BASIC DATA ON BIOGAS - Energikontor Sydost

Terms and unitsSwedish Gas Centre: Basic Data on BiogasAnaerobicCalorific valueCBGLBGLELMethane numberNm 3Pressurised water dewpointRelative densityUELWobbe indexOxygen freeEnergy released during combustion. Lower andupper calorific values can be defined. The lowercalorific value (used mostly in Sweden) gives theenergy released when the water vapourgenerated during combustion is still in the gasphase. The upper calorific value includes theenergy released when water vapourcondensates.Compressed biogasLiquefied BiogasLower Explosion LimitDescribes the gas resistance to knocking in acombustion engine. By definition, methane has amethane number of 100 and carbon dioxideincreases the number.Normal cubic meter. Volume at normalconditions, 273.15 K (0°C) and 1.013 bar(atmospheric pressure).The temperature at a given pressure at whichwater vapour in the gas condenses.Density of the gas divided by the density of air.Upper Explosion Limit.Defined as the calorific value divided by thesquare root of the relative density. As with thecalorific value, there is an upper and lowerWobbe index.20