Division 32

United Kingdom

BAT is to reduce dust emissions from the waste gases of the melting furnace by using one or a combination of the following techniques:

Technique^f1	Applicability
A description of the secondary treatment systems is given in Sections 1.10.1 and 1.10.7.
(i) Reduction of the volatile components by raw material modifications The formulation of batch compositions without boron compounds or with low levels of boron is a primary measure for reducing dust emissions which are mainly generated by volatilisation phenomena. Boron is the main constituent of particulate matter emitted from the melting furnace	The application of the technique is limited by proprietary issues, since the boron-free or low-boron batch formulations are covered by a patent
(ii) Filtration system: electrostatic precipitator or bag filter	The technique is generally applicable. The maximum environmental benefits are achieved for applications on new plants where the positioning and characteristics of the filter may be decided without restrictions
(iii) Wet scrubbing system	The application to existing plants may be limited by technical constraints; i.e. need for a specific waste water treatment plant

Table 22

BAT-AELs for dust emissions from the melting furnace in the continuous filament glass fibre sector

Parameter	BAT-AEL^f2
Values at levels of < 30 mg/Nm³ (< 0,14 kg/tonne melted glass) have been reported for boron-free formulations, with the application of primary techniques.
The conversion factor reported in Table 2 (4,5 × 10^–3) has been applied.
Parameter	mg/Nm³	kg/tonne melted glass^f3
Dust	< 10 – 20	< 0,045 – 0,09

Annotations

f1: A description of the secondary treatment systems is given in Sections 1.10.1 and 1.10.7.
f2: Values at levels of < 30 mg/Nm³ (< 0,14 kg/tonne melted glass) have been reported for boron-free formulations, with the application of primary techniques.
f3: The conversion factor reported in Table 2 (4,5 × 10^–3) has been applied.