Sequencing optimization and benefit analysis based on quality evaluation of SCR denitration catalyst
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摘要:
以某一燃煤电厂3层催化剂M2-N1-N2为实例，通过测试主要化学成分、比表面积、微量元素及脱硝率等指标，分析评判现有3层催化剂质量优劣，并优化3层催化剂的排序，确保NOx达标排放。结果表明：与SCR催化剂N1、N2相比，SCR催化剂M2中CaO、Al2O3等主要化学成分浓度小，参与烟气中SO3气体反应生成CaSO4和Al2(SO4)3的量较少，且不易在孔道中沉积，同时，烟气和飞灰中Na、Mg、Fe、K等微量元素在催化剂M2表面产生的积聚量少，占据有效酸性位点数量少。通过测试整体脱硝率及单层脱硝率、优化原排序三层催化剂的顺序，确保了新排序下整体脱硝率满足NOx排放要求，并从环境-经济-资源多维度进行效益分析，不同置换方法下的经济成本核算表明，新排序下SCR催化剂为该厂节省471.9万或330万元，节约了新鲜催化剂的制造资源，规避了催化剂在制造或处置过程中造成的环境污染环节，延长了催化剂使用寿命。
Abstract:Taking the three-layer catalyst M2-N1-N2 of a coal-fired power plant as an example, the indexes of main chemical composition, specific surface area, trace elements and denitration efficiency were tested, the quality of the existing three-layer catalyst was analyzed and evaluated, and the sequencing of the three-layer catalyst was optimized, to ensure NOx to meet the emission standard. The results showed that, compared with SCR catalyst N1/N2, SCR catalyst M2 had less chemical composition of CaO and Al2O3, which reacted with SO3 gas in the flue gas to generate less amount of CaSO4 and Al2(SO4)3, and it was not easy to deposit in the channel. At the same time, trace elements, such as Na, Mg, Fe and K, in the flue gas and fly ash accumulated less on the surface of catalyst M2 and occupied less effective acid sites. The overall denitration efficiency was tested, and the denitration efficiency of the single-layer SCR catalyst was also explored. The original sequencing three-layer catalyst was optimized to ensure the overall denitration efficiency to meet NOx emission requirements under the new sequencing. The benefit analysis was carried out from the multi-dimensions of environment, economy and resources. The economic cost accounting under different replacement methods showed that SCR catalyst under the new sequencing could save 4.719 million yuan or 3.3 million yuan for the plant. Moreover, it could save the manufacturing resources of the fresh SCR catalyst, and avoid the links of environmental pollution caused by the manufacture and handling of the SCR catalyst. SCR catalyst recycled would also prolong the life span of the catalyst.
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Key words:
- quality evaluation /
- sequencing optimization /
- ultra-low emission /
- benefit evaluation
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图 6 不同催化剂的主要化学成分浓度
Figure 6. Contents of main chemical components of different catalysts
图 8 不同NOx浓度下SCR催化剂的脱硝率
Figure 8. Denitration efficiency of SCR catalyst at different NOx concentrations
图 10 2种排序下SCR催化剂脱硝率对比分析
Figure 10. Comparative analysis of denitration efficiency of SCR catalysts under two sequencing conditions
表 1 整体脱硝率测试结果
Table 1. Three-layer catalyst series denitrification efficiency
位置 NOx浓度/(µL/L) 脱硝
率/%总脱硝
率/%设计脱硝
率/%入口 出口 上层(催化剂M2） 223.0 48.4 78.30 87.02 87.50 中层(催化剂N1） 48.4 36.4 24.79 下层(催化剂N2） 36.4 29.0 20.33 
