循环流化床(CFB)作为一种新兴反应器,其结构简单、气固接触效率高、处理量大,成为气固二相干燥应用研究的新方向.文中在自建的循环流化床(内径0.104 m×高2.35 m)内,以玉米淀粉(dp=8 μm,ρp=800 kg/m3)为C类颗粒,进行了连续干燥.实验初步研究了进料速率、进风温度及气速等操作参数对淀粉平均停留时间及出口含水质量分数的影响,并与快速流化床干燥结果进行比较.研究表明:相同实验条件下淀粉在循环流化床中停留时间比快速流化床更长,出口含水质量分数比快速流化床更低；淀粉的平均停留时间随气速及进风温度的增加而降低,进料速率对平均停留时间影响不大；淀粉出口含水质量分数随进料速率的增加而增加,随气速及进风温度的增加而降低.%As a new generation of reactor, circulating fluidized bed (CFB) is becoming a new trend of the research of gas-solid two-phase flow drying technology for its simple structure, large capacity and high efficiency of gas-solid contact. The continuous drying of group C particles was carried out in a CFB (0.104 m ID×2.35 m high) dryer. Corn starches ( dp = 8 μm ,ρp = 800 kg/m3) as group C particles were used. The average residence time of corn starches and its final moisture mass fraction were determined for varying value of the parameters including the feed rate, inlet air temperature and gas velocity. The results were compared with that of the fast fluidized bed dryer. It shows that starches stay longer and have lower outlet moisture mass fraction in the CFB dryer than that in fast fluidized bed dryer under the same conditions; the average residence time of corn starches decreases with increasing inlet gas velocity and air temperature, but is slightly affected by the feed rate; the final moisture mass fraction of corn starches increases with increasing feed rate and decreases with increasing inlet gas velocity and air temperature.
展开▼
