公开(公告)号：US5270025A

公开(公告)日：1993-12-14

申请号：US858316

申请日：1992-03-25

申请人： Loc Ho ,  Shih L. Chen ,  William R. Seeker ,  Peter M. Maly

发明人： Loc Ho ,  Shih L. Chen ,  William R. Seeker ,  Peter M. Maly

IPC分类号： B01D53/56 ,  C01B21/00 ,  B01J8/00 ,  C01B17/00 ,  C01B17/20

CPC分类号： B01D53/56 ,  Y02C20/10

摘要： Method for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures are disclosed. The N.sub.2 O emissions are controlled by the introduction of a N.sub.2 O control agent, such as an alkaline compound, into the effluent stream. In addition, the present invention discloses methods for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures while reducing NO.sub.x emissions. Use of an NO.sub.x reducing agent and an N.sub.2 O control agent, such as urea and monosodium glutamate, enlarges the temperature window for effective selective noncatalytic NO.sub.x reduction while significantly eliminating N.sub.2 O emissions commonly experienced with urea injection. Further, the present invention discloses methods for controlling N.sub.2 O emissions from stationary combustion systems having variable flue gas temperatures while reducing SO.sub.x emissions. Use of an NO.sub.x reducing agent, an SO.sub.x reducing agent, and an N.sub.2 O control agent, such as urea, an alkaline-earth metal compound, and an alkali-metal compound, respectively, enlarges the temperature window for effective NO.sub.x and SO.sub.x reductions while significantly eliminating N.sub.2 O emissions.

摘要翻译： 公开了用于控制具有可变烟道气温度的固定燃烧系统的N2O排放的方法。 通过在流出物流中引入N2O控制剂，例如碱性化合物来控制N2O排放。 此外，本发明公开了用于控制具有可变烟道气温度的固定燃烧系统的N2O排放的方法，同时减少NOx排放。 使用NO x还原剂和N2O控制剂，如尿素和谷氨酸钠，可以扩大用于有效选择性非催化NOx还原的温度窗口，同时显着消除尿素喷射通常经历的N2O排放。 此外，本发明公开了用于控制具有可变烟道气温度的固定燃烧系统的N2O排放的方法，同时减少SO x排放。 分别使用NO x还原剂，SOx还原剂和N2O控制剂，如尿素，碱土金属化合物和碱金属化合物，可大大增加有效NOx和SOx还原的温度窗口 消除N2O排放。

公开(公告)号：US5139755A

公开(公告)日：1992-08-18

申请号：US674752

申请日：1991-03-22

申请人： William R. Seeker ,  Shih L. Chen ,  John C. Kramlich

发明人： William R. Seeker ,  Shih L. Chen ,  John C. Kramlich

IPC分类号： B01D53/56

CPC分类号： B01D53/56

摘要： Techniques for enhancing the burnout zone chemistry for NO.sub.x reduction are disclosed. The key parameters for the enhancement of burnout zone chemistry are: (a) a reaction temperature in the range from about 1300.degree. F. to about 1900.degree. F., and optimally in the range from 1400.degree.-1700.degree. F.; (b) a carbon monoxide concentration below about 0.5 percent; and (c) the presence of nitrogenous reducing species. By controlling the stoichiometry associated with reburning to produce a slightly fuel-rich region for selective reducing agent injection, reductions can be achieved at relatively low temperatures which approach those obtained by conventional catalytic reduction.

摘要翻译： 公开了用于增强用于NOx还原的燃烧区化学的技术。 用于增强燃烧区化学的关键参数是：（a）反应温度在约1300°F至约1900°F范围内，最优选在1400°-1700°F范围内。 （b）一氧化碳浓度低于约0.5％; 和（c）含氮还原物质的存在。 通过控制与重燃相关的化学计量，以产生用于选择性还原剂注入的略微富含燃料的区域，可以在相对较低的温度下实现降低，其接近通过常规催化还原获得的那些。

公开(公告)号：US5116584A

公开(公告)日：1992-05-26

申请号：US681697

申请日：1991-04-05

申请人： Shih L. Chen ,  William R. Seeker ,  Loc Ho

发明人： Shih L. Chen ,  William R. Seeker ,  Loc Ho

IPC分类号： B01D53/56

CPC分类号： B01D53/56

摘要： Methods for reducing NO.sub.x emissions from stationary combustion systems having variable flue gas temperatures are disclosed. Use of an annonium salt of an organic acid enlarges the temperature window for effective selective noncatalytic NO.sub.x reduction thereby accounting for variable flue gas temperatures. Currently preferred ammonium salts of organic acids include ammonium formate, ammonium acetate, and ammonium oxalate. Mixtures of urea and either an ammonium salt of an organic acid or a metallic salt of an organic acid provide an even greater temperature window for NO.sub.x reduction. Currently preferred metallic salts of organic acids include Ca(COOH).sub.2, Ca(CH.sub.3 COO).sub.2, Ca(C.sub.2 H.sub.5 COO).sub.2, Mg(COOH).sub.2, Mg(CH.sub.3 COO).sub.2, and Mg(C.sub.2 H.sub.5 COO).sub.2.

