Optimisation of Microwave Pretreatment for Biogas Enhancement through Anaerobic Digestion of Microalgal Biomass

  • RuiZhe Feng College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, Heilongjiang Province, China
  • Asad A. Zaidi College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, Heilongjiang Province, China
  • Kun Zhang College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, Heilongjiang Province, China
  • Yue Shi College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, Heilongjiang Province, China

Abstract

In this study, optimization of microwave (MW) pretreatment conditions for anaerobic digestion of green microalgae (Enteromorpha) is carried out by using response surface methodology (RSM). MW power, pretreatment time and liquid-solid ratio were selected as independent variables for optimization. The optimum conditions were achieved at MW power, pretreatment time and liquid-solid ratio of 656.92 W, 5.10 min and 33.63:1, respectively. From these optimum conditions, it was found that MW pretreatment power of about 600 W had better effect. An anaerobic digestion was carried out batch-wise with working volume, operating temperature and mixing rate as 250 ml, 37 °C and 150 rpm, respectively. Optimum conditions provide highest amount of COD and reducing sugar increase of 10,420 mg/L and 0.77-0.79 g/L respectively. The increase in COD and reducing sugar showed that the pretreatment has improved anaerobic digestion of microalgae. The peak biogas production amount of MW pretreated 20:1, 6 min group reached 244 mL whereas the control group only reached 188 mL in total.

Keywords: anaerobic digestion, biofuel, biomass, microwave (MW) pretretament, response surface methodology
Published online
2018-06-15
How to Cite
Feng, R., Zaidi, A. A., Zhang, K. and Shi, Y. (2019) “Optimisation of Microwave Pretreatment for Biogas Enhancement through Anaerobic Digestion of Microalgal Biomass”, Periodica Polytechnica Chemical Engineering, 63(1), pp. 65-72. doi: https://doi.org/10.3311/PPch.12334.
Section
Articles