ENHANCED GEOMETRIES FOR DIRECT CONTACT MEMBRANE DISTILLATION

Open Access
Author:
Goldberg, Jonathan Bendl
Area of Honors:
Mechanical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Alexander Rattner , Thesis Supervisor
  • Sean Brennan , Honors Advisor
Keywords:
  • Membrane Distillation
Abstract:
Membrane distillation is an emerging technology that was developed in the 1980s to provide a low electricity-intensity approach to concentrated fluid separation. Most notably, the method has gained industrial and academic attention for its promise in water desalination applications, which would benefit communities and companies with limited access to fresh water. Several major drawbacks of the technology have delayed its mainstream adoption. This thesis seeks to enhance performance of the direct contact configuration of membrane distillation (DCMD). A challenge with DCMD is the need for exceedingly large setups due to the requirement for substantial membrane surface area. It is postulated that by manipulating the feed channel geometry, solution side mixing can be enhanced and the mass transfer rate of the process can be improved, thus increasing the viability of the technology. In order to test this postulate, a DCMD channel was modeled in the multiphysics simulation program COMSOL. Several enhanced channel geometries were evaluated and their mass transfer rates were compared to the results from a plain channel. While the changes to the feed side proved successful at increasing mass flux to the extent of 13.7%, this benefit was accompanied with an increase to the pressure drop penalty of 660%. The implications of this study and several ways to improve upon the investigation are suggested in the conclusion section.