
In our industry, environmental protection is a question of rationality, efficiency, and profitability. What is the competition around the world doing—and what is voestalpine doing?
Among other things, protecting the environment means lowering emissions of both greenhouse gases and dust, minimizing noise pollution, and dealing more efficiently with natural resources. Given the centrality of technology to their activities, the manufacturing sector worldwide focuses on CO2 emissions. This, then, also is the focus of the following observations, complemented by some of voestalpine’s pioneering projects that are renowned throughout the industry.
Double attention to environmental protection
Two issues are of key importance for avoiding carbon dioxide (CO2) emissions in the steel industry:
- What is the effect of the production of pig iron, crude steel, and the end products made from these materials, and
- What do these products contribute in environmental terms?
In recent decades, the first question brought into being manifold ways to optimize aggregates such as blast furnaces and converters as well as their use. The second question requires a broad, comprehensive view, which accounts above all for steel’s recyclability but also acknowledges that the diversity of the different providers makes serious comparisons almost impossible. Worldwide, the portfolios of steel producers, of suppliers to the mobility industries (automotive, rail, and aerospace), or of the energy industry comprise products whose use is particularly relevant to issues of environmental protection. The so-called life-cycle assessment (“LCA”)—i.e. the comprehensive analysis of raw materials and products, from production to utilization and recycling—is becoming ever more important in this connection.
Could it be even better?
There is very little the industry can still do to further improve their environmental footprint during the manufacturing process: worldwide, they already are too close to the limits imposed on them by the laws of physics. For example, the use of coke per ton of crude steel has been reduced by more than one half since the 1950s (source: Pulm, P., Raupenstrauch, H.: Energy Efficiency in the Iron and Steel Industry. Vienna 2014). At this point of the production chain, for example, achieving significant reductions in CO2 values through the optimization of processes and plants alike would require introducing new processes that entail replacing carbon (a reducing agent) by hydrogen. But the production of hydrogen is energy-intensive and contributes to a positive CO2 footprint only when the electricity used for this purpose is sourced from renewables.
Worldwide, steel producers are trying to push alternative and financially viable processes for decarbonizing the production of steel, i.e. to avoid process-induced CO2 emissions.
Putting resources to best use
Research projects worldwide focus on the use of resources that are engendered by production processes—from the utilization of the waste heat from the production of slag all the way to the utilization of process gases. The World Steel Association (worldsteel) underscores the global nature of these efforts. Using online benchmark tools, its members can access best-practice knowledge to compare key parameters and/or to find suitable approaches for their own optimization plans.
Lighter vehicles
The weight of automotive or aerial vehicles is key to the efficient use of the supplied energy, whether in the form of diesel and gasoline for internal combustion engines, liquid natural gas, kerosene, or electricity. International contracts stipulate the joint goal: lower cars’ CO2 emissions from 130 grams to 95 grams per kilometer by 2020.
The automotive industry’s reduction projects probably are the most well known. Jointly, the suppliers of steel-based structural, auto body, and other parts are aiming for ever lighter steel brands or predominantly steel composite materials which, at minimum, exhibit constant strength and protective characteristics. Via the World Steel Association’s automotive program WorldAutoSteel, for example, they publicize their know-how on the use of ultra-strong steel in automotive engineering.
New processes
Additive manufacturing—so-called 3D printing with metals—enables production processes that conserve resources. The aerospace industry provides a good example of the advantages of this technology: in contrast to the steel version, the Titan model of a safety belt buckle that has been optimized through additive manufacturing weighs about 55% less, i.e. 70 grams instead of 155 grams. This lowers the take-off weight of an Airbus 380 with 853 seats by about 72.5 kilograms. Extrapolated to the plane’s useful life, this would lead to a savings of about 3.3 million liters of jet fuel.(source: Roland Berger GmbH: Additive Manufacturing. A game changer for the manufacturing industry? Study. Munich, 2013).
E-mobility solutions
The growth of e-mobility is increasingly focusing suppliers’ attention on this sector. Aside from the reduction in the weight of automotive vehicles, what is of interest here in particular is the efficiency of the conversion of electrical energy into kinetic energy—and thus the performance of electric motors.
Are we comparing apples and oranges?
If all steel producers worldwide make an effort to optimize their environmental footprint: is there really no benchmark for measuring one’s own status? It is in fact not that easy to put efforts at environmental protection in relation to one another. Internationally, CO2 emissions per ton of crude steel produced are used as a comparative figure. But caution is advised: Often enough it’s like comparing apple and oranges, because the CO2 footprint of different processes—particularly electric arc furnaces (“EAF”) relative to the blast furnace oxygen converter route (also scrap-based versus ore-based)—are comparable only to a very limited extent. Moreover, the use of EAF mills is limited, first and foremost, by the shortfall in the availability of scrap worldwide and potential steel grades.
But one thing is certain: as far as the prevention of CO2 emissions is concerned, voestalpine is an industry leader. The voestalpine Group ranks third in worldsteel’s global ranking thanks to its long-standing, consistent strategy, comprehensive investments, and the technological know-how of its personnel
More informations to the topic environment: https://www.voestalpine.com/environment