“Zhanjiang Iron and Steel has formulated an action plan for energy efficiency benchmarking in 2025. In the future, it will rely on the cultivation platform of the Iron and Steel Association’s ‘Double Carbon Best Practice Energy Efficiency Benchmarking Demonstration Plant’ to promote the further deepening of energy efficiency benchmarking work.” The steel industry held on December 9 At the on-site launch meeting of the three-year action plan for energy efficiency benchmarking, Baosteel Zhanjiang Iron and Steel Co., Ltd. Secretary of the Party Committee, Chairman and Commander-in-Chief Liu Daide said.
At the meeting, Liu Dade shared a series of work measures and development plans of Zhanjiang Iron and Steel to pursue the ultimate energy efficiency and achieve benchmark energy consumption. He said that at the end of 2017, Zhanjiang Iron and Steel achieved the “Four Ups” goals of reaching production capacity, standards, efficiency, and consumption, creating the fastest record for large domestic steel mills from commissioning to annual “Four Ups”. Based on this, Zhanjiang Iron and Steel took the lead in realizing “ultra-low emission of exhaust gas, zero discharge of waste water, and no solid waste leaving the factory”, and took the lead in implementing low-carbon metallurgical technology. Advantages such as high recycling rate of water resources.
Accumulated energy saving of 1.1 million tons of standard coal in 5 years
“In the past five years, the comprehensive energy consumption per ton of steel in Zhangang has been decreasing year by year. In 2022, compared with 2017 (the year of full production), it will decrease by 24 kilograms of standard coal per ton of steel, and the annual energy saving will be 360,000 tons of standard coal. Coal.” Liu Daide summarized Zhanjiang Iron and Steel’s energy-saving work since 2017.
Among them, Zhanjiang Iron and Steel has saved a total of 90,000 tons of standard coal by optimizing production operations, reducing interface temperature drop, and improving process energy efficiency; by optimizing the energy system, reducing emissions and losses, and improving energy conversion efficiency, a total of 90,000 tons of standard coal has been saved ; Through the implementation of 38 energy-saving technological transformation projects, the annual energy saving is about 180,000 tons of standard coal.
Liu Daide introduced that in the past five years, in order to pursue the ultimate energy efficiency, Zhanjiang Iron and Steel has adopted about 116 internationally advanced energy-saving and environmental protection technologies, invested 720 yuan per ton of steel, and adopted a series of work measures at the same time.
Improve processing conversion efficiency. One is to reduce energy medium loss through system optimization. In 2022, Zhanjiang Iron and Steel’s BFG (blast furnace gas) emission rate will decrease by 7.6% compared with 2017, reducing gas emission by 1.39 billion standard cubic meters year-on-year; the loss rate of low-pressure steam in 2022 will decrease by 28% compared with 2019, reducing steam loss by 10.1% year-on-year tons. The second is to improve the efficiency of residual energy recovery and collect all receivables. In 2022, Zhanjiang Iron and Steel’s steam recovery volume per ton of steel and LDG recovery volume will increase by 33.0% and 24.7% respectively compared with 2017, with an increase of 1.74 million tons of steam recovery volume and 275 million standard cubic meters of LDG recovery volume year-on-year. The third is to improve the energy efficiency of seawater desalination and compressed air systems. In 2022, Zhanjiang Iron and Steel’s desalination system steam power consumption and compressed air system power consumption will decrease by 4% and 19.5% respectively compared with 2017, with a year-on-year reduction of steam consumption of 24,000 tons and an annual reduction of electricity consumption of 85.08 million kWh. The fourth is to improve the energy efficiency of the power generation system. In 2022, the coal consumption of the coal power system for power supply will decrease by 3 grams of standard coal/kWh compared with 2017, and the coal consumption will be reduced by 16,296 tons of thermal coal year-on-year; the CDQ waste heat power generation rate will increase by 24kWh/ton of coke compared with 2017, and the power generation will increase by 62.98 million kWh year-on-year . The fifth is to increase the amount of waste water recycling and reduce water consumption per ton of steel. “Zhanjiang Iron and Steel adopts the whole system management and technological innovation of ‘extract-system-supply-use-return’, the recycling of wastewater increases year by year, and the water consumption per ton of steel decreases year by year. In 2022, it will decrease by 1.35 tons per ton of steel compared with 2017, and the annual water saving will be 1720. Ten thousand tons.” Liu Dade said.
