What are the challenges of controlling using process analyzers?

Challenges include: long measurement delay (sample transport, analysis cycle - minutes to hours), calibration drift requiring frequent validation, maintenance-intensive (sample systems, reagents, electrodes), high cost (purchase and operation), reliability issues in harsh environments, and slow control response due to dead time. Mitigation: use inferential measurements (temperature, pressure correlations) for faster response with periodic analyzer feedback; cascade analyzer output to faster loop; apply Smith Predictor for dead time compensation; ensure robust sample conditioning; and use redundant analyzers for critical applications.