Division 1.5.2.4 Emissions of organic compounds
United Kingdom
BAT 30. In order to reduce channelled emissions to air of organic compounds including PCDD/F and PCBs from the incineration of waste, BAT is to use techniques (a), (b), (c), (d), and one or a combination of techniques (e) to (i) given below.
| Technique | Description | Applicability | |
|---|---|---|---|
| (a) | Optimisation of the incineration process | See Section 2.1. Optimisation of incineration parameters to promote the oxidation of organic compounds including PCDD/F and PCBs present in the waste, and to prevent their and their precursors’ (re)formation. | Generally applicable. |
| (b) | Control of the waste feed | Knowledge and control of the combustion characteristics of the waste being fed into the furnace, to ensure optimal and, as far as possible, homogeneous and stable incineration conditions. | Not applicable to clinical waste or to municipal solid waste. |
| (c) | On-line and off-line boiler cleaning | Efficient cleaning of the boiler bundles to reduce the dust residence time and accumulation in the boiler, thus reducing PCDD/F formation in the boiler. A combination of on-line and off-line boiler cleaning techniques is used. | Generally applicable. |
| (d) | Rapid flue-gas cooling | Rapid cooling of the flue-gas from temperatures above 400 °C to below 250 °C before dust abatement to prevent the de novo synthesis of PCDD/F. This is achieved by appropriate design of the boiler and/or with the use of a quench system. The latter option limits the amount of energy that can be recovered from the flue-gas and is used in particular in the case of incinerating hazardous wastes with a high halogen content. | Generally applicable. |
| (e) | Dry sorbent injection | See Section 2.2. Adsorption by injection of activated carbon or other reagents, generally combined with a bag filter where a reaction layer is created in the filter cake and the solids generated are removed. | Generally applicable. |
| (f) | Fixed- or moving-bed adsorption | See Section 2.2. | The applicability may be limited by the overall pressure drop associated with the FGC system. In the case of existing plants, the applicability may be limited by a lack of space. |
| (g) | SCR | See Section 2.2. Where SCR is used for NOX abatement, the adequate catalyst surface of the SCR system also provides for the partial reduction of the emissions of PCDD/F and PCBs. The technique is generally used in combination with technique (e), (f) or (i). | In the case of existing plants, the applicability may be limited by a lack of space. |
| (h) | Catalytic filter bags | See Section 2.2 | Only applicable to plants fitted with a bag filter. |
| (i) | Carbon sorbent in a wet scrubber | PCDD/F and PCBs are adsorbed by carbon sorbent added to the wet scrubber, either in the scrubbing liquor or in the form of impregnated packing elements. The technique is used for the removal of PCDD/F in general, and also to prevent and/or reduce the re-emission of PCDD/F accumulated in the scrubber (the so-called memory effect) occurring especially during shutdown and start-up periods. | Only applicable to plants fitted with a wet scrubber. |
Table 7
BAT-associated emission levels (BAT-AELs) for channelled emissions to air of TVOC, PCDD/F and dioxin-like PCBs from the incineration of waste
| Either the BAT-AEL for PCDD/F or the BAT-AEL for PCDD/F + dioxin-like PCBs applies. | ||||
| The BAT-AEL does not apply if the emission levels are proven to be sufficiently stable. | ||||
| Parameter | Unit | BAT-AEL | Averaging period | |
|---|---|---|---|---|
| New plant | Existing plant | |||
| TVOC | mg/Nm3 | < 3–10 | < 3–10 | Daily average |
| PCDD/F f1 | ng I-TEQ/Nm3 | < 0,01–0,04 | < 0,01–0,06 | Average over the sampling period |
| < 0,01–0,06 | < 0,01–0,08 | Long-term sampling period f2 | ||
| PCDD/F + dioxin-like PCBs | ng WHO-TEQ/Nm3 | < 0,01–0,06 | < 0,01–0,08 | Average over the sampling period |
| < 0,01–0,08 | < 0,01–0,1 | Long-term sampling period | ||
The associated monitoring is in BAT 4.
Annotations
Footnotes
- f1
-
Either the BAT-AEL for PCDD/F or the BAT-AEL for PCDD/F + dioxin-like PCBs applies.
- f2
-
The BAT-AEL does not apply if the emission levels are proven to be sufficiently stable.