Waste heat recovery from hot steel slag on the production line:Numerical simulation,validation and industrial test

Waste heat recovery from hot steel slag was determined in a granular bed through the combination of numerical simulation and an industrial test method.First,the effective thermal conductivity of the granular bed was calculated.Then,the unsteady-state model was used to simulate the heat recovery under three different flow fields(O-type,S-type,and nonshielding type(Nontype)).Second,the simulation results were validated by in-situ industrial experiments.The two methods confirmed that the heat recovery efficiencies of the flow fields from high to low followed the order of Nontype,S-type,and O-type.Finally,heat recovery was carried out under the Nontype flow field in an industrial test.The heat recovery efficiency increased from~76%and~78%to~81%when the steel slag thickness decreased from 400 and 300 to 200 mm,corresponding to reductions in the steel slag mass from 3.96 and 2.97 to 1.98 t with a blower air volume of 14687 m^(3)/h.Therefore,the research results showed that numerical simulation can not only guide experiments on waste heat recovery but also optimize the flow field.Most importantly,the method proposed in this paper has achieved higher waste heat recovery from hot steel slag in industrial scale.

Prospects for green steelmaking technology with low carbon emissions in China

The steel industry is a major source of CO_(2) emissions,and thus,the mitigation of carbon emissions is the most pressing challenge in this sector.In this paper,international environmental governance in the steel industry is reviewed,and the current state of development of low-carbon technologies is discussed.Additionally,low-carbon pathways for the steel industry at the current time are proposed,emphasizing prevention and treatment strategies.Furthermore,the prospects of low-carbon technologies are explored from the perspective of transitioning the energy structure to a“carbon-electricity-hydrogen”relationship.Overall,steel enterprises should adopt hydrogen-rich metallurgical technologies that are compatible with current needs and process flows in the short term,based on the carbon substitution with hydrogen(prevention)and the CCU(CO_(2) capture and utilization)concepts(treatment).Additionally,the capture and utilization of CO_(2) for steelmaking,which can assist in achieving short-term emission reduction targets but is not a long-term solution,is discussed.In conclusion,in the long term,the carbon metallurgical process should be gradually supplanted by a hydrogen-electric synergistic approach,thus transforming the energy structure of existing steelmaking processes and attaining near-zero carbon emission steelmaking technology.

Eco-transformation of steel industry in China: from the perspective of industrial ecology and circular economy

Recently the behavior of human has resulted in the deterioration of global ecological environment, and global warming and environmental pollution have caused the occurrence of extreme events frequently. If we repeat the reckless environmental overkill, civilization will enter a vicious circle of decline and lose even the strength and vitality to live in harmony with the environment. At present, China is in a special period of rapid economic development. Some enterprises focus on short-term profits and don't formulate long-term strategies. For example, with the rapid expansion of the steel industry, some serious problems have emerged. Based on principles of industrial ecology and the concept of circular economy, to develop a new development model, taking a new road to industrialization is very necessary. Re-examining the current steel enterprises, this paper proposes the new methods of the integration of material, energy integration, water system integration and sharing of information and facilities. Through ecologicalization of technology, system, and industrial structure and product structure adjustment, the eco-transformation of the modern steel industry will be gradually achieved in China.

Highlights of Recent Advances in Refractories for Iron and Steel Industry in China

Recently procured outstanding achievements in iron and steel industry in China are presented by data or facts in steel output, energy consumption, technical and economical indicators and advanced technologies that are being adopted. The latest achievements in refractonries for this biggest user industry are reviewed, covering new refractories for CDQ coke oven, BF hearth, AOD Lining, long life tundish, SEN for clean steel making and regenerative reheating furnace . The reciprocal relationship is obvious that the rapid development of iron and steel industry has given an impetus to the advance of refractories industry, which in return has contributed greatly to the former.

