Research of Particle Diameter Influences on Flow Characteristics Based on Feedback Valve of Internal Circulating Fluidized Bed

Background: Loop Seal is a key component in circulating fluidized bed. It is necessary to study its internal flow rules. Diameter of solid particle in Loop Seal is too large or small can produce bigger effects for fluidized bed operation. Objective: We will study internal flow rules in Loop Seal, and look for relationship between the key parameters of solid particle circulation and particle diameter by cold experiment. Method: The cold experiment method is introduced based on a new J-type Loop Seal of three chambers internal circulating fluidized bed for different particle diameters silica sand in the paper. It includes building the experimental device and measuring related parameters. The equivalent model and theory formula of solid particles circulation are provided. The influences of particle diameter on three key parameters of the solid particles circulation are discussed on emphasis. Results: The experiment results show that on the same conditions the height difference of two chambers in running increases as the particle diameter increasing. The dynamic head of feedback valve in running is not affected by the right lateral blow nearly, but is linear relationship with the left lateral blow, relationship between their slope coefficients and intercepts and relative value of particle diameter both are linear nearly; the resistance coefficient in the feedback valve is power exponent relationship with right lateral blow, and particle diameters have almost nothing to do with it. Conclusion: The method provides references for particle diameter selection and usage, design and operation for feedback valve of internal circulating fluidized bed. Here, we also discussed few related patents.