Optimized to improve interface energy efficiency. On the one hand, Zhanjiang Iron and Steel has increased the turnover rate of torpedo tank cars (TPCs) and reduced the temperature drop of molten iron. In 2022, the TPC turnover rate will increase by 1.3 times per day compared with 2017, and the temperature drop of molten iron will be 9°C higher than that in 2017. In particular, in November 2022, it will achieve a monthly “breaking 100” for the first time, reaching the historical best level of 98.9°C. On the other hand, the ratio of hot delivery and hot charging in the rolling process will be increased. In 2022, the hot charging and hot delivery rate (above 400°C) of the hot rolling process will increase by 37 percentage points compared with 2017, and the fuel consumption will decrease by 11%; Percentage points, the fuel consumption is reduced by 20%. “Both of these two items have reached the best level in history.” Liu Dade emphasized.
Vigorously promote smart energy. The first is to develop a smart energy management system to realize four transformations in energy management (from result to process, from index to cost, from qualitative to quantitative, and from business to all employees). Zhanjiang Iron and Steel has developed the first smart energy management system in China based on “three streams and one state” (energy flow, manufacturing flow, value flow, and equipment status), and has developed 451 functions including daily energy consumption control analysis, cost analysis, and carbon emission analysis. Page development and application to realize the four transformations of energy management. At the same time, through the research and development of a smart energy online scheduling decision-making platform, the online prediction and precise regulation of the energy system can be realized. The second is to develop and apply a smart water control system to realize the four unifications of water system management and control in the whole plant (unified production collaboration platform, open application platform, data platform, and hardware platform). “Since it was put into operation in 2019, the water consumption per ton of steel has dropped by 40%.” Liu Daide pointed out.
Apply energy-saving technologies. Zhanjiang Iron and Steel has increased its investment. Since 2017, it has implemented 38 energy-saving technological transformations, including the improvement of the comprehensive efficiency of waste heat resources in scorched areas, achieving an annual energy saving of 180,000 tons of standard coal. Among them, through the utilization of waste heat resources and the improvement of equipment energy efficiency, energy saving was achieved by 45% and 34%, respectively, with a contribution rate of nearly 80%.
The processes of coking, sintering and converter have reached the benchmark value of energy efficiency
“Currently, the coking, sintering, and converter processes of Zhanjiang Iron and Steel have all reached the benchmark value of energy efficiency, and the energy consumption of the steel rolling process is better than the pilot value of Baosteel.” Liu Daide said.
Liu Daide said that in order to promote energy efficiency to reach the benchmark, Zhanjiang Iron and Steel has carried out the action of systematically promoting the smelting process to “reach the benchmark” and the steel rolling process to “create a pilot”. Zhanjiang Iron and Steel incorporated energy efficiency benchmarking into the promotion system of the Carbon Neutral Committee, planned and implemented energy efficiency benchmarking labor competitions, and at the same time carried out “benchmarking” and “creating pilot” case releases to create a good promotion atmosphere in the enterprise.
In each process, Zhanjiang Iron and Steel also exerted more efforts, and the effect was remarkable. Through measures such as optimizing coal blending to stabilize the coking rate, increasing the recovery rate of CDQ steam, and stabilizing the recovery rate of coke oven gas and chemical products, the energy consumption of the coking process (104kgce/t coke) has been stably up to the benchmark, which is 6kgce/t coke lower than the benchmark value ;By adhering to advanced measures such as low-carbon thick material layer sintering and increasing sintering waste heat recovery steam, the energy consumption of the sintering process (42.4kgce/t ore) is stable and advanced, which is 2.6kgce/t ore lower than the benchmark value; by adjusting the converter Gas recovery parameters, interspersed dedusting fan speed reduction and power saving and other measures to reach the benchmark in 2022, the energy consumption of the converter process (-31.4kgce/t steel) stably reached the benchmark, 1.1kgce/t steel lower than the benchmark value. At the same time, Zhanjiang Iron and Steel has taken measures such as increasing the rate of hot charging and hot delivery, optimizing the heating process of variety steel, and applying low-temperature alkali cleaning in the cleaning section of the annealing unit, so that the energy consumption of the hot rolling process is 39.4kgce/t, which is better than Baosteel’s 43.0kgce/t The energy consumption of acid rolling process and continuous annealing process is 15.2kgce/t and 45.6kgce/t respectively, which is better than Baosteel’s 16.0kgce/t and 47.0kgce/t.
