Affecting Factors and Improving Measures for Converter Gas Recovery

To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No. 2 steel- making plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air im bibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc. , and good results were achieved.

Numerical Simulation of Three-dimensional Heat and Mass Transfer in Spray Cooling of Converter Gas in a Venturi Scrubber

In order to predict the pressure drop, collection efficiency, velocity, temperature and mole fraction of vapor in an industrial venturi scrubber with water spraying for converter gas cooling, a three-dimensional model of heat and mass transfer with phase change is established. The gas flow and liquid droplets are treated as a continuous phase with a Eulerian approach and as a discrete phase with a Lagrangian approach, respectively. The coupled problem of heat, force, and mass transfers between gas flow and liquid droplets is solved by a commercial computational fluid dynamics（CFD） package, FLUENT. The numerical results show that the water injections have an important influence on the distributions of pressure, velocity, temperature, and mole fraction of vapor, especially for the spraying region in the throat. In the spraying region, the pressure drop is higher and the velocity is lower than in other regions due to the gas-droplet drag, while the temperature is lower because the droplet absorbs large amounts of heat from the high temperature gas and the mole fraction of vapor is higher due to the phase change of the liquid droplet. A number of cases with different Water-to-gas volume flow ratios and baffle openings were simulated. The dependence of pressure drop, velocity, temperature, mole fraction of vapor, and collection efficiency on both the water-to-gas volume flow ratio and baffle opening are analyzed. The good agreements between simulation results and experiment data of pressure drop, temperature, and collection efficiency validate the model. The model should facilitate optimization of the venturi scrubber design in order to give better performance with lower pressure drops and higher collection efficiency.

Study on Influence of Gasoline Sulfur Content on Performance of Vehicle Exhaust Catalytic Converter

This paper has investigated the influence of gasoline sulfur content on durability of catalytic converter for vehicle exhaust gas. Two gasoline samples with different sulfur contents (equating to 150 μg/g and 50 μg/g of sulfur, respectively) were used to examine the durability and performance of catalytic converter on the bench test. The test results have revealed that in comparison to the influence of sulfur on ageing of catalytic converter the thermal ageing had a more remarkable impact on the performance of catalytic converter, and the performance of catalytic converter could be restored by high-temperature desulfurization process after ageing by the high-sulfur gasoline sample (containing 150 μg/g of sulfur) .

Converted-wave diodic moveout and application in the land gas cloud area

PS converted-waves （C-waves） have been commonly used to image through gas clouds but the C-wave imaging may also be degraded by the diodic effect introduced by the gas cloud. It may be compensated for using a velocity perturbation method which decouples the diodic moveout into two parts： the base velocity and the velocity perturbation. Gas clouds are widely distributed in the Sanhu area in the Qaidam basin of northwest China which is rich in natural gas. A land 2D3C seismic dataset is analyzed from the Sanhu area and significant diodic effects are observed in the data which harm the C-wave imaging. The diodic correction is applied to this data and the resultant C-wave imaging and the details of the reservoir structure are significantly improved. The diodic moveout plays an important role in working out the residu~ shear wave statics and the association of diodie correction and shear wave residual statics computation is a key step of C-wave high fidelity imaging in the gas cloud area. Finally, the new process workflow with diodic moveout is given.

The gas reservoir response in PP- and PS-wave frequency sections

Spectral decomposition using the method of Matching Pursuit Decomposition （MPD） for PP- and PS-wave data has higher resolution and higher consistency over the entire time-frequency plane. The MPD algorithm avoids the problems of inaccurate analytic time point and the time window size choice that may occur during a Fourier transform. The PP-wave attenuation is greater than the PS-wave attenuation while propagating through gas reservoirs. There are some stronger amplitude low-frequency shadows on the PP-wave single frequency sections beneath gas reservoirs which are not seen on corresponding PS- wave single frequency sections. Therefore, hydrocarbons are predicted from comparing the behavior on both frequency sections. The time-frequency analysis for multi-component data is decomposed by MPD for data from northeast China containing rich gas reservoirs. The gas response character is analyzed on different wave mode single frequency sections. We describe the MPD algorithm, compare it to other spectral decomposition methods, and show some examples of detecting low-frequency shadows beneath gas reservoirs.

