ABB Ability™ Expert Optimizer for mining

Challenge

• Material grinding (and crushing) is one of the most important steps in extracting minerals from ores. Grinding consumes ~50% of plant energy. Maintaining mill load and power balance is the foundation for all downstream improvements. Optimal design of grinding circuits for both consistent product quality and energy efficiency is crucial for the minerals plant’s performance. Control of grinding circuits is difficult due to significant time delays and time lags in the process and due to variable material properties of the incoming ore. 

Expert Optimizer goals

•  Consistently strike the balance between required throughput, stable grinding and energy use.

How it works

•  APC identifies optimal operational parameters depending on the material fed to the mill - against process constraints such as grind size, cascade angles, mill load, density and power draw. 

Benefits

• 1-3% increase in throughput
• 10% reduction in energy consumption
• 50% reduction in quality variability
• Better performance of downstream processes due to better control of the grinding process
• Increased mill liner lifetime

Challenge

• Flotation is a key process in many mineral plants to separate the product mineral from the gangue. The key requirement of the system is to achieve optimum product quality with minimum reagent consumption. Control is difficult due to variable chemistry and size distribution of the material fed to the process. Flotation is highly non-linear and delayed – manual tuning can’t keep up. APC maintains stable froth conditions and reagent dosing.

Expert Optimizer goals

• Minimize reagent overdosing whilst maximizing valuable metals recovery

How it works

• APC stabilizes the froth depth and reduces variability of flotation cell levels - for more predictable and consistent concentrate quality.

• Sets up for next-gen vision-based control when integrated with flotation cameras. 

Benefits

• 1-3% increase in recovery
• 30% reduction in reagent consumption
• 20-30% reduction in variability

Challenge

• Thickeners are critical for water recovery but notoriously unstable – this is the most variable circuit in the plant. APC ensures consistent solids underflow and optimized flocculant use.

Expert Optimizer goals

• Minimize flocculant additives whilst stabilizing bed mass, underflow density, rake torque

How it works

• APC, with its moving horizon estimation, exploits the long delays and interactions to predict and drive the thickener toward the optimum achievable constraints.

• Benefits

• Increase clean water recovery
• Reduce density variability
• Reduce additive consumption

Challenge

• Pyro furnaces / kilns / calciners are used in many minerals processing plants either as an intermediate process or as a final step to produce a finished product. The process is characterized by high fuel consumption. Control is difficult due to internal cycles in the furnace and the uncertain raw material properties.

• Thermal and chemical reactions in pelletizing furnaces produce off-gases containing SO2 and dust. Gas cleaning systems using lime slurry and temperature control are critical to ensure environmental compliance. Process delays make real-time SO2 emissions control difficult. Operators run with wide safety margins leading to overuse of lime slurry. 

Expert Optimizer goals:

• Achieve consistent control of the temperature profile
• Optimize the temperature profile to minimize fuel consumption
• Reduce product variability
  
• Enforce SO2 emission limits at lower reagent costs

Benefits

• Increased output by reduction of process disturbances

• Reduced fuel consumption

• Decreased SO2 emissions & deviations from target

• Reduced lime consumption

• Improved stability of water exhaust