Mine tails dewatering - How to extract more water??
Mine tails dewatering - How to extract more water??
(OP)
Our tails contain 50% water and are very fine (90% < 150microns) We want to extract more water before placing on the tails dumps, for two reasons; to recover more water and to increase the density of our tails dumps. Recovering more water will relieve pressure on our water supply. Increasing the insitu density of our dumps will also increase the useful life of our tails dams. The density we acheive in our dumps currently is ~1.37t/m3
Any advice/experience would be appreciated
Any advice/experience would be appreciated





RE: Mine tails dewatering - How to extract more water??
You may want to read some excellent papers on why dams fail
http://www.tailings.info/dams.htm, http:/
or http://www.wise-uranium.org/mdas.html
If you have a long transport distance removing water before the dam may not be the best solution. You may want to instal dewatering wells around the dam, or look at explosive compaction of the dam so that you can expand its capacity. INCO in Sudbury did this in 2003, but if not in the area you may want to talk to any soils compaction expert who uses explosive compaction (There was a papet on this in CIM Bulletin Dec 2003)
broadpeng@rogers.com
RE: Mine tails dewatering - How to extract more water??
Regards,
RE: Mine tails dewatering - How to extract more water??
As you mention it we have an expert coming to see us tomorrow!
The issue of pumps is another issue we are working through. Can we set up pumps in series, about 1.5km apart without having cavitation problems? I know that we can use small tanks and re-mixers to maintain positive head on all the pump inlets, yet a cheaper option would be to have them all on one line and use some type of controllers & VF drives to maintain positive inlet head at each pump. Can you think of a company that specializes in this type of installation?
RE: Mine tails dewatering - How to extract more water??
depends on which continent your project is on.
RE: Mine tails dewatering - How to extract more water??
What information do you have?
RE: Mine tails dewatering - How to extract more water??
Good luck
RE: Mine tails dewatering - How to extract more water??
We were not as fine, had a 65 mesh grind, but our overall tails density was very close to yours when we switched from sub-aqueous to sub-aerial deposition. Nothing fancy on the tails pumping side, just diligent deposition cycling and water management on the tails.
The water reclaim benefits occured rapidly. The design intent was to switch from a clearwater pond against an earthen dam to a 'solid' beach against the dam, and ultimately permitting upstream construction. It took about eighteen months, but worked nicely. There were two benfits expected and realized: 1) construction costs went from engineered earthfill to coarse rockfill. 2)Tails densification worked well, allowing 2.5 times the original amount of material within the originally permitted footprint.
This was at 7,000 ft elevation in the state of Utah. Given your additional many months of sun, shouldn't have too much difficulty in Australia. Incidentally, the original literature (and consultant) guidance on our effort came from South Africa, though through their Denver office. The only discrepancy we had with them was we said we could build upstream, which we did. Its now completed and successfully reclaimed. Deer, bunnies, whole nine yards. Squirrels like the rocks.
Food for thought, if your material will release its moisture under sunlight. We diminished our overall water requirements even though we were increasing the effective evaporation across the tails beach. If you need the water in your plant, you may have to go the paste route as the threads above indicate. Higher pumping costs, but with your grind the wear shouldn't be too bad.
Good luck. Give me a holler if you need more detail.
RE: Mine tails dewatering - How to extract more water??