油菜秸秆颗粒在导向喷动流化床中的流动特性

Flow characteristics of oilseed rape straw in spout-fluidizing bed with a draft tube

在内径150mm、高1040mm、90°V形气体分布板的有机玻璃制导向喷动流化床实验装置上，采用密度为2670kg／m^3,粒径分别为0．83～0．55、0．55～0．38和0．38～0．25mm窄筛分粒径石英砂，以及密度为738kg／m^3、粒径为0．85～0．42mm的油菜秸秆颗粒为原料，对秸秆颗粒-石英砂混合与流动效果、床层压降、中心喷泉高度、固体循环速率等流动特性进行了测定并建立了操作相图。研究表明，总重量为500g，比例为4：1的0．38～0．25mm石英砂和秸秆颗粒混合物在导向喷动流化床内混合与流动效果较好，能实现很好的喷动流化；固体循环速率和中心喷泉高度随操作气速的增加而增加；同时建立了本试验条件下的操作相图。

Experiments were performed in a 150mm inside diameter, 1 040mm height polymethyl methacrylate column with 90° conical distributor for the study of mixing effect,pressure drop, central fountain height,solid circulation and flow regime map of spout-fluidizing bed with a draft tube. Two kinds of bed material were used. The diameter of quart sand was 0. 83-0. 55,0.55-0. 38 and 0. 38-0.25ram with a density of 2 450kg/m^3. The diameter of oilseed rape straw was 0. 85-0. 42mrn with a density of 738kg/m^3. It was found that fluidization could be well realized in draft tube spout-fluidizing bed when the ratio of quart sand of 0.38-0. 25mm diameter and oilseed rape straw was 4 ： 1 with a total weight of 500g. Solid circulation velocity and central fountain height increased when operating gas velocity was increased. Flow regime map was set up based on the conditions of this experiment.