关键词: 变径组合提升管, 团聚物, 持续时间, 循环流化床

Abstract: Cluster existence time in an combined diameter adjustable riser of circulating fluidized bed was measured and analyzed within the Gs/（ρg.Ug） range of 2.13 — 47.95. It was found that the existence time of single cluster was 0.001 28 — 0.601 60 s. However，mean existence time of local cluster was 0.014 32 — 0.160 64s. The clusters with existence time higher than 0.064 00 s accounted for 12.31%，while clusters with existence time lower than 0.064 00 s was 87.69%. When the solid/gas ratio was relatively low, the average duration was dominated by low concentration aggregates. When the solid/gas ratio was high, the residence time of cluster in area close to the reactor wall was dominated by high concentration of aggregates. By multi-scale analysis of time，in low concentration cluster，the quantity of the clusters within the duration range of 0.001 28 — 0.038 40 s was primary, and in terms of the influence on the average duration, the aggregate with a duration of 0.012 80 — 0.038 40 s was the most important. While on the amount and the influence on the average duration, the aggregate with a duration of 0.064 00 — 0.128 00 s was in the first position.

Key words: combined diameter-changing riser, cluster, existence time, circulating fluidized bed