SDM: Make contributions to the innovation of green and low-carbon iron&steel technology
All for the client
The target about peak carbon dioxide emissions and the vision of carbon neutrality are the major strategic decisions made by the CPC Central Committee and the State Council to coordinate the international and domestic situations, which have far-reaching impact and significance. The carbon dioxide emissions of steel industry account for about 15% of the total emissions of the country. It is the manufacturing industry with the largest emissions. The steel enterprise is an important responsible subject to implement the carbon dioxide emission reduction goal.
Shandong Province Metallurgical Engineering Co., Ltd. (hereinafter referred to as "SDM") vigorously promotes technological innovation and integration, and is in the forefront of green and low-carbon intelligent metallurgy and creating high-quality ecosphere for iron&steel industry. SDM continues to tackle key problems in green and low-carbon featured technologies, strives to build a green and low-carbon development pattern for iron&steel industry in the new era, and is a demonstrator and leader in promoting the green and low-carbon transformation and development of the industry.
1. Focus on green iron&steel, and reduce pollution and carbon dioxide emissions in the whole process
It is the unique advantage of SDM to have all the design disciplines of iron and steel metallurgy and advanced engineering technology in the whole process. With dynamic and accurate process design, it promotes the efficient linkage of iron and steel metallurgy processes, reduces energy consumption and forms a synergistic effect for the reduction of carbon dioxide emissions .
1.1 New-type, green, intelligent and large-volume coke oven equipment technology
The large-volume, green and intelligent coke oven jointly designed and developed by SDM and Italian Paul Wurth, which adopts world-class processes and technologies, is one of the advanced representatives of the development of large-volume, green and intelligent coke ovens, and has reached the domestic and international advanced level in terms of coke oven proper, machinery, process equipment, automation and environmental protection.
The 7.3m large-volume, green, intelligent coke oven (Figure 2) of Rizhao Iron and Steel High Quality Product Base (Figure 1) contracted by SDM has a coking heat consumption of 2350kJ/kg wet coal (7% H20), which is superior to domestic top-class ovens. The annual emission reduction is 104,000 tons of CO2, 157.68 tons of dust, 473.04 tons of SO2 and 2,128.68 tons of NOX. In addition, it also has the advantages of significantly reducing iron-making costs and pollutant emissions, etc., which has demonstration effect and extensive promotion value to promote China's coking technology progress, ultra-low emissions and clean production, and improve coking technology and equipment.
The technology of new-type, green, intelligent and large-volume coke oven equipment has won the second prize of the Metallurgical Science and Technology Award of CISA and CSM. Its distinctive advantages include: low consumption coking technology, asymmetric flue technology of coke oven, single carbonization chamber pressure regulation and control technology, coal moisture regulation technology, CDQ and waste heat power generation technology.
1.2 Large volume, high efficiency and low carbon emission of BF
Large and efficient blast furnace is characterized by stability, low fuel ratio, low process energy consumption and high production efficiency, which is of great significance for low-carbon production, reducing environmental load and realizing ecological development. The 5100m3 super large BF in Rizhao Iron and Steel High Quality Product Base (Figure 3), which was designed and contracted by SDM, has a utilization factor of 2.16t/m3 · d, an average coke ratio of 320kg per ton of iron and a coal ratio of 165kg, reducing fuel consumption by 33kg compared with that of 3000m3 BF. Comprehensively considering TRT power generation capacity, zero emission of top gas, etc., the emission reduction of CO2 per ton of iron is 105.5kg, and the annual emission reduction of CO2 is more than 850,000 tons.
Featured and advantageous technologies of super large BF include: comprehensive technology of long service life of BF, comprehensive technology of full dry purification of BF gas, modern cast house technology, zero emission process and intelligent recovery technology of top gas, "clean" drum slag treatment technology, and fully automatic precise coal injection technology, etc.
