旱伞草水热炭的稳定性特征及固碳潜能  

Stability and carbon sequestration potential of hydrochar derived from Cyperus alternifolius

作　　者：王雨婷 陈冠益[1,2,3] 李磊 崔孝强 WANG Yuting;CHEN Guanyi;LI Lei;CUI Xiaoqiang(School of Environmental Science and Engineering,Tianjin University,Tianjin 300372,China;School of Mechanical Engineering,Tianjin University of Commerce,Tianjin 300134,China;School of Science,Tibet University,Lhasa 850012,China)

机构地区：[1]天津大学环境科学与工程学院,天津300372 [2]天津商业大学机械工程学院,天津300134 [3]西藏大学理学院,拉萨850012

出　　处：《农业环境科学学报》2022年第3期639-647,共9页Journal of Agro-Environment Science

基　　金：国家重点研发计划项目(2019YFC1903905)。

摘　　要：为探究湿地植物旱伞草水热炭的稳定性特征与固碳潜能,分别在200、220、240℃和260℃下制备旱伞草水热炭,通过元素分析、红外光谱分析、X射线衍射分析、热重分析及化学氧化分析等方法分别探究了水热炭的理化性质及热稳定性和化学稳定性,并对不同温度水热炭的固碳潜能进行评估。结果表明:随着水热碳化温度升高,水热炭产率下降,pH值和灰分含量上升,H/C和O/C降低,-OH、-C-O等不稳定含氧官能团减少,芳香化程度增加。热重分析和稳定性系数(R_(50))分析结果表明,不同温度制备的水热炭的R_(50)值为0.47~0.59。H_(2)O_(2)氧化试验表明,中低温(220℃)制备的水热炭的抗氧化性能最好,其氧化后稳定碳含量为54.14%。此外,固碳潜能分析结果表明,随着碳化温度的升高,旱伞草水热炭的固碳系数在30.21%~31.54%范围内波动,长期固碳潜能的CO2当量为2.76~2.88 Mt·a^(-1)。研究表明:200℃和220℃制备的中低温水热炭具有较好的化学稳定性,且在短期固碳效果上具有优势;而260℃制备的高温水热炭具有最佳的热稳定性和长期固碳潜能,在固碳减排方面具有良好的应用前景。To explore the stability and carbon sequestration potential of hydrochar from wetland plants, hydrochars were prepared from Cyperus alternifolius L.(CA)at 200, 220, 240 ℃, and 260 ℃. Elemental analysis, Fourier transform infrared spectroscopy(FTIR), X-ray Diffraction(XRD), Thermogravimetric analysis(TG), and chemical oxidation were employed to explore the physicochemical properties and thermal and chemical stability of hydrochar and to further evaluate the carbon sequestration potential of hydrochar at different temperatures. The results showed that as the hydrothermal carbonization temperature increased, the yield of hydrochar decreased, the pH value and ash content increased, the H/C and O/C ratios decreased, the labile oxygen-containing functional groups such as —OH and—C—O decreased, and the aromatization degree increased. The results of the Thermogravimetric analysis and stability coefficient(R_(50))showed that the R_(50) value of hydrochars prepared at different temperatures ranged from 0.47 to 0.59. The H_(2)O_(2) oxidation trial showed that the hydrochar prepared at a medium-low temperature of 220 ℃ had the best oxidation resistance, with a stable carbon content of 54.14%after oxidation. In addition, the analysis results of the carbon sequestration potential showed that with increased carbonization temperature, the carbon sequestration coefficient of the hydrochar derived from CA fluctuated in the range of 30.21%~31.54%, and the CO2 equivalent of the long-term carbon sequestration potential ranged from 2.76 Mt·a^(-1)to 2.88 Mt·a^(-1). The study showed that the medium-low temperature hydrochars prepared at 200 ℃ and 220 ℃ had good chemical stability and advantages in the short-term carbon sequestration effect,whereas the high-temperature hydrochar prepared at 260 ℃ had the best thermal stability and long-term carbon sequestration potential,and good prospects for carbon sequestration and emission reduction.

关 键 词：旱伞草 水热炭 稳定性 固碳 

分 类 号：X173[环境科学与工程—环境科学]