A model for simultaneous measurement of gas and solid holdups in a bubble column using ultrasonic method

Abstract

AbstractThe ultrasonic method developed to measure the dispersed phase holdups in dispersion systems is based on the fact that the velocity of ultrasound in the dispersion is different from that in the liquid. The relationships between velocity differences in the term of transmission time differences of ultrasound and gas holdup in a gas‐liquid system and solid holdup in a liquid‐solid system were derived. The holdups became linearly dependent on the time differences, which is in agreement with the experimental data. Based on those relations, a model for simultaneous measurement of gas and solid holdups in three‐phase systems is proposed. The model permits measurement of the dispersed phase holdups by measuring the transmission time of ultrasound transmitted through the dispersions in two frequencies. It allows investigation of local holdups distributions in a bubble column and in a suspended bubble column.