Multiscale Analysis to Determine the Sensitive Zones for Temperature Sensor Location in Tubular Reactors

• Published in: Chemical engineering & technology Vol. 44; no. 7; pp. 1259 - 1269
• Main Authors: Moguel‐Castañeda, Jazael G., Hernandez‐Ayala, Juan L., Gomez‐Rodriguez, Rafael, Bastidas‐Oyanedel, Juan‐Rodrigo, Hernandez‐Martinez, Eliseo
• Format: Journal Article
• Language: English
• Published: Frankfurt Wiley Subscription Services, Inc 01.07.2021
• Subjects: Cascade control; Disturbances; Evaluation; Fixed‐bed reactor; Maleic anhydride; Multiscale analysis; Nonlinear processes; Perturbation; Position sensing; Reactors; Sensitivity; Temperature sensors; Tubular reactor
• ISSN: 0930-7516; 1521-4125
• DOI: 10.1002/ceat.202000053

The sensitivity of benchmark tubular reactors subject to temperature and concentration of external perturbations was investigated. Two case studies were evaluated, a pseudo‐homogeneous axial dispersion dimensionless tubular reactor and a heterogeneous tubular reactor to produce maleic anhydride. For the dimensionless reactor model, the highest sensitivities in the reactor were located at the center and at the outlet for temperature and concentration disturbances, respectively, while for the heterogeneous reactor model the sensitivity does not undergo significant changes with feed disturbances. When variations in the most sensitive position occur, a cascade controller can be improved using multiple temperature sensors. The evaluation on weighting assignment of the temperature measurements for the cascade control scheme is also described. Temperature‐time series analysis is a technique easy to implement with low computational cost to calculate the Hurst exponent, which is applied for the identification of sensitive zones in tubular reactors and their displacement due to concentration and temperature perturbations. Sensitive zones can be useful for locating temperature sensors in the design of cascade control schemes with multiple measurements.