Department of Bioscience, The Nishi-Tokyo University, Uenohara, Yamanashi 409-01, Japan.
Biotechnol Bioeng. 1992 Jul;40(3):346-52. doi: 10.1002/bit.260400303.
A new type of bubble aeration column called a hollow fiber membrane (HFM) aeration column was proposed, which was featured in the use of hollow fiber membranes and gave a high bubble density in the column. The value of k(L)a was increased by modifying the membrane surface for making the pore size smaller. The Sauter mean diameter of bubbles (D(vs)) was 2.0 +/- 0.1 mm in the range of the superficial gas velocity from 0.02 m s(-1) to 0.065 m s(-1), while that obtained for the bubbles near the membrane was 811 mum at the superficial gas velocity of 4.0 x 10(-4) m s(-1). The difference was ascribed to the effect of coalescence of bubbles. The value of K(L)a increased in proportion to the superficial gas velocity up to 0.02 m s(-1), and was almost constant above 0.03 m s(-1). The maximum value of k(L)a, 2.5 s(-1), was higher than those of the other aeration columns reported previously. The pneumatic power consumption per unit liquid volume (P(v)) for obtaining the same k(L)a was the smallest in the HFM aeration columns. P(v), for obtaining the same interfacial area of bubbles per liquid volume, was also lower than those for other types of aeration columns. It was suggested from the measurement of bubble diameter that the larger interfacial area generated in the HFM aeration column ascribes to the larger gas holdup than the smaller D(vs).
提出了一种新型的鼓泡塔，称为中空纤维膜（HFM）鼓泡塔，其特点是使用中空纤维膜，并在塔内产生高气泡密度。通过改变膜表面来使孔径更小，从而提高了 k(L)a 值。在表观气速为 0.02 m s(-1)至 0.065 m s(-1)的范围内，气泡的 Sauter 平均直径（D(vs)）为 2.0 +/- 0.1 mm，而在表观气速为 4.0 x 10(-4) m s(-1)时，靠近膜的气泡的直径为 811 µm。这种差异归因于气泡聚并的影响。K(L)a 值与表观气速成正比增加，直至 0.02 m s(-1)，超过 0.03 m s(-1)后几乎保持不变。k(L)a 的最大值为 2.5 s(-1)，高于以前报道的其他鼓泡塔的值。为了获得相同的 k(L)a，单位液体体积的气动功率消耗（P(v)）在 HFM 鼓泡塔中最小。为了获得相同的单位液体体积的气泡界面面积，P(v)也低于其他类型的鼓泡塔。通过测量气泡直径发现，在 HFM 鼓泡塔中产生的较大的界面面积归因于较大的气含率，而不是较小的 D(vs)。
