首钢矿业烧结厂用水煤浆点火试验获得成功

首钢矿业烧结厂建厂以来 ,在烧结生产中 ,一直使用重油点火。由于重油短缺 ,市场价格猛涨 ,增加了烧结矿成本。为了降低成本 ,增加效益 ,该厂采取厂校挂钩的办法 ,进行了多方面的探索 ,他们开发的“重油乳化及再辐射聚焦点火技术” ,尽管使烧结矿生产的重油消耗降低了 5 4 % ,但重油消耗在烧结矿制造成本中的比重依然很大。水煤浆是一种新型的煤基流体燃料。象重油一样 ,水煤浆可以泵送、雾化和贮存 ,具有着火稳定、燃烧效率高等优点。在首钢矿业公司有关单位协同对水煤浆进行了深入考察和性能、价格分析的基础上 ,请北京科技大学作为技术指…     

水煤浆与煤粉在轧钢连续加热炉上的应用对比试验

本文介绍了在国内外首次进行的轧钢连续加热炉燃用水煤浆的初步工业试验结果,并与原燃用煤粉进行了多种对比。结果表明,水煤浆在启动点火、升温加热方面和煤粉相当,能够满足钢坯轧制前加热的各种工艺要求。而在燃烧调节、稳定加热炉工况、减少氧化烧损和环境污染以及经济效益等方面却明显优于煤粉,所以对于轧钢连续加热炉而言,水煤浆是一种现实可行的清洁燃料。     

工业炉窑燃用水煤浆成套技术的研究开发

介绍了北京科技大学研究开发的工业炉窑燃用水煤浆成套技术。其中，厂区管道输送技术给出了根据水煤浆流变特性而确定的管道设计参数，水煤浆的储存技术给出了不同情况下解决防冻问题和防止沉淀问题的方法，炉前处理技术给出了水煤浆在线过滤和炉前降低粘度以利于雾化燃烧的措施，燃烧器、燃烧组织及改炉技术则根据不同炉窑的工艺要求介绍了如何实现水煤浆的高效、稳定燃烧和怎样解决以水煤浆代油所带来的某些问题。     

云南褐煤水煤浆成浆性分析

介绍了一种云南褐煤水煤浆的成浆性能。试验得出云南褐煤因内在水分高且含氧量较高,故水煤浆浓度较低;3种添加剂对改变云南褐煤成浆性能作用不同,上海焦化厂水煤浆添加剂对其成浆性能较好,可作云南褐煤制水煤浆添加剂;选择上海焦化厂水煤浆添加剂,在加入量为1%的条件下,制得水煤浆性能指标较好,煤浆最高浓度接近50%。     

优化能源结构,充分利用副产资源

介绍了太钢充分利用副产煤气资源节能的５个措施：即焦炉煤气置换、煤气代替重油、副产焦油代替重油、煤气代替煤炭、副产煤气代替发生煤护煤气等。     

烧结用水煤浆点火器的开发

针对当前烧结机燃油点火器能耗高、寿命短、点火不均匀等现象，研制开发了采用曲面聚焦辐射并在炉壁上喷涂高黑度辐射涂料的燃用水煤浆点火器。该点火器能在料面宽度方向形成均匀的点火带，达到理想的点火效果，其点火快速、均匀、节约能源，具有很好的经济和环保效益。     

转炉煤气烧结点火工艺改造及生产实践

石横特钢通过改造点火器及转炉煤气管网设备,确定最佳空煤比、点火温度、点火时间、点火负压等控制参数,实现了转炉煤气代替高炉煤气用于烧结点火。采取稳定转炉煤气热值和压力、低负压点火、厚料层烧结等工艺技术措施,降低了煤气消耗。改造后烧结机利用系数提高0.05 t/(m~2·h),成矿率提高2.6%,固体燃料消耗降低1.5 kg/t,电耗降低1.0 k Wh/t,转炉煤气单耗约20 m~3/t。     

降低265m~2烧结系统点火煤气耗的实践

介绍在265 m~2烧结生产线实施的微负压低温点火技术、优化点火空煤比、优化AB排烧嘴点火强度、稳定并优化生产操作等措施,其效果是使点火煤气耗由4.5～4.8 m~3/t降到3.5～3.8 m~3/t。     

顶燃式水煤浆烧结机点火器的开发与应用

针对当前烧结机燃油点火器燃料费用高、寿命短、点火不均匀等现状,研制开发了点火器喷嘴顶部布置的燃用水煤浆的烧结机点火器。工业应用表明该新型节能点火器具有理想的点火效果,能够有效地提高烧结矿质量与产量,并且还能大幅度延长点火器的寿命,经济效益和环保效益显著。     

水煤浆在烧结机点火器上的应用

介绍了国内首次在烧结机点火器上进行的水煤浆燃烧应用试验。结果表明，研制的水煤浆点火器对各种水煤浆和不同的雾化介质均有很好的适应性，均可达到理想的燃烧效率和点火效果，该技术的推广应用具有很好的经济效益和环保效益。     

