Bibliographic Details
| Title: |
Fe−Co/Al2O3 多孔介质催化剂催化低浓度瓦斯燃烧特性. |
| Alternate Title: |
Catalytic combustion properties of Fe−Co/Al2O3 porous media catalysts for low-concentration coal mine ga. |
| Authors: |
韩家章1 hanjz@163.com, 曹运齐1,2, 肜浩楠2, 翟 成3, 李点尚1, 童校长1, 刘 方2 fang.liu@cumt.edu.cn |
| Source: |
Coal Science & Technology (0253-2336). Jun2026, Vol. 54 Issue 6, p183-195. 13p. |
| Subject Terms: |
*Catalytic oxidation, *Catalysts, *Flame stability, *Methane, *Coalbed methane, *Lean combustion, *Abatement (Atmospheric chemistry) |
| Abstract (English): |
Addressing the low utilization and massive venting of low-concentration methane (LCM) in coal mines (< 8%), which results in energy waste and greenhouse effect. Fe−Co/Al2O3bimetallic porous media catalyst loaded with Fe2O3 and Co3O4 as dual active components was prepared using ultrasonic-assisted impregnation method to investigate the combustion performance of LCM. The effects of excess air ratio φa and flow rate f on combustion characteristics were examined, and long-term combustion stability was tested. The results indicated that the Fe and Co in Fe−Co/Al2O3synergistically engaged in CH4 catalytic reaction. Fe3+ and Co3+ were partially reduced to Fe2+ and Co2+ species, and the formation of CoFe2O4 spinel structure improved thermal stability and resistance to sintering of the catalyst, enabling it to maintain good catalytic activity during high-temperature lean combustion. CH4 oxidation reaction followed the MvK mechanism, in which lattice oxygen participated in the cleavage and activation of the C—H bond in CH4, with its consumption forming oxygen vacancies. Adsorbed oxygen dynamically replenished lattice oxygen to maintain the migration and cycling of oxygen species, while further promoting the oxidation of intermediates. Excess air ratio and flow rate significantly influenced temperature distribution and flame migration, low excess air ratio or low flow rate tended to cause combustion flashback, whereas high excess ratio or high flow rate could lead to the risk of blow off. The thermal buffering effect generated by the gradient pore structure of the porous media, combined with the sustained heat release of the catalytic reaction, alleviated temperature fluctuation and enhanced flame stability. Within the range of φa = 2.44—2.56 and f = 50—65 L/min, the flame was anchored in the middle of the burner, the combustion temperature was maintained above 800 ℃, and NOx emissions were extremely low. At φa = 2.56, the preheating zone temperature remained around 220 ℃ even after 72 h of combustion, and the CH4 conversion approached 100% throughout the process, confirming that the coupling of gradient porous media and catalytic reaction significantly improved lean-burn performance and stability. This study provides a novel insights and technical support for the clean and efficient utilization of coal mine LCM. [ABSTRACT FROM AUTHOR] |
| Abstract (Chinese): |
针对 8% 以下煤矿低浓度瓦斯利用率低与大量排空造成能源浪费和温室效应问题, 采用超声 辅助浸渍法制备了负载 Fe2 O 3与 Co3O4 双活性组分的 Fe−Co/Al2 O 3双金属多孔介质催化剂, 在渐变孔 密度燃烧器中开展低浓度甲烷催化燃烧性能研究, 重点考察了过量空气系数 φ a 和流量 f 对燃烧特性 的影响, 并测试了长期燃烧稳定性。结果表明: Fe−Co/Al2 O 3中的 Fe、Co 双金属协同参与了 CH4 催 化反应, Fe3+和 Co3+在反应中被部分还原为 Fe2+和 Co2+物种, CoFe2 O 4尖晶石结构的形成提高了催化 剂的热稳定性和抗烧结能力, 使其在高温贫燃过程中保持良好的催化活性。CH4 氧化反应遵循 MvK 机制, 晶格氧参与 CH4中 C — H 键断裂与活化, 其消耗形成氧空位; 吸附氧动态补充晶格氧, 在维 持氧物种迁移与循环的同时进一步促进中间产物氧化。过量空气系数和流量显著影响温度分布与火 焰迁移, 低过量空气系数或低流量易引发燃烧回火, 高过量空气系数或高流量则会导致脱火风险; 多孔介质渐变孔结构的热缓冲作用与催化反应的持续放热减缓了温度波动并提高了火焰稳定性。在 φ a = 2.44 ～ 2.56 与 f = 50 ～ 65 L /min, 火焰锚定于燃烧器中游, 燃烧温度维持在 800 ℃ 以上, 且 NOx 排放极低。在 φ a = 2.56 下, 燃烧持续 72 h 预热区温度仍保持在 220 ℃ 左右, CH4 转化率接近 100%, 表明渐变多孔介质与催化反应的耦合显著提高了贫燃特性和稳定性。本研究为煤矿低浓度瓦 斯的清洁高效利用提供了新的思路和技术支撑。 [ABSTRACT FROM AUTHOR] |
| Database: |
Energy & Power Source |
