Improving production of volatile fatty acids and hydrogen from microalgae and rice residue: Effects of physicochemical characteristics and mix ratios
메타 데이터
바이오화학분류
바이오정밀화학
연료
논문
Improving production of volatile fatty acids and hydrogen from microalgae and rice residue: Effects of physicochemical characteristics and mix ratios
학술지
Applied energy
저자명
Sun, Chihe; Xia, Ao; Liao, Qiang; Fu, Qian; Huang, Yun; Zhu, Xun; Wei, Pengfei; Lin, Richen; Murphy, Jerry D.
초록
<P><B>Abstract</B></P> <P>Dark fermentation may be hindered by insufficient bioavailable carbon and nitrogen sources as well as recalcitrant cell wall structures of substrates. Protein-rich microalgae and carbohydrate-rich rice residue with various mix ratios can optimise biohydrogen and volatile fatty acids production. Optimal pretreatment of the microalgae with 1% H<SUB>2</SUB>SO<SUB>4</SUB> and the rice residue with 0.5% H<SUB>2</SUB>SO<SUB>4</SUB> under hydrothermal heating (140 °C, 10 min) achieved reducing sugar yields of 187.3 mg/g volatile solids (VS) (hydrolysis efficiency: 54%) and 924.9 mg/g VS (hydrolysis efficiency: 100%), respectively. Multiscale physiochemical characterisations of solid hydrolytic residues confirmed considerable damage to both substrates. Co-fermentation of pretreated rice residue and microalgae at a mix ratio of 5:1 exhibited the maximum hydrogen yield of 201.8 mL/g VS, a 10.7-fold increase compared to mono-fermentation of pretreated microalgae. The mix ratio of 25:1 resulted in the highest carbon to volatile fatty acids conversion (96.8%), corresponding to a maximum energy conversion efficiency of 90.8%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Mixed biomass of rice residue and microalgae was used as co-fermentation substrate. </LI> <LI> Physiochemical characteristics of solid hydrolytic residues were analysed. </LI> <LI> Hydrolysis efficiency of polysaccharide in rice residue was 100%. </LI> <LI> The highest H<SUB>2</SUB> yield of 201.8 mL/g VS was achieved at a mix ratio of 5:1. </LI> <LI> Energy and carbon conversion efficiencies reached up to 90.8% and 96.8%. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>