Methods for mine tailing clean-up using recovery technologies
OwnerGordon Kingsley, Richard E. Petersoninventors
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Abstract
A method for site remediation for mitigating contamination from metals or metal compounds, particularly resulting from the situation of mine tailing waste on or near water sources, including the reprocessing and redeposit of separated sands and slimes in-site in a manner to encourage rather than inhibit leaching of residuals by chelating agents or biological agents with recovery of leachate and removal of metals or metal compounds.
Claims23
A method for remediation of sites on which are deposited mine tailings having metals and metal compounds with a substantial proportion of the tailing comprising complex sulfide tailings comprising the steps:
- (a) separating sands and slimes from larger materials;
- (b) separating sands from slimes;
- (c) depositing slimes at a site location suitable for immersing slimes in water with means for drawing water from the top surface of the slimes;
- (d) depositing sands at a site location with means for extracting percolated water from under the sands;
- (e) spraying the surface of the sands with a water solution having a leaching agent wherein the sands have metals and metal compounds that are contacted by the water solution having the leaching agent;
- (f) injecting the slimes with a water solution having a leaching agent, wherein the slimes have metals and metal compounds that are contacted by the water solution having leaching agent;
- (g) draining water with leached metal compounds from under the sands;
- (h) drawing water with leached metal compounds from the top surface of the slimes;
- and
- (i) recovering metal compounds from the water drawn from the sand and slimes.
A method of in situ remediation of sites having zones contaminated with metals and metal compounds having a composition including metal oxides and metal sulfides comprising the steps of:
- (a) installing hydrogeologically engineered extraction wells, under zones contaminated with metals and metal compounds;
- (b) sprinkling the site with water containing a benign chelating agent wherein the water and chelating agent percolate through the zones;
- (c) contacting the metal oxides and metal sulfides in the zones with water containing the chelating agent;
- (d) extracting water from the extraction wells;
- (e) recovering metal salt compounds from the water containing the chelating agent;
- and
- (f) recycling the water containing the chelating agent to the sprinkling step.
The method of remediating a site having complex sulfide tailings with recoverable mineral and metal values comprising:
- (a) classifying tailings according to multiple size fractions.
- (b) specific gravity separation of select size fractions to recover a concentrates of heavier material including a predominance of metals and compounds and a discharge of lighter material including remaining metals and metal compounds in predominately silicas and calcites;
- (c) separating calcites from the discharge of lighter material for storage;
- (d) selectively depositing the lighter material on site in a manner that enhances leachability;
- (e) circulating water having leaching agent through the deposited lighter material;
- and
- (f) extracting mineral and metal values form the circulation water;
- and
- (g) using separated calcites for neutralization of circulation water.
Dependencies are inferred from the claim text.