In the article, it is mainly introduced the hot-dip galvanized green steel product BTRC20 for home appliances is successfully developed by adding over 20% scrap steel as well as utilizing existing process equipment of smelting, hot rolling, cold rolling and galvanizing of Baotou Steel. Its yield strength is 212~279 MPa, tensile strength is 331~368 MPa and elongation is 31.0%~50.5%. Various indexes of developed hot-dip galvanized steel sheet BTRC20 for high-end home appliances such as mechanical properties, corrosion resistance and coating performance could all meet the technical standard of delivery. It is widely used for manufacturing the out board of such high-end home appliances and office equipment as computer, server, audio equipment and automatic office system, which is with stable bulk supply capacity.

The pure water generally prepared with industrial raw water by adopting the process of membrane treatment+mixed bed water treatment is used for boiler feedwater of coke dry quenching in coking industry. There is repeatability for membrane treatment process in advanced treatment of phenol cyanogen wastewater and preparation process of boiler feedwater, so demineralized water can be replaced by advanced treatment for contributing water to reduce the operating costs of enterprises. It is preliminarily determined to be with feasibility through studying the characters of water quality and water quantity of effluent from demineralized water system of boiler feedwater and reuse water of phenol cyanogen wastewater. The industrial test results showed that the indexes of effluent could satisfy the operating requirements of boiler for coke dry quenching, quantity of fresh water used was reduced by 90% and disposing costs of demineralized water was reduced by 15%~20% with the scheme, which could provide the technical support for “zero discharge” of phenol cyanogen wastewater.

The Zn-Al-Mg coated steel sheet is widely used in such industrial fields as automobile and construction due to its excellent corrosion resistance. Its stamping performance, the key factor affecting product quality and production efficiency, is always research hotspot in the industry. In the paper, it is summarized the research status of stamping performance for Zn-Al-Mg coated steel sheet including its research background, development sequence, influencing factors, research methods as well as problems and challenges faced. Early researches are the preliminary exploration of stamping performance and researches are gradually deepened with technological progress, which include such aspects as composition, microstructure, thickness of coating and mechanical properties of steel sheet as well as experimental testing and numerical simulation technique become the main research methods. At present, there have been many break through points in the research of stamping performance for Zn-Al-Mg coated steel sheet, but challenges are still faced in terms of performance balance and evaluation of complex working conditions. In the future, the applications of new technologies and deepening of multifactor coupling research are expected to promote further development of this product.

The experimental study on discarding tailings in advance is carried out for raw ore to be ground and ore discharged by primary ball mill of a mine with the processes of dry-type and wet-type discarding tailings in advance based on studying process mineralogy of low grade iron ore in the mine as well as size composition of raw ore to be ground and ore discharged by primary ball mill in the existing process. The experiment results showed that the tailings with productivity of 28.27% and content of magnetic iron of 0.44% could be discarded for raw ore to be ground with dry-type discarding tailings in advance; the tailings with productivity of 33.44% and content of magnetic iron of 0.49% could be discarded for raw ore to be ground with wet-type discarding tailings in advance; the tailings with productivity of 41.39% and content of magnetic iron of 0.36% could be discarded for ore discharged by primary ball mill with wet-type discarding tailings in advance.

The alloying before VD (vacuum degassing) process is developed by optimizing slag formation process and deoxidation system of LF (ladle furnace) as well as the alloying operation after VD is changed to before VD process aiming at such problems as fluctuation of composition of molten steel, excessive inclusions and long production time caused by lagged alloying operation after VD in the vacuum treatment process of aluminium killed steel. The application practices showed that the holding time of white slag was extended to 15~20 min, total oxygen content of molten steel after VD was reduced to 0.001 2%~0.002 0%, rating of fine B class inclusion (Al₂O₃) was decreased from grade 2.0 to grade 1.0 and power consumption of refining was reduced to 48.51 kWh/t.

In this paper, the effects of optimizing structure of coal as fired on metallurgical performances of coke are systematically studied by adding XN fat coal and SX coking coal S1.3 based on the coal as fired of coke oven in a company aiming at the strict requirements of coke quality for blast furnace ironmaking. The experimental results showed that the coke strength after reaction (CSR) and mechanical strength (M₄₀) could be significantly improved with both scheme 1 and 2, thereinto, CSR was increased by 7.7 percentage point, M₄₀ was increased by 6.4 percentage point as well as proportion of large and medium coke size was increased by 7.64 percentage point with scheme 2 compared with those of basic scheme. This study provides theoretical and practical basis for industrial coal blending optimization.

In order to effectively break through the bottleneck problem of capacity of sinter, upgrading and transformation of existing 265 m² sintering machine are implemented. The capacity of sintering machine is significantly enhanced through adopting a series of measures including widening trolley, upgrading main exhauster and optimizing pelletizing system. After the transformation, average daily output of sinter is increased by 1 013 t and utilization coefficient of sintering machine is improved from 1.332 t/ (m²·h) to 1.484 t/ (m²·h); drum index of sinter is increased by 0.3 percentage point and its size composition is improved; solid fuel consumption of sintering is decreased by 1.19 kg/t and electricity consumption is decreased by 4.97 kWh/t so that the energy medium and manufacturing costs are significantly reduced.

In this paper, YQ450NQR1 zed beam is taken as the research object and trace rare earth elements are added in smelting process to improve its corrosion resistance. The influences of trace rare earth elements on corrosion resistance of YQ450NQR1 zed beam are studied by phase detection, alternate immersion accelerated corrosion test and electrochemical analysis of rust layer. The study results showed that the grain could be refined, stable α-FeOOH could be promoted to be generated so that rust layer was more compact by adding trace rare earth elements into YQ450NQR1 zed beam. As a result, the self-corrosion potential of material is improved and transfer resistance of charge is increased so that the corrosion resistance of material is improved.

The structural steel is widely used in such industries as automobile, construction and photovoltaics due to its good comprehensive properties. In this paper, the effects of different microalloyed compositions and metallurgical process routes on microstructure and properties of 350 MPa grade products are studied and determined based on the differences of CSP (compact strip production) and conventional hot continuous rolling aiming at the request for utilization of photovoltaic products while considering effective productions of production line. The study results indicated that the properties of products manufactured with different process routes could all meet standard requirements. Although the contents of strengthening elements (carbon, manganese and titanium) in products with CSP production line are lower than those in products with conventional hot continuous rolling production line, the yield strengths of products manufactured with the two production lines are approximate, which are 400~460 MPa.

The method of testing recrystallization temperature for cold rolled sheet with thermal simulated test machine in laboratory is introduced in this paper. The thermal simulation experiment schemes with a series of annealing temperatures and time are designed combining with on-site production conditions. The recrystallization temperature of test steel is obtained through thermal simulation experiments of SPFC390 cold rolled sheet at a series of temperatures, hardness test and microstructure analysis. The recrystal activation energy and coefficients are obtained by calculation as well as the relational model of recrystallization temperature and annealing time for test steel is established, which could provide the basis for formulating or optimizing annealing process on site.