Wednesday, August 17, 2016

What will be happened in industrial-scale bioleaching?

What shall be taken into account when starting big-scale bioleaching? Some ideas:

1. A successive set of bioleaching pilots (with increasing size).
2. Transport of gases (O2, CO2).
3. Nutrients (P, N etc.).
4. Temperature.
5. Risk of re-building metal sulfides.
6. Microbial reduction of sulfate (see point 5.)
7. Chemical inhibition of sulfide-oxidizing metabolism.
8. Efficiency of Fe3+ to dissolute nickel.
9. Continuous control of microbial activities.

These are the basic issues. There may be more of them.

Coming back soon...

Monday, August 15, 2016

Bioleaching of Nickel - A Challenging Task

It seems that the retirement doesn't stop any person, dedicated to her/his work, to continue actual questions of her/his profession. My wife has worked as a nurse and still dreams about her work with schoolchildren...and the interests of mine are the questions of environmental and industrial microbiology. Can't help...

Bioleaching of metals from sulfide rocks is a most interesting thing! It happens in natural conditions on an area in Northern Europe where the rock contains sulfides of certain metals. Those bacteria which can perform this bioprocess are unique - they need bot oxygen and carbon dioxide as well as some other nutrients but no organic carbon source for energy at all. They are typically slow-growing microorganisms on the surface of the stone.

How to maintain an industrial-scale bioleaching process in mines where the conditions can be as different as in Northern Finland (cold, moist) and Australia (warm, dry)? This is the main question which I have studied by using scientific literature and results of laboratories (as far as they are public - what they not always are, indeed!), trying to compare different cases.

- More of the basics of bioleaching and cases in coming posts...keep following!