Coupling effect of Fe-based catalyst on coal pyrolysis-combustion NOx control
YANG Song1,2, KONG Xiang-lu2,3, WANG Qi2,3, LI Jiang-peng2,3, JIAO Ting-ting2,3, ZHANG Kai-xia2,3, LIU Shou-jun1,2,3, SHANG Guan-Ju2,3
1. College of Chemical Engineering and Technology, Taiyuan University of Technology, Taiyuan 030024, China; 2. Shanxi Civil Clean Fuel Engineering Research Center, Taiyuan 030024, China; 3. State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan 030024, China
Abstract：In order to solve the problem of NOx emission in civil loose-burning raw coal, a source control strategy of "pyrolysis to reduce nitrogen and couple combustion to denitrate" was put forward to realize pollutant emission. The additive was introduced into raw coal in one step to control NOx emission in the process of pyrolysis and combustion. The specific research contents were as follows:coal and iron additive were pyrolyzed in a tube furnace to prepare clean fuel, The emission of NOx during clean fuel combustion was studied. The influence of iron additives on nitrogen migration and the influence of surface structure and pore structure of clean coke were systematically investigated. The results showed that iron additives loaded before pyrolysis existed stably in coke and promoted the transformation of nitrogen-containing compounds into N2 during pyrolysis. In the combustion process of clean coke, the existence of iron additives is beneficial to the catalytic reduction of NOx by C and CO, and then the emission of NOx in the combustion process is controlled. The iron additives introduced in one step play a coupling effect of NOx control in the coal pyrolysis-combustion process, realizing the ultra-low emission of NOx.
李霞,王磊,任泉,等.乌鲁木齐市大气污染治理成效的综合评估分析[J]. 中国环境科学, 2016,36(1):307-313. Li X, Wang L, Ren Q, et al. Evaluation and analysis on the effects of air pollution control in Urumqi[J]. China Environmental Science, 2016,36(1):307-313.
[2]
李朋,吴华成,周卫青,等.京津冀"以电代煤"替代大气污染物排放清单[J]. 中国环境科学, 2021,41(4):1489-1497. Li P, Wu C H, Zhou W Q, et al. Emission inventory of atmospheric pollutants replaced by "coal-to-electricity" policy in Beijing-Tianjin-Hebei region.[J]. China Environmental Science, 2021,41(4):1489-1497.
[3]
Hou J, Ma Y, Li S, et al. Transformation of sulfur and nitrogen during Shenmu coal pyrolysis[J]. Fuel, 2018,231(1):134-144.
[4]
谢建军,杨学民,朱文魁,等.煤炭解耦燃烧过程N迁移与转化Ⅰ:热解阶段煤N的释放规律[J]. 燃料化学学报, 2012,40(8):919-926. Xie J J, Yang X M, Zhu W K, et al. Nitrogen transformation during coal decoulping combustion I:release behavior of coal-nitrogen during pyrolysis stage[J]. Journal of Fuel Chemistry and Technology, 2012, 40(8):919-926.
[5]
Chen P, Wang D, Gu M, et al. The Effect Mechanism of Fe on coal pyrolysis to NOx precursors:Quantum chemical calculations and mass spectrometry experiments[J]. ACS Omega, 2020,5(36):23247-23256.
[6]
Amin M N, Li Y, Razzaq R, et al. Pyrolysis of low rank coal by nickel based zeolite catalysts in the two-staged bed reactor[J]. Journal of Analytical and Applied Pyrolysis, 2016,118:54-62.
[7]
Tsubouchi N, Ohtsuka Y. Nitrogen chemistry in coal pyrolysis:Catalytic roles of metal cations in secondary reactions of volatile nitrogen and char nitrogen[J]. Fuel Processing Technology, 2008, 89(4):379-390.
[8]
Zhang X, Wu H, Xie M, et al. A thorough theoretical exploration of the effect mechanism of Fe on HCN heterogeneous formation from nitrogen-containing char[J]. Fuel, 2020,280:118662.
[9]
Naoto T, Yasuo O. Nitrogen chemistry in coal pyrolysis:Catalytic roles of metal cations in secondary reactions of volatile nitrogen and char nitrogen[J]. Fuel Processing Technology, 2008,89(4):379-390.
