The steel industry is a basic industry supporting the national economy, and it is also an industrial sector with large carbon emissions in the manufacturing sector, and its green and low-carbon transformation is of great significance.

This year, the National Development and Reform Commission and other departments issued the Special Action Plan for energy conservation and carbon reduction in the steel industry, which will "increase the proportion of short-process electric furnace steelmaking" as an important measure to promote the green and low-carbon development of the steel industry, and put forward that "by the end of 2025, the utilization of scrap steel will reach 300 million tons, and the proportion of electric furnace steel production in total crude steel production will strive to increase to 15%".

What is short process EAF steelmaking? In the steel industry, there are two main smelting processes, one is the "blast furnace - converter" long process steel making with iron ore as the main raw material, commonly known as converter steel, the other is the short process electric furnace steel making with scrap as the main raw material, commonly known as electric furnace steel. Different from the long-process steel making, the main raw material of short-process electric furnace steel making is scrap steel, and the process eliminates the relatively high pollution, energy consumption and carbon emissions of coking, sintering, blast furnace iron making and other processes.

What is the significance of developing short-process EAF steelmaking? What will be the next step? The reporter conducted an interview.

Using short-flow electric furnace steelmaking process, the carbon reduction effect is remarkable

Scrap crushing, machine roar, into the scrap processing workshop of Shigang Company of Hesteel Group, 2 large gantry shears and 1 large power crusher are cutting and crushing of strip and plate scrap.

In the electric furnace workshop, two double-shaft scrap preheating DC electric arc furnaces are very prominent. After the scrap is sorted and treated, it is sent to the batching room, loaded into the basket, and then sent to the top of the electric furnace for preheating, and then melted into molten steel by the electric furnace. This electric furnace uses a unique waste preheating method, which can use production waste heat to raise the temperature of scrap steel to 600 to 800 degrees Celsius, thereby reducing the melting time of scrap steel and improving production efficiency. Subsequently, the molten steel flows down the outlet into the ladle and is sent to the refining workshop for refining and vacuum treatment, after which continuous casting is completed. "These processes are not very different from the long process of steelmaking." Yang Weihua, assistant director of steel mill of Shi Steel Company, said.

"Green and low-carbon development is the new requirement and new trend of steel production." Yang Zhuo, deputy minister of the development and construction department of the Stone Steel Company, told reporters that in 2018, when the construction of the new plant was started, the long process of the old plant was abandoned and the short process was firmly chosen.

"Ore, coking coal, coke, pellets, once essential raw materials for steel production, have disappeared from the purchasing list, the use of raw materials into various types of scrap steel, and the working environment is cleaner." Yang Zhuo said. According to preliminary estimates, compared with the old factory, the comprehensive energy consumption of the new factory is reduced by 62% per ton of steel, 46% per ton of molten steel, and 75% per ton of major pollutants such as particulate matter, sulfur dioxide and nitrogen oxides.

In addition, short-process EAF steelmaking has the advantages of flexible production organization and strong adaptability of raw materials. "The long process of steelmaking, the process is one link after another, and the chemical reaction is complex. Even if the market fluctuates and the production needs to be adjusted flexibly, the blast furnace cannot be easily shut down, otherwise it will require a lot of costs to restart. The short process eliminates these problems by not having a blast furnace ironmaking process, and the production organization is more compact and efficient." Yang Weihua said that the short-process process can also flexibly adapt to different types of scrap steel raw materials and convert them into steel products.

At present, China's "blast-converter" long process steelmaking in the total output of crude steel accounted for about 90%. According to the preliminary calculation of the research group of the China Iron and Steel Association (hereinafter referred to as "CISA"), the carbon emission per ton of steel in China's long process steel enterprises in 2021 is about 1.8 tons, of which more than 70% comes from the iron pre-process, and the carbon emission per ton of the whole scrap electric furnace steel enterprises with the iron pre-process is about 0.36 tons, and the carbon reduction effect is significant.

"Pure scrap short-process electric furnace steelmaking is about 1.5 tons less carbon emissions per ton than 'blast furnace - converter' long-process steelmaking, which is the most effective way to reduce carbon dioxide emissions in the steel industry." In the future, one of the main ways to reduce carbon in the steel industry is to develop short-process electric furnace steelmaking." The relevant responsible comrades of CISA believe that to promote energy saving and carbon reduction in the steel industry, the role of "blast-converter" and electric furnace in the first and second half and the contribution of carbon reduction are different, "the total carbon emission reduction in the 'first half' depends on a long process, and the 'second half' to achieve carbon neutrality depends on a short process."

Strong policy support, the rapid development of the industry, the proportion of electric furnace steel is expected to gradually increase

In a scrap recycling and processing base in Xuanhan County, Dazhou City, Sichuan province, trailers shuttle back and forth, carrying scrap steel such as car scrap parts and discarded refrigerator shells from surrounding cities and counties. Here, about 3,000 tons of scrap steel a day are processed and transported to the nearby Hangda Steel mill. "Scrap is the main raw material for short-process steelmaking, accounting for about 80 percent of the company's steelmaking costs." Sichuan Derun Iron and Steel Group Hangda steel plant director Liu Shuguang said.

Electric furnace steelmaking has the advantages of less investment, short construction period, flexible production organization and obvious effect of energy saving and carbon reduction. So, compared to the long process of steelmaking, what is the economy of short process steelmaking? Liu Shuguang to reporters calculate an account --

Let's look at the long process. Recently, the price of 1 ton of iron ore is less than 1,000 yuan, and the iron ore is melted into hot metal by blast furnace ironmaking and other processes, and the cost per ton is more than 2,000 yuan.

