Using rice husk as raw material and FeCl3 as catalyst, the basic elements and combustion characteristics of rice husk hydrothermal char were studied by elemental analyzer and thermogravimetric method. The effects of hydrothermal temperature and catalyst concentration on the elemental structure and combustion characteristics of rice husk hydrothermal char were investigated. The results show as follows： 1） With the increase of hydrothermal temperature, the fixed carbon content and calorific value of hydrothermal carbon increase, while the atomic ratios of O/C and H/C decrease gradually. The addition of FeCl3 further deepens the degree of carbonization of hydrothermal carbon, but the effect of hydrothermal temperature on the degree of carbonization is greater than the concentration of FeCl3. 2） When no FeCl3 was added, the hydrothermal carbon combustion shows double peaks, and the peak value of volatiles is significantly higher than that of fixed carbon combustion. With the increase of hydrothermal temperature, the peak value of volatile combustion decreases and the peak value of fixed carbon combustion increases. After the addition of FeCl3, the combustion range of fixed carbon expands, and the double peaks gradually melt into a single peak, and the whole transferrs to the high temperature region. 3） When the hydrothermal temperature is constant, with the increase of catalyst concentration, the DTG curve of hydrothermal carbon combustion changes from double peaks to single peak, and the overall transfers to the low temperature region. 4） As the heating rate increases, the ignition temperature and burnout temperature of samples increase, and the hydrothermal carbon combustion shifts to the high temperature region. 5） When the hydrothermal temperature is constant, the ignition temperature and burnout temperature advance slightly after the addition of FeCl3, and composite combustion characteristic index SN increases first and then decreases. FeCl3 improves the energy quality and combustion quality of hydrothermal char, and provides theoretical basis for the application of FeCl3 in biomass thermal conversion in the future.
Key words
biomass /
hydrothermal carbonization /
chemical structure /
combustion characteristic /
composite combustion characteristic index
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References
[1] 张蓓蓓. 我国生物质原料资源及能源潜力评估[D]. 北京: 中国农业大学, 2018.
ZHANG B B.Biomass raw material resources and energy potential assessment in China[D]. Beijing: China Agricultural University, 2018.
[2] HETLAND, YOWARGANA P, LEDUC S, et al.Carbon-negative emissions: systemic impacts of biomass conversion: a case study on CO2 capture and storage option[J]. International journal of greenhouse gas control, 2016, 4(9): 330-342.
[3] DIZA M C, UGUNA C N, FLORENTINO L, et al.Evaluation of hydrochars from lignin hydrous pyrolysis to produce biocokes after carbonization[J]. Journal of analytical and applied pyrolysis, 2017, 12(4): 742-751.
[4] ZHAN L, JIANG L, ZHANG Y L, et al.Reduction, detoxification and recycling of solid waste by hydrothermal technology: a review[J]. Chemical engineering journal, 2020, 3(5):1246-1271.
[5] MOHAMED B A, ELLIS N, KIM C S, et al.Synergistic effects of catalyst mixtures on biomass catalytic pyrolysis[J]. Frontiers in bioengineering and biotechnology, 2020, 8(1): 615-650.
[6] QI R Z, XU G H, ZHOU Y, et al.Clean solid fuel produced from cotton textiles waste through hydrothermal carbonization with FeCl3: upgrading the fuel quality and combustion characteristics[J]. Energy, 2020, 24(1): 118-135.
[7] 张晓娟. 典型废弃生物质水热碳化提质制备多功能生物炭研究[D]. 大连: 大连理工大学, 2019.
ZHANG X J.Preparation of multifunctional biochar from typical waste biomass by hydrothermal carbonization[D]. Dalian: Dalian University of Technology, 2019.
[8] 康秦豪. 生物质水热降解制备糠醛和纤维素的实验研究[D]. 北京: 北京化工大学, 2019.
KANG Q H.Experimental study on hydrothermal degradation of biomass to furfural and cellulose[D]. Beijing: Beijing University of Chemical Technology, 2019.
[9] 周亚运. 预处理生物质的热解试验研究[D]. 南京: 东南大学, 2015.
ZHOU Y Y, XIAO J, LYU X, et al.Experimental study on pyrolysis of pretreated biomass[D]. Nanjing: Southeast University, 2015.
[10] XU Z H, ZHOU Y W, SUN Z H, et al.Understanding reactions and pore-forming mechanisms between waste cotton woven and FeCl3 during the synthesis of magnetic activated carbon[J]. Chemosphere, 2020, 24(1): 1251-1273.
[11] KONG L Z, LI G M, WANG H, et al.Hydrothermal catalytic conversion of biomass for lactic acid production[J]. Journal of chemical technology and biotechnology, 2007, 83(3): 383-388.
[12] YU J Z, WU Z S, AN X F, et al.Trace metal elements mediated co-pyrolysis of biomass and bentonite for the synthesis of biochar with high stability[J]. Science of the total environment, 2021, 7(4): 145-181.
[13] PU G W, ZHU W L, ZHOU H P, et al.Co-combustion characteristics of inferior coal and biomass blends in an oxygen-enriched atmosphere[J]. Bioresources, 2015, 10(1): 1452-1461.
[14] YANG J, HE Q, YANG L X.A review on hydrothermal co-liquefaction of biomass[J]. Applied energy, 2019, 2(1): 926-945.
[15] SAHA N, REZA M T.Effect of pyrolysis on basic functional groups of hydrochars[J]. Biomass conversion and biorefinery, 2019, 11(3): 1117-1124.
[16] 唐尚媛. 木质纤维生物质酸碱催化水热预处理及酶解的研究[D]. 北京: 北京交通大学, 2019.
TANG S Y.Study on acid-base catalytic hydrothermal pretreatment and enzymatic hydrolysis of lignocellulosic biomass[D]. Beijing: Beijing Jiaotong University, 2019.
[17] LIU S Q, NIU Y Q, WEN L P, et al.Effects of physical structure of high heating-rate chars on combustion characteristics[J]. Fuel, 2020, 2(6): 117059.
[18] 郭淑青, 董向元, 马敏阳, 等. K元素迁移对谷子秆水热碳化特性的影响[J]. 太阳能学报, 2021, 42(6): 482-486.
GUO S Q, DONG X Y, MA M Y, et al.Effect of K element migration on hydrothermal carbonization characteristics of millet stalks[J]. Acta energiae solaris sinica, 2021, 42(6): 482-486.
[19] YANG W, WANG H, ZHANG M, et al.Fuel properties and combustion kinetics of hydrochar prepared by hydrothermal carbonization of bamboo[J]. Bioresource technology, 2016, 2(5): 199-204.
[20] 曹运齐. 园林废弃物水热转化制备水热炭及燃料前体研究[D]. 西安: 陕西科技大学, 2021.
CAO Y Q.Preparation of hydrothermal carbon and fuel precursors by hydrothermal conversion of garden waste[D]. Xi’an: Shaanxi University of Science and Technology, 2021.
[21] LANG Q Q, ZHANG B, LIU Z G, et al.Co-hydrothermal carbonization of corn stalk and swine manure: combustion behavior of hydrochar by thermogravimetric analysis[J]. Bioresource technology, 2018, 27(1): 75-83.
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