Abstract: An intermixer or mixing device with frame structure and suspended bluff body array for use in a stationary (e.g., non-auto) SCR catalyst environment to reduce RMS levels of a mix of NOx pollutant and reduction reagent. SCR reactor apparatus with SCR catalyst module block supported on the intermixer. The SCR reactor apparatus works in an SCR reactor assembly having the SCR reactor apparatus at a first SCR1 layer plus a downstream SCR2 layer. The reduced RMS level of the mix coming from the SCR1 layer is readily able to be treated by the SCR2 layer. An SCR system features the SCR reactor assembly and a combustion source such as a coal-fired plant. Methods of assembly and operating each of the mixing device, SCR reactor apparatus, assembly and system are also featured.

Abstract: An apparatus for reducing emissions that has a combustion turbine that feeds exhaust into a heat recovery steam generator (or HRSG) casing in which is positioned an emission reduction system featuring, in gas flow sequence, a first reducing reductant injector (RRI1), as in an ammonia injection grid, for providing reducing reductant, preferably ammonia, into turbine exhaust travelling within the HRSG, followed by a first SCR reactor positioned downstream of the first RRI1, followed by one of either (i) a turbulence generator (TG) as in a static mixer, or (ii) a second RRI2 as in a second ammonia injection grid, or (iii) an RRI2 with integrated TG supported on injectors of RRI2, then followed by a second SCR reactor. The emission reduction system preferably is free of a separate body oxidation catalyst or a separate body ammonia slip catalyst in an effort to utilize a limited volume within the HRSG. Methods of assembling and operating the ERS or T-H combination with ERS are also featured.

Abstract: An apparatus for reducing emissions that has a combustion turbine that feeds exhaust into a heat recovery steam generator (or HRSG) casing in which is positioned an emission reduction system featuring, in gas flow sequence, a first reducing reductant injector (RRI1), as in an ammonia injection grid, for providing reducing reductant, preferably ammonia, into turbine exhaust travelling within the HRSG, followed by a first SCR reactor positioned downstream of the first RRI1, followed by one of either (i) a turbulence generator (TG) as in a static mixer, or (ii) a second RRI2 as in a second ammonia injection grid, or (iii) an RRI2 with integrated TG supported on injectors of RRI2, then followed by a second SCR reactor. The emission reduction system preferably is free of a separate body oxidation catalyst or a separate body ammonia slip catalyst in an effort to utilize a limited volume within the HRSG. Methods of assembling and operating the ERS or T-H combination with ERS are also featured.