助熔剂CaO对高铬砖抗渗透性能的影响

在水煤浆气化炉煤渣中加入助熔剂CaO,采用半球点法和吊丝法测量煤渣灰熔点和高温粘度；在高铬坩埚中加入等量的CaO的含量分别为26.5％,28.5％,30.5％,32.5％,33.5％,35.5％的煤渣,1600℃×8h空气气氛下静态坩埚法抗渣实验,研究煤渣对坩埚的侵蚀.结果表明,渣中CaO含量越多,煤渣灰熔点和高温粘度越低；当渣中CaO含量低于32.5％时,坩埚表面均有挂渣层；CaO含量越多,渗透越深,渗透最深为12mm;当渣中CaO含量超过32.5％时,坩埚表面无挂渣层,渗透深度达到15mm,SEM分析,高铬砖结构被破坏,铝铬固溶体孤立地存在,周围布满大气孔,大大降低了高铬砖的抗渗透性和抗冲刷性,对高铬砖产生了致命的破坏作用.     

生焦与氧化钙焙烧脱硫反应动力学研究

提出了CaO焙烧生焦脱硫的新方法,考察了焙烧时间、焙烧温度、CaO掺杂比例对生焦脱硫率的影响,利用TG-DSC联合法对样品进行分析,研究了生焦与CaO焙烧脱硫反应的动力学。结果表明,生焦与CaO焙烧脱硫反应活化能E为150.8kJ/mol,指前因子A为6.98×1011 min-1,反应机理函数为f(α)=(1-α)2.54,最佳工艺条件为:焙烧温度1173K,焙烧时间1h,CaO掺杂比例75%;该条件下生焦的脱硫率可达47%,主要产物为CaS、CaCO3。     

气流磨超细粉碎循环流化床锅炉脱硫灰的试验研究

为提高循环流化床燃煤锅炉脱硫灰在工程上的利用率,利用气流磨对循环流化床脱硫灰进行超细粉碎,通过调节分级机频率大小进行分组实验。结果表明:CaO和SO3组分含量在循环流化床脱硫灰中所占比例大,质量分数分别达26.84%和12.25%;采用气流磨粉碎循环流化床脱硫灰,有效地增大了CaO的比表面积,通过调节分级机的频率可获得窄粒度段分布的超细脱硫灰,获得的超细脱硫灰颗粒表面粗糙,凹凸不平,呈不规则形状。     

CaO坩埚在超纯净熔炼Ni基高温合金过程中对脱N的影响

研究了使用CaO坩埚在VIM法精炼Ni基高温合金过程中N的变化规律及加Al对脱N的影响,初步分析了脱N的影响因素及机理。     

一种新牌号Ni基高温合金的超纯净熔炼

研究了在真空感应炉中采用CaO坩埚熔炼一种新牌号Ni基高温合金的效果，结果表明，采用CaO坩蜗熔炼，当熔化期为25min时，O，N的脱除率分别为52％和5％，加入适量的C有利于O，N的去除，加入02％C比没加C时O，N可分别多脱除36％和60％，高温高真空下单纯使用CaO坩埚而无碱性渣不能脱S，加入0．5％Al后经．50min精炼可脱除35％的S。     

醋酸钙/飞灰复合脱硫脱硝剂热解性能实验研究

为了提高脱硫脱硝效率同时合理利用火电厂产生的飞灰,研究了醋酸钙中加入飞灰制备的复合脱硫脱硝剂的热解性能。对不同条件下制得的醋酸钙/飞灰复合脱硫脱硝剂的热重特性、X射线衍射图谱、比表面积、扫描电镜结果等进行了分析,结果表明:利用醋酸钙和飞灰水合制备的脱硫脱硝剂具有比单纯的醋酸钙和飞灰更大的比表面积;经过900℃煅烧后脱硫脱硝剂孔隙结构最好;脱硫脱硝剂经过900℃煅烧后的热解产物(SiO2、Al2O3、Fe2O3和CaO)有助于脱除烟气中的硫氧化物和氮氧化物。     

