Authors:

Ansh Mishra

Date Created:

Not specified

Course Title:

Professor:

Not specified

About Paper:

Heat pump-based drying processes are gaining attention as a potential technology because of their high efficiency and electrification. However, the heat pump-based drying processes are still energy intensive due to excessive cooling for dehumidification and reheating of the process air. Vapor selective membrane technology is one way of eliminating the energy penalty to improve the efficiency of heat pump drying processes. The vapor selective membranes have a dense hygroscopic active layer and a porous hydrophobic support layer. The hygroscopic nature of the active layer is used to segregate vapor particles from humid air and the support layer is used to provide mechanical strength and stable structure to the membrane. Consequently, air dehumidification can be performed by eliminating the energy penalty associated with cooling and reheating the air in heat pump drying processes. However, determining a membrane having the desired properties is challenging and needs further scrutiny. This work focuses on fabricating high-performance vapor selective membranes by utilizing various materials for the active layer coating and comparing membrane performances to establish an optimal membrane for industrial dehumidification applications. NEXAR, Polybenzimidazole (PBI), PEBAX 1657, Graphene Oxide, Polyvinyl Alcohol (PVA), and Poly-Ether-Ether-Ketone (PEEK) are promising polymer candidates considered for this work. Vapor permeability, nitrogen permeability, H2O/N2 selectivity, and thermal conductivity are characterized in detail. In addition, the difference in active layer thickness is studied to understand how it affects membrane performance and is observed through scanning electron microscope imaging. A general framework for membrane fabrication and characterization of various polymer materials is presented.

Source:

Purdue University / 2023

Topics:

No topics listed

Co-authors:

Ansh Mishra