# Commission Implementing Decision (EU) 2017/1442 of 31 July 2017 establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council, for large combustion plants (notified under document C(2017) 5225) (Text with EEA relevance), Division BAT 73: In order to prevent and/or reduce NOX emissions to air while limiting CO emissions to air from IGCC plants, BAT is to use one or a combination of the techniques given below.

Extent: E+W+S+N.I.

Technique
Description
Applicability
a.
Combustion optimisation
See description in Section 8.3
Generally applicable
b.
Water/steam addition
See description in Section 8.3.
Some intermediate-pressure steam from the steam turbine is reused for this purpose
Only applicable to the gas turbine part of the IGCC plant.
The applicability may be limited due to water availability
c.
Dry low-NOX burners (DLN)
See description in Section 8.3
Only applicable to the gas turbine part of the IGCC plant.
Generally applicable to new IGCC plants.
Applicable on a case-by-case basis for existing IGCC plants, depending on the availability of a retrofit package. Not applicable for syngas with a hydrogen content of > 15 %
d.
Syngas dilution with waste nitrogen from the air supply unit (ASU)
The ASU separates the oxygen from the nitrogen in the air, in order to supply high-quality oxygen to the gasifier. The waste nitrogen from the ASU is reused to reduce the combustion temperature in the gas turbine, by being premixed with the syngas before combustion
Only applicable when an ASU is used for the gasification process
e.
Selective catalytic reduction (SCR)
See description in Section 8.3
Not applicable to IGCC plants operated < 500 h/yr.
Retrofitting existing IGCC plants may be constrained by the availability of sufficient space.
There may be technical and economic restrictions for retrofitting existing IGCC plants operated between 500 h/yr and 1 500 h/yr
Table 43
BAT-associated emission levels (BAT-AELs) for NOX emissions to air from IGCC plants
IGCC plant total rated thermal input(MWth)
BAT-AELs (mg/Nm3)
Yearly average
Daily average or average over the sampling period
New plant
Existing plant
New plant
Existing plant
≥ 100
10–25
12–45
1–35
1–60
As an indication, the yearly average CO emission levels for existing plants operated ≥ 1 500 h/yr and for new plants will generally be < 5–30 mg/Nm3.

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Source: https://www.legislation.gov.uk/eudn/2017/1442/annex/division/7/division/7.1.2/division/1 (the official version)
Page: https://openlegislation.uk/eu-decision-2017-1442/annex/division-7/division-7.1.2/division-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.