激光熔覆涂层的浆体磨损特性及其应用研究

采用激光熔覆技术在４５钢试样表面获得镍基合金和ＷＣ颗粒增强的镍基合金复合材料涂层。研究了激光涂层工艺、熔覆层的组织结构和水平－煤－石英砂浆体的磨损特性,并将研究成果成功地应用于矿用渣浆泵平衡盘等零件。     

固体热载体煤气化试验装置提升段燃烧试验

固体热载体煤气化的热量靠提升燃烧产生。介绍了褐煤焦载热煤气化提升燃烧的点火、燃烧和调节。根据点火曲线，可将其分为加热、着火和燃烧三个阶段。调节提升风量能很好地控制燃烧工况，加大气化煤量可增加提升燃烧的易燃成分，从而提高燃烧温度。     

煤代油技术之比较

对两种经济实用的煤代油技术——水煤浆和发生炉煤气进行了分析对比，讨论了这两种燃料的燃烧特性以及原燃油热工设备对它们的适应性。     

Combustion Property and Kinetic Modeling of Pulverized Coal Based on Non-isothermal Thermogravimetric Analysis

Non-isothermal combustion kinetics of two kinds of low volatile pulverized coals （HL coal and RU coal） were investigated by thermogravimetrie analysis. The results show that the combustibility of HL coal was better than that of RU coal, and with increasing heating rate, ignition and burnout characteristics of pulverized coal were improved. The volume model （VM）, the random pore model （RPM）, and the new model （NEWM） in which the whole combustion process is considered to be the overlapping process of volatile combustion and coal char combustion, were used to fit with the experimental data. The comparison of these three fitted results indicated that the combustion process of coal could be simulated by the NEWM with highest precision. When calculated by the NEWM, the activation energies of volatile combustion and coal char combustion are 130.5 and 95.7 kJ · mol^-1 for HL coal, respectively, while they are 114.5 and 147.6 kJ ·mol^-1 for RU coal, respectively.     

燃烧效果最佳的混煤喷吹配比计算方法

在归纳和比较常用高炉喷吹配煤方法的基础上,以计算法配煤的思想为指导,提出了以实现最佳燃烧效果为目标的混煤模型.通过曲线拟合得到混煤着火点随高挥发分煤种配比增大而减小的关系曲线,混煤着火点下降速率减小到某一较小值时的混煤比例即为该煤种组合燃烧效果最佳的比例.应用该方法对四组不同煤种组合混煤进行配比优化,经静态燃烧性实验证明,该计算法所得结果准确可靠,有一定实用性.      

Dewatering of Tunneling Slurry Waste Using Electrokinetic Geosynthetics

Laboratory experiments are described that investigate the potential for using electrokinetic geosynthetics (EKGs) [materials that permit the combined exploitation of geosynthetics with electrokinetics (EKs)] to dewater slurry waste from a tunneling operation. The results demonstrate that the EK is reproducible for different slurries and that the process can significantly dewater tunneling slurry wastes. Higher electrode element surface area, increased potential gradient, and longer processing time increase water removal from a slurry waste. Higher potential gradients and current densities were found to consume more energy, with thicker samples (lower voltage gradients) and close element spacing using less power to achieve a particular dewatering efficiency than other configurations tested. The resultant pH of the treated slurry and the effluent water were found not to be sufficiently altered by the EK process to prevent their safe disposal or reuse. The potential of three different forms of EKG to treat tunneling slurry are discussed and a conceptual scheme for an EK enhanced belt press is proposed. While further investigation would be required to optimize their operating parameters, preliminary designs, and cost estimates can be based on the results presented herein.     

高炉采用氧煤燃烧器后回旋区煤粉燃烧过程的数值模拟

针对高炉风口前回旋区内氧煤燃烧器喷入煤粉燃烧的过程，应用数值模拟方法对氧煤燃烧器在不同喷煤粉量和氧浓度条件下的燃烧过程进行了计算机数值模拟。结果表明，高炉风口产生的回旋区流场及温度场有利于煤粉的燃烧，而氧浓度大则有利于煤粉较早着火及较高的燃烬率。     

Non-dendritic Structural Changes in Al–7Si Alloy Cast Through Rapid Slurry Formation (RSF) Process

Rapid slurry formation (RSF) is a semi-solid metal forming technique, which is based on a so-called solid enthalpy exchange material. The beauty of the process is that the slurry is controlled by relative added amounts of the alloy system used. It is not necessary to accurately control the heat flux to surrounding media such as, crucible or mould. In the present investigation 15?% solid fraction in Al?C7Si alloy slurry has been produced by RSF method. The slurry so prepared was cast in gravity die cast mould with water cooling arrangement. Thus ingot of size 30?cm?×?5?cm?×?2.5?cm could be produced. The microstructure showed rosette and globular type ??-Al morphology. Tensile properties evaluated were higher than as cast Al?C7Si alloy. During slurry formation coarsening of particles was experimentally investigated and also theoretically described by Lifshitz-Slyozov-Wagner (LSW) theory and convective mass flow equations.