Enhancing volatile fatty acid (VFA) and bio-methane production from lawn grass with pretreatment.
The bioconversion of fiber-based carbohydrates during anaerobic digestion (AD) is impeded due to the recalcitrant nature of the plant cell wall. Pretreatment of lignocellulose materials under mild conditions are needed to improve the digestibility at minimum cost. This study investigated the effects of different pretreatments, including ozone, soaking aqueous ammonia (SAA), combined ozone and SAA (OSAA), and size reduction to enhance volatile fatty acid (VFA) and bio-methane production when lawn grass was used as substrate. To study VFA production, methanogenesis was selectively inhibited by sodium 2-bromoethanesulfonate to decouple the relation between VFA and bio-methane. The enzymatic hydrolysis of SAA (residence time 24h at 50°C) and OSAA (10 min ozonation and 6h of SAA) in pretreatment of lawn grass sample resulted in 86.71% and 89.63% sugar recovery, respectively. The specific methane yields of the control, ozone, SAA, OSAA, and size-reduced grass samples were 402.5, 358.8, 481.0, 462.6, and 358.3 ml CH4/g volatile solid (VS), respectively.
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
Liang
L
Yu
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
Mahesh
M
Bule
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
Jingwei
J
Ma
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
Quanbao
Q
Zhao
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
Craig
C
Frear
Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA. Electronic address: chens@wsu.edu.
Shulin
S
Chen
D019342:Acetic Acid / Q000378:metabolism; D056804:Biofuels; D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000096:biosynthesis; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D008697:Methane / Q000096:biosynthesis*; D006109:Poaceae / Q000378:metabolism*; D011422:Propionates / Q000378:metabolism; D014835:Volatilization; D014866:Waste Products
D056804:Biofuels; D002241:Carbohydrates; D005232:Fatty Acids, Volatile; D011422:Propionates; D014866:Waste Products; C029658:propionic acid; D008697:Methane; D019342:Acetic Acid
Anaerobic digestion; Bio-methane; Pretreatment; Volatile fatty acid (VFA)