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表 2 新排序SCR催化剂N2-N1-M2整体脱硝率
Table 2. Overal denitration efficiency of catalyst under a new sequence of three-layer N2-N1-M2
位置 NOx浓度/( µL/L) 脱硝
率/%总脱硝
率/%设计脱硝
率/%入口 出口 上层(催化剂N2) 224 82.2 63.30 88.66 87.50 中层(催化剂N1) 82.2 45.5 44.65 下层(催化剂M2) 45.5 25.4 44.18
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[1] 杜振, 王志东, 晏敏, 等.SCR脱硝催化剂实际运行性能分析[J]. 中国电力,2018,51(2):133-136.DU Z, WANG Z D, YAN M, et al. Analysis on actual operation performance of SCR denitration catalyst[J]. Electric Power,2018,51(2):133-136. [2] 李帅英, 武宝会, 姚皓, 等.SCR催化剂活性评估对NOx超低排放影响[J]. 中国电力,2017,50(8):163-167. doi: 10.11930/j.issn.1004-9649.2017.08.163.05LI S Y, WU B H, YAO H, et al. Effect of SCR catalyst activity evaluation on ultra low emission of NOx[J]. Electric Power,2017,50(8):163-167. doi: 10.11930/j.issn.1004-9649.2017.08.163.05 [3] 庄烨, 张东辉, 褚玥, 等.SCR脱硝在燃煤电厂超低排放中的适用性分析[J]. 环境工程学报,2017,11(7):4183-4189. doi: 10.12030/j.cjee.201606009ZHUANG Y, ZHANG D H, CHU Y, et al. Applicability analysis of SCR technology to ultra-low NOx emission for coal-fired power plants[J]. Chinese Journal of Environmental Engineering,2017,11(7):4183-4189. doi: 10.12030/j.cjee.201606009 [4] da SHANG, LI B K, LIU Z Q. Large eddy simulation of transient turbulent flow and mixing process in an SCR denitration system[J]. Chemical Engineering Research and Design,2019,141:279-289. doi: 10.1016/j.cherd.2018.11.006 [5] DAI Z J, WANG L L, TANG H, et al. Speciation analysis and leaching behaviors of selected trace elements in spent SCR catalyst[J]. Chemosphere,2018,207:440-448. doi: 10.1016/j.chemosphere.2018.05.119 [6] 宋玉宝, 王乐乐, 金理鹏, 等.基于现场性能测试的脱硝装置潜能评估及寿命预测[J]. 热力发电,2015,44(5):39-44. doi: 10.3969/j.issn.1002-3364.2015.05.039SONG Y B, WANG L L, JIN L P, et al. Potential evaluation and service life prediction for SCR device based on field performance test[J]. Thermal Power Generation,2015,44(5):39-44. doi: 10.3969/j.issn.1002-3364.2015.05.039 [7] 周卫青, 吴华成, 王斌, 等.燃煤电厂SCR催化剂活性跟踪检测及失活原因分析[J]. 华北电力技术,2015(8):23-27. doi: 10.16308/j.cnki.issn1003-9171.2015.08.007ZHOU W Q, WU H C, WANG B, et al. Tracking performance testing and deactivation analysis of the SCR catalyst for denitrification of coal-fired power plant[J]. North China Electric Power,2015(8):23-27. doi: 10.16308/j.cnki.issn1003-9171.2015.08.007 [8] LU C, WANG D, ZHU W T, et al. Performance evaluation and life management of SCR denitration catalyst[J]. IOP Conference Series Earth and Environmental Science,2020,495(1):012035. doi: 10.1088/1755-1315/495/1/012035 [9] 李德波, 廖永进, 陆继东, 等.燃煤电站SCR催化剂更换周期及策略优化数学模型[J]. 中国电力,2013,46(12):118-121. doi: 10.3969/j.issn.1004-9649.2013.12.024LI D B, LIAO Y J, LU J D, et al. Study on mathematical models for optimization of SCR catalyst replacement cycle and strategy[J]. Electric Power,2013,46(12):118-121. doi: 10.3969/j.issn.1004-9649.2013.12.024 [10] 李德波, 廖永进, 徐齐胜, 等.