Therefore, most biomass fuels, regardless of origin, produce torrefied products with similar properties—with the exception of ash properties, which largely reflect the original fuel ash content and composition. Hydrophobic behavior: :Torrefied biomass has hydrophobic properties, i.e., repels water, and when combined with densification make bulk storage in open air feasible. Elimination of biological activity: :All biological activity is stopped, reducing the risk of fire and stopping biological decomposition like rotting.
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The higher energy density means lower transport costs, and a decrease in transport- related GHG emittance. The IEA (International Energy Agency) has calculated energy and GHG costs for regular and torrefied pellets/briquettes. When making pellets and shipping them from Indonesia to Japan, a minimum of 6.7% energy savings or 14% GHG savings is expected when switching from regular to torrefied. This number increases to 10.3% energy savings and 33% GHG savings when making and shipping minimum 50mm briquettes instead of pellets (briquette production requires less energy).
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The final product is the remaining solid, dry, blackened material that is referred to as torrefied biomass or bio-coal. During the process, the biomass typically loses 20% of its mass (bone dry basis) and 10% of its heating value, with no appreciable change in volume. This energy (the volatiles) can be used as a heating fuel for the torrefaction process. After the biomass is torrefied it can be densified, usually into briquettes or pellets using conventional densification equipment, to increase its mass and energy density and to improve its hydrophobic properties.
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This traditional use of biomass is being replaced by liquid petroleum gas in rural areas, resulting in increased burning of biomass in fields, This has become a major source of air pollution in nearby towns and cities. ;Torrefied biomass Large quantities of imported coal are being used in pulverised coal-fired power stations.
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If the grain is curly, with flame or quilt patterns, it's usually reserved for more expensive instruments. In high-end guitars this wood is sometimes Torrefied to cook out the Lignin resins, allowing the greater stability to climate & environmental changes, and to enhance its tonal characteristics as the instrument's resonance is more evenly distributed across the cellulose structure of the wood without the lignin.
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More homogeneous composition: :Torrefied biomass can be produced from a wide variety of raw biomass feedstocks that yield similar product properties. Most woody and herbaceous biomass consists of three main polymeric structures: cellulose, hemicellulose and lignin. Together these are called lignocellulose. Torrefaction primarily drives moisture and oxygen-rich and hydrogen-rich functional groups from these structures, producing similar char-like structures in all three cases.
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This solid product contains approximately 85% of the original biomass energy however. Basically the mass part has shrunk more than the energy part, and the consequence is that the calorific value of torrefied biomass increases significantly, to the extent that it can compete with energy dense coals used for electricity generation (steam/thermal coals). Vaclav Smil states that the energy density of the most common steam coals today is 22–26 GJ/t.
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Raw biomass can not be used in the pulverised coal mills as they are difficult to grind into fine powder due to caking property of raw biomass. However biomass can be used after Torrefaction in the pulverised coal mills for replacing imported coal. North west and southern regions can replace imported coal use with torrefied biomass where surplus agriculture/crop residual biomass is available. Biomass power plants can also get extra income by selling the Renewable Purchase Certificates (RPC).
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Raw biomass is not suitable for use in the pulverised coal mills as they are difficult to grind into fine powder due to caking problem. However 100% biomass can be fired after Torrefaction in the pulverised coal mills for replacing imported coal. Torrefied biomass plants can be integrated with existing pulverised coal-fired power stations using the available hot flue gas as heat source. Cofiring dry biomass up to 20% heat input with coal is also possible directly in pulverised coal-fired power stations without facing caking problem.
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Torrefied and densified biomass has several advantages in different markets, which makes it a competitive option compared to conventional biomass wood pellets. Higher energy density: :An energy density of 18–20 GJ/m³ — compared to the 26 to 33 gigajoules per tonne heat content of natural anthracite coal — can be achieved when combined with densification (pelletizing or briquetting) compared to values of 10–11 GJ/m³ for raw biomass, driving a 40–50% reduction in transportation costs. Importantly, pelletizing or briquetting primarily increases energy density. Torrefaction alone typically decreases energy density, though it makes the material easier to make into pellets or briquettes.
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In order to reduce chlorine (and moisture) content, M. x giganteus is usually harvested dry, in early spring, but this late harvest practice is still not enough of a countermeasure to achieve corrosion-free combustion. However, the chlorine amount in miscanthus reduces by approximately 95% when it is torrefied at 350 degrees Celsius. Chlorine release during the torrefaction process itself is more manageable than chlorine release during combustion, because "[…] the prevailing temperatures during the former process are below the melting and vaporization temperatures of the alkali salts of chlorine, thus minimizing their risks of slagging, fouling and corrosion in furnaces." For potassium, Kambo et al.
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It varies considerably in composition, sometimes being only slightly roasted and consequently only partly converted into dextrine, and at other times being highly torrefied, and almost completely soluble in cold water and very dark in colour. Its thickening power decreases and its gummy nature increases as the temperature at which it is roasted is raised. It is useful for strongly acid colours, and with the exception of gum Senegal, it is the best choice for strongly alkaline colours and discharges. Like the natural gums, it does not penetrate as well into the fibre of the cloth pr as deeply as pure starch or flour and is unsuitable for very dark, strong colours.
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The method slowly becomes popular in other parts of the world, too. In the North America thermo treated wood is often referred to with such trade names as roasted, torrefied or caramelised wood. 1999 – Juha starts co-operation with fellow craftsmen Mika Koskinen and Jiri Kaarmela, who are to become part owners of the company two years later, along with luthier Jarkko Lindholm, who joins the team in 2000, but leaves a year later to work on his own Lindholm Musical Instruments. Juha designs and launches new variations of the Duke theme and introduces another uncommon local material – the Arctic Birch tops. 2000 – Juha designs and launches the second Ruokangas model – VSOP, built of thermo treated Alder and Rock Maple – and attends the Frankfurt Musikmesse for the first time. 2001 – Luthier Jyrki Kostamo joins the Ruokangas team.
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