DESCRIPTION

Technical Description

During stirring, the continuous phase is liquid. With CE 320, the production of solutions (solid dissolved in liquid), emulsions (mixture of immiscible liquids) and suspensions (insoluble solid in liquid) can be investigated.

Mixing takes place in a tank which is resistant to chemicals and heat-resistant. With the high-performance stirring machine even high-viscosity mixtures can be produced. The speed is adjustable. The torque is indicated on the unit’s digital display. This enables the power demand to be determined.

Nine different, easily interchangeable stirrers are provided. With plastic balls which are dispersed in the water it is possible to observe the characteristic flow fields of the different stirrer types. Flow impeders can be inserted in the tank to investigate their influence on the mixing process. To determine the mixing time and mix quality of solutions, a conductivity meter is available. The device can also be used to measure temperatures.

A removable coiled tube serves as a heat transfer medium. It can be used for heating or cooling with water from the laboratory supply. A valve with precise adjustment is used to adjust the flow rate. This enables the influence of mixing processes on heat transfer to be investigated.

The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments

- flow fields of various stirrer types
- power demand, mixing time, mix quality dependent on
  * stirrer type
  * speed
  * materials used (density, viscosity)
  * insertion of flow impeders
- observation of the suspension state of suspended solids when using different stirrers and at different speeds
- observation of the droplet size of emulsions when using different stirrers and at different speeds
- influence of mixing processes on heat transfer