A Generalized Model on Prediction of Solid Flow Rate Though L-Valve

L-valve serves as an essential non-mechanical part to control solid flow rate in circulating fluidized bed (CFB). A number of correlations were suggested in last few decades by various authors to predict solid flow rate providing aeration rate or pressure drop across L-valve, and other parameters such as properties of particle or L-valve geometry, etc. The accuracy of these empirical correlations are questionable especially when operating condition is beyond the tested range. In this work, a simple model was proposed for gas and solid flow in L-valve section. By closing the model with literature data, a generalized dimensionless correlation was found to intrinsically account for the momentum transfer between the gas and solid flow. With the correlation as additional independent equation, the model is then able to predict solid flow rate providing other measurable parameters. The correlation was obtained as a single curve based on the data generated at various experimental configurations, such as particle properties and L-valve pipe size, etc. Thus, this model is considered as potentially generalized estimation for solid flow rate through L-valve, i.e. solid circulation rate in CFB, although it requests further data validation from other conditions, e.g. at elevated temperature and pressure.