When we talk about low carbon emitting steel, these terms need to be used correctly!

Although steel production has been powered by coal since the Industrial Revolution, the steel industry, like other industries, is transitioning toward a future in which emissions of carbon dioxide and other greenhouse gases are significantly reduced. However, the relevant terminology in the industry has not been clearly defined, and the same word may mean completely opposite meanings between “I think” and “you think”.
For example, we often mention “green steel”. Some people think that it is just a marketing term with neither definition nor scope. You can use it if you want. Others think that it is a professional term that requires official certification and companies want to use it. The terminology used to define one’s own products must cover the entire scope of sustainable development. Although the ideas of these two groups of people are a bit extreme, how “green” steel can be called “green steel”? Is “green steel” “clean steel” or “zero carbon steel”? Where is the dividing line between “net zero carbon steel”, “zero carbon steel” and “low carbon steel”? In order to clarify these concepts, the World Steel Association attempts to standardize the definitions of some terms in this article.
“Low carbon emission steel”: In 2021, although most steel is still produced using fossil fuels as reducing agents, many steel companies have developed or are developing some technologies that can significantly reduce carbon emissions in core steel processes. This has given rise to a whole new range of steel products – low carbon emission steels. For example, two companies, ThyssenKrupp and Nippon Steel, have launched a series of experiments on the use of hydrogen in blast furnaces, with the aim of significantly reducing carbon dioxide emissions in the steel production process; Emirates Steel Company in the United Arab Emirates, from iron smelting plants every year 800,000 tons of carbon dioxide are captured in the generated carbon dioxide-enriched coal gas, and then injected into mature oil fields for permanent storage; HBIS Group is building a hydrogen metallurgical direct reduced iron demonstration project with an annual production capacity of 1.2 million tons, using green hydrogen and blue hydrogen , exploring a “zero-carbon emission metallurgical route” with practical significance; ArcelorMittal is building a large-scale facility in Ghent, Belgium, to convert waste gas from steel plants into ethanol. The converted ethanol can be used to produce synthetic fuels wait. In 2018, Shougang Group also began operating a similar commercial facility, producing 30 million liters of ethanol for commercial sale in the first year of operation.
Such examples abound in the global steel industry. In 2019, Nucor Steel built the first wind energy-powered steelmaking plant in the United States in Missouri. This is a cooperative project between Nucor Steel Company and the local utility department. After the two parties reach a power purchase agreement, they will supply a steady stream of clean electricity to the above-mentioned steelmaking plant. In addition, Evraz Group’s Rocky Mountain Steel Company in Colorado, USA, is trying to shift from coal power generation to solar power generation and will build the country’s largest on-site solar power plant; Brazil’s Green Steel Company is using 100% charcoal Produce low-carbon emission steel; Tata Steel is developing a new melt smelting process, the HIsarna process, which produces iron without the use of coke ovens or sintering facilities and uses carbon capture technology (CCS) to capture gas of carbon dioxide.
Although the meaning of “low carbon” will change with the development and changes of regulations, social expectations and technology, the World Steel Association believes that steel produced using the above new technologies and processes can be regarded as low carbon emission steel. However, there are disagreements within the industry and relevant agencies on how to accurately call this type of steel, with the World Steel Association preferring to call it “low carbon emission steel”. World Steel Association believes that this expression is more convenient, intuitive and easy to understand. Many institutions choose to call it “green steel.” In fact, they call this type of steel “green steel” to highlight their environmental awareness to assist marketing. The World Steel Association believes that “green steel” can refer to many types of steel, such as steel produced using breakthrough technologies, steel produced from scrap steel, steel that is reused and remanufactured, or through the purchase of carbon emission indicators or carbon steel. Steel produced by the company (it does not actually reduce carbon emissions in the production process of steel products). Therefore, the World Steel Association prefers to use the expression “low carbon emission steel”.
