Abstract:
The project addressed the critical inefficiencies in existing sluice box designs used by artisanal
gold miners in the Tiira gold mines, Uganda. These inefficiencies included difficulties in feed and
water delivery, suboptimal inclination angles and the use of materials that contributed to high
mercury contamination, posing significant threats to both environmental health and miner wellbeing.
To
overcome
these,
the
project
aimed
to
redesign
and
fabricate
a
portable
and
efficient
sluice
box
for
artisanal gold miners in Tiira, Uganda, addressing inefficiencies in existing designs such
as poor feed delivery, suboptimal inclination angles, and high mercury contamination.
The research focused on four specific objectives which included determination of optimal sluicing
parameters for improved recovery efficiency, development of a portable and efficient sluice box
design, fabricating and testing the new design to evaluate its performance then lastly performing
financial analysis to which determined the economic viability of the project.
Through field surveys and laboratory analysis of ore samples, key sluicing parameters including
slope angle, water flow rate, and feed rate were optimized using Response Surface Methodology
(RSM) and Central Composite Design (CCD). The redesigned sluice box achieved a 20.1%
increase in gold recovery (from 67.75% to 87.8%) by implementing an optimal slope angle
of 13.5°, a sluice length of 1.3 m, and a width of 0.6 m. Sensitivity analysis revealed that slope
angle contributed 40.65% to recovery efficiency, followed by velocity (22.76%) and flow rate
(20.33%). Constructed from mild steel for durability and portability, the final prototype
weighed 12.88 kg and featured foldable components for ease of transport. Financial analysis
confirmed viability, with a 2.8-year payback period and a profitability index of 2.944. The project
demonstrates that optimized sluice box designs can significantly enhance gold recovery while
reducing environmental and health risks associated with mercury use in artisanal mining.
Future work should focus on material/riffle optimization for better performance and cost.
Essential training for miners on optimal techniques and sustainable methods is crucial.
Subsequent efforts must address scaling up the design for mass production and wider adoption.
