Division BAT 47 In order to prevent or reduce NOX emissions to air from the combustion of iron and steel process gases in boilers, BAT is to use one or a combination of the techniques given below.
United Kingdom
| Technique | Description | Applicability | |
|---|---|---|---|
| a. | Low-NOX burners (LNB) | See description in Section 8.3. Specially designed low-NOX burners in multiple rows per type of fuel or including specific features for multi-fuel firing (e.g. multiple dedicated nozzles for burning different fuels, or including fuels premixing) | Generally applicable |
| b. | Air staging | See descriptions in Section 8.3 | |
| c. | Fuel staging | ||
| d. | Flue-gas recirculation | ||
| e. | Process gas management system | See description in Section 8.2. | Generally applicable within the constraints associated with the availability of different types of fuel |
| f. | Advanced control system | See description in Section 8.3. This technique is used in combination with other techniques | The applicability to old combustion plants may be constrained by the need to retrofit the combustion system and/or control command system |
| g. | Selective non-catalytic reduction (SNCR) | See descriptions in Section 8.3 | Not applicable to combustion plants operated < 500 h/yr |
| h. | Selective catalytic reduction (SCR) | Not applicable to combustion plants operated < 500 h/yr. Not generally applicable to combustion plants of < 100 MWth. Retrofitting existing combustion plants may be constrained by the availability of sufficient space and by the combustion plant configuration | |