Conventional production of pig iron and steel generates air pollutants such as carbon dioxide (CO2) as well as sulfur dioxide (SO2) and nitrogen oxides (NOX) simply for reasons related to processes and raw materials.
voestalpine fully complies with the relevant statutory thresholds. These parameters are verified and the annual loads determined by means of continuous measurements, periodic tests, and material flow analyses. State-of-the-art scrubbing facilities (i.e., end-of-pipe measures) are utilized in addition to continual process optimization (i.e., process integrated (PI) measures) to minimize remaining emissions.
Over the past several decades, the voestalpine Group substantially lowered the level of its emissions thanks to extensive environmental measures and innovations in process technology. Given existent steel production technologies, the residual air emissions are the minimum achievable.
Greenhouse gas emissions
The direct greenhouse gas emissions (Scope 1) of the voestalpine Group’s roughly 120 production facilities rose in calendar year 2021 by 16.2% to 14.5 million tons of CO2 equivalents, after declining the previous year on account of the COVID-19 crisis. In Austria, the Group’s plants in Linz and Donawitz that use the blast furnace route to produce crude steel account, respectively, for 9.6 million tons and 3.1 million tons thereof.
Over and above carbon dioxide, the emissions data also include two other greenhouse gases, specifically, methane and nitrous oxide.
In addition to the direct (Scope 1) emissions, the indirect greenhouse gas emissions (Scope 2 + Scope 3) were also compiled and analyzed in accordance with the EU’s environmental footprint (EF) 3.0 climate change methodology.
Scope 1 emissions
In millions of tons of CO2e
Scope 2 facility based: 0.73 million tons of CO2e
Direct and indirect greenhouse gas emissions 2021
In millions of tons of CO2e
SO2 emissions
The use of particular raw materials—especially coal and coke—introduces sulfur into the production process. Additional processing steps and the use of by-products such as coke oven gas (COG) and blast furnace gas (BFG) for thermal recycling generates sulfur dioxide (SO2).
While the specific SO2 emissions in calendar year 2021 were 0.44 g/t of product and thus less than the previous year’s value of 0.46 kg, in absolute terms, SO2 emissions rose from 4.4 kt to 4.6 kt for production-related reasons.
SO2 emissions
kt
Specific SO2 emissions
kg/t product
NOX emissions
Nitrogen oxides are generated through the operation of industrial furnaces and thermal recycling of by-product gases.
Due to the renewed increase in production, voestalpine’s absolute NOX emissions climbed in calendar year 2021 from 5.0 kt to 5.9 kt. The specific NOX emissions per ton of product were 0.55 kg (previous year: 0.53 kg).
NOx emissions
kt
Specific NOx emissions
kg/t product
Captured dust emissions
Dust-laden exhaust air and exhaust gases that occur during production are captured and channeled to dedusting systems using state-of-the-art processes and equipment.
In calendar year 2021, the captured dust emissions per ton of product remained low both in absolute terms (0.35 kt) and specifically (33 g).
Captured dust emissions
kt
Specific captured dust emissions
g/t of product
Organic air pollutants
Organic air pollutants (i.e., volatile organic compounds – VOC) are generated primarily during the thermal process stages of crude steel production as well as during the associated combustion processes.
In recent years, voestalpine commissioned several technically sophisticated pieces of equipment to cut VOC emissions. This made it possible to achieve a substantial decline in the emission of organic air pollutants. In calendar year 2021, VOC emissions per ton of product were 0.16 kt (2020: 0.15 kt) absolutely and 15 g (2020: 16 g) specifically.
VOC emissions
kt
Specific VOC emissions
g/t of product
