In this paper, the causes and influencing factors for tailing of flue gas and smoke plume in wet flue gas desulfurization process with gypsum process are analyzed. The effective measures to control them are put forward based on the controllable main factors. With the overall consideration of source, process and end, the output of such pollutants as particle and SO₂ can be controlled from the source with the matching process of low-sulfur crude fuel; the operating efficiency of gas desulfurization system is improved and the concentration of SO₂ and particulate at vent tower is reduced with such measures as adopting premium desulfurizer, improving the efficiencies of dust collection and demisting as well as optimizing gas liquid ratio; the desulphurized flue gas is with such measures as dehumidifying and heating so that the wet flue gas at chimney breast cannot reach the saturation condition after mix with the air and the condensate water cannot be formed so as to achieve the purpose of eliminating tailing of smoke plume.

The iron ore deposit is divided into east and west ore blocks. The east ore block is composed of five ore bodies controlled by the 42 and 46 lines and the west ore block is composed of two ore bodies controlled by the 30 line. They are over 800 m apart and connected with convergent and narrow skarn zone in the middle. There are seven ore bodies in total and their common features are that they are stratiform-like or stratiform, north-dipping, the upper dip angle is gentler and the lower one is slightly steeper, the upper part is thinner and the lower part is thicker gradually as well as there is a tendency to expand and extend to the deep. The graphite deposits are distributed between the 38~50 lines, forming a total of 8 ore bodies. According to the mineral combination and metamorphic grade of ore-controlling rocks, the deposit is considered to be a regional sedimentary metamorphic deposit.

In this paper, it is introduced the study on replacing part of premium Shanxi coking coal with new coal source in Coke Chemical Engineering Branch Co., which is demonstrated through iron case, small coke oven and industrial experiment. Finally, it is popularized and applied in practical productions so that the cost of coal blending is reduced.

In this paper, the production practices for improving stability ratio of furnace temperature for 4^# blast furnace of Baotou Steel are summarized. It is greatly improved by strengthening the management of crude fuels, adjusting the charging system, exploring appropriate thermal system, strengthening the operations for stability of slag crust of copper cooling wall as well as implementing the standard operations and daily examination system of blast furnace, which lay a foundation for stable and trouble-free operations of blast furnace.

In this paper, the factors affecting the w [S] in pig iron are analyzed and discussed by referring to the corresponding relationship between main production parameters and w [S] in pig iron. The results showed that damping down has effects on w [S] in hot metal, but not obvious; the effects of sulphur load on quality of hot metal are obvious and their corresponding relationship is good, therefore, it is significant to reduce the sulphur load in furnace for improving the quality of pig iron; stable furnace temperature is the premise for stabilizing the quality of hot metal; in order to improve the quality of hot metal, the basicity of slag must be increased and stable; when the utilization ratio of gas was stable, it is beneficial to desulfurization of hot metal.

The stability for liquid level of molten steel for crystallizer is an important factor affecting the quality of continuously cast bloom. In this paper, the control principle and limitations for liquid level of molten steel for crystallizer of Baotou Steel are studied. A new three-dimensional measurement method and stability control technology for it are researched and developed so that the operation process is optimized, its control level is improved, the inclusions in continuously cast bloom are reduced as well as the quality and performance of bloom are improved.

In the paper, it is investigated the corner crack defect of continuous casting sheet billet, analyzed its causes from the process, operations and devices. The uneven thermal stress and mechanical stress on solidified slab shell are improved through such a series of improvement measures as improving the quality of molten steel, adjusting the cooling water and secondary cooling water consumption of crystallizer as well as improving the on-line equipment performance and chamfered crystallizer so that its occurrence rate is reduced and the quality of continuous casting sheet billet is improved.

The Q690D steel is the microalloying low-alloy high-strength steel with the yield strength of 690 MPa grade developed by Baotou Steel. It is with excellent low-temperature toughness, mainly used for engineering and mining machinery as well as the delivery of steel plate is in quenched and tempered condition. In order to grasp its basic weldability, the welding and postweld heat treatment technologies are formulated reasonably to make the performances of its welded joint meet the use requirements of industrial and mineral products. In the paper, the sensitivity of welding cold cracks, welding and postweld heat treatment technologies as well as comprehensive mechanical properites of its welded joint are with experimental study and assessment.