摘要翻译： 公开了用于减少具有可变烟道气温度的固定燃烧系统的NOx排放的方法。 使用有机酸的onium盐可以扩大用于有效选择性非催化NOx还原的温度窗口，从而考虑可变的烟气温度。 目前优选的有机酸铵盐包括甲酸铵，乙酸铵和草酸铵。 脲和有机酸的铵盐或有机酸的金属盐的混合物为NOx还原提供了更大的温度窗口。 目前优选的有机酸金属盐包括Ca（COOH）2，Ca（CH 3 COO）2，Ca（C 2 H 5 COO）2，Mg（COOH）2，Mg（CH 3 COO）2和Mg（C 2 H 5 COO）2）。

公开(公告)号：US4851201A

公开(公告)日：1989-07-25

申请号：US73980

申请日：1987-07-15

申请人： Michael P. Heap ,  Shih L. Chen ,  James M. McCarthy ,  David W. Pershing

发明人： Michael P. Heap ,  Shih L. Chen ,  James M. McCarthy ,  David W. Pershing

IPC分类号： B01D53/56 ,  B01D53/60

CPC分类号： B01D53/60 ,  B01D53/56 ,  F02B2275/14 ,  Y02T10/123

摘要： The present invention relates to methods for selectively reducing NO.sub.x so that nitrogen can be removed from emission effluent streams and NO.sub.x emissions can be reduced to very low levels. In addition, the present invention teaches a method whereby NO.sub.x and SO.sub.x may be simultaneously removed from the effluent stream.The present invention teaches the reduction of NO.sub.x with --NH and --CN containing selective reducing agents such as ammonium sulfate, urea, and NH.sub.3. Initially, the selective reducing agent is decomposed in a fuel-rich environment to form highly reactive decomposition products. The reaction of the selective reducing agent to produce its decomposition products, such as NH, NH.sub.2, and related reaction intermediates, takes place in an oxygen-free, fuel-rich decomposition zone with the reaction temperature in the range of from about 300.degree. F. to about 2400.degree. F.After the selective reducing agent is decomposed in the absence of oxygen, the decomposition products are contacted with the effluent stream containing NO.sub.x. At this point the oxygen level of the stream must be carefully controlled to provide an excess of oxygen so that the selective reduction of the NO.sub.x species will occur. It may be necessary at this point to inject air into the effluent stream in order to maintain the proper oxygen-rich (fuel-lean) conditions for NO.sub.x reduction. In this second "reaction zone", NO.sub.x reduction takes place at temperatures of from approximately 500.degree. F. to approximately 2600.degree. F.The present invention can also be used in conjunction with SO.sub.x control technology. Specifically, species used to control SO.sub.x, such as limestone, dolomite, quicklime, and hydrated lime, can be added in conjunction with the selective reducing agent for simultaneous NO.sub.x and SO.sub.x control.

公开(公告)号：US4861567A

公开(公告)日：1989-08-29

申请号：US039324

申请日：1987-04-16

申请人： Michael P. Heap ,  Shih L. Chen ,  James M. McCarthy ,  David W. Pershing

发明人： Michael P. Heap ,  Shih L. Chen ,  James M. McCarthy ,  David W. Pershing

IPC分类号： B01D53/56 ,  B01D53/60

CPC分类号： B01D53/56 ,  B01D53/60 ,  F02B2275/14 ,  Y02T10/123

摘要： The present invention relates to methods for selectively reducing NO.sub.x so that nitrogen can be removed from emission effluent streams and NO.sub.x emissions can be reduced to very low levels. In addition, the present invention teaches a method whereby NO.sub.x and SO.sub.x may be simultaneously removed from the effluent stream.The present invention teaches the reduction of NO.sub.x with cyanuric acid. Initially, cyanuric acid is decomposed to form decomposition products. The reaction of cyanuric acid to produce its decomposition products, such as isocyanic acid or related reaction intermediates, takes place in an oxygen-free, fuel rich, decomposition zone with the reaction temperature in the range of from about 1000.degree. F. to about 3000.degree. F.After the cyanuric acid is decomposed in the absence of oxygen, the decomposition stream is mixed with the effluent stream containing NO.sub.x. At this point the oxygen level of the stream must be carefully controlled to provide an excess of oxygen. It may be necessary at this point to inject air into the effluent stream in order to maintain the proper oxygen-rich (fuel-lean) conditions for NO.sub.x reduction.In the second "reaction zone," reduction takes place at temperatures of from approximately 1200.degree. F. to approximately 2600.degree. F.The present invention can also be combined with SO.sub.x control technology. Specifically, species used to control SO.sub.x, such as limestone, dolomite, quicklime, and hydrated lime, can be added to the cyanuric acid for injection into the effluent stream. Thus, simultaneous NO.sub.x and SO.sub.x control can be achieved.

摘要翻译： 本发明涉及用于选择性还原NOx的方法，以便可以从排放流出物流中除去氮气，并且NOx排放可以降低到非常低的水平。 此外，本发明教导了可以从排出物流中同时除去NOx和SO x的方法。 本发明教导了用氰尿酸还原NOx。 最初，氰尿酸被分解形成分解产物。 氰尿酸产生其分解产物如异氰酸或相关反应中间体的反应在无氧，富燃料的分解区进行，反应温度范围为约1000°F至约3000 在不存在氧的情况下将氰尿酸分解后，将分解流与含有NOx的流出物流混合。 在这一点上，流的氧气含量必须小心控制以提供过量的氧气。 在这一点上可能需要将空气注入流出物流中，以便维持用于NOx还原的适当的富氧（贫燃料）条件。 在第二个“反应区”中，在约1200°F至约2600°F的温度下进行还原。本发明也可以与SOx控制技术组合。 具体地，可以将用于控制SOx的物质，例如石灰石，白云石，生石灰和熟石灰加入用于注入流出物流中的氰尿酸。 因此，可以实现同时的NOx和SOx控制。