BOILER AND A METHOD FOR NOx EMISSION CONTROL FROM A BOILER

Patent metadata

Field	Value
Publication number	US-2016003473-A1
Application number	US-201514789093-A
Country	US
Kind code	A1
Filing date	Jul 1, 2015
Priority date	Jul 4, 2014
Publication date	Jan 7, 2016
Grant date	—

Abstract

A boiler includes an enclosure having at least a supply for fuel and oxidizer and at least a supply for a SNCR reagent. The supply for the SNCR reagent includes at least a regulation valve for the SNCR reagent. The boiler includes at least a sensor for measuring information indicative of the NO x concentration over at least one given enclosure cross section. The boiler includes a controller connected to the at least a sensor and to the at least a regulation valve. The controller regulates the SNCR reagent supply according to the measured information indicative of the NO x concentration.

First claim

1 . A boiler comprising:
an enclosure having at least a supply for fuel and oxidizer and at least a supply for a SNCR reagent, wherein the supply for the SNCR reagent includes at least a regulation valve for the SNCR reagent; at least a sensor for measuring an information indicative of the NO x concentration over at least one given enclosure cross section; and a controller connected to the at least a sensor and to the at least a regulation valve; the controller for regulating the SNCR reagent supply according to the measured information indicative of the NO x concentration.

2 . The boiler of claim 1 , wherein the at least a supply for a SNCR reagent comprises at least a lance housed in the enclosure.

3 . The boiler of claim 2 , wherein the at least a lance is also connected to the supply for oxidizer.

4 . The boiler of claim 3 , wherein the supply for oxidizer is an oxidizer overfire supply.

5 . The boiler of claim 3 , wherein the at least a lance includes an elongated body with at least one entrance for oxidizer or SNCR reagent and nozzles, and wherein at least an injector for SNCR reagent or oxidizer is housed within the elongated body.

6 . The boiler of claim 5 , wherein the entrance is connected to the supply for oxidizer and the at least an injector is connected to at least a supply for SNCR reagent.

7 . The boiler of claim 6 , wherein the lance comprises a number of injectors housed at different longitudinal positions over the lance length.

8 . The boiler of claim 1 , wherein the sensor is a temperature sensor.

9 . The boiler of claim 2 , wherein the enclosure houses heat exchanging surfaces, wherein the at least a lance is mechanically connected to the heat exchanging surfaces.

10 . The boiler of claim 2 , wherein the enclosure houses heat exchanging surfaces, wherein the at least a lance is supported by the heat exchanging surfaces.

11 . A method for NO x emission control from a boiler,
wherein the boiler includes an enclosure having at least a supply for fuel and oxidizer and at least a supply for a SNCR reagent, the method comprising: measuring an information indicative of the NO x concentration over at least one given enclosure cross section, regulating the SNCR reagent supply according to the measured information indicative of the NO x concentration, and injecting the reagent into the enclosure.

12 . The method of claim 11 , wherein the measuring includes locally measuring information indicative of the NO x concentration over at least one given enclosure cross section over a number of zones (AA-GE), and
the regulating includes regulating the SNCR reagent supply according to the measured information indicative of the NO x concentration in each zone (AA-GE).

13 . The method of claim 12 , wherein the locally measuring includes measuring a plurality of information over at least a cross section of the enclosure.

14 . The method of claim 11 , further comprising mixing the SNCR reagent with oxidizer and injecting the mixture.

15 . The method of claim 11 , wherein the measuring information indicative of the NO x concentration includes measuring at least a temperature.

Assignees

• Alstom Technology Ltd

Inventors

• Hilber Thomas
• Schnieder Klaus

Classifications

• F23J2219/20

  Non-catalytic reduction devices · CPC title

• F23J15/04 Primary

  using washing fluids {(scrubbers for removing solids only F23J15/022)} · CPC title

• F23J7/00

  Arrangement of devices for supplying chemicals to fire · CPC title

• B01D53/56

  Nitrogen oxides (B01D53/60 takes precedence) · CPC title

• B01D53/346

  Controlling the process · CPC title