An investigation of the aeration proportion effect at the supply and recycle chambers on the optimal operation point of the U-type loop seal and the maximum solid circulation rate in a fluidized bed reactor

Abstract

A loop seal is used to control a solid circulation rate and loop seal aeration ratios at the supply and recycle chambers are another factor that affects its efficiency and circulating behaviors of solid particles in a fluidized bed reactor. This research aimed to find the proper aeration proportion and operation point of the loop seal that affected the highest solid circulation rate. A riser used in the experiment had a cross-sectional area of 100 × 100 mm2 and 4500 mm height above a distributor plate. A U-type loop seal was constructed by a supply chamber and a recycle chamber with the same cross-sectional area. A horizontal passage of 50 mm length was connected with both chambers. The sand was a bed particle with an average diameter of 320 μm. The loop seal aerations were fed at the bottom of the supply and recycle chambers. It was found that the loop seal could not operate with supply-aeration flow rate percentages (PQS) of 0% and 100%. The PQS of about 73% gave the maximum solid circulation rate and was an optimal operation point at which air supplied at the supply chamber started bypassing into the recycle chamber.