Biomethane Yield, Physicochemical Structures, and Microbial Community Characteristics of Corn Stover Pretreated by Urea Combined with Mild Temperature Hydrotherm
Abstract
:1. Introduction
2. Material and Methods
2.1. Feedstock and Inoculum
2.2. Experimental Design
2.2.1. Pretreatment Methods
2.2.2. Anaerobic Digestion
2.2.3. Analytical Methods
2.2.4. Data Analysis
3. Results and Discussion
3.1. AD Performance
3.1.1. Biomethane Production
3.1.2. Biomethane Yield
3.1.3. Substance Bioconversion
3.2. Pretreatment Mechanism
3.2.1. Total Volatile Fatty Acids (TVFAs)
3.2.2. Scanning Electron Microscope (SEM)
3.2.3. X-ray Diffractometer (XRD)
3.2.4. Fourier-Transform Infrared Spectroscopy (FTIR)
3.3. Microbial Community Analyses
3.3.1. Diversity and Richness
3.3.2. Bacterial Composition
3.3.3. Archaeal composition
3.3.4. Correlation between Microbial Community and Environmental Characteristics
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Nomenclature
CS | corn stover |
AD | anaerobic digestion |
TS | total solid |
TC | total carbon |
TN | total nitrogen |
TH | total hydrogen |
TO | total oxygen |
VS | total volatile solid |
MLSS | mixed liquid suspended solids |
DMP | daily methane production |
TVFAs | total volatile fatty acids |
BD | biodegradability |
SEM | scanning electron microscope |
XRD | X-ray Diffractometer |
FTIR | fourier transform infrared spectroscopy |
CrI | crystallinity index |
RDA | redundancy analysis |
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Group | Pretreatment Time | I002 a | Iam b | CrI (%) |
---|---|---|---|---|
Untreated | 0 h | 32,933.3 | 17,608.3 | 46.5 |
T24 | 24 h | 34,575 | 17,950 | 48.1 |
T48 | 48 h | 32,783.3 | 16,958.3 | 48.3 |
T72 | 72 h | 35,650 | 18,275 | 48.7 |
T96 | 96 h | 35,075 | 19,408.3 | 44.7 |
Peak Position (cm−1) | Functional Groups |
---|---|
898 | β-(1,4)-glycosidic bond (C-O-C) |
1052 | ether bond in hemicellulose (C-O-C) |
1160, 1248 | C-O stretching of COOH and C-O vibration of guaiacyl ring |
1430, 1515 | aromatic skeleton vibration |
1732 | carbonyl group on ester bond between hemicellulose and lignin (C=O) |
2919 | -CH3, -CH2, -CH in aliphatic compounds |
3420 | Intermolecular and intramolecular hydrogen bond (-OH) |
Group | Richness | Diversity | Coverage | ||||
---|---|---|---|---|---|---|---|
Sobs | Ace | Chao | Shannon | Simpson | |||
Bacteria | T24 | 384 | 476.47 | 511.66 | 3.54 | 0.07 | 0.99 |
T48 | 436 | 535.10 | 545.02 | 3.75 | 0.06 | 0.99 | |
T72 | 467 | 566.79 | 544.68 | 4.05 | 0.043 | 0.99 | |
T96 | 455 | 538.08 | 532.34 | 3.87 | 0.06 | 0.99 | |
Untreated | 329 | 417.63 | 404.62 | 2.65 | 0.27 | 0.99 | |
Archaea | T24 | 24 | 27.47 | 26 | 1.45 | 0.35 | 0.99 |
T48 | 20 | 21.74 | 20 | 1.66 | 0.25 | 0.99 | |
T72 | 25 | 27.65 | 26.5 | 1.62 | 0.26 | 0.99 | |
T96 | 21 | 21.75 | 21 | 1.56 | 0.33 | 0.99 | |
Untreated | 25 | 25.96 | 25.33 | 1.86 | 0.22 | 0.99 |
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Lu, Y.; Yuan, H.; Zuo, X.; Chang, Y.; Li, X. Biomethane Yield, Physicochemical Structures, and Microbial Community Characteristics of Corn Stover Pretreated by Urea Combined with Mild Temperature Hydrotherm. Polymers 2021, 13, 2207. https://doi.org/10.3390/polym13132207
Lu Y, Yuan H, Zuo X, Chang Y, Li X. Biomethane Yield, Physicochemical Structures, and Microbial Community Characteristics of Corn Stover Pretreated by Urea Combined with Mild Temperature Hydrotherm. Polymers. 2021; 13(13):2207. https://doi.org/10.3390/polym13132207
Chicago/Turabian StyleLu, Yao, Hairong Yuan, Xiaoyu Zuo, Yanqing Chang, and Xiujin Li. 2021. "Biomethane Yield, Physicochemical Structures, and Microbial Community Characteristics of Corn Stover Pretreated by Urea Combined with Mild Temperature Hydrotherm" Polymers 13, no. 13: 2207. https://doi.org/10.3390/polym13132207