Abstract
Pyrolysis of food waste using microwave irradiation was carried out in this study to produce quality biochar for heating applications. Optimum conditions for microwave-assisted pyrolysis of food waste particles were determined using response surface methodology (RSM). Combined effects of the operating variables, namely pyrolysis temperature (°C), residence time (min) and nitrogen flow rate (mL min−1), were analyzed by conducting 20 experiments. Microwave-assisted pyrolysis results were correlated by applying RSM with the regressions coefficients of 92.90% for biochar and 90.305% for fixed carbon content. Microwave power of 450 W yielded 60.03 wt. % of biochar with a fixed carbon content of 48.71 wt. % under the optimum pyrolysis conditions of 400 °C temperature, 30 min residence time and 50 mL min−1 of nitrogen flow rate. The higher heating value of the biochar was 33.35 MJ kg−1.
Acknowledgements
The first author gratefully acknowledges the National Institute of Technology, Karnataka Surathkal, for the financial support to purchase the microwave reactor under the annual plan fund [No. 233/NITK/CHE/APF/2014-15/A9 dated 23-02-2015].
Disclosure statement
No potential conflict of interest was reported by the authors.