Dielectric Properties of Biomass/Biochar Mixtures at Microwave Frequencies

Candice Ellison, Murat Sean McKeown, Samir Trabelsi and Dorin Boldor
Additional contact information
Candice Ellison: Biological and Agricultural Engineering, Louisiana State University, 149 E. B. Doran, Baton Rouge, LA 70803, USA
Murat Sean McKeown: College of Engineering, University of Georgia, 597 D. W. Brooks Dr., Athens, GA 30602, USA
Samir Trabelsi: U. S. Department of Agriculture, Agricultural Research Service, Russell Research Center, 950 College Station Rd., Athens, GA 30605, USA
Dorin Boldor: Biological and Agricultural Engineering, Louisiana State University, 149 E. B. Doran, Baton Rouge, LA 70803, USA

Energies, 2017, vol. 10, issue 4, 1-11

Abstract: Material dielectric properties are important for understanding their response to microwaves. Carbonaceous materials are considered good microwave absorbers and can be mixed with dry biomasses, which are otherwise low-loss materials, to improve the heating efficiency of biomass feedstocks. In this study, dielectric properties of pulverized biomass and biochar mixtures are presented from 0.5 GHz to 20 GHz at room temperature. An open-ended coaxial-line dielectric probe and vector network analyzer were used to measure dielectric constant and dielectric loss factor. Results show a quadratic increase of dielectric constant and dielectric loss with increasing biochar content. In measurements on biochar, a strong dielectric relaxation is observed at 8 GHz as indicated by a peak in dielectric loss factor at that frequency. Biochar is found to be a good microwave absorber and mixtures of biomass and biochar can be utilized to increase microwave heating rates for high temperature microwave processing of biomass feedstocks. These data can be utilized for design, scale-up and simulation of microwave heating processes of biomass, biochar, and their mixtures.

Keywords: biochar; biomass properties; microwave applications; dielectric properties; bioenergy (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2017
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (5)

Downloads: (external link)
https://www.mdpi.com/1996-1073/10/4/502/pdf (application/pdf)
https://www.mdpi.com/1996-1073/10/4/502/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:10:y:2017:i:4:p:502-:d:95332

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().