An Optimized Oxygen System Scheduling With Electricity Cost Consideration in Steel Industry

As an essential energy resource in steel industry,oxygen is widely utilized in many production procedures.With different demands of the oxygen amount,a gap between the generation and consumption always occurs.Therefore,its related optimization and scheduling work along with the electricity cost to fill the gap has a great impact on daily production and efficient energy utilization in steel plant.Considering an oxygen system in a steel plant in China,a nonlinear programming model for oxygen system scheduling is proposed in this study,which concerns not only the practical characteristics of the energy pipeline network,but also the electricity cost acquired by a fitting regression modeling between the load of air separation units(ASU)and its corresponding electricity consumption.A set of constraints is formulated for restricting the practical adjusting capacity and filling the imbalance gap of oxygen.To solve the proposed scheduling model with electricity cost consideration,a particle swarm optimization(PSO)algorithm is then adopted.To verify the effectiveness of the proposed approach,a large number of experiments employing the real data from this plant are carried out,both for the fitting regression and the scheduling optimization phases.And the results demonstrate that such a practice-based solution successfully resolves the oxygen scheduling problem and simultaneously minimizes the electricity cost,which will be beneficial for the enterprise.

Emission Mitigation of CO_2 in Steel Industry: Current Status and Future Scenarios

The sustainable development against global warming is a challenge faced by societies at global level. For steel industry; the pressure of reducing CO2 emission is likely to last many years. During the past decades, the CO2 emission per ton steel has been reduced mainly due to the improvement of energy efficiency. Entering the 21st century, the steel manufacturing route must have three functions, namely, production of high performance steel products, conversion of energy, and treatment of waste. In the near future, it is expected that existing BF-BOF and EAF routes will be improved, in order to produce high performance steels, increase the use of scrap, and integrate steel industry with other industries for mitigating CO2 emission. In the long term, using carbon-free energy, reducing agents, and storing CO2 securely or converting CO2 into a harmless substance can be presumed for tremendous reduction in CO2 emission.

Clean Production of Steel and Refractories in China's Steel Industry

The paper describes the importance of clean production of steel and the relationships amongst sustaining development of steel industry, environment protection and the role of refractories in the clean production of steel. The main achievements and main shortcomings in the clean production of China ' s steel industry have been reviewed together with the introduction of the policy supporting system and the future development of clean production in China ' s steel industry.

Techniques for Treating Sulphuric Acid Pickling Waste Liquid of Steel Industry

Pickling waste liquid of the steel industry is included in National Hazardous Wastes Catalogue because of its high corrosion and large discharge. The techniques for treating pickling waste liquid （ H2SO4 ） in steel industry is summarized. The advantages, disadvantages and applied ranges of all kinds of control technologies are comparatively analysed. The research trends of techniques for treating pickling waste liquid （ H2SO4 ） are the resource reclamation technologies in future which is pointed out in the paper.

SUMMARY OF CHINA-MADE X-RAY THICKNESS GAUGES FOR STEEL INDUSTRIES

There are two kinds of China- made X- ray thickness gaugemeters i.e. dual beam- dual detector system and single beam- single detector system- SM series, the latter is used dominantly in Chinese steel industries. The performance comparison between domestic and foreign instruments as well as its developments and applications is presented in this paper.

THE STEEL INDUSTRY IN ARAB COUNTRIES

A brief introduction to Arab countries, in respect of their locations, populations, areas and mineral resources, was given. The development of steel industry in Am6 countries in last two decades was staled as a whole. And the steel industries in Egypt, Qatar, Saudi Arabia, United Arch Emirates (UAE), Morocco, Libya, Joanal, Tunisia, Syria, Iraq, Algeria and Bahrain were analyzed separately. Some development problems faced by Arab steel industry, such as steel market, natural resources, manpower and finance, were pointed out.

Current Situation and Prospect of High Performance Refractories for Iron and Steel Industry in China

The development,physicochemical properties and application effectiveness of new high performance refractory products used in iron and steel industry in recent years are summarizedThe new products include carbon-containing oxides,non-oxides,functional refractories,low cement and ultra-low cement castables etc.It is pointed out that quality of refractory products needs to be improved and high performance varieties be developed.Meanwhile,research should be done on composite materials and composite structures,equipment techniques and optimization control of refractory production should be strengthened as well.

A Glimpse of Iron and Steel Industry of China in Recent Years

The paper briefs the recent development of China＇ s Iron ＆ Steel Industry from the view of a refractorie., worker. Some data and statistics have been revealed in the paper including total output of steel, geological distribution of key steel enterprises, productivity, facilities, technical and economical indices as well as technical advance achieved in. the last ten years. Structural adjustment and consolidation occurred in China＇s Iron ＆ Steel industy has also been described. The views on how much steel is demanded in China in the near future advanced by a steel expert has been accepted as the conclusion of the paper.

