Division 1.5.2.2 Emissions of HCl, HF and SO2

United Kingdom

BAT 27. In order to reduce channelled emissions of HCl, HF and SO₂ to air from the incineration of waste, BAT is to use one or a combination of the techniques given below.

	Technique	Description	Applicability
(a)	Wet scrubber	See Section 2.2	There may be applicability restrictions due to low water availability, e.g. in arid areas.
(b)	Semi-wet absorber	See Section 2.2	Generally applicable.
(c)	Dry sorbent injection	See Section 2.2	Generally applicable.
(d)	Direct desulphurisation	See Section 2.2. Used for partial abatement of acid gas emissions upstream of other techniques.	Only applicable to fluidised bed furnaces.
(e)	Boiler sorbent injection	See Section 2.2. Used for partial abatement of acid gas emissions upstream of other techniques.	Generally applicable.

BAT 28. In order to reduce channelled peak emissions of HCl, HF and SO₂ to air from the incineration of waste while limiting the consumption of reagents and the amount of residues generated from dry sorbent injection and semi-wet absorbers, BAT is to use technique (a) or both of the techniques given below.

	Technique	Description	Applicability
(a)	Optimised and automated reagent dosage	The use of continuous HCl and/or SO₂ measurements (and/or of other parameters that may prove useful for this purpose) upstream and/or downstream of the FGC system for the optimisation of the automated reagent dosage.	Generally applicable.
(b)	Recirculation of reagents	The recirculation of a proportion of the collected FGC solids to reduce the amount of unreacted reagent(s) in the residues. The technique is particularly relevant in the case of FGC techniques operating with a high stoichiometric excess.	Generally applicable to new plants. Applicable to existing plants within the constraints of the size of the bag filter.

Technique

Description

Applicability

(a)

Optimised and automated reagent dosage

The use of continuous HCl and/or SO₂ measurements (and/or of other parameters that may prove useful for this purpose) upstream and/or downstream of the FGC system for the optimisation of the automated reagent dosage.

Generally applicable.

(b)

Recirculation of reagents

The recirculation of a proportion of the collected FGC solids to reduce the amount of unreacted reagent(s) in the residues.

The technique is particularly relevant in the case of FGC techniques operating with a high stoichiometric excess.

Generally applicable to new plants.

Applicable to existing plants within the constraints of the size of the bag filter.

Table 5

BAT-associated emission levels (BAT-AELs) for channelled emissions to air of HCl, HF and SO2 from the incineration of waste

Parameter	BAT-AEL		Averaging period
The lower end of the BAT-AEL range can be achieved when using a wet scrubber; the higher end of the range may be associated with the use of dry sorbent injection.
(mg/Nm³)
Parameter	New plant	Existing plant	Averaging period
HCl	< 2–6 ^f1	< 2–8	Daily average
HF	< 1	< 1	Daily average or average over the sampling period
SO₂	5–30	5–40	Daily average

The associated monitoring is in BAT 4.

Annotations

Footnotes

f1: The lower end of the BAT-AEL range can be achieved when using a wet scrubber; the higher end of the range may be associated with the use of dry sorbent injection.