Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Energy wasted grinding switchgrass smaller to improve flowability

13.04.2010
Biofuels processors who mill switchgrass into fine bits to help its flowability should be able to save time, energy and money by not doing so, a Purdue University study shows.

Switchgrass can be used in a number of biofuel applications, but moving it - especially feeding it into boilers - can be problematic, said Klein Ileleji, an assistant professor of agricultural and biological engineering.

While corn and soybeans are round and spherical, switchgrass is shaped more like matchsticks, causing pieces to interlock and disrupt its ability to flow. Those blockages cost time and can be dangerous for those tasked with breaking the clog, he said.

"In any facility ¨l in a power plant or in a processing facility ¨l when you have a blockage, it's a processing nightmare," said Ileleji, whose findings are in the current issue of the journal Transactions of the ASABE.

Ileleji compared circularity, roundness and aspect ratio for corn, soybean and switchgrass that had been hammermilled to three different sizes. Aspect ratio, which has the greatest effect on the ability of switchgrass to flow, is the ratio of a switchgrass particle's length to its width.

Conventional wisdom held that grinding switchgrass into smaller pieces would bring its aspect ratio closer to that of corn and soybeans, which have ratios close to 1 and no problems with flowability.

"Switchgrass is not a good flowable feedstock. You would think grinding it smaller would help," Ileleji said. "But grinding does not necessarily change the morphological characteristics in switchgrass that are important for flow."

Ileleji's testing showed that hammermilling - one of the most common grinding techniques, which beats and breaks biomass until it is small enough to pass through screens - breaks switchgrass in a way that keeps its aspect ratio about the same no matter the size. Unless the switchgrass is milled into a powder, those high aspect ratios would keep causing switchgrass to interlock and clog in bulk flow.

Ileleji said processors could save money with the information because they can stop hammermilling switchgrass when it fits through a 6.4 mm screen, the largest Ileleji tested.

"Grinding consumes a lot of energy. It is one of the highest energy costs in a processing facility," Ileleji said. "It's better to grind switchgrass through a 6.4 mm screen than to use more energy to grind through a smaller screen expecting that its handling characteristics would be improved dramatically."

Ileleji said he would study flow behavior of switchgrass through hoppers to try to find ways to keep it from creating blockages. Duke Energy and the Purdue Energy Center funded his research, which is part of his doctoral student Cedric Ogden's research on the flow mechanics of switchgrass bulk solid in hoppers under gravity discharge.

Abstract on the research in this release is available at: http://www.purdue.edu/newsroom/research/2010/100412IelejiMorphology.html

Brian Wallheimer | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Agricultural and Forestry Science:

nachricht Six-legged livestock -- sustainable food production
11.05.2017 | Faculty of Science - University of Copenhagen

nachricht Elephant Herpes: Super-Shedders Endanger Young Animals
04.05.2017 | Universität Zürich

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>