1.3 Technology of top combustion HBS for super large BF
SDM is the only engineering company in China that has the performance and capability of general contracting of top combustion HBS supporting BF of more than 4000m3. The new generation green intelligent top combustion HBS technology with fully independent intellectual property rights has occupied more than 40% of the domestic market share, and has expanded to international markets such as Asia, Europe, South America and Africa. It has the characteristics of high blast temperature, long service life and environmental friendliness. The air temperature of pure burning BF gas reaches 1250 ℃, and the air temperature of external combustion furnace system reaches 1300 ℃. The BF gas consumption is reduced by 80Nm3 and CO2 emission is reduced by 68.56kg per ton of iron.
The characteristic advantages of the top combustion HBS include: high efficiency and low nitrogen combustion technology, burner insulation layer technology, hot blast piping arrangement, full-automatic heating control system, and HBS flue gas denitration technology.
1.4 Integrated technology of efficient, low-consumption and intelligent bar production line
The single line new-type bar production line with an annual output of 2 million tons designed and developed by SDM in the 1# and 2# bar plants of new area of Shiheng Special Steel has the remarkable characteristics of advanced technology, intelligent efficiency, high yield and low consumption, which is of great significance for low energy consumption and low-carbon production. The technology of production line equipment has reached the leading domestic and international level.
The actual yield index reaches 98.5%, which is 0.5% higher than the domestic advanced bar production line; the gas consumption per ton of steel in the production line is lower than 0.4GJ, which is 0.3GJ/ton less than that in the domestic advanced bar production line; the power consumption index per ton of steel in the production line is lower than 10kWh, which is 10kWh/ton less than that in the domestic advanced bar production line. Compared with the domestic advanced bar production line, the single line can reduce CO2 emissions by 60,000 tons per year.
The advantages of efficient, low consumption and intelligent bar production line include: closed-loop controlled rolling and cooling technology, high temperature hot conveying and hot charging technology, double regenerative walking type reheating furnace technology, economical and effective long billet production technology, intelligent monitoring and control technology for temperature field of the whole line, development technology of multi-line slitting pass, full scale production technology, cooling bed waste heat recovery technology, intelligent enhanced collection and integration technology, intelligent equipment and intelligent robot technology Automatic removal and restructuring technology of short-gauge materials, automatic monitoring technology for key equipment, etc.
1.5 Flexible iron&steel interface coordination technology
This technology takes the automobile transportation of molten iron as the core, scientifically solves many problems of molten iron transportation between large blast furnaces and converters, and obtains many industry initiatives. It realizes the goal of "five savings" of saving land, investment, staffing, production and operation costs, and energy in the general layout.
The average temperature drop of molten iron from tapping to converter molten iron charging is about 58 ℃, which is significantly improved compared with the temperature drop of 100-180 ℃ in the traditional transportation process. Only for this item, the CO2 emission reduction per ton of steel is 35.8kg.
1.6 Activated calcium desulfurization technology
The SO2 in the flue gas is removed by injecting active calcium instead of soda desulfurizer, and the dust generated is removed by bag filter to make the flue gas emission meet the standard. In this way, 1.375 tons of CO2 emission can be reduced in the process of removing 1 ton of SO2.
1.7 High efficiency utilization technology of waste heat and energy
SDM has mastered dozens of energy-saving and emission reduction featured technologies of iron and steel enterprises with independent intellectual property rights, such as efficient power generation by gas, power generation by CDQ waste heat, power generation by sintering waste heat, recovery and power generation of converter waste heat and energy, and converter waste heat and energy recovery and power generation, as well as HIsmelt smelting gas waste heat recovery technology, gas distributed energy technology, large-volume BF blast and gas TRT residual pressure power generation, and industrial low-quality waste heat heating. The diversified design and mature general contracting performance of SDM include 7MW electric furnace low pressure saturated steam power generation, 65MW gas ultra-high temperature ultra-high pressure parameter power generation, CCPP gas&steam combined power generation, 5000m3 BF blower and gas TRT, and million square meters type low-temperature waste heat heating project. The performance indicators have reached the international advanced level. In the project of 65MW gas power generation with ultra-high temperature and ultra-high pressure parameters, the annual CO2 emissions could be reduced by more than 250,000 tons.