[10]
Yi L, Liu H, Lu G, et al. Effect of Mixed Fe/Ca Additives on Nitrogen Transformation during Protein and Amino Acid Pyrolysis[J]. Energy & Fuels, 2017,31(9):9484-9490.
[11]
Naoto T, Yusuke M, Yuuki M, et al. Coprocessing of Pyrolytic Nitrogen Removal of Low-Rank Coals and Reduction of Limonite Ore[J]. Energy & Fuels, 2017,31(4):3885-3891.
[12]
Zhang H, Liu J, Shen J, et al. Thermodynamic and kinetic evaluation of the reaction between NO (nitric oxide) and char(N) (char bound nitrogen) in coal combustion[J]. Energy, 2015,82:312-321.
[13]
韩奎华,齐建荟,李辉,等.木醋调质石灰石用于O2/CO2燃煤同时脱硫脱硝性能[J]. 燃料化学学报, 2013,41(11):1378-1383. Han K H, Qi J H, Li H, et al. Performance of simultaneous desulfurization and denitration using limestone modified by wood vinegar in O2/CO2 coal combustion[J]. Journal of Fuel Chemistry and Technology, 2013,41(11):1378-1383.
[14]
马腾坤,房晶瑞,孙勇,等.TiO2载体掺杂对Mn-Ce/TiO2催化剂低温脱硝性能影响研究[J]. 燃料化学学报, 2017,45(4):491-496. Ma T K, Fang J R, Sun Y, et al. Study on the modification effect of TiO2 support on the low temperature denitration activity of Mn-Ce/TiO2 catalysts[J]. Journal of Fuel Chemistry and Technology, 2017,45(4):491-496.
[15]
胡强,熊志波,白鹏,等.铈钛掺杂促进铁氧化物低温SCR脱硝性能的机理[J]. 中国环境科学, 2016,36(8):2304-2310. Hu Q, Xiong Z B, Bai P, et al. Promotional mechanism of cerium oxide and titanium oxide doping on the low-temperature NH3-SCR activity of iron oxide[J]. China Environmental Science, 2016,36(8):2304-2310.
[16]
Gong Z, Wenfei W, Zhao Z, et al. Combination of catalytic combustion and catalytic denitration on semi-coke with Fe2O3 and CeO2[J]. Catalysis Today, 2018,318:59-65.
[17]
Lei Z, Yan J, Fang J, et al. Catalytic combustion of coke and NO reduction in-situ under the action of Fe, Fe-CaO and Fe-CeO2[J]. Energy, 2021,216:119246.
[18]
Gradoń B, Lasek J. Investigations of the reduction of NO to N2 by reaction with Fe[J]. Fuel, 2010,89(11):3505-3509.
[19]
Jin S, Bingtao Z, Yaxin S. Advanced control of NO emission from algal biomass combustion using loaded iron-based additives[J]. Energy, 2019,185.
[20]
张信莉,路春美,王栋,等.滴定方法对Fe0.7Mn0.3Oz催化剂低温SCR脱硝性能的影响[J]. 燃烧科学与技术, 2015,21(5):471-477. Zhang X L, Lu C M, Wang W D, et al. Influence of titration methods on low-temperature SCR performance of Fe0.7Mn0.3Oz Catalysts[J]. Journal of Combustion Science and Technology, 2015,21(5):471-477.
[21]
鞠付栋,陈汉平,杨海平,等.不同变质煤热解和气化中燃料氮的转化规律[J]. 煤炭转化, 2011,34(3):21-26. Ju F D, Chen H P, Yang H P, et al. Fuel-nitrogen evolution of different rank coal during pyrolysis and gasification[J]. Coal Conversion, 2011,34(3):21-26.
[22]
邹涛,张勇,贺根良,等.神府煤热解中试过程中硫、氮迁移分布探讨[J]. 煤化工, 2015,(6):21-25. Zhou T, Zhang Y, He G L, et al. Discussion on migration and distribution of sulfur and nitrogen based on pyrolysis pilot test of Shenfu coals[J]. Coal Chemical Industry, 2015,(6):21-25.
[23]
侯建材,曲旋,张荣,等.固体热载体热解煤中氮的迁移特性[J]. 煤炭转化, 2016,39(2):81-85. Hou J C, Qu X, Zhang R, et al. Transformation of nitrogen during coal pyrolysis with solid heat carrier[J]. Coal Conversion, 2016,39(2):81-85.
