B. The diameter of the release pipe. On the premise of
determining the optimal working condition, change the diameter of the
release pipe (20, 25, 32 mm) and conduct the test (the test process is
the same as A). The influence of the diameter of the release pipe on the
particle size distribution of microbubbles was clarified, and the
diameter of the release pipe when the particle size of microbubbles was
concentrated was determined.
C. The shape of the release pipe (straight or elbow). Select
the optimal parameters determined in the above tests and set straight
type and elbow type release pipe (with the same straight-line length) as
the investigation factor for the test (the test process is the same as
A). The influence of different types of release pipe on the particle
size distribution of microbubbles was analyzed, and the appropriate type
of release pipe was selected.
Based on the test results of A, B and C, the optimal operating
conditions (pressure, gas-liquid ratio, release pipe’s length, diameter,
and type) of the device were determined. The dynamic video of the
floating process of microbubbles was observed under the optimal
conditions. The clear single microbubble and microbubble combination
were selected as the capture objects, and the floating process of the
capture objects at the same time was tracked. The kinematic parameter
curves (velocity, acceleration, and displacement) of the capture objects
were obtained by the high-speed photography system. According to the
kinematic parameter curve, the motion state of the single microbubble
and the combination was analyzed, the correlation between the particle
size of the microbubble and the rising rate was revealed, and the
relationship between the particle size of the single microbubble, the
particle size of the combination and the rising rate was established.