本文主要研究内容
作者丁凯（2019）在《赤泥基SCR催化剂脱硝性能的优化研究》一文中研究指出：氮氧化物(NOx)是我国主要大气污染物之一,对生态环境和人体健康均造成了严重威胁。国家最新“十三五”发展规划明确提出了 2020年NOx排放量较2015年降低115%的约束性指标。面对巨大的环保压力和严苛的排放指标,脱硝性能优异的NH3-SCR技术(Selective catalytic reduction of NO with NH3)仍是我国燃煤电厂采用的主流NOx控制技术。目前广泛采用的钒钛类SCR催化剂存在成本偏高、脱硝温度窗口较窄、钒存在生物毒性易造成二次污染等诸多问题,其应用前景受到限制,开发廉价、高效、宽温度窗口、环保的新型SCR催化剂来替代传统钒钛类催化剂已势在必行。赤泥作为工业生产氧化铝排出的污染性废渣,其资源化利用成为亟待解决的世界性难题。研究表明拜耳法赤泥具有应用于SCR领域的巨大潜力,如能实现其在SCR领域的应用,则既实现了对赤泥的资源化利用,又能以低廉的成本实现对氮氧化物的脱除。本研究以山东铝业拜耳法赤泥为原料,在预活化处理的基础上,分别负载四种助剂对其进行优化改性处理,实验确定最优改性助剂Ce及最佳Ce负载量,揭示Ce对赤泥催化剂脱硝性能的优化改性机理;探究煅烧温度、超声处理等制备工艺对铈改性赤泥催化剂脱硝特性的影响规律,并揭示其影响机理;探讨运行参数对催化剂脱硝活性的影响规律,并推荐合适的工业运行参数。经开发得到了一种廉价、高效、宽温度窗口的SCR脱硝催化剂。主要得出以下结论:(1)本研究选取的山东铝业拜耳法赤泥具备在SCR脱硝领域研究应用的潜力,但原始赤泥的脱硝活性较低,需进行改性活化处理。酸洗+锻烧是原始赤泥有效预活化手段,酸洗+煅烧处理显著降低了赤泥中对催化活性起抑制作用的碱金属含量;疏通了赤泥表面的孔道结构,增强了孔间连通性,细化了颗粒尺寸,增大了孔容积和比表面积,有利于NH3-SCR反应的进行。酸洗后煅烧得到的ARM催化剂在中高温段的脱硝活性大幅提升,取得了最高63.38%的NO转化率,较原始赤泥的最高10.13%的转化率提升显著;在所采用实验条件下,硝酸是酸洗活化最合适的酸种类。(2)在预活化处理的基础上,分别考察了负载Zr、Cr、Cu和Ce助剂对赤泥脱硝活性的影响规律,结果表明,Ce具有最佳的优化改性效果。Ce的负载显著降低了α-Fe203的结晶度;疏通了赤泥表面的空隙结构,增加了催化剂的孔容量和比表面积,降低了 SCR过程中的传质阻力;催化剂的表面酸性位尤其是弱酸酸性位的含量大幅提高,能够为SCR反应提供更多的活性反应位点。Ce的最佳负载量为10%,10%Ce/ARM催化剂最高脱硝效率达到100%,起活温度T50较ARM降低了近138℃,脱硝活性区间为248.4～407.8℃。(3)煅烧温度对催化剂脱硝性能影响显著,随着煅烧温度提高,催化剂的脱硝温度窗口整体向高温方向偏移。其中500℃煅烧催化剂具有最宽广的脱硝活性区间,因而选取500℃为最佳煅烧温度。煅烧温度过低时,催化剂过高的表面氧浓度导致NH3氧化为NO的副反应加剧,使催化剂的脱硝温度窗口变窄,煅烧温度过高时,催化剂孔道结构开始恶化,传质阻力增大,不利于SCR反应进行。(4)超声处理改善了催化剂的中低温脱硝活性,使催化剂的温度窗口向中低温方向拓展,其中30min超声处理得到的催化剂具有最宽的脱硝活性区间(237.4～402.8℃),其脱硝温度窗口能够满足目前“深度调峰”背景下燃煤电厂SCR脱硝机组的运行要求;表征结果表明:超声处理起到了细化晶粒、提高比表面积和孔容量的作用;运行工况对催化剂脱硝特性的研究表明:赤泥型催化剂推荐O2浓度为3%,NH3/NO比为1,催化剂具有良好的O2暂态响应特性和NH3吸附特性。
Abstract
dan yang hua wu (NOx)shi wo guo zhu yao da qi wu ran wu zhi yi ,dui sheng tai huan jing he ren ti jian kang jun zao cheng le yan chong wei xie 。guo jia zui xin “shi san wu ”fa zhan gui hua ming que di chu le 2020nian NOxpai fang liang jiao 2015nian jiang di 115%de yao shu xing zhi biao 。mian dui ju da de huan bao ya li he yan ke de pai fang zhi biao ,tuo xiao xing neng you yi de NH3-SCRji shu (Selective catalytic reduction of NO with NH3)reng shi wo guo ran mei dian an cai yong de zhu liu NOxkong zhi ji shu 。mu qian an fan cai yong de fan tai lei SCRcui hua ji cun zai cheng ben pian gao 、tuo xiao wen du chuang kou jiao zhai 、fan cun zai sheng wu du xing yi zao cheng er ci wu ran deng zhu duo wen ti ,ji ying yong qian jing shou dao xian zhi ,kai fa lian jia 、gao xiao 、kuan wen du chuang kou 、huan bao de xin xing SCRcui hua ji lai ti dai chuan tong fan tai lei cui hua ji yi shi zai bi hang 。