林德海1,
马少丹1,
马静1,
孙琦1,
李永龙1,
徐文强1,
王宝冬1
1.北京低碳清洁能源研究所，北京 102211
基金项目: 神华集团重大项目（ST930015SH07）
北京低碳清洁能源研究所科技项目（CF9300172231）
Deactivation mechanism and regeneration of SCR catalyst used in 600 MW unit of coal fired power plant
MA Ziran1,,LIN Dehai1,
MA Shaodan1,
MA Jing1,
SUN Qi1,
LI Yonglong1,
XU Wenqiang1,
WANG Baodong1
1.National Institute of Clean-and-Low-Carbon Energy, Beijing 102211, China
-->
摘要
HTML全文
图
参考文献
相关文章
施引文献
资源附件
访问统计
摘要:针对燃用中国典型煤的2×600 MW机组电厂失活的蜂窝式催化剂，使用XRF、ICP、物理吸附仪、吡啶吸附、H2-TPR等表征手段等对催化剂失效前后的理化性质进行表征，研究了催化剂的失效原因。结果表明，催化剂的失活是由于碱金属Na、K和碱土金属CaO等物质导致了催化剂的物理失效以及化学中毒。催化剂物理失效是由于催化剂表面碱金属颗粒的沉积造成催化剂孔道堵塞，致使活性中心被覆盖。催化剂的化学中毒是由于酸性位丧失和活性位VOx氧化还原性质降低，进而导致NH3的吸附过程，以及催化剂表面吸附态NH3和NOx物种的活化过程均受到了抑制。利用项目组开发的1 000 m3·a-1再生装置，对失效催化剂进行了中试再生，结果表明，表面和孔道内积累的中毒物质全部被去除，催化剂孔结构、酸性位数量和活性位状态均恢复至新鲜催化剂水平。实验室活性评价结果显示，再生催化剂脱硝效率相比失效催化剂在360 °C提高到85%左右，与新鲜催化剂相当。再生催化剂组装为2层测试模块（每层模块含9根催化剂），历经神华四川能源公司江油电厂侧线反应器5 000 h实际烟气测试，脱硝性能良好，维持在88%左右，超过初始设计值80%，且NH3逃逸和SO2/SO3转化率满足电厂工程要求。
关键词: 脱硝催化剂/
失效机理/
再生/
中试/
实际烟气测试
Abstract:Deactivation mechanism of commercial V2O5-WO3/TiO2 catalyst for a 2×600 MW power plant has been studied on a basis of X-ray fluorescence(XRF), inductive coupled plasma emission spectrometer(ICP), BET and pore structure analysis, diffuse reflectance infrared fourier transformed spectroscopy of pyridine adsorption and H2 temperature-programmed reduction experiments. Both the decrease of the specific surface area and the masking of V2O5 active sites were caused by alkali and alkaline-earth metals deposition, which could be attributed to mechanical deactivation. Besides, they both coordinated to the hydroxyl groups and active sites on catalyst surface, leading to the decreased amount of acid sites and the reducibility of active sites. After the catalysts were poisoned, the activity was significantly suppressed due to the inhibited adsorption and activation process for reactants. The regeneration on an own-developed 1 000 m3·a-1 pilot device led to the reversible improvement of surface acid sites and active oxygen species. The activity of the regenerated SCR catalyst was close to fresh catalyst with a NO conversion of 85% at 360 oC. 5 000 h slip-stream flue gas test in Shenhua Sichuan Energy Jiangyou Power Plant has also been applied to validate the catalytic performance, with NOx conversion remaining stable at about 88% and no excess NH3 slip and SO2/SO3 conversion.
Key words:SCR catalyst/
deactivation mechanism/
regeneration/
pilot scale/
actual flue gas test.
