Plant Optimization & Metallurgical Recovery Audit
Optimization begins with empirical data: on-site slurry sampling, particle size distribution (PSD) analysis, cyanide consumption curves, carbon loading assays, and tailings diagnostic analysis.
Our metallurgical engineers audit each circuit stage to pinpoint exact recovery leaks — whether in gravity recovery, leaching kinetics, carbon activity, or electrowinning cell current efficiency.
We deliver a prioritized, cost-benefit ranked engineering recommendation report and provide hands-on implementation support to ensure sustained performance gains.
- Typical Recovery Boost
- +5% to +18% (Verified on Field Audits)
- Reagent Cost Reduction
- 15% – 30% (Cyanide & Lime Consumption)
- Diagnostic Timeframe
- 5 – 10 Days (On-Site Sampling & Assay)
- Deliverable
- Actionable Audit Dossier (Ranked Engineering Roadmap)
Visual Assets & Field Records — Plant Optimization & Metallurgical Recovery Audit
Inspect high-resolution mechanical assemblies, 3D CAD flowsheets, on-site construction rigging, and diagnostic testing apparatus. Click any record to zoom up to 2.5x with full pixel clarity.
Leach Kinetics & Carbon Testing
Diagnostic laboratory testing measuring cyanide dissolution rates, lime consumption, and activated carbon loading capacity over time.
Gravity Separation Circuit Audit
On-site examination of centrifugal concentrators and shaking tables to maximize coarse free-gold recovery ahead of cyanide leaching.
Precision Assay & Bullion Weighing
High-precision weighing (4.207 kg gold bullion batch) and certified assay verification to document recovery yields and custody provenance.
Centrifugal Concentrator Tuning
Fluidization water pressure and cycle-time optimization on centrifugal concentrators to boost single-pass recovery rates.
Technical Scope & Certified Deliverables
Diagnostic Testing Scope
- Grind Size Distribution (PSD / P80)ASTM E11
Determines whether gold is under-liberated (too coarse) or over-ground into slime.
- Diagnostic Cyanidation Leach TestsMetallurgical Standard
Identifies refractory gold locked in sulfides, carbonaceous matter, or silicate matrix.
- Carbon Activity & Fouling ProfileASTM D3838
Measures carbon adsorption rate (R-value) and organic/calcium carbonate fouling levels.
Engineering Recommendations
- Circuit Bottleneck Identification ReportGreen Ngoria System 4
Pinpoints specific equipment and process stages constraining plant throughput or recovery.
- Reagent Optimization ScheduleCyanide Code Aligned
Calculated stoichiometric dosing rates for NaCN, hydrated lime, lead nitrate, and flocculants.
- Prioritized Capital / Operational RoadmapCost-Benefit Matrix
Clear list of quick-win operational tweaks vs high-ROI equipment upgrades.
Core Competency Register
- Comprehensive plant mass balance and metallurgical circuit sampling
- Grinding circuit profiling (P80 particle size distribution and recirculating loads)
- Hydrocyclone classification cut-point (D50) and apex/vortex finder optimization
- Cyanide leaching kinetics, dissolved oxygen profiling and lime buffer tuning
- Activated carbon activity testing, attrition rate audit and regeneration review
- Elution column temperature, pressure, and electrowinning cell current efficiency audit
- Tailings assaying (solid vs solution gold loss breakdown and diagnostic leach)
- Reagent dosing automation and operational Standard Operating Procedure (SOP) updates
Phase-by-Phase Execution Pathway
Baseline Assessment & Data Intake
Review historical production records, head grades, reagent logs, and plant flowsheets.
- Baseline Data Audit Log
- Sampling Point Map
- Diagnostic Test Plan
On-Site Slurry Sampling & Field Measurements
Conduct synchronized sampling across all circuit stages over full operating shifts.
- Shift Slurry Sample Log
- Slurry Density Measurements
- DO & pH Profile Sheets
Laboratory Assays & Kinetics Modeling
Perform size fraction assays, diagnostic leaching, and carbon adsorption kinetic tests.
- Metallurgical Assay Sheets
- Leach Kinetic Curves
- Tailings Loss Breakdown
Engineering Report & Implementation Support
Deliver prioritized recommendations and assist plant operators in tuning circuit parameters.
- Plant Optimization Master Report
- Updated Operator SOPs
- Verification Assay Log
Design Criteria & Technical Parameters
| Engineering Parameter | Standard Design Criteria | Application & Notes |
|---|---|---|
| Dissolved Oxygen (DO) in Leach Tanks | 6.0 – 8.5 ppm continuous | Maintained via spargers or compressed air injection |
| Slurry pH Buffer Level | 10.2 – 10.8 with Hydrated Lime | Prevents toxic HCN gas formation and optimizes cyanide efficiency |
| Carbon Concentration in CIL Tanks | 10 – 20 g/L slurry volume | Staged counter-current movement to minimize solution losses |
| Electrowinning Single-Pass Gold Deposition | > 90% solution gold stripped | Optimized voltage, flow rate, and cathode surface area |
Frequently Answered Engineering Questions
How quickly can Green Ngoria perform an on-site plant optimization audit?
Our metallurgical audit team can mobilize within 3 to 7 business days. On-site sampling typically requires 3 to 5 days, followed by laboratory assays and delivery of the final optimization report within 10 to 14 days.
Can optimization reduce our cyanide and reagent expenditure?
Yes. Most processing plants over-dose cyanide and lime due to lack of real-time kinetic control. Optimization typically cuts reagent costs by 15% to 30% while maintaining or increasing recovery.
Does the audit include recommendations for re-processing old tailings?
Yes. We conduct diagnostic tailings assays to determine recoverable gold in existing tailings dams and engineer economic regrind or CIL re-treatment flowsheets.
Tell us what you need built, processed or supplied
Send the scope, quantities and delivery location and the enquiry reaches the right division. For an installed circuit, a technical plant assessment is the faster route.
Customer care & enquiries
Director lines & emails: Leadership Profiles →
Tatu City, Kijani Ridge, Nairobi, Kenya