meta data for this page
Add this page to your book
Remove this page from your book
2.C.3 - Aluminium Production
|2.C.3||T2, T3||AS||D, CS|
|Key Category||SO₂||NOₓ||NH₃||NMVOC||CO||BC||Pb||Hg||Cd||Diox||PAH||HCB||TSP||PM₁₀||PM₂ ₅|
|2.C.3||-||-||-||-||-||-||-||-||-||-||-/T||L/T (till 2001)||-||-||-|
The category 2.C.3 - Aluminium production is sub-divided into primary aluminium and secondary aluminium production.
In Germany, primary aluminium is produced in electrolytic furnaces with pre-baked anodes. The pre-baked anodes are produced in separate anode production plants, where petroleum coke and tar pitch are mixed subsequently baked. This process produces PAH emissions. Hence, the aluminium production is a trend key category for PAH (TIER-2-method, TIER-3-method).
Secondary aluminium is produced in several different furnace types. According to different scrap qualities, the emissions are varying. The use of hexachloroethane for degassing purposes in refining operations of secondary aluminium production has been prohibited by law in Germany since 2002 resulting in an omission of the source for HCB. But for the period 1990-2001 no data on national emissions of HCB in secondary aluminium industries is available. To overcome this data gap the default emission factor for HCB was used.
The yearly production figures were taken from the annual statistical report of the German association for non-ferrous metals [Lit. 1].
The total quantity of waste gas incurred per tonne of aluminium during the production of primary aluminium was multiplied by an average concentration value formed from several individual figures, from various different plants, with appropriate weighting.
The emission factors are either default values according to the 2019 EMEP/EEA air pollutant emission inventory guidebook [Lit. 2] or determined in research Projects [Lit. 3]. The emission factors also make allowance for fugitive emission sources, such as emissions via hall roofs.
The emission figures used for CO are the results of emission measurements within the context of investment projects. The emission factors for SO2 are calculated from the specific anode consumption. The anodes consist of petrol coke; this material has a specific sulphur concentrations of about 1.2 %, from which an SO2 emission factor of 10.4 kg/t Al can be calculated. The average anode consumption is 430 kg of petrol coke per tonne of aluminium. For primary aluminium production NOx emissions were not yet incorporated in the inventory due to several reasons. But emissions will be below the threshold of significance due to the abatement applied in Germany.
The following table shows some process-related emission factors.
Table 1: Emission factors applied
|pollutant||Activity / Process||EF||unit||Trend|
|HCB (years 1990-2001)||resmelted aluminium||5||g/t||constant|
No recalculations have been carried out compared to last year's Submission.
For more information on recalculated emission estimates for Base Year and 2018, please see the pollutant-specific recalculation tables following chapter 8.1 - Recalculations.
Nitrogen oxides essentially arise from the nitrogen content of the fuels in combustion processes and at temperatures above 1,000 ° C also from air nitrogen. Another source of NOx is the electrolysis in primary aluminium production due to the presence of nitrogen in the anode, which can be oxidized to NOx. All these emission sources resulting from energy related processes are included in 1.A.2.b.
Therefore, all NOx emissions will be reported there. If other sources of NOx have quantitative effects is not known. The inventory compiler will try to get reliable information from the relevant industry association.
Lit. 1: German association for non-ferrous metals (WirtschaftsVereinigung Metalle): Annual statistical report: https://www.wvmetalle.de
Lit. 3: Ökopol, IER, IZT, IfG: Bereitstellung einer qualitätsgesicherten Datengrundlage für die Emissionsberichterstattung zur Umsetzung von internationalen Luftreinhalte- und Klimaschutzvereinbarungen für ausgewählte Industriebranchen Teilvorhaben 2: NE-Metallindustrie, Kalkindustrie, Gießereien.