Topic 2: Rapid Mix
In this experiment students investigate the significance of rapid mixing in terms of turbidity removals using optimum coagulation conditions from the previous experiment. The students are presented with current conventional and opposing rapid mix theories. Following a group discussion, students are guided in the design of an experiment to test the theories. This is a great way to introduce the students to design of experiments. Factors such as mixing intensity and duration are investigated at different levels and under different coagulation mechanisms. Students then use statistical tools to determine whether the observed effects are statistically significant.
Examples of some results obtained by the students are shown below: