ANNEX BAT CONCLUSIONS FOR THE NON-FERROUS METALS INDUSTRIES

1.3. BAT CONCLUSIONS FOR ALUMINIUM PRODUCTION INCLUDING ALUMINA AND ANODE PRODUCTION

1.3.2. Anode production

1.3.2.1. Air emissions

1.3.2.1.1. Dust, PAH and fluoride emissions from the paste plant
BAT 58. In order to reduce dust emissions to air from a paste plant (removing coke dust from operations such as coke storage and grinding), BAT is to use a bag filter.
BAT-associated emission levels: See Table 7.
BAT 59. In order to reduce dust and PAH emissions to air from a paste plant (hot pitch storage, paste mixing, cooling and forming), BAT is to use one or a combination of the techniques given below.
	Technique
a	Dry scrubber using coke as the adsorbent agent, with or without precooling, followed by a bag filter
b	Regenerative thermal oxidiser
c	Catalytic thermal oxidiser
Descriptions of the techniques are given in Section 1.10.	
BAT-associated emission levels: See Table 7.

Table 7
BAT-associated emission levels for dust and BaP (as an indicator of PAH) emissions to air from a paste plant
Parameter	Process	BAT-AEL (mg/Nm3)
Dust	Hot pitch storage, paste mixing, cooling and forming Removing coke dust from operations such as coke storage and grinding	2-5
BaP	Hot pitch storage, paste mixing, cooling and forming	0,001-0,01
As a daily average or as an average over the sampling period.		
As an average over the sampling period.		
The associated monitoring is in BAT 10.

1.3.2.1.2. Dust, sulphur dioxide, PAH and fluoride emissions from the baking plant
BAT 60. In order to reduce dust, sulphur dioxide, PAH and fluoride emissions to air from a baking plant in an anode production plant integrated with a primary aluminium smelter, BAT is to use one or a combination of the techniques given below.
	Technique	Applicability
a	Use of raw materials and fuels containing a low amount of sulphur	Generally applicable for reducing SO2 emissions
b	Dry scrubber using alumina as the adsorbent agent followed by a bag filter	Generally applicable for reducing dust, PAH and fluoride emissions
c	Wet scrubber	Applicability for reducing dust, SO2, PAH and fluoride emissions may be limited in the following cases: very high off-gas flow rates (due to the significant amounts of waste and waste water generated) in arid areas (due to the large volume of water necessary and the need for waste water treatment)
d	Regenerative thermal oxidiser in combination with a dust abatement system	Generally applicable for reducing dust and PAH emissions.
Descriptions of the techniques are given in Section 1.10.		
BAT-associated emission levels: See Table 8.

Table 8
BAT-associated emission levels for dust, BaP (as an indicator of PAH) and fluoride emissions to air from a baking plant in an anode production plant integrated with a primary aluminium smelter
Parameter	BAT-AEL (mg/Nm3)
Dust	2-5
BaP	0,001-0,01
HF	0,3-0,5
Total fluorides	≤ 0,8
As a daily average or as an average over the sampling period.	
As an average over the sampling period.	
The associated monitoring is in BAT 10.
BAT 61. In order to reduce dust, PAH and fluoride emissions to air from a baking plant in a stand-alone anode production plant, BAT is to use a pre-filtration unit and a regenerative thermal oxidiser followed by a dry scrubber (e.g. lime bed).
BAT-associated emission levels: See Table 9.

Table 9
BAT-associated emission levels for dust, BaP (as an indicator of PAH) and fluoride emissions to air from a baking plant in a stand-alone anode production plant
Parameter	BAT-AEL (mg/Nm3)
Dust	2-5
BaP	0,001-0,01
HF	≤ 3
As a daily average.	
As an average over the sampling period.	
The associated monitoring is in BAT 10.