[24]
景旭亮,王志青,房倚天.流化床气化炉半焦细粉水蒸气再气化特性及动力学研究[J]. 燃料化学学报, 2013,41(4):400-406. Jing X L, Wang Z Q, Fang Y T, et al. Steam re-gasification properties and kinetics of coal char fines derived from fluidized bed gasifier[J]. Journal of Fuel Chemistry and Technology, 2013,41(4):400-406.
[25]
李朋,吴华成,周卫青,等.民用燃煤不同燃烧阶段细颗粒物排放特征[J]. 中国环境科学, 2020,40(11):4652-4659. Li P, Wu H C, Zhou W Q, et al. Emission characteristic of fine particulate matter at different combustion phases of residential coal[J]. China Environmental Science, 2020,40(11):4652-4659.
[26]
熊志波,金晶,路春美,等.铁基催化剂的微波水热处理对其SCR脱硝性能的影响[J]. 中国环境科学, 2014,34(7):1785-1789. Xiong Z B, Jin J, Lu C M, et al. Effect of microwave hydrothermal treatment for iron-based catalyst on its selective catalytic reduction of NO with NH3[J]. China Environmental Science, 2014,34(7):1785-1789.
[27]
杨利超,罗慧娟,张凯,等.天然褐铁矿添加剂对无烟煤燃烧及NOx排放的影响[J]. 煤炭学报, 2019,44(S01):8. Yang L C, Luo H J, Zhang K, et al. Effect of limonite additive on combustion and NOx emission characteristics of anthracite[J]. Journal of China Coal Society, 2019,44(S01):8.
[28]
张光学,周安琪,范海燕,等.铁铈氧化物催化剂脱硝性能及抗碱金属盐中毒性能研究[J]. 热力发电, 2016,45(1):37-41. Zhang G X, Zhou A Q, Fan H Y, et al. Performance of Fe-Ce oxide denitration catalyst and its resistance to toxicity[J]. Thermal Power Generation, 2016,45(1):37-41.
[29]
陈丽丽,刘守军,杨颂,等.炭基燃料燃烧利用过程中NOx释放控制技术进展[J]. 应用化工, 2018,47(10):2279-2286. Chen L L, Liu S J, Yang S, et al. Technical progress of the control of NOx emission in carbon based fuel combustion process[J]. Applied Chemical Industry, 2018,47(10):2279-2286.
[30]
阎志中,张凯霞,刘月华,等.铁助剂对长焰煤"热解-燃烧"过程中的减氮脱硝作用研究[J]. 煤炭学报, 2021,46(4):9. Yan Z Z, Zhang K X, Liu Y H, et al. Effect of iron additives on nitrogen reduction and denitrification of long-flame coal during pyrolysis and combustion[J]. Journal of China Coal Society, 2021,46(4):9.
[31]
刘月华,上官炬,刘守军,等.铁镍复合助剂对煤热解过程中氮迁移规律的影响[J]. 化工进展, 2021,40(1):164-172. Liu Y H, Shangguan J, Liu S J, et al. Nitrogen migration regarding the addition of iron-Ni composite additives during coal pyrolysis[J]. Chemical Industry and Engineering Progress, 2021,40(1):164-172.
[32]
Qi X J, Song W W, Liu L, et al. Effect of iron on Shenfu coal char structure and its influence on gasification reactivity[J]. Journal of Analytical & Applied Pyrolysis, 2014,110:401-407.
[33]
Liu Y, Guan Y, Zhang K, et al. Toward understanding the reactivity and catalytic mechanism of coal pyrolysis with metal chloride modification[J]. Journal of Analytical and Applied pyrolysis, 2019, 138:196-202.
[34]
Liang D, Xie Q, Wei Z, et al. Transformation of alkali and alkaline earth metals in Zhundong coal during pyrolysis in an entrained flow bed reactor[J]. Journal of Analytical & Applied Pyrolysis, 2019,142:104661.
[35]
Lu Q X, Zhang N, Yang Q, et al. Influence of calcium promoter on catalytic pyrolysis characteristics of iron-loaded brown coal in a fixed bed reactor-ScienceDirect[J]. Journal of the Energy Institute, 2020, 93(2):695-710.
