Effect of process variables on the density and durability of the pellets made from high moisture corn stover

Jaya Shankar Tumuluru

Research output: Contribution to journalArticlepeer-review

148 Scopus citations

Abstract

A flat die pellet mill was used to understand the effect of high levels of feedstock moisture content in the range of 28-38% (w.b.), with die rotational speeds of 40-60Hz, and preheating temperatures of 30-110°C on the pelleting characteristics of 4.8mm screen size ground corn stover using an 8mm pellet die. The physical properties of the pelletised biomass studied are: (a) pellet moisture content, (b) unit, bulk and tapped density, and (c) durability. Pelletisation experiments were conducted based on central composite design. Analysis of variance (ANOVA) indicated that feedstock moisture content influenced all of the physical properties at P<0.001. Pellet moisture content decreased with increase in preheating temperature to about 110°C and decreasing the feedstock moisture content to about 28% (w.b.). Response surface models developed for quality attributes with respect to process variables has adequately described the process with coefficient of determination (R2) values of >0.88. The other pellet quality attributes such as unit, bulk, tapped density, were maximised at feedstock moisture content of 30-33% (w.b.), die speeds of >50Hz and preheating temperature of >90°C. In case of durability a medium moisture content of 33-34% (w.b.) and preheating temperatures of >70°C and higher die speeds >50Hz resulted in high durable pellets. It can be concluded from the present study that feedstock moisture content, followed by preheating, and die rotational speed are the interacting process variables influencing pellet moisture content, unit, bulk and tapped density and durability.

Original languageEnglish
Pages (from-to)44-57
Number of pages14
JournalBiosystems Engineering
Volume119
DOIs
StatePublished - Mar 2014

Fingerprint

Dive into the research topics of 'Effect of process variables on the density and durability of the pellets made from high moisture corn stover'. Together they form a unique fingerprint.

Cite this