Electrothermal performance of an activated carbon honeycomb monolith

• Published in: Chemical engineering research & design 2012-11, Vol.90 (11), p.2013-2022
• Main Authors: Ribeiro, R.P.P.L., Grande, C.A., Rodrigues, A.E.
• Format: Article
• Language: English
• Subjects: Activated carbon; Adsorption; Applied sciences; Chemical engineering; Chemical engineers; Design engineering; Electric Swing Adsorption (ESA); Electricity; Exact sciences and technology; Heat and mass transfer. Packings, plates; Heating; Honeycomb; Joule effect; Monolith; Swing
• ISSN: 0263-8762
• DOI: 10.1016/j.cherd.2012.03.010

▸ Lower electrical resistance experimental setups allow lower energy losses. ▸ Adsorbent packing configuration has direct influence on the heating efficiency. ▸ Heating efficiency of 52% was obtained employing an average electric power of 293W. ▸ Scale-up considerations show that the heating efficiency can be increased to 83%. The main advantage of Electric Swing Adsorption (ESA) process is related to the fast heating rates that can be achieved by Joule effect. Since this heating is done by passing electricity, its utilization should be efficient to reduce the overall losses of the system. This work discusses the heat transfer phenomena of an Electric Swing Adsorption (ESA) process in order to improve the overall energetic efficiency of the unit. Experiments were done with an activated carbon honeycomb monolith and testing different electrodes and column arrangements. The experimental set-up with lower electrical resistance has shown lower losses: faster heating rates can be achieved and less heat is lost by natural convection to the surroundings. Brass electrodes employed with a Teflon® support have resulted in lower energy losses. Results obtained in a laboratory-scale unit allowed a heating efficiency of 52% employing an average power of 293W. Most of the energy losses were to the electrodes and surroundings, reason why if the process is scaled-up, the efficiency of the unit should be better. Furthermore, the mass of adsorbent/mass of electrodes ratio can be reduced and then the overall efficiency can be increased up to 83%.