Tinh.

Currently, the alumina plant has used up almost all 7 red mud tanks after nearly 12 years of operation.

In the next two months, storage tank No. 8 will be put into use. After that, Lam Dong Aluminum Company will invest in dry waste technology to reduce the amount of waste in the alumina production process.

Red mud is an environmental safety concern

Red mud is the name of the waste product of the technology applied in the process of refining bauxite to produce aluminum.

All the chemicals that do not dissolve in this cycle are called red mud.

The red color of the mud is due to the presence of oxidized iron (which can make up to 60% of the mass of red mud). In addition to iron, other major components of red mud include sand, aluminum... and a type of titanium oxide called anatase.

Red mud is very toxic because it has a pH about 1 million times higher than the safe pH. Therefore, red mud is always a safety concern for the environment.

Source: https://tuoitre.vn/bo-xit-tan-rai-chay-vuot-cong-suat-luong-bun-do-lieu-co-vuot-muc-da-bao-cao-20241107164003053.htm