Intensification of desorption processes by use of microwaves – an overview of possible applications and industrial perspectives
Special Symposium - EPIC-1: European Process Intensification Conference - 1
EPIC-1: Alternative Energy Forms & Transfer Mechanisms (AE)
Keywords: desorption, process intensification, microwaves, adsorptive reactors
Abstract
Desorption is a significant part of numerous integrated or complex processes e.g. such as: reactions carried out in adsorptive reactors, removal of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) or soil remediation. A selective and efficient desorption influences significantly a final efficiency of the above mentioned entire processes.
A several methods of desorption is applied in a laboratory as well as in industrial practice – e.g. in adsorptive reactors the following methods are applied for regeneration of adsorbent: pressure swing adsorption, temperature swing adsorption and reactive regeneration. Particularly, the pressure swing adsorption is very common, but its application becomes inconvenient and less efficient for processes carried out at low operating pressure, because additional compressors and vacuum pumps should be used in this case.
An alternative temperature swing adsorption-desorption method is not sufficiently efficient due to a large heat capacity of solid bed containing the adsorbent in comparison to the heat capacity of gas heated up this bed. This limitation is also crucial for a desorptive soil remediation or for VOCs and HAPs removal processes. Therefore, an intensification of temperature desorption processes is still important from practical point of view.
Among others, application of microwaves for fast and efficient heating up of the adsorbent bed for its regeneration is considered and tested.
In this work, an extensive literature review, which reports recent contributions to intensification of desorption processes by use of microwaves is given. Basing on more than 30 papers published mostly during last 5 years, some general conclusions and indications can be formulated. It has been found that, particularly for polar compounds a microwave desorption is a very promising method and can be a reasonable alternative for the conventional temperature swing adsorption-desorption method. Thinking about possible industrial applications, due to a limited penetration depth of microwaves into a solid body of the adsorbent, rather continuous then batch processes should be considered. Research areas, which may make a significant impact in future applications of microwaves are put forward.
Presented Wednesday 19, 12:00 to 12:20, in session EPIC-1: Alternative Energy Forms & Transfer Mechanisms (AE).