Current situation of carbon emissions and countermeasures in China's ironmaking industry

The iron and steel industry(ISI) involves high energy consumption and high pollution. ISI in China, a leading country in the ISI,consumed 15% of the country’s total energy and produced more than 50% of the global ISI’s carbon emissions. Therefore, in the context of global low-carbon economy and emission reduction requirements, low-carbon smelting technology in the ISI has attracted increasingly more attention in China. This review summarizes the current status of carbon emissions and energy consumption in China’s ISI and discusses the development status and prospects of low-carbon ironmaking technology. The main route to effectively reducing carbon emissions is to develop a gas-based direct reduction process and replace sintering with pelletizing, both of which focus on developing pelletizing technology. However,the challenge of pelletizing process development is to obtain high-quality iron concentrates. Consequently, the present paper also summarizes the development status of China’s mineral processing technology, including fine-grained mineral processing technology, magnetization roasting technology, and flotation collector application. This paper aims to provide a theoretical basis for the low-carbon development of China’s ISI in terms of a dressing–smelting combination.

Enhancing mergers and acquisition quality,accelerating technological innovation and achieving the second leap of China's steel industry

Over the past 10 years, China＇s steel industry has made a substantial development in terms of scale, and has finally become a steel giant in the world. In the upcoming 10 years, fundamental changes will be made with the economic growth in China. Against this background, China＇ s steel industry will shift from a rapid development to a slow but sound development. In order to fulfill the second leap of China＇s steel industry, based on its current developing status and characteristics, and from the perspective of both national and corporate development, mergers and acquisition are both effective ways to raise the quality of the existing stock of asset in the steel industry, while technological innovation is the solid foundation for its second leap.

The challenging conditions China's steel industry has to face and the possible way out

The challenging conditions to China's steel industry currently are:insufficiency of natural resources, namely iron ore and coking coal,overcapacity of existing facilities,overconsumption of energy and heavy impact on global environment.The healthy development of China's steel industry depends on how we could deal with these challenges.

Carbon dioxide emissions reduction technology and its application prospects in the steel industry

Fossil-fuel burning greenhouse gas induced global warming has been recognized as global environmental problems,reduce and ultimately control the energy production in the use of CO_2 emissions, global energy production will be a major challenge.As a highly intensive materials and energy,iron and steel enterprises,need to be invested to produce one ton of steel about two tons of material and 0.7 t of standard coal energy,and while producing two tons of CO_2.Therefore,reducing CO_2 emissions from iron and steel industry has become the focus of the global steel industry.This paper describes an integrated domestic and international measures to control carbon dioxide emissions research progress and future technology trends, with emphasis on the domestic steel industry emissions of carbon dioxide status of technology development and industrialization of implementation of the proposed on this basis,including dry quenching technology, gas,power generation,coal moisture control technology,blast furnace injection plastics technology,the use of coking process for treating municipal waste plastics technology,sintering heat generation,low pressure saturated steam for power generation,metallurgical slag heat recovery technology,coke oven gas hydrogen technology and the other key technologies energy saving technologies,including the development,promotion and popularization of the steel industry in China will be the CO_2 emission reduction technology direction and focus.At this stage,the Chinese steel industry can be improved the energy efficiency and recycling of waste heat and energy,reduce unit GDP,CO_2 emissions;but in the long run,should increase CO_2 capture and storage on the input of technology can possible effective control of the adverse effects of CO_2 emissions.

Alloy steel pipes and furnace tubes for petrochemical industry

The equipments and pipes serving at high temperature and pressure and the presence of hydrogen in the petrochemical industry are usually made of Cr-Mo steels.Cr9Mo pipes replacing Cr5Mo are widely used in many parts of/with high-sulfur crude oil refining equipment to meet the more demanding high temperature anticorrosion and oxidation resistance requirements.The mechanical property,creep rupture property and high temperature oxidation-resistant property of domestic Cr9Mo steel are at the same level as the similar foreign products.Three years applications indicate that domestic Cr9Mo steel can fully meet the service requirements of petrochemical industries.Finally,this paper presents the material selection guidelines for the key oil refining devices processing of low sulfur/high acid crude oil.