Division BAT 158

United Kingdom

In order to reduce dust and metal emissions to air from a refractory-lined crucible for the production of ferro-molybdenum and ferro-vanadium, BAT is to use a bag filter.

BAT-associated emission levels: See Table 46.

Table 46

BAT-associated emission levels for dust emissions to air from ferro-alloys production

Parameter	Process	BAT-AEL (mg/Nm³)
As an average over the sampling period.
As a daily average or as an average over the sampling period.
The upper end of the range can be up to 10 mg/Nm³ for cases where a bag filter cannot be used.
The upper end of the range may be up to 15 mg/Nm³ for the production of FeMn, SiMn, CaSi due to the sticky nature of the dust (caused e.g. by its hygroscopic capacity or chemical characteristics) affecting the efficiency of the bag filter.
Dust emissions are expected to be towards the lower end of the range when emissions of metals are above the following levels: 1 mg/Nm³ for lead, 0,05 mg/Nm³ for cadmium, 0,05 mg/Nm³ for chromium^VI, 0,05 mg/Nm³ for thallium.
Dust	Storage, handling and transport of solid materials Pretreatment operations such as metering, mixing, blending and degreasing Tapping, casting and packaging	2-5^f1
	Crushing, briquetting, pelletising and sintering	2-5^f2 ^f3
	Open or semi-closed submerged arc furnace	2-5 ^f4 ^f5
	Closed submerged arc furnace or closed plasma dust process Refractory-lined crucible for the production of ferro-molybdenum and ferro-vanadium	2-5

Annotations

Footnotes

f1: As an average over the sampling period.
f2: As a daily average or as an average over the sampling period.
f3: The upper end of the range can be up to 10 mg/Nm³ for cases where a bag filter cannot be used.
f4: The upper end of the range may be up to 15 mg/Nm³ for the production of FeMn, SiMn, CaSi due to the sticky nature of the dust (caused e.g. by its hygroscopic capacity or chemical characteristics) affecting the efficiency of the bag filter.
f5: Dust emissions are expected to be towards the lower end of the range when emissions of metals are above the following levels: 1 mg/Nm³ for lead, 0,05 mg/Nm³ for cadmium, 0,05 mg/Nm³ for chromium^VI, 0,05 mg/Nm³ for thallium.