Measurement of solids holdup in a three-phase fluidized bed by an ultrasonic technique

Prediction of gas holdup in a three-phase fluidized bed from bed pressure drop measurement

“…Considerable work has been carried out on the gas holdup in three-phase fluidized columns. Various aspects of these fluidized beds have been reviewed by several investigators (Catros et al, 1985;Epstein, 1981;Kato et al, 1981;Kim et al, 1975;Muroyama and Fan, 1985;Fan, 1989;Okamura et al, 1989;Han et al, 1990;Lee and Lasa, 1987;Lee et al, 2001;Safoniuk et al, 2002;Song et al, 1989;Yu and Kim, 1986), which include the importance of gas holdup and various factors affecting it.…”

Non-invasive imaging of liquid/gas flow using ultrasonic transmission-mode tomography

“…Examples of ultrasonic techniques for differentiating three-phase components in gas-liquid-solid system are the use of ultrasonic signal analysis method [9][10][11] and multi-frequency ultrasonic technique [12].…”

Acoustic Probe for Solid-Gas-Liquid Suspension

“…1.3 Measurement Techniques in Three-phase Systems: Okamura et al (1989) and Uchida et al (1989), in two related works, used the degree of phase difference between acoustic signals obtained in liquid, solid-liquid, and three phase systems to empirically determine the concentration of solids in three phasereactors. The main premise of their work was that the presence of the gas phase did not affect the phase shift of the signal received which was induced due to the presence of the solid particles alone.…”

“…Therefore, this technique is essentially measuring the solids hold up in a two phase system. Soong et al (1995) used a technique based on that of Okamura et al (1989) to perform ultrasonic measurements of the solids concentration in a three phase slurry consisting of water, nitrogen bubbles, and glass beads. Particular attention was placed on the effects of the gas flow.…”