In this paper, the successful tapping of 7^# blast furnace of Baotou Steel after long-term blowing down is mainly summarized. It is the first time to use the "embedded observable oxygen lance technology before reblowing of blast furnace" and a set of methods are summarized by taking such measures as the scheme formulation before blowing down, previous preparation and rational use of oxygen lance to guarantee the successful tapping of blast furnace after long-term blowing down, which lays a foundation for rapid recovery of furnace condition.

In this paper, the system component composition, system design, systematic principle and system features of AGC hydraulic control system for wide and thick plate mill of Baotou Steel are introduced and analyzed. Moreover, the troubleshooting and diagnosis of typical faults for the hydraulic control system are analyzed as well as the steps of troubleshooting and treatment for them are summarized and introduced combining with the experiences of on-site maintenance and fault handling for AGC hydraulic control system for wide and thick plate mill, which can be as references for design, maintenance, fault diagnosis, system optimization and improvement of AGC hydraulic control system for rolling mill.

On the premise of constant production and operation of gas desulfurization system, such goals as reducing its operating load, stabilizing the operation of desulfurization facilities and reducing the emission concentration of pollutants at outlet are achieved through taking such measures as adjusting the proportioning of sintering raw material structure, controlling the temperature and flow rate of flue gas as well as improving the efficiency of main electrostatic precipitator.

In this paper, it is mainly introduced the principle and implementation method of double cross-limit control as well as the parallel cascade combustion control system based on double cross-limiting is designed on the basis of briefly elaborating the technological process of hot blast furnace. The practical applications show that the automatic control for combustion and blowing-in of hot blast stove can be realized as well as the combustion efficiency and control accuracy of hot blast stove are greatly improved with the system so that hot blast stove can operate safely and efficiently.

It is found that the main cause for surface defect of billet is low straightening temperature aiming at the problem that the surface crack rate of Q355B casting blank produced with the 280 mm × 380 mm billet and 5^# casting machine of Baotou Steel is higher through studying the correlation between straightening temperature of billet and surface cracks. The high temperature thermoplasticity of steel could be changed by adding trace Ce element so that the probability of surface cracks for billet is greatly reduced within the straightening temperature range of 850~950 ℃.

The effects of different TiO₂ contents on the basic characteristics of sintering and quality index of sinter are studied with small sintering method and sintering cup. The study results showed that the liquid phase fluidity index and generative capacity of calcium ferrite decreased, the strength of binder phase tended to decrease and strength of crystal stock tended to increase with the increases of TiO₂ content in iron charge and assimilative temperature; the yield and drum strength of sinter decreased as well as solid fuel consumption tended to increase; the magnetite content in mineral composition of sinter tended to increase, crystal obviously increased, production of calcium ferrite decreased, perovskite content tended to increase and the change of hematite was not obvious; the low-temperature reduction degradation index of sinter tended to get worse and melting range became narrower.

In this paper, it is introduced the development process of video monitoring system and video protocol, analyzed the current situation and existing problems for video monitoring system as well as the purpose and significance of video monitoring system integration in Baotou Steel. The feasible integration scheme for several video monitoring systems with different private codes and transmission control protocols is proposed, which is with certain practical values.

In this paper, it is considered to be the main cause for decline of dissolved oxygen that the load of organic matter in aerobic tank increases rapidly by analyzing the typical example for decline of dissolved oxygen in aerobic tank of biochemical system for coking waste water. Verified by experiment, the concentration of dissolved oxygen in aerobic tank could return to normal within 1~2 days by taking such measures as increasing the aeration rate of aerobic tank, adding the water with low COD concentration into aerobic tank and strictly controlling the amount of organic matter entering aerobic tank.

It is a key link to detect the oxygen and nitrogen content in rail blanks in the production of rails. In this paper, it is mainly elaborated the method for preparing oxygen and nitrogen sample with drilling of hollow drill instead of traditional gas cutting forging. The experiment results showed that the method could meet the production requirements. Moreover, the process flow was simplified, sample preparation cycle was shortened, cost of sample preparation was reduced and timeliness of data was ensured compared with the method for preparing oxygen and nitrogen sample with gas cutting forging.

Woerte Mining Co., Ltd. processes various ores. The content of rare earth in the tailings after beneficiating iron is higher, the rare earth in tailings of Woerte is effectively recycled with the flotation method and thought of individual processing aiming at the problems of complex ore properties and many influencing factors for mixed ore. The results showed that under the better experimental conditions, the rare earth ore concentrate with concentrate grade of 52.00% and recovery rate of 56.05% was finally obtained so that more significant economic benefits were obtained.