燃煤电站SCR脱硝催化剂更换策略研究[J]. 中国电力,2014,47(3):155-159. doi: 10.3969/j.issn.1004-9649.2014.03.031LI D B, LIAO Y J, XU Q S, et al. Study on SCR catalyst replacing strategy in coal-fired power plants[J]. Electric Power,2014,47(3):155-159. doi: 10.3969/j.issn.1004-9649.2014.03.031 [11] HAO L F, XING D S, CAO R L. The environment influences evaluation on SCR flue-gas[J]. Applied Mechanics and Materials, 2011, 71/72/73/74/75/76/77/78: 3156-3159. [12] CHEN L, LIAO Y F, XIN S R, et al. Simultaneous removal of NO and volatile organic compounds (VOCs) by Ce/Mo doping-modified selective catalytic reduction (SCR) catalysts in denitrification zone of coal-fired flue gas[J]. Fuel,2020,262:116485. doi: 10.1016/j.fuel.2019.116485 [13] 谢新华, 陆继东, 黄秋雄, 等.火电厂SCR催化剂更新策略分析及效益评估[J]. 华中科技大学学报(自然科学版),2016,44(1):118-121. doi: 10.13245/j.hust.160124XIE X H, LU J D, HUANG Q X, et al. Benefit evaluation of replacement strategies for SCR catalyst in thermal power plants[J]. Journal of Huazhong University of Science and Technology (Natural Science Edition),2016,44(1):118-121. doi: 10.13245/j.hust.160124 [14] 晏敏, 杜振, 宋小宁, 等.SCR脱硝催化剂主要化学成分的检测解析[J]. 环境工程,2019,37(6):22-25. doi: 10.13205/j.hjgc.201906005YAN M, DU Z, SONG X N, et al. Analysis on detection of main chemical compositions of SCR denitrification catalysts[J]. Environmental Engineering,2019,37(6):22-25. doi: 10.13205/j.hjgc.201906005 [15] 云端, 邓斯理, 宋蔷.V2O5 -WO3/TiO2系SCR催化剂的钾中毒及再生方法[J]. 环境科学研究,2009,22(6):730-735.YUN D, DENG L S, SONG Q, et al. Potassium deactivation and regeneration method of V2O5-WO3/TiO2 SCR catalyst[J]. Research of Environmental Sciences,2009,22(6):730-735. [16] 李德波, 廖永进, 徐齐胜, 等.我国SCR脱硝催化剂服役过程中运行规律的研究[J]. 动力工程学报,2014,34(10):808-813.LI D B, LIAO Y J, XU Q S, et al. Experimental study on running condition of the catalyst in a domestic SCR denitrification system[J]. Journal of Chinese Society of Power Engineering,2014,34(10):808-813. [17] 张广才, 李锐攀, 朱学智, 等 超超临界锅炉及SCR参数精细化控制实现NOx浓度实时达标的优化与应用[J]. 环境工程技术学报, 2018, 8(6): 586-592.ZHANG G C, LI R P, ZHU X Z, et al. Optimization and application of accurate control of ultra-supercritical boiler and SCR parameters for NOx real time value up to the standard[J]. Journal of Environmental Engineering Technology, 2018, 8(6): 586-592. [18] 束航, 张玉华, 范红梅, 等.SCR脱硝中催化剂表面NH4HSO4生成及分解的原位红外研究[J]. 化工学报,2015,66(11):4460-4468.SHU H, ZHANG Y H, FAN H M, et al. FT-IR study of formation and decomposition of ammonium bisulfates on surface of SCR catalyst for nitrogen removal[J]. CIESC Journal,2015,66(11):4460-4468. [19] 胡志健, 安璐, 李永光.焦化厂SCR脱硝催化剂积碳失活研究[J]. 环境工程技术学报,2020,10(2):192-196. doi: 10.12153/j.issn.1674-991X.20190112HU Z J, AN L, LI Y G. Study on coking deactivation of SCR denitration catalyst in a coke-oven plant[J]. Journal of Environmental Engineering Technology,2020,10(2):192-196. doi: 10.12153/j.issn.1674-991X.20190112 [20] 平立. 太仓电厂脱硝催化剂再生项目效益分析[D]. 北京: 华北电力大学, 2015. -
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