Gas holdup in a shallow bubble column measured by electrical capacitance tomography (ECT)
Time-averaged gas holdup distributions were investigated in a 0.14 m i.d. shallow bubble column using ECT. In all the experiments deionised water was liquid phase and air was gas phase. The gas holdup profiles were measured at two axial locations at 4.75 and 17.75 cm above the distributor level. Hole gas velocity was varied from 4 to 186 m.s -1 . Single nozzle sparger was used as gas distributor. The free area of sparger plates (FA) and the hole diameter (d0) were varied in the range of 0.14 to 1.31% and 5.3 to 16 mm, respectively. It was found that the gas holdup increases with the increase of hole gas velocity.As the gas velocity increases beyond VN=38 m/s, a change of slope profile marks the regime transition from bubbling regime to jetting regime. Gas holdup and slope of the gas holdup profiles increase with the increase of hole diameter at the same hole gas velocity. A higher dominant frequency (2～3 Hz to 5～6 Hz) and a broad band are observed with the increases of hole diameter. In addition, the transition hole gas velocity is obtained and with the corresponding orifice Re as a relatively constant about 30000.
shallow bubble column gas holdup gas distributor FFT ECT
Qingbai Cai Chunyin Shen Gance Dai
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
国际会议
The 12th Asian Pacific Confederation of Chemical Engineering Congress(第十二届亚太化工联盟大会暨化工展览会)
大连
英文
2008-08-04（万方平台首次上网日期，不代表论文的发表时间）