公开(公告)号：US20110002830A1

公开(公告)日：2011-01-06

申请号：US12829671

申请日：2010-07-02

申请人： William H. Sun ,  William E. Cummings ,  Piers de Havilland ,  Paul G. Carmignani ,  John M. Boyle

发明人： William H. Sun ,  William E. Cummings ,  Piers de Havilland ,  Paul G. Carmignani ,  John M. Boyle

IPC分类号： B01D53/56 ,  B01J8/02

CPC分类号： B01D53/8631 ,  B01D53/90

摘要： A preferred apparatus arrangement utilizes the enthalpy of the flue gas, which can be supplemented if need be, to convert urea (30) into ammonia for SCR. Urea (30), which decomposes at temperatures above 140 .degree. C., is injected (32) into a flue gas stream split off (28) after a heat exchanger (22), such as a primary superheater or an economizer. Ideally, the side stream would gasify the urea without need for further heating; but, when heat is required it is far less than would be needed to heat either the entire effluent (23) or the urea (30). This side stream, typically less than 3% of the flue gas, provides the required temperature and residence time for complete decomposition of urea (30). A cyclonic separator can be used to remove particulates and completely mix the reagent and flue gas. This stream can then be directed to an injection grid (37) ahead of SCR using a blower (36). The mixing with the flue gas is facilitated due to an order of magnitude higher mass of side stream compared to that injected through the AIG in a traditional ammonia-SCR process.

摘要翻译： 优选的装置装置利用烟道气的焓，如果需要，可以补充将尿素（30）转化成氨用于SCR。 尿素（30），其在高于140℃的温度下分解。 在诸如初级过热器或节能器的热交换器（22）之后，将（32）注入（32）到分离（28）的烟道气流中。 理想地，侧流将气化尿素而不需要进一步加热; 但是当需要加热时，它远远小于加热整个流出物（23）或尿素（30）所需要的热量。 通常小于3％烟道气的侧流提供了完全分解尿素（30）所需的温度和停留时间。 旋风分离器可用于除去微粒并完全混合试剂和烟道气。 然后可以使用鼓风机（36）将该流引导到SCR前方的注入格栅（37）。 与通过传统氨SCR工艺中的AIG注入的侧流相比，与烟道气的混合更容易。