Since the original emission system for blast furnace gas and coke oven gas of Baotou Steel was affected by such factors as the quality of ignition gas, climate and equipment, gas was directly emitted due to extinction of accompanying flame so as to cause the air pollutions even poisoning accidents. The emitted gas is burnt and emitted fully with the sufficiently large ignition and accompanying flame generated by the stimulation of step electric arc and reaction of catalyst to self-emitted gas through improving the emission tower of our company with the direct-fired ignition device. As a result, the stability of equipment operation is good, emission after ignition is safe and reliable as well as a lot of fuel gas cost and maintenance charge are saved.

In this paper, the microstructure and properties of hot rolled 600 MPa grade dual phase steel plate for automobile structure are compared with those of hot rolled pickling plate. The results show that both of the yield strength and tensile strength are improved after pickling, there is no great change for elongation as well as the performances of hot rolled pickling plate could meet the requirements of standard; due to the work hardening of plate caused by withdrawal and straightening process before pickling, the impact energy values of pickling plate are lower than those of hot rolled plate with a series of thermal shock tests; after the pickling process, the microstructure is a large number of polygonal ferrite and a small amount of martensite, the grain size is changed from grade 10.5 to grade 12.0 and grain becomes finer because of cold deformation.

The high-strength automobile carriage steel BT600XT is successfully developed with the 2 250 mm hot continuous rolling production line of Baotou Steel by adopting the alloy design scheme of low carbon, sulfur and phosphorus as well as adding microalloy elements, niobium and titanium. It is with excellent overall performance and cold roll forming performance as well as the strength and toughness match well, which could fully meet the user requirements.

In the paper, the microstructures and properties of hot rolled dual phase steel DP590 with two component systems are compared and analyzed. The results show that the differences of microstructures for experimental steels are not obvious; the strength of experimental steel with C-Si-Mn-Nb component system is higher than that of experimental steel with C-Si-Mn component system, the surpluses of its yield strength and tensile strength are moderate, 81 MPa and 103 MPa respectively as well as the impact toughness and comprehensive mechanical properties are better, which are favorable for stable batch production.

The YQ450NQR1 Z-type steel is cracking during the rolling process so that it is determined to be rejected. Its causes are found out and reasonable control measures are put forward by metallographic examination, detection analysis of inclusions and scanning electron microscope.

Since the demand of high-grade fasteners in the fastener industry is increased year by year, the ML35CrMo alloying cold heading steel wire rod is developed. In this paper, it is introduced the non-metallic inclusions, mechanical properties, cold heading and rockwell hardness of quenched and tempered finished wire rod could all meet the standard requirements through controlling such processes as converter smelting, refining, continuous casting and rolling for ML35CrMo cold heading steel as well as selecting heat treatment system for wire rod.

In the paper, the high temperature plasticity of 15MnNbV was tested with MMS-200 thermal simulated test machine. The results showed that the reduction of area of 15MnNbV at 900 ℃ was only 26%, temperature of round billet entering straightening segment was about 900 ℃ during continuous casting, with the stress of straightening roll, there was easily to be microcracks on the surface of round billet, especially the Ф430 mm round billet causing wall scale on outside surface of steel tube. The composition of 15MnNbV was adjusted through analyzing the influencing factors for high temperature plasticity of steel and characteristics of precipitation for niobium and vanadium in steel. After that, the reduction of area of 15MnNbV at 900 ℃ reached 88%, surface quality of round billet was improved and wall scale on outside surface of steel tube was eliminated.

In the paper, it is introduced the two-sided threading cutting head is designed with two sides and multi style to realize the two-sided threading and utilization through reforming the threading cutting head aiming at the problems in threading productions of Steel Tube Co. of Baotou Steel, with which 4.23 million yuan can be saved for one year so that good economic benefits are created for the enterprise.

In the paper, the faults of impact hammer mill are analyzed, the main causes for rotor vibration are rectified and reformed as well as the optimization and improvement measures for impact hammer are proposed, with which the effects are good.

The coiler for trimmings is an important equipment for the rewinding unit of silicon steel production line of CSP Plant. At the beginning of constructing the production line, there were such equipment problems of coiler for trimmings in the process of rewinding silicon steel as guard dise of mandrel blocking belt, oversize bounce of press roll and abrasion of copper slider for winding device. They are solved through redesigning and improving the relevant functions of coiler for trimmings so that the equipment failure rate is effectively decreased, service cycle of spare parts and the production capacity of rewinding production line are improved.