Strategies of ＂Power-off Reset＂ Failure for Siemens MM440 in the Application of Gas Press

Gas pressurized fan speed control and remote monitoring was achieved based on three sets of gas pressure MM440 frequency converter control system, through the Profibus-DP network transmission of exchange data and signal instructions. In operation, one converter which adopted ＂ power-off reset＂ has broken down, so as to cause two other gas pressurized frequency converter tripping. This paper proposed method to achieve capture and process failures, and application to converter control system. The result shows that the present method solves the fault, improves the system operation stability and meets the requirement of production.

Thermodynamic analysis of improvement of converter gas by injecting pulverized coal into vaporization cooling flue

In order to improve the calorific value and the recovery yield of converter gas during the steelmaking process, a novel and thermodynamically admissible process was proposed. This method involved injecting pulverized coal into the vaporization cooling flue of a converter, and the approach was developed based on an industrial 30 t converter. The effects of temperature, O2 content, and the volumetric ratio of CO to CO2 on the conversion of the mixed components of gas were analyzed using thermodynamic calculations. Furthermore, the effect of the injection rate on the quality and quantity of gas was investigated. The results show that the O2 and CO2 components of flue gas decrease as the injection rate increases, whereas the CO and H2 components synchronously increase. With the injection rate of 30 kg min-1, the 02 and CO2 components of the gas decreased by 64.12 and 41.19%, respectively, while the CO and H2 increased by 20.09 and 236.84%, respectively, and the recovery time of gas increased by 11.61%, compared to non-injection.

宝钢高炉热风炉新技术的开发与应用

宝钢通过热风炉技术研究和生产操作改进,开发出一系列热风炉高风温技术,如热风炉余热回收、转炉煤气(LDG)烧炉、富氧烧炉、计算机模型烧炉等,使宝钢高炉风温可以长期稳定在1 250℃左右,最高可以达到1280℃, 热风炉高风温技术达到国际先进水平。

起止回收CO体积分数影响转炉烟气能量回收的规律分析

转炉炼钢工序转炉烟气显热、潜热回收是“负能炼钢”的核心。以某钢厂300 t顶底复吹转炉为例,建立了转炉烟气中CO、O_(2)体积分数随吹炼时间变化的特征模型,分析了起止回收CO体积分数对转炉煤气回收量及热值、蒸汽极限回收量的影响规律。结果表明,当起止回收CO体积分数增加±1%,转炉煤气回收量减少±0.50 m^(3)/t,热值增加±22.3 kJ/m^(3),蒸汽极限回收量增加±1.77 kg/t。最后从转炉煤气回收、转炉烟气高温显热回收、转炉吹炼初末期低热值煤气回收利用三个角度分析了提升转炉烟气余热余能回收利用率的途径。

Offshore Multi-Wave Seismic Exploration in Bohai

In Oilfield A, of south Bohai, the large area (20km^2) of gas in the shallow layer of the main structure makes a "gas cloud" effect in the seismic section. It makes the seismic migration imaging of the deeper aim layer inconsistent with the actual features of a geologic structure. But, the converted waves,PS waves, containing effective information of incident compressed (P) waves, can create converted S waves. The S wave is affected little by the shallow layer screen, allowing better imaging of the deeper layer. So, 4C seismic acquisition was carried out on the structure. Through geologic reconnaissance on the site, shallow layer drilling analysis and multicomponent seismic experiments, the offshore acquisition flows are designed. Choosing appropriate processing flows for converted waves and paying attention to the key tache of processing, a high quality 2D converted wave section was obtained. By identifying the character of the seismic wave correctly, making use of the full wave logging, producing synthetic converted wave seismogram, and identifying horizon, we can carry out structure interpretation and reserve evaluation of the oilfield.

双转炉煤气柜并网回收煤气

宁波钢铁转炉煤气(LDG)系统采用双转炉煤气柜并网回收煤气,2座气柜可互为备用,解决每座气柜大修时无法回收转炉煤气问题,同时2座气柜实行直列运行,减少生产节奏变化大造成柜满拒收的现象,提高了转炉煤气回收率,对宁钢的"节能减排,降本增效"起到积极的作用。

转炉煤气回收影响因素对比分析

讨论铁水质量、转炉冶炼、运行方式、检测等对转炉煤气回收的影响,结合三座钢厂实际情况对比分析了以上因素对转炉煤气回收的具体影响情况,对提高转炉煤气回收工作具有一定参考。

湛钢350 t转炉煤气回收潜力分析

文章针对湛江钢铁350 t转炉的煤气回收量较低的问题,通过分析历史数据,研究了转炉煤气回收量降低的主要工艺因素以及影响程度,提出了增加转炉煤气回收量的有效措施。在实践中取得了显著的成果,具有一定的借鉴和推广意义。

