Effect of Electrolyzed Alkaline-Reduced Water on the Early Strength Development of Cement Mortar Using Blast Furnace Slag

This study evaluated the use of electrolyzed alkaline-reduced water instead of an alkaline activator for the production of a strong cement matrix with a large blast furnace slag replacement ratio. The flexural and compressive strength measurements, X-ray diffraction analysis, and scanning electron microscopy images of the cement matrices produced using electrolyzed alkaline-reduced water and regular tap water, and with blast furnace slag replacement ratios of 30 and 50% were compared to a normal cement matrix. The cement matrix produced using electrolyzed alkaline-reduced water and blast furnace slag exhibited an improved early age strength, where hydrate formation increased on the particle surface. The cement matrix produced using electrolyzed alkaline-reduced water exhibited a high strength development rate of over 90% of ordinary Portland cement (OPC) in BFS30. Therefore, the use of electrolyzed alkaline-reduced water in the place of an alkaline activator allowed for the formation of a very strong cement matrix in the early stages of aging when a large blast furnace slag replacement ratio was used.

Development and production of large blast furnaces from 2015 to 2016 in China

This article has reviewed the production status, total reductant consumption, raw materials and operation principle indexes of large blast furnaces in China from 2015 to 2016. The developing actuality of Chinese large BFs has been quantitatively analyzed and the existing problems have been proposed clearly. Based on that, maintaining production stable, enhancing the quality of raw materials and improving the operation principles are suggested. Large BFs take advantages of high-quality hot metal, energy saving, cost-cutting, high mechanization and automation levels and are sufficient to meet the challenges of economic crisis, environmental pressure and security risk form the future. Thus, the number of large BFs in China will continue to increase in the future.

Study of binders for ecologically safe anhydrous tap-hole clays

Detailed analytical review of the existing tap-hole clays used in the blast furnace production at various metallurgical enterprises is made. It is established that it is necessary to ensure environmental safety when using tap-hole clay. It is clarifi ed that synthetic resins (phenol-formaldehyde and novolac resins) are used instead of harmful coal-tar resin for the production of tap-hole clays. The oxidation of coal-tar resin and pitch occurs up to temperature of 600 °С, which is especially important for large blast furnaces equipped with 2...4 tap-holes.

Development and production of Chinese large blast furnaces in 2019 compared with 2015–2016

By comparing the production indexes of large blast furnaces (BF) in China between the first half of 2019 and 2015–2016, the production status, reductant consumption, raw materials and operation conditions have been reviewed. In the first half of 2019, Chinese large BFs still had made a lot of achievements, but it is also discovered by comparison that not only the raw materials quality but also the large BFs stability have the trend of getting worse, so some work should be done to stop and recover the unfavorable situation. Based on that, the expectations of enhancing the raw materials quality and improving the operation conditions are suggested. Large BFs make great contributions to energy saving, low-carbon, high automatic, environmental protection and economic development, so there will be more large BFs constructed and put into production in China in the future.

Furnace heat prediction and control model and its application to large blast furnace

Blast furnace heat is the key to the blast furnace’s high efficiency and stable operation, and it is difficult to maintain a suitable temperature for large blast furnace operations. When designing the furnace heat prediction and control model, parameters with good reliability and measurability should be chosen to avoid using less accurate parameters and to ensure the accuracy and practicability of the model. This paper presents an effective model for large blast furnace temperature prediction and control. Using thermal equilibrium and the carbon-oxygen balance of the blast furnace’s high-temperature zone, the slag-iron heat index was calculated. Using the relation between the molten iron temperature and slag-iron heat index, the furnace heat parameter can be calculated while production conditions are changed,which can guide furnace heat control.