In the paper, it is analyzed the process for scrap caused by off tracking of hot continuous rolling strip steel when entering rolling mill and passing through belt as well as the camber of head impacting the guide plate at inlet side. The physical process and influencing factors of scrap caused by impacting guide plate are determined through detailed analysis on the data of heating, rough rolling and finish rolling processes. The main preventive measures are determined from the aspects of heating temperature, plate shape of rough rolling, operation and equipment accuracy so that its probability is reduced.

In this paper, it is introduced the working principle and advantages of oil-gas lubrication as well as analyzed the exsiting problems in the applications of oil-gas lubrication system of withdrawal straightener of 6^# continuous casting machine. Moreover, the improvement measures are put forward and applied successfully.

In the paper, the system of shipment and write off for ERP of Baotou Steel based on J2EE is discussed. The company's business model of shipment with railway and highway is as the research object aimed at providing a friendly management platform of shipment and write off for users. The system is developed with MVC development mode, two functional modules, the management modules of railway shipment and write off as well as the highway shipment and write off are designed to meet the current demand for shipping management system through in-depth study of shipping management mode.

In this paper, it is introduced the composition of supply unit for 25 kg and 100 kg medium frequency induction furnace in a laboratory and the specific functions of each device, analyzed the changing rules of medium-frequency power supplies with parallel resonance and series resonance in rectification and contravariance, given the calculation formulas of main parameters as well as compared and analyzed combining with the actual use. The results showed that the medium-frequency power supply with series resonance was easy to be started, which was more suitable in workplace with frequent start; while the medium-frequency power supply with parallel resonance was more difficult to be started, which was not suitable to be used in workplace with frequent start, but it was with strong adaptive capacity to the load so that it was more used in workplace where the smelting steel grade changed at any time.

In this ppaer, the main problems of sewage treatment plant in industrial park concerned in environmental impact assessment process including such as the analysis on process plan of sewage treatment and treatment measures of foul gas are discussed aiming at the complexity of sewage in industrial park by taking a Sewage Treatment Plant in an industrial park as an example, which can be as reference for fraternities.

The chromium-containing wastewater in galvanization is a kind of wastewater with larger discharge amount in the electroplating industry. It contains the heavy metal chromium, which can cause serious pollution to the environment if discharged arbitrarily. In this paper, the treatment process of chemical precipitation method + biological active carbon + ultrafiltration + reverse osmosis + evaporation crystallization is adopted for chromium-containing wastewater. It is mature as well as the treatment effect is stable and reliable, which could meet the requirements for zero discharge of chromium-containing wastewater and be as the reference for fraternities.

With the enhancement of national environmental requirements, it is necessary to change the mode of open－air coal piling and it is urgent to seal the coal yard. After the coal yard is sealed, the working environment of staff is sealed and with more coal dust, so the safety issue needs to be paid urgent attentin. In the paper, the gas, dust and temperature monitorings in coal yard are realized as well as the early warning is given combining with the design and applications of safety monitoring system in a sealed strip-type coal yard so as to ensure the safety of personnel and coal yard.

In this paper, it is introduced the design and construction process for high-formwork support system, focused on checking and analyzing the support system of beam. The measures and suggestions for its construction management including the selection of supporting formwork materials, calculation of load for supporting formwork and setting up of formwork support are put forward, which could be as reference for the constructions of other similar projects.

The uncertainty of manganese content in SWRH82B steel determined with spark source emission spectrometry is evaluated according to the "Evaluation Specification for Uncertainty of Measurement Results for Low Alloy Steel with Spark Source Emission Spectrometry", the main sources as well as such components affecting uncertainty as measurement repeatability, standard values of standard samples and curve fitting are analyzed. Finally, the combined standard uncertainty and expanded uncertainty are calculated as well as the main factors affecting uncertainty are found out. The test results showed that the uncertainty caused by standard values of standard samples is the main source of uncertainty with this method. When the manganese content in SWRH82B steel is 0.69%, its expanded uncertainty is 0. 02% (k = 2). Based on the analysis of uncertainty, an analytical method for determining the uncertainty of manganese content in SWRH82B steel is established, which provides the scientific basis for reasonably evaluating the laboratory test results.