“The energy consumption of the blast furnace process has not reached the benchmark value, and it still needs to be tackled.” Liu Daide emphasized that in 2022, the proportion of economic furnace materials used in blast furnaces will increase, and the coke ratio and fuel ratio will deteriorate significantly; There is still a gap of 10kgce/t iron.
“According to the development plan of Zhanjiang Iron and Steel, by 2025, the coke oven process and the converter process will further improve the energy efficiency level on the basis of reaching the benchmark, reaching the energy consumption levels of 102kgce/t coke and -32.0kgce/t steel respectively. Blast furnace process Through the research of energy-saving technologies such as the automatic firing model of hot blast stoves and the recovery of waste heat from blast furnace slag, we will strive to achieve stable energy consumption and reach the benchmark value.” Liu Daide said.
Multi-pronged approach to build energy efficiency benchmark demonstration
Liu Daide said that during the “14th Five-Year Plan” period, Zhanjiang Iron and Steel will earnestly implement the requirements of Baowu Group, with the goal of extreme energy efficiency, quickly achieve benchmark energy consumption, and further build Zhanjiang Iron and Steel into a benchmark demonstration of energy efficiency for green, low-carbon and high-quality development. The goal of “the highest energy efficiency, the lowest emission, the best environment, the harmonious society and enterprises, and the beautiful Zhansteel with international leading level” is firmly moving forward.
One is the pursuit of extreme energy efficiency. In 2022, Zhanjiang Iron and Steel carried out training for energy managers and on-site energy-saving diagnosis, allowing people who can hear the “sound of guns” to manage on-site energy and lay a solid foundation for promoting extreme energy efficiency. “In the future, Zhanjiang Iron and Steel will steadily promote the ’14th Five-Year’ energy efficiency improvement plan.” Liu Daide introduced that Zhanjiang Iron and Steel’s “14th Five-Year” energy efficiency improvement plan (including 256 energy-saving projects, including 170 energy-saving management measures and 86 energy-saving transformation projects ) The planned total investment is about 1.27 billion yuan, the estimated energy saving is about 260,000 tons of standard coal per year, and the reduction of carbon dioxide emissions is about 680,000 tons per year. From 2021 to 2022, 25 energy-saving renovation projects have been established, with a cumulative energy saving of 105,000 tons of standard coal per year.
The second is to accelerate the development of green energy. “From 2021 to 2025, Zhanjiang Iron and Steel plans to build a new plant with a new energy installed capacity of 200 megawatts.” Liu Daide said. According to reports, the first phase has been connected to the grid, with an installed capacity of 48 megawatts and an annual power generation of 57 million kWh; the second phase is in the construction stage and is planned to be put into operation by the end of this year, with an installed capacity of 47 megawatts and an annual power generation of 53 million kWh; the third phase It is in the planning stage, and it is planned to complete a total of 150 MW of photovoltaic installed capacity and 50 MW of wind power by 2025.
The third is to implement the construction of low-carbon metallurgical projects. “Zhanjiang Iron and Steel will build the country’s first 1 million-ton hydrogen-based shaft furnace system project in the future, and further carry out the research and promotion of the ‘hydrogen-based shaft furnace + electric furnace’ short-process zero-carbon steel demonstration line project to achieve a comprehensive energy consumption per ton of steel that is higher than the traditional one. The whole process has dropped by 38%.” Liu Daide said that he will strive to achieve stable production of the shaft furnace by 2025, reaching an annual output of 1 million tons, and realizing flexible switching of production under different working conditions.