Let's look at the short process. At present, the purchase price of 1 ton of scrap steel is more than 2,000 yuan, which is similar to the cost of hot metal for long process steelmaking. However, hot metal is hot and can be used directly for steelmaking without adding other heat sources, while scrap steel is cold and needs to be melted by electrodes at high temperatures to be used for steelmaking. In other words, the short process has a part of the electricity cost.

"Calculated, in the case of labor and other costs are similar, the price of scrap steel per ton is more than 300 yuan lower than the cost of hot metal, and electric furnace steelmaking can have a certain competitiveness." Liu Shuguang said.

In order to reduce the cost of electricity, many electric furnace steel enterprises will make production plans according to the peak and valley electricity price period, and reasonable peak production. In Hangda Steel, the operation time of the electric furnace is from 21 to 15 o 'clock the next day, covering the trough period from 23 to 7 o 'clock the next day, avoiding the peak period from 15 to 21 o 'clock, and the cost can be saved by 50 or 60 yuan per ton of steel.

Although the economy needs to be improved, many surveyed enterprises believe that in the long run, the market competitiveness of electric furnace short-process steelmaking will gradually increase. "With the continuous promotion of new industrialization and new urbanization, the amount of scrap steel will continue to increase, the raw material cost of short process steelmaking will gradually reduce, and the gap with long process steelmaking will gradually narrow." In the international market, many customers have proposed to purchase 'zero carbon steel' or 'low carbon emission steel', and more green and low-carbon electric furnace steel is more popular than converter steel." Yang Zhuo said.

Cisa related research report believes that in the future, China's electric furnace steelmaking will be concentrated in areas rich in scrap resources, relatively scarce iron ore resources, and green electricity advantages, and will develop in three directions in terms of products: First, the electric furnace plant around the city mainly produces construction steel, the second is to produce special steel and high alloy steel products around the equipment manufacturing, and the third is to produce high-grade plates such as "near zero carbon" automobile plates with large volume electric furnaces.

Good news for the development of electric furnace steel is gradually increasing. The relevant responsible comrades of CISA believe that in the future, with the rapid development of the new energy industry, the continuous improvement of differentiated pricing policies across the country, and the increasing abundance of green electricity resources, the electricity cost of electric furnace steelmaking will continue to decrease; The relevant departments have gradually improved the policy support for low-carbon development in terms of capacity replacement, environmental protection, land, etc., the carbon emission constraint has become increasingly stronger, and the progress of short-process electric furnace smelting technology will also help electric furnace steel to achieve greater development.

We will make technologies scientific, development orderly, policies green, and competition fair

According to the World Steel Association data, the proportion of global electric furnace steel in crude steel production in 2023 is about 28.6%. In contrast, there is still a lot of room for the development of short process steel making in China.

In recent years, some places have been actively explored. For example, Sichuan Province, based on the advantages of abundant clean energy such as hydropower, has accelerated the transformation and upgrading of electric furnace steelmaking in recent years. In 2023, the scale of short-process electric furnace steelmaking in Sichuan will reach 13 million tons, and the output of electric furnace steel will account for about 40%. According to China Steel Association statistics, in recent years, 27% of the planned new steelmaking capacity is electric furnace, a total of about 110 million tons, and it is expected that the proportion of electric furnace steel production in China will reach 30% in 2035.

Next, how to develop short-process EAF steelmaking in a scientific and orderly way? The experts and companies interviewed made some suggestions.

-- Improving the supply capacity of scrap steel resources. "The supply of domestic scrap resources is tight, the recycling, processing and distribution system is not perfect, and the cost is relatively high." Yang Zhuo believes that scrap should be established to ensure stable prices to create favorable conditions for stable quality and cost reduction. "At present, Sichuan Province has 19 scrap access enterprises, scrap processing capacity of more than 12 million tons, the industrial scale has basically matched the province's electric furnace steel production capacity." Qing Jiasheng, director of the Material Industry Department of Sichuan Provincial Economic and Information Technology Department, said that it will actively promote the development of scrap recycling, processing and distribution industry and promote the accumulation of scrap resources to advantageous enterprises. It is understood that relevant departments are formulating policy measures to promote scrap output and market standardization.

-- Strengthening the guarantee of electric power resources. Experts said that electricity costs in the electric furnace steel processing costs accounted for a relatively large, short process electric furnace enterprises should be encouraged to build industrial green microgrids according to local conditions, increase the construction of renewable energy and power resource security, encourage enterprises according to the peak and valley electricity price period scientific production plan, reasonable peak production, reduce electricity costs.

-- Improving the manufacturing level of electric furnace equipment. In recent years, the domestic electric furnace equipment manufacturing enterprises have made great progress in the furnace type large-scale, the integration of electric furnace and auxiliary equipment, but there are still shortcomings in the automation equipment and detection. Experts believe that it is necessary to promote electric furnace equipment manufacturing enterprises to cooperate with upstream and downstream enterprises, accelerate the research and development of large-scale and efficient electric furnace equipment technology, and actively develop new electric furnaces with independent intellectual property rights.

Luo Tiejun, vice president of the China Steel Association, said that the development of electric furnace steelmaking should grasp four principles: First, technology and science, electric furnace construction should not only introduce foreign advanced furnace type, but also make good use of domestic advanced furnace type, fully consider the furnace machine matching of electric furnace, not "greed"; The second is to develop orderly, control the rhythm, fully consider the raw material guarantee, and orderly turn the long process into a short process; Third, the policy is green, accelerate the implementation of the carbon emission assessment system in the steel industry, and the whole scrap electric furnace production enterprises listed in the standardized enterprises are no longer included in the "two high" project management; Fourth, the competition is fair, and the new electric furnace without capacity replacement is strictly controlled to ensure the fairness and justice of the construction of electric furnaces.