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Toolkit for Identification and Quantification of Releases of Dioxins, Furans and Other Unintentional POPs PART III Annexes |
Annex 21 Complementary information to source category 2f Lead Production
Overview of recent revisions
The majority of PCDD/PCDF emission factors are confirmed for this source category except for class 3. A new emission factor has been assessed regarding class 4. Some new PCB and HCB emission factors are also proposed.
Table III.21.1 PCB emission factors for source category 2f Lead Production
2f Lead Production Emission Factors (µg TEQ/t lead) Classification Air Water Land Product Residue 1 Lead production from scrap containing PVC 2 2 Lead production from PVC/Cl2 free scrap, some APCS 0.2 0.1 3 Lead production from PVC/Cl2 free scrap in highly efficient furnaces, with APC including scrubbers 0.002 4 Pure primary lead production Table III.21.2 HCB emission factors for source category 2f Lead Production
2f Lead Production Emission Factors (µg/t lead) Classification Air Water Land Product Residue 1 Lead production from scrap containing PVC 1,000 2 Lead production from PVC/Cl2 free scrap, some APCS 1,000 3 Lead production from PVC/Cl2 free scrap in highly efficient furnaces, with APC including scrubbers 1,000 4 Pure primary lead production 350 Emission factors for PCB/HCB are provided with:
- A medium level of confidence for class 2 (PCB) and classes 3 and 4 (HCB), as emission factors are not based on expert judgment but are not derived from a broad geographical coverage;
- A low level of confidence for classes 1 and 3 (PCB) and classes 1 and 2 (HCB), as emission factors are based on extrapolations and expert judgment.
Derivation of emission factors
Release to Air
Test data for production of lead from scrap materials are available from Germany (SCEP 1994, LUA 1997), Sweden, Belgium, the Netherlands (LUA 1997), and the USA (USEPA 2000b). In these countries, typically PVC is separated from batteries and facilities tested had dust abatement by fabric filters and some also had scrubbers. In US tests the addition of a scrubber reduced air emissions by approximately 90% (USEPA 2000b).
In the USA, the following emission factors were determined for the various types of secondary lead smelters (USEPA 2000b): Blast furnaces = 0.63-8.81 μg TEQ/t lead, reverberatory/co-located furnace = 0.05-0.41 μg TEQ/t lead, and rotary furnace = 0.24-0.66 μg TEQ/t lead. Emissions to air were about 10-times higher before any scrubber/APCS than in the purified air. The average emissions were 8.31 and 0.63 ng TEQ/m³ for blast furnaces before and after the scrubber, respectively; 0.41 and 0.05 ng TEQ/m³ for reverberatories/collocated furnaces before and after the scrubbers, respectively; and 0.24 and 0.66 ng TEQ/m³ for rotary kilns before and after the scrubbers, respectively.
European measurements gave 5 μg TEQ/t of lead in Belgian blast furnaces and in the Netherlands for a lead smelter, which processed contaminated scrap but was equipped with lime injection and fabric filter (1.3 ng TEQ/m³ were measured). German measurements were 0.14-0.27 ng TEQ/Nm³ at rotary kilns; 0.59 ng TEQ/Nm³ at a shaft furnace, 0.09-0.18 ng TEQ/Nm³ at short rotary kilns and 0.14-0.27 ng TEQ/Nm³ at rotary kilns. A recycling lead smelter for used car batteries had emissions between 0.2 and 0.3 ng TEQ/Nm³. The report, does not give average emission factors for the German secondary lead industry (LUA 1997). The Italian study reported an emission factor of 5.0 μg TEQ/t of Pb for the production of secondary lead from pretreated vehicle batteries in rotary furnaces equipped with wet scrubbers.
The concentrations measured at the Thai secondary lead smelter (rotary kilns with afterburners, cyclone and bagfilter) ranged from 0.021 to 0.032 ng I-TEQ/m³ with a mean of 0.027 ng I-TEQ/m³ for the line with the combined flue gas streams and from 0.06 to 0.11 ng I-TEQ/m³ with a mean of 0.089 ng I-TEQ/m³ for line, which only operated the rotary kiln at the operational O2 content of about 19%. The latter concentration corresponds to an emission factor of 10 µg TEQ/t of lead and therefore very well fits into class 2 (EF = 8 μg TEQ/t of lead). Concentrations measured in China (Ba et al. 2009) led to an emission factor estimate of 0.64 µg TEQ/t. The one calculated from measurements carried out in South Korea reaches 3.14 µg TEQ/t (Yu et al. 2006). The CORINAIR database provides a higher emission factor of 20 µg TEQ/t for secondary lead production sites where the efficiency of APC devices is low. Finally, data collected on three Japanese plants corresponding to class 3 were used to assess an emission factor of 0.06 µg TEQ/t (Iwata et al. 2008).
An emission factor of 8 μg TEQ/t of lead produced is to be used for furnaces fitted with fabric filters where PVC is excluded from battery separators (class 2). An estimated factor of 80 μg TEQ/t is used where PVC may be present (class 1), this assessment being highly uncertain as no references are supporting it. For class 3, it is proposed to use an emission factor of 0.05 μg TEQ/t for high technology furnaces and sophisticated flue gas cleaning equipment including scrubbers (concentrations well below 0.1 ng TEQ/m³).
For primary lead production (class 4), an emission factor is proposed, based on measurement results from two plants in Japan (Iwata et al. 2008).
PCB air emissions from secondary lead production have been studied in China (Ba et al. 2009) and in South Korea (Yu et al. 2006). The former study derived an emission factor of 0.0037 µg TEQ/t, whereas the latter derived an emission factor of 0.31 µg TEQ/t. A mean value of 0.2 µg TEQ/t is thus proposed for class 2. Assuming that PCB emissions are lower than 10% of PCDD/PCDF emissions (expressed as TEQ), emission factors are proposed for class 1 (2 µg TEQ/t) and for class 3 (0.002 µg TEQ/t).
Regarding HCB air emissions, a Japanese reference gives emission factors of 990 µg/t for a lead recovery plant and of 340 µg/t for a lead primary melting plant (Iwata et al. 2008). Therefore a common emission factor of 1,000 µg/t is proposed for classes 1 to 3 and an emission factor of 350 µg/t for class 4.
Release to Water
A release to water may result where effluents are discharged. There is not enough data to estimate an emissions factor. The presence of any liquid discharge should be noted and its source within the process recorded.
Release to Land
No release to land is expected.
Release in Products
No PCDD/PCDF is expected in the refined lead.
Release in Residues
PCDD/PCDF will be present in flue gas treatment residues. Tests in Germany (SCEP 1994) reported concentrations between 2,600 and 3,100 ng TEQ/kg in dusts from a shaft furnace. Any use of residues as raw materials in other processes may result in transfer of PCDD/PCDF. An emission factor of 50 μg TEQ/t of Pb has been derived from the ENEA study (ENEA 2003). This emission factor has been confirmed by subsequent references from China (Ba et al. 2009) and South Korea (Jin et al. 2009).
PCB releases through residues have also been studied in China (Ba et al. 2009). Based on the emission factor reported in China, an emission factor of 0.1 µg TEQ/t is proposed for class 2.