“Zero-carbon steel”: If steel companies want to produce true “zero-carbon steel”, they must not emit any carbon dioxide during the production process, and the requirements are very strict. Although many technologies in the industry are currently developing in this direction, the expression “zero carbon steel” is too absolute. Manufacturers may produce residual carbon emissions in the supply chain due to the use of carbon-containing electrodes or the use of natural gas in associated processes. If carbon sinks are not used to offset such carbon emissions, then “zero carbon steel” cannot be produced. Not to mention, carbon is the core component of steel and distinguishes it from pure iron. Worldsteel believes that although the alloyed carbon can be obtained from non-fossil energy sources, the presence of carbon is sufficient to indicate that the term “zero carbon steel” is inappropriate.
“Net Zero Carbon Steel”/“Carbon Neutral Steel”: Steel is called steel if the amount of greenhouse gases emitted into the atmosphere during its production is balanced by the amount of emissions collected from the atmosphere using carbon sequestration facilities. “Net zero carbon steel” or “carbon neutral steel”. To achieve true carbon neutrality, the production of “net-zero carbon steel” may require “carbon offsets” in other links. It should be noted that if a production company believes that it has achieved carbon neutrality in production and operations, it must ensure the high transparency of its production boundaries, statistical methods, and the high credibility of the compensation methods it adopts.
“Zero fossil fuel steel”: At present, a few steel companies around the world have begun to promote “zero fossil fuel steel”. The so-called “zero fossil fuel steel” means that neither any fossil fuels (such as coal or natural gas) nor any energy derived from fossil fuels are used in the steel production process. It is important to note that while all “zero fossil fuel steels” are low carbon emission steels, not all low carbon emission steels can be called “zero fossil fuel steels”. For example, low-carbon-emitting steel produced using carbon capture and storage technology may still use natural gas or coal, although no carbon dioxide is emitted during the production process.
“Clean steel”: This is a technical term commonly used in the steel industry and refers to steel that contains lower levels of impurities, oxides, dopants, or steel that contains low or ultra-low levels of metallic dissolved carbon. The World Steel Association used this term in “Clean Steel Production Process Technology” released in 2004, and it has a specific meaning. Therefore, in some specific contexts regarding climate change, worldsteel does not use the term “clean steel”.
“Decarbonization”: The World Steel Association generally does not use the term “decarbonization” to describe steel production. What steel companies need to eliminate is the greenhouse gas or carbon dioxide produced during the steel production process, not the steel production process itself. This is similar to the reason why the World Steel Association does not adopt “zero carbon steel”. Many promising breakthrough technologies still require the use of carbon as a chemical reducing agent but prevent harmful greenhouse gases from being released into the atmosphere. While emissions from the steel industry will eventually be “decarbonized,” the ironmaking process itself may not be truly decarbonized. The breakthrough technology produces low-carbon-emitting steel in a completely different way than traditional blast furnace, direct reduced iron or electric furnace technologies. Breakthrough technologies currently known to be under development in the industry include: hydrogen reduction technology, iron ore electrolysis technology, carbon capture, utilization and storage technology (CCUS), etc.
Hydrogen is a key media substance. Using hydrogen as a reducing agent can significantly reduce greenhouse gas emissions in the steel industry. Hydrogen is often given a certain color prefix due to its different “carbon reduction capabilities” and is also divided into two categories: “low carbon hydrogen” and “fossil hydrogen”.
The World Steel Association stated that the “low carbon hydrogen” mentioned in the industry specifically includes the following three types: one is green hydrogen produced through the electrolysis of water process using clean electricity; the other is the comprehensive use of steam methane reforming process and CCS technology, using The third is blue hydrogen produced from natural gas, hydrogen produced by electrolysis using other low-carbon electricity (such as nuclear power), or hydrogen produced using CCS technology alone.
“Fossil hydrogen” refers to hydrogen produced using fossil fuels but not using carbon reduction processes. It mainly includes two types: one is hydrogen produced using natural gas using the steam methane reforming process, but because this process does not use CCS technology, it The carbon dioxide produced will be emitted into the atmosphere, so it is called gray hydrogen; the second is hydrogen produced using coal gasification technology. The greenhouse gas emission level in producing this hydrogen is much higher than other hydrogen, which is called brown hydrogen or black hydrogen. .