Thermal Degradation and Kinetics of Rice Husk

Abstract

The trend for material and energy recovery from biomass-waste along with the need to reduce green house gases has led to an increased interest in the thermal processes applied to biomass. The thermal process applied to biomass produces either liquid fuel (bio-oil) or gaseous fuel. One of the biomass wastes that are produced in Tanzania is rice husk. It can be used either in pyrolysis and gasification process. In order to undertake a parametric study on the fast pyrolysis of rice husk, it is imperative to establish its thermal characteristics. The paper reports thermal degradation and kinetics of rice husk. The thermal degradation was conducted in a thermo-gravimetric analyzer from room temperature to 1273 K at different heating rates. The rice husk was observed to be suitable for gasification since it contains high ash content of 22.21% and fixed carbon of 12.60%. The suitable heating rate for high degradation of rice husk is 10 K/min, which has peak temperature at 633 K. The resulting activation energy of 180.075 kJ/mol and pre-exponential factor of 2.401E+27 s-1 was determined.

Keywords

• Gasification; Kinetics; Pyrolysis; Rice husk; Thermal degradation

Kaynakça

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