7 questions to find hidden losses in your mineral processing plant
Is your mineral processing plant as stable as it should be?
Hidden control loop instability can quietly erode performance: lowering throughput, reducing recovery, and increasing operator interventions. When PID loops aren’t tuned correctly, your plant spends less time reacting. Your operators make big changes too late, creating downstream surges and efficiency losses and your shift-to-shift results become dominated by operator preference, experience and vigilance
The good news? You don’t need a full digital overhaul to fix this. The fastest gains often come from getting the basics right: tuning loops properly and restoring confidence in automation.
This Plant Stability Health Check helps you uncover where instability is hiding. Answer seven targeted questions to identify early signs of control-related losses and learn practical next steps to stabilise your operation.
If you score “yes” on three or more, it’s time to review your control strategy – because small changes can unlock big improvements in throughput and recovery.
1. Are critical control loops often run in manual mode?
Some loops have to be operated manually, because Auto mode doesn’t exist or no longer works. The issue with this is that each operator adjusts differently, leading to inconsistent performance and increased wear.
Why it matters:
Manual operation is a symptom of inefficient process control from process changes, instrument and maintenance issues or upstream processes It also introduces operator variability, reducing consistency and increasing equipment wear.
Quick win tip:
Audit loops running in manual and retune PID parameters to restore automation confidence.
2. Do shift results vary significantly between crews or times of day?
Are loops operating outside of process parameter setpoints. Is the feed to a circuit erratic and unpredictable?
Why it matters:
Large performance swings often trace back to inconsistent control strategies or unstable loops.
Quick win tip:
Compare trend data across shifts to identify loops that behave differently under varying operator inputs.
3. Are alarms and operator interventions a daily norm?
Frequently putting loops into manual means your control system is reactive, not proactive. Operator fatigue increases, and late, large changes cause swings in operations. Frequent smaller automated changes provide smoother operation.
Why it matters:
Frequent overrides mean your control system is reactive, not proactive, leading to operator fatigue and missed critical events.
Quick win tip:
Reduce alarm frequency by stabilising loops and reviewing alarm rationalisation.
4. Is recovery or throughput not predictable from process parameters?
Poorly tuned loops quietly reduce efficiency. Changes to the processing conditions over time lead to changes in tuning requirements and often mimic feed variability, masking the true cause.
Why it matters:
Loops with outdated tuning parameters mimic feed variability, masking the real cause of production dips.
Quick win tip:
Analyse trend data for subtle mismatches between control response and process conditions.
5. Do operators use different ‘rules of thumb’ for the same circuit?
If every shift runs differently, plant automation isn’t working as well as it could. Benchmarking the plant to justify improvements may also become difficult.
Why it matters:
Inconsistent or outdated control strategies causes low trust in automation and increases friction between shifts.
Quick win tip:
Document best practices and retune loops to reduce reliance on manual adjustments.
6. Are your engineers and operators spending more time reacting than improving?
If every shift runs differently, plant automation isn’t working as well as it could. Benchmarking the plant to justify improvements may also become difficult.
Why it matters:
Instability keeps engineers in firefighting mode. Time spent explaining yesterday’s problems is time lost improving today’s performance.
Quick win tip:
Prioritise stabilisation projects to free up engineering bandwidth for continuous improvement.
7. Do you lack in-house expertise to diagnose control issues?
Even strong teams may lack the time, attention or input on control or instrumentation strategies to solve underlying issues.
Why it matters:
Strong teams can still miss underlying control problems without specialised knowledge.
Quick win tip:
Consider a targeted loop tuning audit for critical loops to uncover hidden losses and restore stability quickly.
Results & reflection
If you answered “yes” to three or more question your plant might be operating below its potential. Control loop instability is a hidden loss that compounds daily.
The good news is that these issues are fast and low-cost to fix. A closer look at your control setup can:
- Restore automation confidence by retuning PID loops and reducing manual mode dependence
- Stabilise critical circuits to improve throughput and recovery without major capital investment
- Reduce operator interventions and alarm fatigue, freeing your team to focus on optimisation
- Unlock hidden capacity by eliminating variability and standardising control strategies
Time to fix the cause, not just the symptoms.
Stability is the foundation of optimisation and often the cheapest step.
Step 1: Take the Plant Stability Self-Assessment
If you haven’t already, download our free checklist and quickly identify signs of instability in your grinding, flotation, tailings, or other circuits.
Step 2: If your plant shows signs of instability, get in touch
Get in touch, and we’ll arrange a call with one of our Loop Tuning experts from Mipac’s Process Optimisation team.
Together, we’ll review your results and outline the fastest way to restore stability and unlock hidden performance.
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