Energy and exergy analysis of rice husk high-temperature pyrolysis. (14th December 2016)

• Record Type: Journal Article
• Authors: Wang, Xinyu; Lv, Wei; Guo, Li; Zhai, Ming; Dong, Peng; Qi, Guoli
• Is Part Of: International journal of hydrogen energy. Volume 41:Number 46(2016)
• Page Start: 21121
• Page End: 21130
• Publication Date: 2016-12-14
• Subjects: Rice husk -- High-temperature pyrolysis -- Exergy analysis -- Energy analysis; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2016.09.155
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Based on a two-stage fixed bed high-temperature pyrolysis system, the influence of temperature (800–1200 °C) on total energy and exergy, as well as exergy and energy efficiency of unreacted carbon, tar and pyrolysis gas were analyzed. The results indicate energy and exergy of each component in the pyrolysis gas as well as the total energy and exergy increase with temperature. Energy value and exergy value contributions of the components in the pyrolysis gas at 800 °C and 900 °C are CO > CH4 > H2 > CO2 . From 1000 °C to 1200 °C, the rank turns into CH4 > CO > H2 > CO2 . The energy efficiency and exergy efficiency of pyrolysis gas are in the range of 64.57–72.68% and 52.93–60.64%, respectively. The increasing rate of energy value and exergy value of the pyrolysis gas reaches maximum at 1000 °C. The energy efficiency and exergy efficiency of unreacted carbon and tar decrease with temperature. The consumption of energy for tar collection and loss of energy and exergy carried by tar can be reduced by increasing temperature. The loss exergy efficiency increases slightly below 900 °C and decreases from 38.8% to 34.6% above 900 °C. Highlights: Energy and exergy of rice husk pyrolysis in a two-stage fixed bed are analyzed. Energy and exergy contributions of each component in the pyrolysis gas are obtained. Energy and exergy efficiency of pyrolysis gas are 64.57–72.68% and 52.93–60.64%, respectively. Energy and exergy efficiency of fixed carbon and tar decrease with temperature. The highest irreversibility efficiency occurs at 900 °C.