Practice of improving the hot blast temperature for the 2500 m^3 BF

A high blast temperature is an effective measure that improves pulverized coal injection （PCI）and energy consumption,decreases the cost of blast furnaces （BF）. Apart from using technology such as the increased vault temperature of the hot-blast stove, the increased temperature of the waste gas, the preheating of combustion air and gas, and fully closed mixed air valves, other measures, such as using an oxygen-enriched blast stove, burning high heating value converter gas, increasing the number of stove changes to reduce the time needed for stove blasts, were taken to increase the blast temperature of the 2 500 m3 BF in recent years. The blast temperature of the 2 500 m3 BF was continuously increased in these years. The monthly average temperature of the 2 500 m3 BF reached 1 158℃, with the highest blast temperature reaching 1 195 ℃ in 2006. This technique of increased blast temperatures has reached an advanced level in China.

Status and Prospect of CTL and SNG Industry

Since the beginning of this century, revolutionary progress has been made in the understanding of resources and in the mining technologies of the oil and gas industry. Advances in petroleum engineering technology represented by horizontal wells and large-scale fracturing have promoted the scale development of low-grade and unconventional oil and gas resources. After the rapid growth of natural gas production in China for more than 10 consecutive years, the replacement of conventional natural gas resources has been weak and unconventional natural gas has become the major force for increasing production. Coal based SNG(synthetic natural gas) has also become a major competitor in the domestic market. The development of CTL(coal-toliquids) and SNG industries has brought coal resources into the oil and gas product market, expanding the concept of traditional oil and gas resources. The continuous improvement of petroleum engineering technology has promoted the development of deep underground coal gasification technology, which has given economic value to the huge amount of deep coal resources that are unable to be exploited by underground mining, and provides a tremendous resource guarantee for the sustainable development of the traditional oil and gas industry. A preliminary calculation shows that deep underground coal gasification has a competitive advantage in cost compared with high-cost, low-grade, unconventional gas and coal-based natural gas. Deep underground coal gasification is a typical cross-disciplinary and cross-sectoral sophisticated technology. Domestic oil and gas enterprises have dominant advantages in the engineering technology of this field. Further technical integration innovation and multi-industry joint research are needed to eventually realize the commercial application of this deep underground coal gasification technology.

Study of Multilayer Flow Insulation Utilizing Open-Cellular Porous Plates

To improve the performance of the single layer flow insulation system utilizing open-cellular porous plate, the multilayer porous gas enthalpy-radiation converter is proposed and investigated experimentally and theoretically. Two open-cellular porous materials with different porosity pore per inch and surface reflectivity have been examined. Each porous plate has the same thickness of a half of the single layer one. Both porous materials are not combined continuously but divided by free space. For the prediction model, two energy equations of the fluid and solid phases are employed, in which the convective heat transfer between both phases is described based on the empirical volumetric heat transfer coefficient. In addition, the radiative transfer equations are resolved by Pj approximation. When an equivalent blackbody radiation temperature of the radiation coming from the upstream region exceeds inlet gas temperature, use of a high reflective porous plate on the upstream side and a low reflective porous plate on the downstream side is quite effective to increase gas temperature drop across the converter. the multilayer porous converter should be made of pure scattering and porous layer, respectively. In order to obtain maximum gas temperature drop in that case, pure absorbing porous plate as the upstream and downstream

Development of CO_(2) capture and utilization technology in steelmaking plant

The performance of a recycling process for CO_(2) capture and utilization of exhaust gas in the steelmaking plant was reported.A facility capable of capturing CO_(2) at 3200 m^(3)/h was established in the steelmaking plant,resulting in the CO_(2) production of 50,000 t/a.The CO_(2) concentration of the exhaust gas from the lime kiln increased from 25.0 to 99.8 vol.%using the comprehensive method of the pressure swing adsorption and cryogenic separation.The captured and purified CO_(2) was successfully applied in the converter process by the top blowing and bottom blowing.The utilization of CO_(2) was 3.5 m^(3)/t through these two modes.After optimizing parameters of CO_(2)-O_(2) mixed top blowing,the value of[C]×[O]and the content of TFe in slag were reduced by 1.33×10-4 and 1.27%,respectively,and the dephosphorization rate of the molten steel increased by 2.31%.For the CO_(2) bottom blowing,the[N]content in the molten steel was significantly reduced by 5.7×10^(-6).