Optimization goals for the finish grinding circuit will usually include:
Consistent, well-defined product quality
Reduced energy consumption
Minimal waste
Maximum throughput
Traditionally the finishing circuit is controlled manually with reference to off-line Blaine analysis but this approach has a number of drawbacks. Periodic analysis, sampling and measurement errors, and the time delay associated with off-line measurement restrict the development of secure process knowledge. Consequently operational confidence may be quite low and plant control relatively coarse – large changes made at relatively infrequent intervals. This leads to variable product quality. The operating point for the process may be set some way from the true constraints imposed by meeting the specification, resulting in over-grinding.
Manual control with intermittent analysis
Frequent and reproducible analysis allows operators to more easily observe the impact of a process change; continuous, real-time measurement being the optimal solution. With on-line analysis in place the links between cause and effect become obvious and quantifiable, leading to better control. Confidence increases and the plant is pushed harder, towards the real operating boundaries. Implementing automated control consistently maintains the plant at an optimal operating point with negligible manual input, producing gains in the form of better product quality, increased throughput and reduced waste (energy, material, low value manual input).
Tackle product variability
Tighten control and consistently maintain the fineness of the finished cement at a precisely defined set-point.
Increase throughput
De-bottleneck the plant by removing the inefficiencies associated with sub-optimal control including over-grinding and long product changeover times.
Eliminate over-grinding
Mill sufficiently to just meet the specification but no further to minimize specific energy consumption.
Reduce changeover times
Instantly observe the impact of process actions to move swiftly and accurately between set-points.