Fluidized bed agglomeration is an important and challenging problem for thermal cracking in fluid cokers. A low coker temperature can be problematic because the bitumen is injected into the fluidized bed with a different viscosity, resulting in formation of agglomerates of varying sizes, which slows the cracking reactions. In the present study, the bed material agglomeration process during nozzle injection of multiviscosity liquid was investigated in a fluidized bed operated at different mass ratios of the atomization gas to the liquid jets (GLR = 1%–3.5%) and gas velocities (3.9U_mf and 5.9U_mf) based on a conductance method using a water–sand system to simulate the hot bitumen–coke system at room temperature. During the tests of liquid-jet dispersion throughout the bed, different agglomeration stages are observed at both gas velocities. The critical amount of tert-butanol in the liquid jets that could lead to severe agglomeration of the bed materials (poor fluidization) at GLR = 1% is about 10 wt% at the low fluidizing gas velocity (3.9U_mf) and 18 wt% at the high gas velocity (5.9U_mf). This study provides a new approach for on-line monitoring of bed agglomeration during liquid injection to guarantee perfect contact between the atomized liquid and the bed particles.

对于流化焦化器的热裂化而言，流化床附聚是一个重要且具有挑战性的问题。较低的焦化温度可能是有问题的，因为将沥青以不同的粘度注入流化床中，导致形成大小不同的附聚物，从而减慢了裂化反应的速度。在本研究中，在流化床中研究了多粘度液体的喷嘴注入过程中床层材料的团聚过程，该床在不同质量比的雾化气体与液体射流（GLR = 1％–3.5％）和气体速度（3.9 U）下运行_mf和5.9 U _mf）基于使用水沙系统的电导方法来模拟室温下的热沥青-焦炭系统。在整个床内的液体喷射分散测试期间，在两种气体速度下都观察到不同的附聚阶段。在低流化气体速度（3.9 U _mf）和18 wt％的情况下，在GLR = 1％时，可能导致床层材料严重团聚（流化不良）的液体喷嘴中的叔丁醇的临界量约为10 wt％。在高气体速度（5.9 U _mf）下。这项研究提供了一种在线监测注液过程中床凝聚的新方法，以确保雾化的液体与床颗粒之间的完美接触。