2. Improve low carbon production in iron&steel plants with intelligent technology
Under the background of realizing the government's goal of "reaching peak carbon dioxide emissions and carbon neutrality", the intelligent manufacturing of steel industry has entered a new mode of green, low-carbon and intelligent. "Intelligent sensing, intelligent analysis and intelligent control" are the core contents of realizing intelligent manufacturing. On the basis of stable and reliable measurement, detection, transmission and control, SDM has developed a series of advanced and practical intelligent optimization control systems and intelligent management systems to improve the control level and intelligent decision-making ability in production, quality, safety, management, etc., improve the comprehensive labor productivity and resource utilization, reduce product defect rate and operation and maintenance costs, and reduce carbon emissions and pollutant emissions.
2.1 Integrated technology of energy intelligent control center
Establish integrated intelligent energy management and control, including data center, which integrates centralized energy monitoring, unified energy measurement, energy flow balance, energy management and control, energy big data mining, energy performance and other functions to achieve global energy monitoring, energy scheduling, energy forecasting, energy saving and consumption reduction.
Comprehensively improve the operation and coordination efficiency of energy management and control system of iron and steel enterprises, and ultimately reduce the comprehensive energy consumption per ton of steel by more than 2%.
2.2 Intelligent combustion system for HBS&BF
The intelligent combustion system of HBS is an integrated solution to match the combustion control of HBS. It provides a full range of intelligent services for HBS system, such as automatic stove change, intelligent combustion, scheduling of HBS resources, estimation of HBS heat storage, data summary and display. The unit gas consumption per ton of iron decreases by about 30m3, and the CO2 emission per ton of iron decreases by 25.4kg.
2.3 Intelligent coke oven technology
Based on stable and reliable measurement, detection and control, the intelligent coke oven technology realizes the optimal control of the production process through the artificial intelligence software model, and achieves the goal of "three complete, two low and one high" (environmental protection is completely up to standard, energy efficiency is completely optimized, and production is completely controlled; ultra-low emissions of pollutants, energy consumption is greatly reduced; and economic benefits are high).
3. Develop and integrate low carbon and zero carbon metallurgical technology
Develop and integrate cutting-edge low-carbon metallurgy technology and short process technology.
3.1 Oxygen enriched smelting of BF
In order to implement the national "double carbon" action and the CO2 emission reduction target of steel industry, SDM will actively develop integrated low-carbon steel smelting technology. In addition to further improving the smooth running stability of BF, optimizing the operation technology and reducing the fuel consumption of BF, SDM will develop high oxygen enriched natural gas or coke oven gas injection technology for BF before the "14th Five Year Plan" and 2030, which will reduce the carbon emission by more than 50% compared with the traditional blast furnace.
3.2 Non-BF iron-making（HIsmelt）
HIsmelt iron making process is one of the smelting reduction iron making technologies that have achieved industrial production (Figure 4). After more than 30 years of R&D and production practice, the process technology is gradually mature, and its environmental protection advantages are obvious. It is the most green and environmentally friendly, low-emission frontier metallurgical technology in the world, and has a high degree of concern in the international metallurgical field.
HIsmart reduces environmental impact. Through revolutionary process innovation, coking, sintering and pelletizing processes have been eliminated. Compared with traditional metallurgical processes, this technology can reduce CO2 emissions by more than 15%, SO2 emissions by 90% and NOx emissions by 50%, and basically curb the generation of dioxins, tar, phenol and other pollutants.
3.3 Short process technology
The hydrogen based direct reduction-electric furnace short process production line will be developed in the long term to greatly reduce the CO2 emission per ton of steel in the whole process and achieve the goal of carbon neutrality. Sponge iron is produced by hydrogen based direct reduction technology for electric furnace or converter steel making. Through the production of sponge iron, the reducing of hot metal output of BF in the future could be met, and the shortage of scrap steel and the need of smelting high-quality steel could be met.
