Sterlitech Corporation teams up with California State Polytechnic University, Pomona

Sterlitech teamed up with Senior Engineering Students at California State Polytechnic University, Pomona (Cal Poly Pomona) to evaluate the design of a tangential flow Air Gap Membrane Distillation (AGMD) test cell. Membrane Distillation (MD) is a thermally driven membrane separation technique used for desalination. In this process, the driving force is the difference in the vapor pressure on both sides of the membrane, where permeate travels through a hydrophobic membrane in a vapor phase. Advantages of MD process over conventional distillation or pressure driven separation processes are:

• Low Operating Pressures
• Low Operating Temperatures
• Less Susceptibility to Fouling

These all translate to lower energy requirements that make MD an energy efficient separation process. Scope of the Project: A bench-scale tangential flow test cell is configured in this project where feed solution is circulated tangentially to the membrane in the feed channel on one side and the coolant solution is circulated tangentially to a cold plate in the cooling channel on the other side. There is an air gap between the membrane and the cold plate. The thickness of the air gap can be varied. In this configuration, permeate travels through the membrane and is collected at the bottom of the air gap. Objectives of this project included the design of the air gap configuration, as well as evaluating the effect of air gap thickness and operating temperatures on the permeate flux and permeate quality. 

Results and Final Presentation Spacer plates were designed to create an air gap of 3/16 in (4.76 mm) and a membrane active area of 7.068 in² (179.5 mm²) in the cell. Permeate flux measured with this configuration was within the range expected for the membranes and operating conditions tested in this project. Permeate was collected at the bottom of the air gap. Feed temperature and flow rate both proved to effect the permeate flux and quality. The results obtained in the course of this project were presented at the Spring Green Expo of 2016 held by The Metropolitan Water District of Southern California. Spring Green Expo highlights sustainability and water related projects created by Southern California college students. If you have additional questions or would like to learn about the AGMD cell or membranes recommended for the MD process, please contact Sterlitech.

Congratulations to the group members at Cal Poly Pomona for delivering the project and presenting at the Spring Green Expo!   Pictured: Senior Design Project Group members at Spring Green Expo 2016. N. Espinoza, B. Elgawly, and M.Price.