Untersuchungen zur Herstellung und zum Abbrandverhalten von Wirbelschichtpyrolysekoksen [report]

C. Leick, S. Rumpel, S. Bürkle, E. Henrich, W. Leuckel
1997
Die an der Thermowaage bestimmten Reaktivitäten der Kokse werden vergleichend in einem Arrhenius-Diagramm (T=250-600°C} dargestellt. Nach steigender Reaktivität geordnet lautet die Reihenfolge der untersuchten Kokse: Steinkohlenkoks < Braunkohlenkoks < DSD-Koks < Holzkoks < Strohkoks. Durch die an der Thermowaage bestimmten Reaktivitätsunterschiede zwischen Pyrolysekoksen und Bettmaterial ist ein selektiver Abbrand der Pyrolysekokse beim Betrieb einer kontinuierlichen Kokswirbelschicht zu
more » ... belschicht zu erwarten. Abstract Preparation and combustion behaviour of cokes from fluidized bed pyrolysis Abstract The partial and selective combustion of coke formed by pyrolysis of waste materials could provide the heat to run a fluidized bed of hard coal char for pyrolysis or gasification purposes in an autothermal mode. Therefore the reactivity of various cokes and coal chars has been studied in two Iab-scaie facilities (thermobalance, fluidized bed) in the chemical regime. The cokes usually have been obtained by pyrolysis in a fluidized bed of sand. To calculate the kinetic parameters as activation energy EA and collision factor k 0 , the mass loss during combustion has been determined in a thermobalance. ln case of the fluidized bed experiments the CO/ C02-concentrations in the off-gas have been used to calculate the mass loss of carbon during combustion. The evaluation of the kinetic parameters has been done in the same way as for the thermobalance. A mass related reaction rate assuming a reaction order of one as regards mass of carbon and of u as regards oxygen-concentration has been used for data analysis.
doi:10.5445/ir/270042244 fatcat:7xnepyhegvg2poqmsrw44qtoda