Coarse Particle Flotation of Coarse Gold and Gold-bearing Ore by Fluidized-bed-flotation

The froth flotation process has been the most widely used mineral concentration technique for more than a century. However, neither flotation columns nor conventional flotation cells are efficient in processing coarse mineral-bearing particles. Most sulfide mineral particles, above a particle size of 150 microns, are commonly lost to flotation tailings on a regular basis. HydroFloat (HF) is a novel fluidized-bed flotation technology developed by Eriez to address the above issue. To evaluate the suitability of the HF technology, a six-inch diameter unit was used to carry out test work at a gold mine site in Nevada. The test HF unit was installed in the flotation plant and was tested in a semi-continuous mode by using the +150-micron (100 mesh) size fraction of the plant flotation tailings as its feed. The initial study found that more than 50 % of gold from the tails resided in the above 150-micron size range which constitutes 40% tails mass. This finding led to a strong motive towards testing HF at the mine site.The main goal of the proposed study was to evaluate the suitability of fluidized-bed flotation for coarse gold and gold-bearing minerals. This in-plant test program utilized a statistical response surface methodology to optimize the recovery of coarse gold and gold-bearing particles as a function of several key process variables including conditioning time, collector dosages, aeration rate, elutriation water rate, feed rate and feed solid content. Initially, collector dosages and conditioning times were optimized by varying one factor at a time. After a detailed optimization program, it was found that a concentrate grade of 1.154 gAu/tonne with 44.20 % recovery can be obtained with the optimized values of 0.5 kg/min feed rate and teeter water rate of 2 L/min. The ideal range for a solid percentage was 51-60 % and the aeration rate should be in the range of 0.20 - 0.45 L/min. Performance optimization and regression model construction of the test work was achieved using statistical analysis software: Design Expert.

Level thesis:degree_level

Master's Degree

Year dc:date.issued

2021

Author dc:creator

• Patel, Himeshkumar Ashokbhai

Advisor dc:contributor.advisor

• Casey, Sean

Committee members dc:contributor.committeemember

• Sattarvand, Javad
• Frost , Brian

• Coarse particle flotation
• Fluidized bed flotation
• Gold flotation
• HydroFloat
• Precious metals

Handle dc:identifier.uri

http://hdl.handle.net/11714/8093

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/8093