Real Time Implementation of Standpipe Model for Solids Flow in Circulating Fluidized Bed

Increased accuracy of solids flow meters can be achieved with sensor fusion; the combination of solids velocity measurement with other process sensors to define the process state of the solids while they flow. In a circulating fluidized bed aeration flow, temperature measurements, and pressure differentials are routinely measured to ensure stable process operations. These process measurements were used as input to real-time model of the standpipe where the velocity measurement was taken to determine the actual solids bed density. The model development and implementation are described with the objective of updating the measured flows continuously in real time. Real time optimization techniques use the pressure measurements for inferring voidage and apply the inferred values to estimate the pressure profile and aeration split. In essence, the approach becomes solving nonlinear least squares problem and closure of mass balance of gas in real time.