hectare Energy • There are different ways of getting the energy out of a wood: –Traditional burning –The gasification of wood The calorific values • The calorific values, in terms of 20% of moisture regain: alder – 700 kWh/ton birch – 1500 kWh/ton Wood gas • Wood gas is produced by heating biomass (wood) in a temperature over 700°C without air access or in a method of pyrolysis. Wood gas consists of carbon dioxide, methane and carbon monoxide. The calorific value of wood gas is approximately 1,25 MWh/1000 m³ wood. 34...40 m³ of wood gas can be produced out of a 100 kg of wood Biomass from nature protection area • Ecologically pure • Low cost • Sustainable Biomass from nature protection area – an environmental friendly input for biogas Jaak-Albert Metsoja Nature Conservation Society “Eagle”
mixing with sediments and being buried under anoxic conditions. As further layers settled to the sea or lake bed, intense heat and pressure built up in the lower regions. This process caused the organic matter to change, first into a waxy material known as kerogen, which is found in various oil shales around the world, and then with more heat into liquid and gaseous hydrocarbons via a process known as catagenesis. Formation of petroleum occurs from hydrocarbon pyrolysis in a variety of mainly endothermic reactions at high temperature and/or pressure. There were certain warm nutrient-rich environments such as the Gulf of Mexico and the ancient Tethys Sea where the large amounts of organic material falling to the ocean floor exceeded the rate at which it could decompose. This resulted in large masses of organic material being buried under subsequent deposits such as shale formed from mud. This
g., furfuralde- The Main Groups of Compounds hyde and 5-hydroxymethyl-2-furaldehyde). The phenolic fraction of wood smoke con- Wood smoke contains several aliphatic sists of about 250 components, with 85 of and aromatic alcohols, including methanol, them identified. Phenols are formed primar- ethanol, allylalcohol, n-amylalcohol, benzyl ily due to pyrolysis and oxidation of lignin, alcohol, and phenylethylalcohol. Methanol at comparatively low temperature (200– may be the substrate for the generation of 400°C), and cellulose at 700°C. The total formaldehyde and formic acid. contents of phenols depend on the kind of The group of carboxylic acids in wood wood, temperature, and the density of the smoke consists of about 30 various com- analyzed smoke. According to different data, pounds
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