Bio mining uses microorganisms like bacteria and fungi to extract metals from ores. It involves two main processes: bioleaching and biooxidation. Bioleaching involves dumping low-grade ore into a heap and soaking it with acid and bacteria, which degrade the ore and release minerals into fluid. This technique is commonly used to extract gold, copper, nickel, zinc, uranium, and silver. The most common microbes used are Thiobacillus and Leptospirillium.

1. Prepared by
Raheela Shabbir

2. Bio mining can be defined as the
extraction of minerals from ores by using
microorganisms. The microorganisms
actually facilitate the extraction of metals
from sulfide /iron containing ores.
Metals solublization process is involved in
bio mining and it is a combination of
microbiology and chemistry.

3. Bioleaching
Bio oxidation
Common metals

4. It is a classic method of bio mining .In this
method low grade ore is dumped into a
heap called leach pile and then soaked
with weak sulfuric acid wash. Then acid
react with the ores sulfide matrix and
encourages the growth of bacterial strain
which start to degrade ore and releases
minerals /metal in fluid form

5. It is widely used for the extraction of gold
from ores this process involves exposing
the ore to bacterial oxidation which
degrades (breakdown) the insoluble pyrite
and arsenic components as it is a precious
metal only removal of interfering metal
sulfides from ore. Actually bio oxidation
leaves metal in solid phase and solution is
discarded.

6. Metals for which this technique is
employed included Copper, nickel, zinc,
uranium, gold and silver.

7. Most common microbes which are used for
bio mining:
Thiobacillus
Leptosprillium

8.  Bio mining is cheaper although it is slower it is also
cleaner.
 Bio mining will become important in future as high
grade ores are becoming exhaustible so bio mining will
become the source of metal extraction from low grade
ores.
 Metals can be extracted from polluted water also by
bio mining such as waste dumps.
 Metals can also be recovered from industrial effluents
such as sulfur reducing bacteria are used to remove
dissolved metals from industrial waste.
 Microorganism are used to pretreat gold.
 Bio mining produces increased yield and less
environmental impacts.

9. Bio mining is slower than other traditional
mining techniques.
It is not applicable to wide variety of ores.
Bio mining lacks complete control thus
leading to inefficient extraction rates .
Acid production is the major problem of bio
mining so solid waste must be disposed of
properly.