| [1] | 王宝冬,汪国高,刘斌,等. 选择性催化还原脱硝催化剂的失活,失效预防,再生和回收利用研究进展[J]. 化工进展,2013,32(S1):133-139 |
| [2] | 中华人民共和国国家标准.火电厂大气污染物排放标准:GB 13223-2011 [S].北京:中国环境科学出版社，2011 |
| [3] | YU Y K,HE C,CHEN J S, et al.Deactivation mechanism of de-NOx catalyst (V2O5-WO3/TiO2) used in coal fired power plant[J].Journal of Fuel Chemistry and Technology, 2012,40(11):1359-1365 10.1016/S1872-5813(13)60003-1 |
| [4] | PENG Y,LI J H,SI W Z,et al.Insight into deactivation of commercial SCR catalyst by arsenic: An experiment and DFT study[J].Environmental Science & Technology, 2014,48(23):13895-13900 10.1021/es503486w |
| [5] | 白向飞,李文华,陈亚飞,等. 中国煤中微量元素分布基本特征[J]. 煤质技术,2007(1):1-4. |
| [6] | KLING ?,ANDERSSON C,MYRINGER ?,et al.Alkali deactivation of high-dust SCR catalysts used for NOx reduction exposed to flue gas from 100 MW-scale biofuel and peat fired boilers:Influence of flue gas composition[J].Applied Catalysis B:Environmental,2007,69(3):240-251 10.1016/j.apcatb.2006.03.022 |
| [7] | ZHENG Y J,JENSEN A D,JOHNSSON J E,et al.Deactivation of V2O5-WO3-TiO2 SCR catalyst at biomass fired power plants: Elucidation of mechanisms by lab-and pilot-scale experiments[J].Applied Catalysis B:Environmental,2008,83(3):186-194 10.1016/j.apcatb.2008.02.019 |
| [8] | PENG Y,LI J H,SI W Z,et al.Deactivation and regeneration of a commercial SCR catalyst: Comparison with alkali metals and arsenic[J].Applied Catalysis B:Environmental,2015,168-169:195–202 10.1016/j.apcatb.2014.12.005 |
| [9] | ZHENG Y J,JENSEN A D,JOHNSSON J E.Laboratory investigation of selective catalytic reduction catalysts: Deactivation by potassium compounds and catalyst regeneration[J].Industrial & Engineering Chemical Research,2004,43:941-947 10.1021/ie030404a |
| [10] | LI M,LIU B,WANG X R,et al.A promising approach to recover a spent SCR catalyst: Deactivation by arsenic and alkaline metals and catalyst regeneration[J].Chemical Engineering Journal,2018,342:1-8 10.1016/j.cej.2017.12.132 |
| [11] | LI X S,LIU C D,LI X,et al.A neutral and coordination regeneration method of Ca-poisoned V2O5-WO3/TiO2 SCR catalyst[J].Catalysis Communication,2017,100:112-116 10.1016/j.catcom.2017.06.034 |
| [12] | BUSCA G,LARRUBIA M A,ARRIGHI L,et al.Catalytic abatement of NOx: Chemical and mechanistic aspects[J].Catalysis Today,2005,107:139-148 10.1016/j.cattod.2005.07.077 |
| [13] | FORZATTI P.Present status and perspectives in de-NOx SCR catalysis[J].Applied Catalysis A:General,2001,222(1):221-236 10.1016/S0926-860X(01)00832-8 |
| [14] | SCHWIDDER M,KUMAR M S,BENTRUP U,et al.The role of Br?nsted acidity in the SCR of NO over Fe-MFI catalysts[J].Microporous and Mesoporous Materials,2008,111(1):124-133 10.1016/j.micromeso.2007.07.019 |
| [15] | EMEIS C A.Determination of integrated molar extinction coefficients for infrared absorption bands of pyridine adsorbed on solid acid catalysts[J].Journal of Catalysis,1993,141(2):347-354 10.1006/jcat.1993.1145. |
| [16] | WANG X Q,SHI A J,DUAN Y F,et al.Catalytic performance and hydrothermal durability of CeO2–V2O5–ZrO2/WO3–TiO2 based NH3-SCR catalysts[J].Catalysis Science & Technology,2012,2(7):1386-1395 10.1039/C2CY20140B |
| [17] | CHEN L,LI J H,GE M F.Promotional effect of Ce-doped V2O5-WO3/TiO2 with low vanadium loadings for selective catalytic reduction of NOx by NH3[J].Journal of Physical Chemistry C,2009,113(50):21177-21184 10.1021/jp907109e |
| [18] | YU W C,WU X D,SI Z C,et al.Influences of impregnation procedure on the SCR activity and alkali resistance of V2O5–WO3/TiO2 catalyst[J].Applied Surface Science,2013,283:209-214 10.1016/j.apsusc.2013.06.083 |
| [19] | MA Z R,WENG D,WU X D,et al.Effects of WOx modification on the activity, adsorption and redox properties of CeO2 catalyst for NOx reduction with ammonia[J].Journal of Environmental Sciences,2012,24(7):1305-1316 10.1016/S1001-0742(11)60925-X |