4. Promote collaborative pollution reduction and carbon emission reduction in upstream and downstream industries
The iron&steel industry and its upstream and downstream industries cooperate to reduce pollution and carbon emission, so as to achieve joint production and carbon emission reduction of iron&steel and chemical industry.
4.1 Explore CO2 collection, storage and utilization technologies
1）Iron&steel waste heat coupling CCUS carbon collection technology. The iron&steel waste heat coupling CCUS ethanolamine method is used for CO2 collection. The collected CO2 is used as the protection gas for coal injection of BF. The use of sintering waste heat coupling CO2 collection technology can reduce the cost of CO2 collection per ton by more than half, about 250 yuan.
2）Cooperate with chemical, petroleum, geological and other industries and companies to carry out demonstration applications of CO2 liquefaction, oil displacement of oilfield and underground storage. In the near future, CO2 removal of converter gas, tail gas of BF&HBS, tail gas of coke oven flue, tail gas of steel rolling heating furnace, etc. will be mainly considered, and they will be used for oil displacement in the oilfield. About 2030, develop and apply the technology of CO2 hydrogenation to produce chemical primary products (methanol, fuel ethanol, etc.). Research and develop the technology of reforming converter gas and coke oven gas to produce synthesis gas for BF injection or gas based shaft furnace direct reduction.
4.2 Deep processing of metallurgical gas to realize high value-added utilization
Iron and steel production generates a large number of by-product gas, mainly including coke oven gas, BF gas and converter gas. The by-product gas accounts for about 30% - 40% of the total energy consumption of enterprise. Its efficient resource utilization is not only conducive to reducing the energy consumption and pollutant emissions of the unit products of iron&steel plant, but also can form an industrial ecological chain with the petrochemical industry, generating new economic and social benefits, which is of great significance.
Coke oven gas contains more hydrogen, while BF gas or converter gas contains more carbon sources. The output products of by-product gas resource utilization mainly include H2, CO, CO2, LNG, methanol, ethanol, ethylene glycol, synthetic ammonia, etc. Take coke oven gas, BF gas or converter gas of iron and steel enterprises as raw materials to produce chemical products such as ethylene glycol and ethanol, so as to realize the application of metallurgical gas with high added-value and low carbon emission.
The raw materials for the production of ethylene glycol are mainly H2, CO and O2. CO is coupled to obtain dimethyl oxalate, and then dimethyl oxalate is hydrogenated to obtain ethylene glycol. The production of ethanol from metallurgical gas mainly includes the following technical routes: biological fermentation for ethanol, synthesis gas-methanol-acetic acid-ethanol (or synthesis gas-methanol-acetic acid-ethyl acetate-ethanol), synthesis gas-methanol-dimethyl ether-methyl acetate-ethanol.
These technologies can make rational utilization of metallurgical gas, avoid environmental pollution caused by direct utilization as fuel, and reduce CO2 emissions. Compared with directly using coke oven gas as fuel, using coke oven gas to produce hydrogen, LNG or other chemical products can increase its added value by nearly one time or more, and can reduce the CO2 emissions of iron&steel enterprises by more than 1%.
4.3 Green electricity and steel coupling
The total photovoltaic power generation capacity of 8MW per 100,000 square meters can be achieved for 25 consecutive years by using the roofs of steel rolling plant, steel making plant, etc. of the steel plant; It can provide 190 million KWH of green power in the whole service life cycle, save about 73,000 tons of standard coal, reduce 50,200 tons of carbon dust, 188,800 tons of CO2 emissions, 5,600 tons of SO2 emissions, and 2,600 tons of NOx emissions.
4.4 The new-type connection point of H-shaped steel truss without gusset plate
The new-type connection point of H-shaped steel truss without gusset plate adopts the connection form similar to that of steel pipe truss with directly welding for intersection without gusset plate, which is simple in structure and convenient in processing, thus reducing the steel consumption and processing difficulty of H-shaped steel truss connection point, and applying it to the lattice column of industrial plant and civil steel structure truss, promoting the wide application of H-shaped steel truss in industrial and civil buildings. Compared with conventional design, this technology can reduce steel consumption by more than 3%.
