KGF: Heap Leaching and other mining processes
Director: Janaki Nair; Cinematographer: R V Ramani
Duration: 00:23:59; Aspect Ratio: 1.366:1; Hue: 44.981; Saturation: 0.051; Lightness: 0.400; Volume: 0.110; Cuts per Minute: 21.884; Words per Minute: 32.764
Summary: Mining processes outside of the mine are captured here, especially heap leaching which is a way of purifying the raw ore and extracting the mineral, in this case gold, by repeated chemical reactions in the controlled conditions of a plant.
This video also has a couple of interviews with those who used to work in the plant talking about what the future might hold, what plans they have.
Mother Mary with Infant Jesus
Kolar Gold Field, Kolar District, Karnataka
The Semi Commercial Heap Leaching Plant in Kolar is the place where pure gold is extracted from the ore that is taken out of the mines. This plant is run by Bharat Gold Mines Limited in Kolar.
Heap leaching is an industrial mining process that relies on chemical reactions with precious and other metals to extract them from the ore. Heap leaching is one of the older mining methods and requires the treatment of gold with a leach solution, that will undergo a chemical reaction with gold to create a compound. This is then treated with zinc to yield pure gold.
The stages of heap leaching
require that the mined ore is reduced to small chunks that is then watered down with the leach solution (usually sodium cyanide in the case of gold). The solution percolates through the heap of crushed ore to slowly extract the valuable mineral, and this can in the case of gold, take two to three months. Then the leach solution in which gold has dissolved is then treated further to extract the gold, and also other metals or minerals that might be in the ore. The leach solution is recycled to treat more mined ore. Heap leaching does have several environmental and toxic dumping consequences.
The chemical reaction in the case of gold for extraction via the leach solution is as follows:
4 Au + 8(NaCN) +O2 + 2 H2O = 4 NaAu(CN)2 + 4 NaOH
The second stage of the treatment via redox reaction is called the Merrill-Crowe process where zinc powder is added to cause a precipitation of gold and zinc.
2Au(CN) + Zn = 2Au + Zn(CN)4(-2)
This is further treated with sulphuric acid that dissolves the zinc and the remaining gold is then pure.
Last month it was 55 kgs, why the difference? Maximum output in march has been only 35 kgs of gold. With less manpower, we have given the recovery at the grade of 4 gms per 10. In the months of January and February it was only 1gm per 10, and Chitragunta where all the private lorries are going, they're giving less grade, only 1 gm per 10.
The transport charges are not enough, you're removing gold without transportation.
Interview with R. Anand about the extraction of gold via the heap leaching plant, manpower required for it and the possibility of gold from the KGF mines in the future.
There's no grinding, no electrical power, there's no machinery work also, only manpower, just conveyor system carrying the sand and removing the gold by standard leaching. So we're not using any electrical power, there's no crushing, jamming, grinding. In the ... mill also, ... makes the pellets
So power congestion less here..
The extraction of ore is negligible in this type of process.
J. Nair: So what is your assessment of the number of years the plant can go on?
Still we can give in writing, 75 years the gold will run, and after 75 years there is a growth of the immatured(?) gold, which is raw gold. after 75 years the raw gold is grown in the form of streaks. So growth is there, after 75 years the matured gold can be explored, so there is a growth like a plant, there is no stoppage of gold.
Only political infomration, politics stopping, there is no fund from Delhi, if they give about 200 crores which is lying in Reserve Bank of India we can explore more gold
J. Nair: Thank you, what's your full name?
My name is Anand.
J. Nair: A Anand, P Anand, Anandraman?
Anand MSc LLB, MSc in Chemistry
Take my picture also, put it in the TV also, I don't bloody care about anybody. 420 Union, they are not supporting the employees. At present one accident has been here, up to this time these people have not visited the person. His hand has gone. Such kind of union we are having.
That person is in Manipal right now, in the 6th floor, 601 bed number, you can go see him also. These fellows have not helped with money also, only they have put in hospital for treatment, for other facilities and all the peope are seeing.
Such kind of union we're having, such kind of management, what shall we do? At least these people encourage (wage raising?) or extra benefit also, we are also ready to go outside this company. We are getting a salary of only 3400 or 3500, such kind of salary is not enough for us. One of the lowest company in india this is I think, pay and all. Dangerous company and lowest payment company is BGML.
(Tamil): Tell them, the government has also not done anything, it is not taking care of anything.
In Bangalore also, nobody is seeing. On national TV you have to have us, then only all the people will see us, how the people are suffering here.
We are finishing our stage now.
He is our foreman here, like a supervisor. Ask any questions you want to ask him.
J. Nair: You are the secretary of the union?
Ya, this is the organising secretary, Mr. Shankar.
J. Nair: Oh, him.
Organising the Foreman's Association.
J. Nair: So are you planning to take VRS?
There's no point in taking VRS, I've finished only fifteen years of service, I'd be getting very less, compared to the officers, they'll be getting 8 to 10 lakhs, we'll be getting only 1.5 lakhs. So can't go in for VRS. If you're serviced, you have 30 or 35 years then it will be a benefit, we are too young to take VRS, we can serve still, we're hard working.
J. Nair: Are you looking for a job somewehere else?
Where else will i get a job? I'm not sure of getting a job anywhere else, that too a job like this, a government job, he's given us quarters, this that.
J. Nair: What is your job here?
I'm a foreman here, I'm in charge of this crusher.
J. Nair: And you are from KGF? Born here and brought up here?
Born in Ooty, settled in KGF
J. Nair: So what time is the smelting?
(Hinging?) moment we will ..., we'll take off this point, afterwards I'll take you inside.
J. Nair: Some people will be working here or not?
While putting ... we are charging manually, only in idle portion we are charging. You want that one also?
J. Nair: That's not going to happen is it?
They are standing, but not charging now. We can show the boiler running, you can take that picture.
(Tamil): Sir, take us also, our foreman, Foreman! He is not smiling, not doing anything.
We went on strike for 23 days, and nothing happened, they took revenge on the labourers, arrested them in the field itself ... (tape ends)