| [20] | MA Z R,WU X D,FENG Y,et al.Low-temperature SCR activity and SO2 deactivation mechanism of Ce-modified V2O5–WO3/TiO2 catalyst[J].Progress in Natural Science: Materials International,2015,25(4):342-352 10.1016/j.pnsc.2015.07.002 |
| [21] | REDDY B M,KHAN A,YAMADA Y,et al.Structural characterization of CeO2?TiO2 and V2O5/CeO2?TiO2 catalysts by Raman and XPS techniques[J].Journal of Physical Chemistry B,2003,107 (22):5162–5167 10.1021/jp0344601 |
| [22] | SHAN W P,LIU F D,HE H,et al.A superior Ce-W-Ti mixed oxide catalyst for the selective catalytic reduction of NOx with NH3[J].Applied Catalysis B:Environmental,2012,115-116:100-106 10.1016/j.apcatb.2011.12.019 |
| [23] | CHANG H Z,LI J H,SU W K,et al.A novel mechanism for poisoning of metal oxide SCR catalysts: Base–acid explanation correlated with redox properties[J].Chemical Communications,2014,50(70):10031-10034 10.1039/c4cc02991g |
| [24] | MA Z R,WU X D,H?relind H, et al.NH3-SCR reaction mechanisms of NbOx/Ce0.75Zr0.25O2 catalyst: DRIFTS and kinetics studies[J].Journal of Molecular Catalysis A:Chemical,2016,423:172-180 10.1016/j.molcata.2016.06.023 |
Turn off MathJax -->
点击查看大图计量
文章访问数:1486
HTML全文浏览数:1025
PDF下载数:454
施引文献:0
出版历程
刊出日期:2018-06-18
-->
600 MW机组脱硝催化剂失活机理及中试再生
马子然1,,林德海1,
马少丹1,
马静1,
孙琦1,
李永龙1,
徐文强1,
王宝冬1
1.北京低碳清洁能源研究所，北京 102211
基金项目: 神华集团重大项目（ST930015SH07） 北京低碳清洁能源研究所科技项目（CF9300172231）
关键词: 脱硝催化剂/
失效机理/
再生/
中试/
实际烟气测试
摘要:针对燃用中国典型煤的2×600 MW机组电厂失活的蜂窝式催化剂，使用XRF、ICP、物理吸附仪、吡啶吸附、H2-TPR等表征手段等对催化剂失效前后的理化性质进行表征，研究了催化剂的失效原因。结果表明，催化剂的失活是由于碱金属Na、K和碱土金属CaO等物质导致了催化剂的物理失效以及化学中毒。催化剂物理失效是由于催化剂表面碱金属颗粒的沉积造成催化剂孔道堵塞，致使活性中心被覆盖。催化剂的化学中毒是由于酸性位丧失和活性位VOx氧化还原性质降低，进而导致NH3的吸附过程，以及催化剂表面吸附态NH3和NOx物种的活化过程均受到了抑制。利用项目组开发的1 000 m3·a-1再生装置，对失效催化剂进行了中试再生，结果表明，表面和孔道内积累的中毒物质全部被去除，催化剂孔结构、酸性位数量和活性位状态均恢复至新鲜催化剂水平。实验室活性评价结果显示，再生催化剂脱硝效率相比失效催化剂在360 °C提高到85%左右，与新鲜催化剂相当。再生催化剂组装为2层测试模块（每层模块含9根催化剂），历经神华四川能源公司江油电厂侧线反应器5 000 h实际烟气测试，脱硝性能良好，维持在88%左右，超过初始设计值80%，且NH3逃逸和SO2/SO3转化率满足电厂工程要求。
English Abstract
Deactivation mechanism and regeneration of SCR catalyst used in 600 MW unit of coal fired power plant
MA Ziran1,,LIN Dehai1,
MA Shaodan1,
MA Jing1,
SUN Qi1,
LI Yonglong1,
XU Wenqiang1,
WANG Baodong1
1.National Institute of Clean-and-Low-Carbon Energy, Beijing 102211, China
Keywords: SCR catalyst/
deactivation mechanism/
regeneration/
pilot scale/
actual flue gas test
Abstract:Deactivation mechanism of commercial V2O5-WO3/TiO2 catalyst for a 2×600 MW power plant has been studied on a basis of X-ray fluorescence(XRF), inductive coupled plasma emission spectrometer(ICP), BET and pore structure analysis, diffuse reflectance infrared fourier transformed spectroscopy of pyridine adsorption and H2 temperature-programmed reduction experiments. Both the decrease of the specific surface area and the masking of V2O5 active sites were caused by alkali and alkaline-earth metals deposition, which could be attributed to mechanical deactivation. Besides, they both coordinated to the hydroxyl groups and active sites on catalyst surface, leading to the decreased amount of acid sites and the reducibility of active sites. After the catalysts were poisoned, the activity was significantly suppressed due to the inhibited adsorption and activation process for reactants. The regeneration on an own-developed 1 000 m3·a-1 pilot device led to the reversible improvement of surface acid sites and active oxygen species. The activity of the regenerated SCR catalyst was close to fresh catalyst with a NO conversion of 85% at 360 oC. 5 000 h slip-stream flue gas test in Shenhua Sichuan Energy Jiangyou Power Plant has also been applied to validate the catalytic performance, with NOx conversion remaining stable at about 88% and no excess NH3 slip and SO2/SO3 conversion.
