What are bioleaching and bioremediation?

Bioleaching

Bioleaching is an effective technology for metal extraction from low-grade ores and mineral concentrate. This is a simple process which can be done using microorganisms such as Mesophiles, moderately thermophilic bacteria, Extremophiles. Bioleaching is a part of Bioremediation.

This process of Bioleaching was used 3000 years ago while recovering copper from mine waters in the Mediterranean area. From then it has been used, but rarely. Recently about 40 plants are using this method to extract copper, gold, zinc, cobalt, and uranium. The organisms used in this procedure are single-celled and undergo chemosynthetic metabolism. They derive carbon dioxide and oxygen from the atmosphere and requires acidic PH.

There are two processes of bioleaching.

• Direct Bioleaching

Indirect bioleaching, minerals which are susceptible to oxidation undergoes direct enigmatic attack by the microorganisms.

• Indirect Bioleaching

In indirect bioleaching, bacteria produce strong oxidizing agent which reacts with metals and extract them from the ores.

Bioremediation

Bioremediation is the process of removing the pollutants from the environment using microorganisms. The microbes are used to remove organic wastes from the environment. This process is also called Biotreatment, Bioreclamation, and Biorestoration.

These microbes used are generally thermophilic anaerobic microorganisms. But these are affected greatly by unstable climatic and environmental factors from moisture to temperature. Bioleaching is a process of Bioremediation.

Type of Bioremediation

• Biostimulation
• Bioaugmentation
• Intrinsic bioremediation