Differentprocessesandstepsinvolvedareshownin Fig. 2. Hot
spent washhastobecooledtoabout37 1C bypassingthrougha
plate typeheatexchanger,sincethedigesterislarge;ithasa
certain amountofstabilitytoabsorbtemperature fluctuations fora
few dayswithoutaffectingthedigestertemperature.TheBiogas
cleaner isabiological filter wheretheBacteriaofTiobasillisfamily
convertsH2S tosulphur,mainlysulphatesandfreesulphur.During
the scrubbingandtheH2S removalbiogasbecomes100%humidi-
fied so,ithastobedriedbeforeentrancetoengine.Forthis
purpose thegasiscooledfrom38 1C to121C inatabularheat
exchangerbyusingchilledwater.Moistercondensesandgets
separated.CleanbiogasisthenusedtooperateGEJenbacher
engines of8MWinstalledcapacity.Exhaustgaseswithatem-
peratureofabout500–550 1C areusedtoproducesteaminthe
speciallydesignedboilerswithatotalsteamgenerationcapacityof
5.6 t/hr.