Mass conversion pathway during anaerobic digestion of wheat straw

Jian Gao; Juan Li; Akiber Chufo Wachemo; Hairong Yuan; Xiaoyu Zuo; Xiujin Li

doi:10.1039/d0ra02441d

Mass conversion pathway during anaerobic digestion of wheat straw

RSC Adv. 2020 Jul 23;10(46):27720-27727. doi: 10.1039/d0ra02441d. eCollection 2020 Jul 21.

Authors

Jian Gao¹, Juan Li², Akiber Chufo Wachemo^{1

3}, Hairong Yuan¹, Xiaoyu Zuo¹, Xiujin Li¹

Affiliations

¹ Department of Environmental Science and Engineering, Beijing University of Chemical Technology 15 Beisanhuan East Road, Chaoyang District Beijing 100029 PR China zuoxy@mail.buct.edu.cn xjli@mail.buct.edu.cn.
² Beijing Municipal Ecological and Environmental Monitoring Center 14 Chegongzhuang West Road, Haidian District Beijing 100048 PR China.
³ Department of Water Supply and Environmental Engineering, Arba Minch University P.O. Box 21 Arba Minch Ethiopia.

Abstract

A material flow analysis (MFA) method was employed to investigate elemental flow direction during the anaerobic digestion (AD) of wheat straw (WS) pretreated with potassium hydroxide. A lab-scale batch AD experiment conducted at 35 ± 1 °C was investigated to realize carbon conversion in biogas, liquid and solid digestates. The results showed that the highest growth rate of carbon conversion in biogas was observed from the fourth day to the twenty-fourth day, which accounted for 70.64%. The cumulative biogas production of WS was 531 mL g^-1 VS, along with a high volatile solids degradation rate (55.0%). The MFA results indicated that the flow mass fractions of carbon in biogas, liquid and solid digestates were 49.96%, 5.61% and 44.43%, respectively. The flow mass fraction of nitrogen in liquid and solid digestates was 45.65% and 54.35%, respectively. This study can provide a theoretical basis for elemental flow in each product from biogas projects.