There are a number of techniques that were used to figure out
the quantitative & qualitative analysis of the solid-liquid mixing process.
In solid-liquid mixing process, main measuring parts are the solid suspensions
& measurement of Njs. For understanding the level of suspension of
solids in liquid, conductivity technique, optical technique, tomography
technique, and sampling techniques are generally used. Whereas for the finding
of Njs, visual technique, ultrasonic Doppler flowmeter probe, and
conductivity probe normally used.
Visual techniques: Most important method to find out the Just suspended speed
roughly. Also, it is useful to learn the degree of homogeneity. Visual
observations are most important because it gives a rough idea to find out the
place the other equipment for further processing. Visual observation helps to
find out the proper sampling areas. Handling the high concentration of solids
creates the problems for visual observations. Addition of colored Dye in the
reactor will take up by liquid/ solid help to guide the process observations.
Photographs and videos are taken for qualitative analysis.
Conductivity probe: To measure solid concentration in a more accurate way, conductivity
probe is used in a system containing suspended liquid is conducting &
suspended solids are non-conducting in nature. But conductivity probe only measures
the solids concentration in liquid & it cannot separate for the different
particle size. Placing of the probe on reacting tank should be proper that it
cannot affect the flow pattern of fluid. As the probe is obtrusive, it’s better
to look for separation of solids were the probe is placed. If there is no sign
of separation of solids from liquid, then it suggests that concentration is not
going to change. But there is some kind of separation of solids occur near the
place where the probe has been placed, then the measured value the for solid a
concentration is low. In, such cases, highest value will take as the final
value for study.