[ps2id id=’background’ target=”/]
BACKGROUND
Mixing can be defined as a process that tends to result in randomization of dissimilar particles within a system.
Mixing may refer to the random distribution into or through one another of two or separate phases.
Mixing devices are technically called an impeller. Impellers are classified on the basis of the sample and pitch of the blades that are attached to the central shaft. Three main types of impellers are used namely propellers, turbines and paddles.
Vortex is formed when mixing device is placed in a mixing container in a symmetrical position. Vortex can be prevented by avoiding symmetry. In this experiment, mixing device is placed in centre, off centre, and inclined positions to observe formation/disappearance of vortex. Relative intensity of vortex formation is recorded.1,2
Aim: To determine the mixing efficiency when the propeller blade is introduced in different positions.
[ps2id id=’requirements’ target=”/]
REQUIREMENTS
Apparatus: Beakers
Weighing balance
Propeller mixer
Stop watch
[ps2id id=’procedure’ target=”/]
PROCEDURE
Purified water (200 ml) was placed in a 500 ml beaker. Hundred gram of sucrose was weighed and added into water. Immediately motor driven shaft carrying propeller was placed in the beaker centrally. The propeller was allowed to rotate on it’s own axis at high rpm. The time was noted. The time required for complete dissolution of sugar was noted. The motor was put off, propeller was removed, the sugar solution was removed and the propeller was washed. By placing the propeller off-centrally, steps 1 to 7 were repeated. By placing the propeller inclined, steps 1 to 7 was repeated. The best position of propeller for dissolution of sugar was inferred on the basis of observations.
[ps2id id=’conclusion’ target=”/]
CONCLUSION
The mixing efficiency of sucrose is ___________
[ps2id id=’references’ target=”/][ps2id id=’1′ target=”/]
REFERENCES
- Subrahmanyam CVS, Setty JT, Suresh S. Laboratory manual of pharmaceutical engineering (Unit operations). Delhi Vallabh Publications.
-
Pharmaceutical Engineering by Sanbamurty K. (New Age International, New Delhi)Cooper and Gunn’s Tutorial Pharmacy Edited by Carter SJ. (CBS Publishers, Delhi).
