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1、CHAPTER-IINTRODUCTIONTheenergyeconomylinkagesplayaverydecisiveroleindeterminingthedevelopmentpathofadevelopingnation.Withtheever-increasingpopulation,theinterconnectedproblemsfacedbythedevelopingcountriesarefood,fuelandfertilizers.Asfarasfuelisconcerned,theruralpopulationisst
2、illheavilydependentonthetraditionalfuelssuchasfirewood,animalwastesandagriculturalresidues.Thetotalenergydemandisincreasingdaybyday.Theincreasingdemandsarereflectedinexcessivewoodconsumption,intheshorttermandtheerosionofagriculturalland,inadequatefoodsupply,permanentclimatech
3、angeandreducedwateravailability,inthelongterm(Kashyapetal2003).Energysourcescanbebroadlyclassifiedintotwocategories,namelynon-renewableandrenewablesources.Sourceslikecoal,power,oilandgasthatcannotberenewedarethenon-renewablesources.Solar,wind,biomassandwaterthatregenerateitse
4、lfaretherenewablesourcesofenergy.Therehasbeenanincreasedinterestinthedevelopmentoftechnologiesforexploitingrenewableenergysourcessuchasbiomassforenergy/powergenerationeitherdirectlyorindirectlythroughvariousconversionroutesastheagriculturalwastespossessalarge,unutilizedenergy
5、potential.Annualbiosynthesisofcellulosebybothlandplantsandmarinealgaeoccursatarateof0.85x1011tonnes/annumequivalenttomorethan4timestheworld’syearlytotalenergyconsumption(Nowaketal2005,Sarataleetal2008).Plantresiduesgenerallyhaveahighcontentofcellulosewhichhascombustionenergyo
6、f15kJ/gandifconvertedtomethane,apreferredfuel,hasacombustibleenergyof50kJ/g(Khanetal1983).Directcombustionofbiomassforheatandpowergenerationisthemostcommonwayofutilizingbiomassforenergy(Parawiraetal2008).Biogasgeneratedviaanaerobicdigestionhasprovedtobecompetitivewithheat(via
7、burning),steamandethanolproductioninefficiency,costandenvironmentalimpactoftheconversionofwastetoenergy(Chynowethetal2001,Edelmannetal2000).Lignocellulosicbiomassisdefinedascontemporaryplantmatter(FrankandSmith1988)whichiscontinuouslyreplenishedbythephotosyntheticreductionofc
8、arbondioxide(CO2)bysunlightenergy(ZhangandLynd2004,Ragauskasetal2006
