Slow pyrolysis in a rotary kiln reactor : optimization and experiment

• Main Author: Zajec, Luka
• Other Authors: Háskólinn á Akureyri
• Format: Thesis
• Language: English
• Published: 2009
• Subjects: RES. The School for Renewable Energy Science; Renewable energy sources; Orkumál; Meistaraprófsritgerðir; Eldsneytisframleiðsla; Lífræn efnasambönd; Endurnýjanleg orka; Akureyri
• Online Access: http://hdl.handle.net/1946/7005

RES Master´s Thesis Verkefnið er unnið í tengslum við Háskóla Íslands og Háskólann á Akureyri Biomass is the fourth largest source of energy worldwide after coal, oil and natural gas. Among the various technologies encompassing biomass energy conversion, some may be considered to have reached a level of technological development which allows use on an industrial scale while others require further testing to increase yields and reduce costs of energy conversion and management. The thermochemic conversion of biomass (pyrolysis, gasification, combustion) represents the most promising technique for energy production. In this context fits the application of the process of slow pyrolysis of biomass in a rotary kiln reactor with an integrated gas burner of small size for a continuous production of syngas. The objectives of this work are: To run a micropyrolyser in a rotary kiln reactor which was out of use for several years; To connect the micropyrolyser with a gas burner for determination of produced and exhaust gases; To run the pyrolyser in a continuous way for continuous production of syngas; To determine biomass mass flow and mass and energy balance of the system; To perform Proximate and Ultimate analyses of initial biomass and produced char and tar with a gas chromatographer to determine LHV of syngas. Two tests were performed during the course of this thesis work: A drying test of biomass and a pyrolysis test with a direct combustion of the produced syngas inside a gas burner. An analyzed sample of a gas mixture indicated a lower calorific value of 2,86 MJ/kg of the syngas due to the intake of a considerable amount of ambient air and unintentional leaks and loose-fitting seals. Theoretically, if an anaerobic environment could be achieved inside the micropyrolyser, the produced syngas would have the calorific value of 12,79 MJ/kg, a figure that can also be found in literature. To increase the calorific value of continuously produced gas in a micropyrolyser, the sealing system should be improved. The work was ...