chi ni zuo wei gong ye sheng chan yang hua lv pai chu de wu ran xing fei zha ,ji zi yuan hua li yong cheng wei ji dai jie jue de shi jie xing nan ti 。yan jiu biao ming bai er fa chi ni ju you ying yong yu SCRling yu de ju da qian li ,ru neng shi xian ji zai SCRling yu de ying yong ,ze ji shi xian le dui chi ni de zi yuan hua li yong ,you neng yi di lian de cheng ben shi xian dui dan yang hua wu de tuo chu 。ben yan jiu yi shan dong lv ye bai er fa chi ni wei yuan liao ,zai yu huo hua chu li de ji chu shang ,fen bie fu zai si chong zhu ji dui ji jin hang you hua gai xing chu li ,shi yan que ding zui you gai xing zhu ji Ceji zui jia Cefu zai liang ,jie shi Cedui chi ni cui hua ji tuo xiao xing neng de you hua gai xing ji li ;tan jiu duan shao wen du 、chao sheng chu li deng zhi bei gong yi dui shi gai xing chi ni cui hua ji tuo xiao te xing de ying xiang gui lv ,bing jie shi ji ying xiang ji li ;tan tao yun hang can shu dui cui hua ji tuo xiao huo xing de ying xiang gui lv ,bing tui jian ge kuo de gong ye yun hang can shu 。jing kai fa de dao le yi chong lian jia 、gao xiao 、kuan wen du chuang kou de SCRtuo xiao cui hua ji 。zhu yao de chu yi xia jie lun :(1)ben yan jiu shua qu de shan dong lv ye bai er fa chi ni ju bei zai SCRtuo xiao ling yu yan jiu ying yong de qian li ,dan yuan shi chi ni de tuo xiao huo xing jiao di ,xu jin hang gai xing huo hua chu li 。suan xi +duan shao shi yuan shi chi ni you xiao yu huo hua shou duan ,suan xi +duan shao chu li xian zhe jiang di le chi ni zhong dui cui hua huo xing qi yi zhi zuo yong de jian jin shu han liang ;shu tong le chi ni biao mian de kong dao jie gou ,zeng jiang le kong jian lian tong xing ,xi hua le ke li che cun ,zeng da le kong rong ji he bi biao mian ji ,you li yu NH3-SCRfan ying de jin hang 。suan xi hou duan shao de dao de ARMcui hua ji zai zhong gao wen duan de tuo xiao huo xing da fu di sheng ,qu de le zui gao 63.38%de NOzhuai hua lv ,jiao yuan shi chi ni de zui gao 10.13%de zhuai hua lv di sheng xian zhe ;zai suo cai yong shi yan tiao jian xia ,xiao suan shi suan xi huo hua zui ge kuo de suan chong lei 。