高长径比三相内环流反应器中细颗粒相含率和循环液速的分布研究

在高径比为22的三相内环流反应器中,在常温常压下以空气-水-石英砂为物系,研究了在不同粒径下上升区固含率、下降区固含率和上升区循环液速随表观气速的变化规律和不同粒径下轴向固含率的分布情况,以及在固体体积分数不同的条件下,平均气含率和上升区气含率随表观气速的变化情况。结果表明:当粒径(ds)≤0.3 mm时,上升区固含率随表观气速的增加呈平缓变化趋势,下降区固含率随表观气速的增加而增加;当0.3 mm

Distribution study on phase holdup and liquid circulation velocity of fine particles in three-phase internal-loop airlift reactor with big ratio of height to diameter

In three-phase internal-loop airlift reactor with the ratio of height to inner diameter of 22, under nornlal temperature and at- mosphere with air-water-quartz sands particles as matter system, the change hale of solid holdup in riser and downcomer, and the liquid cir- culation velocity in riser following with superficial gas velocity are studied, and the distribution status of axial direction solid holdup of differ- ent grain diameter is researched. The variation status of average gas holdup and gas holdup in riser following with superficial gas velocity at different solid volume fraction is investigated. The results show that the solid holdup in riser changes gently with the increase of the superficial gas velocity, the solid holdup in downcomer increases with the increase of gas superficial velocity when grain diameter ds ≤0.3 mm. The solid holdup increases ＇after the first drop with the increase of the superficial gas velocity and the solid holdup in downcomer decreases with the in- crease of gas superficial velocity when 0.3 mm 〈 ds ≤ 1.2 rnm. The solid holdup in riser decreases with the increase of the axial direction height, the liquid circulation velocity increases with the increase of the superficial gas velocity at different grain diameter. The average gas holdup and gas holdup in riser increase with the increase of gas superficial velocity at different solid volume fraction.