(52b) Use of a Scale Model Membrane Filtration System as a Small Scale Laboratory Demonstration

The University of Arkansas Chemical Engineering department has provided local elementary schools, middle schools, Boy Scout groups, Girl Scout groups, and other groups with a demonstration of membrane separation technology. The technology is used to concentrate milk solids for cheese manufacture, to purify drinking water, to concentrate fruit juices, and many other applications. The unit used by the UARK presentation teams consists of a 125 mm square hydrophilic flat membrane housed in an acrylic holder with a feed side pressure gauge, a variable speed pump, a feed tank, and a collection cylinder. The feed is usually either milk or a colorful fruit juice. After a brief explanation of the parts of the system, the system is started by a volunteer who adjusts the feed side pressure to 20-30 psig. The permeate will consist of a colorless solution and is collected into the collection cylinder via clear silicone tubing, while the concentrate is returned to the feed tank via a different clear silicone tubing. While the system runs, the presentation team discusses the application of the technology to various separation problems. Children in K-12 seem to like the system because they can suggest separations and it is flexible enough to make these changes without destroying the membranes.