(2)zai yu huo hua chu li de ji chu shang ,fen bie kao cha le fu zai Zr、Cr、Cuhe Cezhu ji dui chi ni tuo xiao huo xing de ying xiang gui lv ,jie guo biao ming ,Ceju you zui jia de you hua gai xing xiao guo 。Cede fu zai xian zhe jiang di le α-Fe203de jie jing du ;shu tong le chi ni biao mian de kong xi jie gou ,zeng jia le cui hua ji de kong rong liang he bi biao mian ji ,jiang di le SCRguo cheng zhong de chuan zhi zu li ;cui hua ji de biao mian suan xing wei you ji shi ruo suan suan xing wei de han liang da fu di gao ,neng gou wei SCRfan ying di gong geng duo de huo xing fan ying wei dian 。Cede zui jia fu zai liang wei 10%,10%Ce/ARMcui hua ji zui gao tuo xiao xiao lv da dao 100%,qi huo wen du T50jiao ARMjiang di le jin 138℃,tuo xiao huo xing ou jian wei 248.4～407.8℃。(3)duan shao wen du dui cui hua ji tuo xiao xing neng ying xiang xian zhe ,sui zhao duan shao wen du di gao ,cui hua ji de tuo xiao wen du chuang kou zheng ti xiang gao wen fang xiang pian yi 。ji zhong 500℃duan shao cui hua ji ju you zui kuan an de tuo xiao huo xing ou jian ,yin er shua qu 500℃wei zui jia duan shao wen du 。duan shao wen du guo di shi ,cui hua ji guo gao de biao mian yang nong du dao zhi NH3yang hua wei NOde fu fan ying jia ju ,shi cui hua ji de tuo xiao wen du chuang kou bian zhai ,duan shao wen du guo gao shi ,cui hua ji kong dao jie gou kai shi e hua ,chuan zhi zu li zeng da ,bu li yu SCRfan ying jin hang 。(4)chao sheng chu li gai shan le cui hua ji de zhong di wen tuo xiao huo xing ,shi cui hua ji de wen du chuang kou xiang zhong di wen fang xiang ta zhan ,ji zhong 30minchao sheng chu li de dao de cui hua ji ju you zui kuan de tuo xiao huo xing ou jian (237.4～402.8℃),ji tuo xiao wen du chuang kou neng gou man zu mu qian “shen du diao feng ”bei jing xia ran mei dian an SCRtuo xiao ji zu de yun hang yao qiu ;biao zheng jie guo biao ming :chao sheng chu li qi dao le xi hua jing li 、di gao bi biao mian ji he kong rong liang de zuo yong ;yun hang gong kuang dui cui hua ji tuo xiao te xing de yan jiu biao ming :chi ni xing cui hua ji tui jian O2nong du wei 3%,NH3/NObi wei 1,cui hua ji ju you liang hao de O2zan tai xiang ying te xing he NH3xi fu te xing 。
论文参考文献
论文详细介绍
论文作者分别是来自山东大学的丁凯，发表于刊物山东大学2019-07-16论文，是一篇关于催化剂论文,赤泥论文,改性活化论文,超声论文,山东大学2019-07-16论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自山东大学2019-07-16论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：催化剂论文; 赤泥论文; 改性活化论文; 超声论文; 山东大学2019-07-16论文;