ENHANCEMENT OF THE ENERGY DENSITY OF RICE HUSK THROUGH DRY AND CHEMICAL TREATED TORREFACTION

GETAYE, AYTENEW

dc.contributor.author	GETAYE, AYTENEW
dc.date.accessioned	2020-03-18T05:57:56Z
dc.date.available	2020-03-18T05:57:56Z
dc.date.issued	2020-03-18
dc.identifier.uri	http://hdl.handle.net/123456789/10589
dc.description.abstract	Despite all its advantages biomass has some shortcomings that often create difficulties in its wide scale use as an energy source. Compared to other fuels like coal, biomass has higher oxygen content, lower calorific value, low energy density, lower bulk density, higher hygroscopic nature, and higher moisture content. Thus, biomass faces some technical challenges in energy conversion systems. Torrefaction is a technology that a partial pyrolysis of biomass which is carried out under atmospheric pressure in a narrow temperature range of 200-300°C and under an inert environment which yields higher solid yield than pyrolysis. Torrefaction of biomass significantly changes its physical and chemical properties like moisture content, density, grind ability, pelletability, hydrophobicity, CV, proximate and ultimate composition, and storage. The objective of this study was to examine the torrefaction process of lignocellulose biomass rice husk produced in Ethiopia through dry and chemical treated torrefaction. Three different torrefaction temperatures 230, 255 and 2800C with three different holding times 20, 40 and 60 minutes were considered. The result showed that a net reduction of the volatiles content, mass yield, moisture content, bulk density and atomic oxygen content correlate with increasing torrefaction temperature and reaction time, while atomic carbon content, higher heating value(HHV),fixed carbon content and energy density increase with higher torrefaction temperatures and time in both treatment cases. So, torrefaction temperature and holding time had a significant effect on torrefaction process of rice husk. Based on the findings of this study, temperature of 280 with a residence time of 60 min for dry torrefaction and temperature of 280 and a residence of 40 min for chemical treated torrefaction could be suggested for an effective and proper torrefaction process to recycle the agricultural biomass. The energy density of dry torrefaction was enhanced by 120% and for chemical treated torrefaction it was enhanced by 127.4%. From the thermo gravimetric analysis TGA, torrefaction peaks were observed at temperatures between 200-3000C.The pyrolysis peaks appeared as a result of the degradation of rice husk. Therefore, the torrefied biomass becomes fuel sources which can be applied to replace with fossil fuel.	en_US
dc.language.iso	en	en_US
dc.subject	Energy Center	en_US
dc.title	ENHANCEMENT OF THE ENERGY DENSITY OF RICE HUSK THROUGH DRY AND CHEMICAL TREATED TORREFACTION	en_US
dc.type	Thesis	en_US