烧结干法脱硫灰激发高炉矿粉活性及其机理研究

针对烧结干法脱硫灰资源化利用和高炉矿粉早期活性不高的问题,采用烧结干法脱硫灰激发高炉矿粉活性,测试了不同烧结干法脱硫灰掺量下高炉矿粉-水泥体系的强度、干缩、浸水自由膨胀性能;采用X射线衍射、扫描电镜、差示扫描量热-热重法研究了烧结干法脱硫灰激发高炉矿粉-水泥体系的水化产物、微观形貌及其火山灰放热行为机理。结果表明,采用烧结干法脱硫灰激发高炉矿粉能显著提高高炉矿粉3d、7d、28d抗压强度,其原因是高炉矿粉在烧结干法脱硫灰形成的SO42-、CO32-、SO32-环境下,生成了3CaO·Al2O3·CaSO4·32H2O、2CaSiO3·CaCO3·CaSO4·15H2O和3CaO·Al2O3·CaSO3·11H2O等水化产物;烧结干法脱硫灰的掺入使得高炉矿粉-水泥体系出现第三个放热峰,虽峰值相差不大,但出现时间明显滞后,有效减缓了高炉矿粉-水泥体系的水化放热。     

影响脱硫石膏品质的因素及其改善措施

分析了影响脱硫石膏品质的主要因素,重点讨论了烟气中杂质对脱硫石膏品质的影响,并以华电集团下属3家燃煤发电企业脱硫石膏为例,分析了烟气成分中可溶性杂质离子Na＋、Mg2＋、Cl-、F-对脱硫石膏化学组成和微观形貌的影响。论文还讨论了改善脱硫石膏品质的措施。     

镍基高温合金真空感应熔炼脱氮的研究

研究了真空感应熔炼Ni基高温合金过程中的脱氮行为，实验表明在CaO坩埚精炼过程中加Al对脱氮有促进作用，加Ti则对脱氮有明显不利影响，提高熔炼真空度是促进脱氮的有力措施。     

电子束熔炼用水冷铜坩埚研制

电子束熔炼作为一种优异的真空冶炼技术,其核心部件水冷坩埚的结构设计尤为重要,坩埚的冷却性能将直接影响电子束熔炼的效果及安全。通过理论分析、数值模拟、试验考核,研究了坩埚水道结构、熔池形貌对坩埚冷却能力的影响。通过坩埚选材、熔池利用率分析、能量损耗分析和冷却计算确定了坩埚结构,建立了数值仿真模型,采用模拟计算方式对比了两种熔池形貌的坩埚在不同装料量下的冷却性能,并针对性能优异的坩埚开展了试验考核。结果表明：模拟不同锭厚条件下,坩埚B的冷却水温度和坩埚表面温度较坩埚A均偏低,坩埚B的熔池形状和水道结构匹配更合理,散热效果更好。试验考核过程中坩埚B状态稳定,满足设计要求。     

Desulphurization during VIM Refining Ni-base Superalloy using CaO Crucible

The variation of S content during VIM refining Ni-base superalloy using CaO crucible was studied. It was foundthat the desulphurization process could not be carried out by only using CaO crucible. The role of Al additionto desulphurization was also studied. Combining with the results of XRD and composition analysis of the CaOcrucible, the mechanism of desulphurization was proposed. Thermodynamical calculation about the reaction betweenthe interface of CaO crucible and liquid metal has been discussed. This work indicated that under proper refiningtechnology the S content in the liquid Ni-base alloy could be reduced from 3×10-5 to 2×10-6~4×10-6.     

