Superficial Velocity - the Key to Downdraft Gasification
نویسندگان
چکیده
A low SV causes relatively slow pyrolysis conditions at around 600°C, and produces high yields of charcoal 20-30%, large quantities of unburned tars, and a gas with high hydrocarbon content and high tar (volatile) content. A high SV causes very fast pyrolysis, producing less than 10% char-ash at 1050 C and hot gases at 1200-1400 C in the flaming pyrolysis zone. These gases then react with the remaining char-ash to yield tars typically less than 1000 ppm, 5-7% char-ash and a producer gas with less energy.
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