Reflection on the development ways of steel reduction and carbon reduction in China

The rapid development of China's steel, on the one hand, supports the national defense and infrastructure construction, helping China to become the world's second largest economy;On the other hand, it also produces about 15% of China's total carbon emissions, making it the industry with the largest carbon emissions in China's manufacturing industry.Iron and steel industry has been seeking for new development in a variety of contradictions.Since the reform and opening up, the iron and steel industry for a long time to expand the scale, increase output as the leading, supporting the rapid development of the national economy.After the comprehensive production capacity reaches 1 billion tons of steel, how to appropriately reduce the steel production, as soon as possible to achieve carbon peak, carbon neutral, is a new issue facing the steel industry.

One is to improve the performance of steel and extend the service life, to achieve the reduction of steel.

Although steel has irreplaceable rigid demand, but the quality and performance of steel is very different, with steel industry in order to ensure the quality and performance of products, generally take the coarse generation of thin, thick generation of thin, in light of the way to use steel, which is an important factor affecting the consumption and supply of steel.Under the same demand, there is great potential to improve the quality and performance of steel and realize the reduction of steel.For example, in the construction field where steel consumption is the largest, the use of high-strength steel to replace ordinary steel for transmission towers can reduce the steel consumption by at least 10% or more;The scaffold uses high-strength steel instead of ordinary welded pipe, which can reduce the amount of steel used by about 30%.In manufacturing, reduced steel also has great potential.Taking bearing steel as an example, China's annual output of bearings in 2019 is 20 billion sets, most of which are middle and low-end products. Due to unstable quality, the average service life only reaches half of that of foreign countries, resulting in excessive consumption of steel.Steel experts estimate that about 100 million tons of steel consumption could be reduced by improving the properties and extending the service life of the steel.In 2020, China's steel bar output is 266 million tons. If most of the steel bars are high-grade, the output can be reduced by more than 10%, about 26 million tons.

Second, encourage and support iron and steel enterprises to efficiently convert residual energy and waste heat, improve the rate of spontaneous electricity and reduce carbon emissions.

In the production of iron and steel enterprises, about more than 50% of the energy is converted into coal gas, steam and other waste heat energy.Efficient use of these waste energy and heat power generation, to reduce social power consumption, reduce carbon emissions, and can greatly improve the efficiency of resource utilization.At present, the self-generating rate of surplus energy and waste heat in the iron and steel industry (excluding power generation from externally purchased coal-fired power plants) is 50% on average.In 2019, China produced 996 million tons of steel, with an average electricity consumption of 455 kilowatt-hours per ton of steel, reducing social electricity consumption by 226.59 billion kilowatt-hours, which is equivalent to 2.34 times of the power generation generated by the Three Gorges Project (9.688 billion kilowatt-hours in 2019).In other words, the steel industry relies on technological innovation to efficiently convert more electricity from waste gas and heat than two Three Gorges.At the same time, the steel industry uses less social electricity, which can reduce 240 million tons of carbon dioxide emissions.

Steel and energy experts after many times of investigation and demonstration, it is generally believed that the steel industry energy efficient utilization and efficient transformation technology has been mature, some enterprises have reached more than 90% of the self-electricity rate.During the 14th Five-Year Plan period, based on the annual production of 900 million tons of steel, the steel industry can generate 327.6 billion kilowatt-hours per year from the surplus energy and heat, equivalent to the power generation of three Three Gorges.

From the perspective of carbon emissions, every 1 kilowatt-hour of electricity will emit 1.06 kilograms of carbon dioxide.Increasing the generation rate from 50 percent to 80 percent (adding 122.8 billion KWH of electricity) will reduce another 130 million tons of carbon dioxide emissions.

From the perspective of economic benefit, based on the electricity price of RMB 0.549 per kilowatt-hour, the increase of the self-generating rate from 50% to 80% (new generating capacity of 122.8 billion kilowatt-hours) can reduce the cost and increase the efficiency by RMB 67.4 billion, and the average tonnage of steel power cost will decrease by RMB 75.

At present, the difficulty of reducing carbon efficiency lies not in technology, nor in equipment, but in our long-term habit of grasping steel efficiency, not accustomed to grasping energy efficiency;Used to grasp the value added steel, not used to grasp the energy conversion;Accustomed to focus on single pollution emission control, not accustomed to focus on the residual energy waste heat system emission reduction, efficient utilization.The change of cognition and concept is the key to reduce carbon and increase efficiency.It is suggested that the self-generating rate of residual energy and heat in iron and steel enterprises should be included in the national statistical system and used as an important index to evaluate and examine the enterprises.

Third, adjust tariff policies, moderate restraint of steel exports.

In 2020, due to the COVID-19 epidemic, the demand of the international steel market weakened, and China exported 53.67 million tons of steel, which was reduced by about half from the peak of 112 million tons in 2015.However, according to the actual supply and demand situation of the domestic steel market in recent years, China's annual steel exports are generally 70 million to 80 million tons. A large number of steel exports not only increase energy consumption and carbon emissions, but also boost the price of imported iron ore.

Perfecting the relevant steel export tariff policies and controlling the export of medium and low grade steel can also alleviate the side effects caused by the production capacity of 100 million tons to a certain extent.