Khalsa, JHA, Leistner, D, Weller, N et al. (2 more authors) (2016) Torrefied Biomass Pellets—Comparing Grindability in Different Laboratory Mills. Energies, 9 (10). ISSN 1996-1073
Abstract
The firing and co-firing of biomass in pulverized coal fired power plants around the world is expected to increase in the coming years. Torrefaction may prove to be a suitable way of upgrading biomass for such an application. For transport and storage purposes, the torrefied biomass will tend to be in pellet form. Whilst standard methods for the assessment of the milling characteristics of coal exist, this is not the case for torrefied materials—whether in pellet form or not. The grindability of the fuel directly impacts the overall efficiency of the combustion process and as such it is an important parameter. In the present study, the grindability of different torrefied biomass pellets was tested in three different laboratory mill types; cutting mill (CM), hammer mill (HM) and impact mill (IM). The specific grinding energy (SGE) required for a defined mass throughput of pellets in each mill was measured and results were compared to other pellet characterization methods (e.g., durability, and hardness) as well as the modified Hardgrove Index. Seven different torrefied biomass pellets including willow, pine, beech, poplar, spruce, forest residue and straw were used as feedstock. On average, the particle-size distribution width (across all feedstock) was narrowest for the IM (0.41 mm), followed by the HM (0.51 mm) and widest for the CM (0.62 mm). Regarding the SGE, the IM consumed on average 8.23 Wh/kg while CM and HM consumed 5.15 and 5.24 Wh/kg, respectively. From the three mills compared in this study, the IM seems better fit for being used in a standardized method that could be developed in the future, e.g., as an ISO standard.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/). |
Keywords: | Grindability; torrefied biomass; pellet; energy consumption; co-firing |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Energy Research Institute (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 20 Oct 2016 09:41 |
Last Modified: | 05 Oct 2017 15:39 |
Published Version: | http://dx.doi.org/10.3390/en9100794 |
Status: | Published |
Publisher: | MDPI |
Identification Number: | 10.3390/en9100794 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:106206 |