Critical bed height for solid circulation in a compartmented gas-fluidizedbed

The influence of design and operating parameters on minimum upstream bed he ight required for steady solid circulation across a compartmented gas-fluid ized bed has been studied. The partition plate in the compartmented bed is fitted with two pairs of V-valve and riser with orifices in them. Silica sa nd of three different sizes, viz.,490 mum, 325 mum and 250 mum, has been us ed and the range of the aeration rate tested covers 1-3U(mf) through the be d, 5-60U(mf) through the V-valve and 0-60U(mf) through the riser. A model i ncorporating pressure balance across the circulation loop has been develope d to analyze the experimental findings. Studies show the existence of a uni que critical bed height for a given set of fluidization velocities through the bed, V-valve, riser and the size of the solids.