高校化学工程学报
高校化學工程學報
고교화학공정학보
JOURNAL OF CHEMICAL ENGINEERING OF CHINESE UNIVERSITIES
2013年
6期
1058-1063
,共6页
陈万苗%刘庆航%杨昌涛%瞿赞%杨士建%谢江坤%晏乃强
陳萬苗%劉慶航%楊昌濤%瞿讚%楊士建%謝江坤%晏迺彊
진만묘%류경항%양창도%구찬%양사건%사강곤%안내강
逃逸氨%选择性还原脱硝(SCR)%Cu系催化剂%Ru%催化氧化
逃逸氨%選擇性還原脫硝(SCR)%Cu繫催化劑%Ru%催化氧化
도일안%선택성환원탈초(SCR)%Cu계최화제%Ru%최화양화
slip ammonia%selective catalytic reduction (NH3-SCR)%Cu modified catalysts%Ru%selective catalytic oxidation
为减少烟气氨法选择性还原催化脱硝(NH3-SCR)过程氨的逃逸问题,提出了在SCR催化单元尾部增设对氨具有高效分解作用的改性SCR催化剂的方法。分别考察了Cu及Ru等金属元素对W/V/Ti型SCR催化剂的改性效果。结果表明,Cu、Ru 两种金属元素改性后的催化剂对逃逸氨均有较好的脱硝还原效果及强化氨的催化分解作用。对氨分解产物分析表明,Cu改性催化剂对氨的分解产物中NOx转化率较高,而Ru改性SCR催化剂不仅具有非常高的氨催化氧化活性,同时其分解产物对N2的选择性能够达到90%以上。另外,考察了温度、催化剂预硫化处理、NO等因素对逃逸氨的分解作用的影响,催化剂在300~400℃具有最好的活性,预硫化对氨的分解作用具有抑制作用,尤其对Cu系催化剂。Ru/SCR催化剂具有很好的抗硫性能,经过预硫化处理后,在NO存在的条件下,NH3去除率能够达到80%以上,在逃逸氨控制方面具有应用前景。
為減少煙氣氨法選擇性還原催化脫硝(NH3-SCR)過程氨的逃逸問題,提齣瞭在SCR催化單元尾部增設對氨具有高效分解作用的改性SCR催化劑的方法。分彆攷察瞭Cu及Ru等金屬元素對W/V/Ti型SCR催化劑的改性效果。結果錶明,Cu、Ru 兩種金屬元素改性後的催化劑對逃逸氨均有較好的脫硝還原效果及彊化氨的催化分解作用。對氨分解產物分析錶明,Cu改性催化劑對氨的分解產物中NOx轉化率較高,而Ru改性SCR催化劑不僅具有非常高的氨催化氧化活性,同時其分解產物對N2的選擇性能夠達到90%以上。另外,攷察瞭溫度、催化劑預硫化處理、NO等因素對逃逸氨的分解作用的影響,催化劑在300~400℃具有最好的活性,預硫化對氨的分解作用具有抑製作用,尤其對Cu繫催化劑。Ru/SCR催化劑具有很好的抗硫性能,經過預硫化處理後,在NO存在的條件下,NH3去除率能夠達到80%以上,在逃逸氨控製方麵具有應用前景。
위감소연기안법선택성환원최화탈초(NH3-SCR)과정안적도일문제,제출료재SCR최화단원미부증설대안구유고효분해작용적개성SCR최화제적방법。분별고찰료Cu급Ru등금속원소대W/V/Ti형SCR최화제적개성효과。결과표명,Cu、Ru 량충금속원소개성후적최화제대도일안균유교호적탈초환원효과급강화안적최화분해작용。대안분해산물분석표명,Cu개성최화제대안적분해산물중NOx전화솔교고,이Ru개성SCR최화제불부구유비상고적안최화양화활성,동시기분해산물대N2적선택성능구체도90%이상。령외,고찰료온도、최화제예류화처리、NO등인소대도일안적분해작용적영향,최화제재300~400℃구유최호적활성,예류화대안적분해작용구유억제작용,우기대Cu계최화제。Ru/SCR최화제구유흔호적항류성능,경과예류화처리후,재NO존재적조건하,NH3거제솔능구체도80%이상,재도일안공제방면구유응용전경。
In order to reduce the ammonia (unreacted reductant) slipped from ammonia selective catalytic reduction of NOx (NH3-SCR) in the coal-fired power plants flue gas, catalysts which can be used at the tail-end of a SCR unit were put forward and investigated. Cu and Ru were employed as the main dopants to modify commercial SCR catalyst and the modified catalysts display outstanding catalytic activity on both NOx reduction and NH3 abatement. NOx is the main product of NH3 oxidation over Cu modified catalysts, while the selectivity of N2 as the product of catalytic oxidation of NH3 over Ru/SCR catalyst is as high as 90%. The results suggest that the optimal temperature window is 300~400℃ and presulfurization of the catalyst can inhibit the NH3 conversion, especially for the Cu modified catalysts. However, high NH3 conversion was still obtained at 350℃ with 100 ppm NO over Ru/SCR presulfurized with SO2, therefore the Ru modified SCR catalyst should be promising for the selective oxidation of NH3 to N2.