APC refers to a broad range of techniques and technologies that interact with process control systems. Advanced process controls are often deployed on top of the basic process controls that are built around PID control. It is a very cost-effective way to optimize your plant performance without changing the hardware. Nowadays APC is almost a commodity in refineries and large petrochemical complexes, like ethylene crackers and polymer plants.
More complex PID control structures like cascade, split range, override, Smith Predictors, decoupled schemes etc are often referred to as ARC (Advanced Regulatory Controls).
The chemical, fertilizer, power, and fine chemical industry have discovered the power of APC in the last 15 years. Also in these industries, APC is becoming very common.
Advanced Process Control benefits
There are many benefits APC can offer you. These are the most common benefits generated by APC systems on many different industrial processes:
- Reduced process variations beyond what is possible with traditional PID control.
- More hands-off operation. Under normal operating conditions, operators would not need to touch the process at all.
- Operate the plant always at the optimum. This can be at the maximum throughput, the lowest specific energy consumption, the point with the highest margins, or combinations of the above.
- APC respects under all conditions the process limits resulting in improved safety
APC and optimization
APC enables you to optimize your plant performance without changing the hardware. This makes APC solutions very cost effective.
Large process revamps can increase the production capacity by 10% to 40% at the cost of sometimes a hundred million dollars/euros. And the capacity increase is more in the range of 1% to 5% at the cost of a few hundred thousand dollars/euros.
Besides pure production increase or lower specific energy consumption APC also brings other benefits:
- More stable operations, meaning less variations.
- Less operator interventions
- Reduced alarms
- Less wear and tear on the equipment resulting in longer run lengths, less downtime
- better understanding of the process