Desulphurization of grain-oriented silicon iron during heat treatment in vacuum

The kinetics of desulphurization has been studied in 0.35 mm thick grain-oriented 3% silicon iron strips with various contents of sulphur (0.007, 0.020 and 0.060% S) and of manganese (0.11 and 0.31% Mn) in vacuum at pressures of 1330 Pa (10 Torr) and 0.0122 Pa (10^?4 Torr), at temperatures of 1150 and 1200°C. The specimens were examined without a coating and, after a previous oxidation, coated with a layer of MgO suspension with and without the addition of 7% Cr₂O₃ and of 0.5% CaO. It was proved that in the course of the vacuum heat treatment of transformer sheets the application of high vacuum is favourable for steel refining. The state of the surface has a considerable influence on the desulphurizing process; an addition of Cr₂O₃ and of CaO to the coating based on the MgO suspension retards the desulphurization process, while without that addition to the MgO suspension the desulphurization process proceeds as of uncoated strips.     

CaO耐火材料的抗热震性能

采用特种粘结剂,控制工艺参数（如粒度配比、成型压力、烧结温度以及ZrO2添加剂含量等）,制备了CaO耐火材料,测量了力学和物理性能。用中心加热法研究了CaO耐火材料的抗热震性能,结果表明,在合适的粒度分布及烧强温度下,添加ZrO2颗粒能显著提高CaO耐火材料的抗热震性能。     

真空感应熔炼中的碳脱氧

应用热力学稳定性好的氧化钙耐火材料,提高精炼温度,强化碳脱氧的热力学和动力学条件,实现了几种金属材料氧的高纯净。     

镍基高温合金脱氧的研究

氧在高温合金中是作为有害杂质元素存在的,通常是疲劳裂纹的萌生地及扩展通道,从而影响高温合金的蠕变、持久强度等性能.本研究在现有条件下,确定了氧在镍基高温合金中存在主要形态为氧化铝夹杂,根据得到的实验数据分析和计算,初步研究了真空感应熔炼条件下碳和铝对镍基高温合金的脱氧机理, 实验中氧含量最低为0.0006%,达到了小于0.001%的目标值.     

Effects of Oxygen on the Microstructure of Ti_(47)Al_(0.7)B Alloys

The effects of oxygen on the microstructure of Ti-47Al-0.7B (at. pct) alloy for as-cast automotive valves were investigated. Six alloys with oxygen content from 0.4 to 1.4 at. pct were prepared by induction melting and centrifugal casting in CaO crucible under protective atmosphere. The microstructures were observed by optical microscopy (OM) and scanning electron microscope (SEM). The results show that the increase of oxygen content led to grain refinement and enhanced the microhardness as well as the α 2 ...     

镍基高温合金用CaO坩埚真空感应熔炼脱氧研究

研究了使用CaO坩埚真空感奕熔炼Ni-6Cr-2Mo-6W-5Co合金过程中碳与氧的变化及加碳和铝的脱氧作用。结果表明，碳脱氧主要表现在熔化期，通常可脱除40％-80％的氧；铝可进一步脱氧至0.0004％-0.0006％。从热力学上计算了镍合金液中C-O，Al-O反应的平衡值。结果表明：C-O反应远未达到平衡，而Al-O反应在1500℃能脱氧至0.0006％以下。     

Evaluation of some self-sustained capillary effects taking place in slag at the interface during desulphurization process

In the paper are presented and analyzed some specific problems of instability and of Marangoni convection in desulphurizing slags at 1873.15 K, due to the presence of sulphur, during liquid steel treatments. Starting from the quantity sulphide capacity, a limit of sulphur solubility in a homogeneous liquid slag is established. The thermodynamic effect of sulphur in the slag is evaluated using an enthalpy of interaction of sulphur containing the balance of the partial molar enthalpy of mixing for CaS and CaO. The sulphur effect in slag, on the enhancement of the mass transfer coefficient through the interface is evaluated based on the expression of the concentration coefficient of the surface tension related to the mole fraction, the solutal Marangoni number and of the sulphur mass transfer enhancement parameters. It is concluded that during desulphurization, self-sustained capillary effects are present in slags.