Under the transformation trend of "double carbon" goal, green development has become a new goal for the development of all walks of life. The concept of green energy has gradually penetrated into all aspects of social operation. Among them, green hydrogen is the indispensable main force.


As a pillar industry of the industrial economy, the iron and steel industry is also experiencing a critical period of green and low-carbon transformation. On February 10, the guiding opinions on promoting the high-quality development of the iron and steel industry jointly issued by the Ministry of industry and information technology, the national development and Reform Commission and the Ministry of ecological environment made it clear that "green and low-carbon development is the top priority of the transformation and upgrading of the iron and steel industry".


Reduction of carbon and hydrogenation, regeneration of iron and steel metallurgy


According to the data of China Iron and Steel Industry Association, the carbon dioxide emission of China's iron and steel industry will be about 1.8 billion tons in 2020. It accounts for 15% of China's total carbon dioxide emissions and more than 60% of the total carbon dioxide emissions of the global steel industry.


In order to achieve the goal of carbon neutralization in China in the future, the iron and steel industry is facing severe challenges. It is imperative to take the road of "green steel" with zero carbonization. In recent years, more and more major steel producing countries around the world have begun to devote themselves to developing breakthrough low-carbon steel-making technology that can significantly reduce CO Ω emissions. Under this background, hydrogen metallurgy came into being.


At present, taking "carbon metallurgy" as the mainstream technical route is the main reason for the large carbon emission of the iron and steel industry. In 2020, the iron and steel industry will use about 300 million tons of coke, and the carbon emission brought by coke alone will be as high as 1.1 billion tons. The substitution of hydrogen metallurgy for carbon metallurgy plays an important role in the realization of carbon neutralization goal in iron and steel industry.


"Carbon metallurgy" to "hydrogen metallurgy" to achieve complementarity and win-win


Hydrogen metallurgy, that is, iron making with hydrogen instead of carbon as reducing agent and energy source, and the reduction product is water, so zero carbon emission can be realized. At present, the mainstream hydrogen metallurgy technology routes are blast furnace hydrogen rich smelting and gas-based direct reduction shaft furnace ironmaking. At present, injection of coke oven gas is typical for domestic blast furnace hydrogen rich smelting. Compared with non injection of coke oven gas, injection of 50m3 / THM coke oven gas reduces carbon emission by 8.61%.


There have been many cases of hydrogen metallurgy technology in the world. In 2021, China Steel Research hydrogen metallurgy center completed the R & D, design and industrial application of injecting by-product hydrogen into the tuyeres of two 1860m3 blast furnaces in Jinnan iron and steel, and realized the engineering practice of continuous and safe hydrogen injection in large blast furnaces for the first time.


It can be seen that the cooperation between hydrogen energy and steel industry is a win-win result. On the one hand, hydrogen energy can help iron and steel enterprises save energy and reduce emissions, extend business and complete transformation; On the other hand, iron and steel enterprises provide more landing applications for hydrogen energy to promote development.


New path of energy conservation and emission reduction, the best combination of "zero carbon" in hydrogen metallurgy


China's crude steel output accounts for about 57% of the world, and is the world's largest steel producer. With the advent of the low-carbon era, hydrogen metallurgy replaces carbon reduction with green hydrogen, which not only has low carbon emission, but also has a very fast reaction speed. By 2050, green hydrogen may become the most economical steelmaking process, accounting for 31% of the market share. Scrap steelmaking is expected to contribute 45% of the output.


According to the white paper on China's hydrogen energy and fuel cell industry, the demand for hydrogen in China's iron and steel industry will reach 9.8 million tons in 2050, of which 1.66 million tons will be provided by coke oven gas, and the remaining 8.14 million tons will come from green hydrogen.


Hydrogen metallurgy is an important technical path for iron and steel production to realize green and low-carbon transformation, and hydrogen metallurgy based on green hydrogen will become one of the largest application industries of green hydrogen. In the future, the iron and steel industry, whether it is the innovation of energy structure, process structure and the application of green hydrogen, will be the best way to achieve low-carbon or even "zero carbon emission".