宝钢含锌尘泥的循环利用工艺简介

对宝钢的含锌尘泥(转炉二次粉尘、电炉粉尘和高炉瓦斯泥)的厂内循环利用进行了研究,通过将含锌尘泥分别应用于铁水三脱、转炉造渣和电炉造泡沫渣工艺对循环利用工艺进行了试验,具体如下:将转炉二次粉尘和电炉粉尘的混合物取代烧结矿粉作为铁水脱磷剂,通过改善流动性,达到了与烧结矿粉相当的脱磷效果,在三脱处理中粉尘中的锌和铅含量得到了明显的富集,为下一步回收处理打下了基础.将转炉二次粉尘和电炉粉尘的混合物通过添加一定量生白云石和锰矿加工成冷压块,在转炉吹炼前期加入,促进了石灰的溶解,改善了前期化渣,提高了脱磷率,LT压块和矿石的耗量减少.造渣剂加入没有引起钢水的增硫明显,粉尘造渣剂的加入对钢水和炉渣成分没有影响.将高炉瓦斯泥通过添加一定量生石灰和生白云石并加工成冷压块后,在电炉熔炼期加入,强化泡沫渣操作,减少金属损失和碳粉用量.瓦斯泥压块加入后对钢水、炉渣成分和电炉的粉尘不会产生明显影响.     

45t电炉终点碳控制技术研究与应用

对45 t电炉终点碳控制技术进行研究,优化了冶炼工艺及用氧制度,改进了泡沫渣工艺.电炉氧化末期钢水碳的合格率得到较大提高,减少了脱氧材料加入量,在一定程度上降低了LF座包钢水中的氧含量.通过优化泡沫渣工艺,电炉炉盖结冷钢现象已基本杜绝,炉子水冷件漏水现象大幅度减少,缩短了热停时间.     

信息报导

炼钢 废钢质量评估 本文介绍了采用不同的炼钢工艺,尤其是电炉炼钢工艺对废钢质量的确定方法,并对其进行了核定试验。 摘自《南钢科技》1996.2 钡系多功能泡沫渣应用研究 分析了钡系多功能泡沫渣的作用机理,通过试验应用,得出了该材料在电炉冶炼中制造泡沫渣和强化脱磷方面的效果。     

电炉粉尘循环利用造泡沫渣

在实验室中研究了电炉粉尘和煤粉加入量及温度对泡沫渣高度的影响.结果表明,在电炉渣中加入0~30%的电炉粉尘和3%~12%的煤粉(质量分数)时,随粉尘及煤粉加人量的增加以及温度的提高,泡沫渣的最大发泡高度增加;在加入电炉粉尘造泡沫渣过程中,随温度升高,渣中ZnO的还原挥发速度加快,反应6 min,Zn的挥发率大于97%.在本实验条件下,反应3min,渣中Pb小于0.02%,温度对PbO的还原挥发速度无明显影响.     

电弧炉中泡沫渣稳定性影响因素

通过向电弧炉中喷吹炭粉和氧气，进行泡沫渣炼钢操作，可降低电炉单位电功率消耗。提高炉渣中的ＦｅＯ含量，使ＦｅＯ和加入沥青焦炭提供的炭反应生成ＣＯ气体，形成泡沫渣。此吸热反应，可降低炉渣温度，加快Ｃａ２ＳｉＯ２的析出，提高炉渣的粘度，从而提高泡沫渣的稳定性。     

在电炉中使用硝酸钙所形成的不锈钢泡沫渣

Steelcal(一种特殊的硝酸钙)作为电炉中熔炼不锈钢的一种炉渣发泡剂，人们最近对其进行了测试。当Steelcal和碳一起加入炉渣中时，Steelcal分解出的CaO和C反应生成CO和其他气体，这有助于炉渣的发泡。在德国某钢厂进行了该实验并成功获得泡沫渣。泡沫渣的高度和各种泡沫渣形成的时间     

含铁尘泥压块高温强度劣化规律及机制

摘要：基于Oxycup工艺,以高炉工序的重力除尘灰和转炉工序的转炉污泥作为主要原料,配加一定量的粘结剂制成复合压块,通过开展模拟实验和基础分析,研究含铁尘泥压块强度的劣化规律和劣化机制。结果表明：水泥粘结剂的加入能有效抑制含铁尘泥压块的体积膨胀,稳定含铁尘泥压块的内部结构,从而保证含铁尘泥压块的高温强度;水泥粘结剂压块的致密度要高于羧甲基纤维素钠粘结剂压块,且在水化过程中会生成氢氧化钙,会对铁氧化物还原起到一定的促进作用,从而使得水泥粘结剂压块的还原性强于羧甲基纤维素钠粘结剂压块;水泥粘结剂压块由于水泥石相固结作用的存在,使压块强度有了显著的提高,随着温度的提高,水泥粘结剂逐渐失效,但失效后的水泥石仍能保持一定原始形态,能够稳定压块的内部结构,使压块强度劣化的同时仍能保持一定的基础强度。     

含铁尘泥压块高温强度劣化规律及机制

基于Oxycup工艺,以高炉工序的重力除尘灰和转炉工序的转炉污泥作为主要原料,配加一定量的粘结剂制成复合压块,通过开展模拟实验和基础分析,研究含铁尘泥压块强度的劣化规律和劣化机制。结果表明:水泥粘结剂的加入能有效抑制含铁尘泥压块的体积膨胀,稳定含铁尘泥压块的内部结构,从而保证含铁尘泥压块的高温强度;水泥粘结剂压块的致密度要高于羧甲基纤维素钠粘结剂压块,且在水化过程中会生成氢氧化钙,会对铁氧化物还原起到一定的促进作用,从而使得水泥粘结剂压块的还原性强于羧甲基纤维素钠粘结剂压块;水泥粘结剂压块由于水泥石相固结作用的存在,使压块强度有了显著的提高,随着温度的提高,水泥粘结剂逐渐失效,但失效后的水泥石仍能保持一定原始形态,能够稳定压块的内部结构,使压块强度劣化的同时仍能保持一定的基础强度。     

沸煮法处理平炉及电炉渣工艺条件研究

通过现场试验,验证了沸煮法处理平炉及电炉渣的可行性,利用正交试验得出了沸煮法处理上海第三钢铁厂平、电炉渣的最佳工艺条件。     

20t EBT电炉喷粉造泡沫渣试验

石横特殊钢厂在２０ｔＥＢＴ电炉上采用以喷粉造泡沫渣工艺代替过去用锨加入炭粉造泡沫渣工艺,解决了氧化期埋弧效果差、提温困难等问题,冶炼电耗降低１０ｋＷ·ｈ／ｔ、冶炼时间缩短２～３ｍｉｎ,电弧辐射和噪音明显减小。     

转炉锰矿直接合金化生产实践

在100 t顶底复吹转炉上使用锰矿自还原压块进行直接合金化工业试验中,并对冶炼过程中钢水和炉渣进行取样分析。研究表明:在采用锰矿自还原压块进行转炉直接合金化时,金属锰的收得率平均为65.17%,但有较大波动;提高转炉终点[C],减少转炉渣量,降低炉渣氧化性可有效提高金属Mn的收得率;当按15 kg/t配入团块,转炉终点温度平均降低18℃,未对转炉的正常冶炼造成影响。     

EAF Smelting Trials of Waste‐Carbon Briquettes at Avesta Works of Outokumpu Stainless AB for Recycling Oily Mill Scale Sludge from Stainless Steel Production

The EAF steel plant of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 t of briquettes or 3.4 mass‐% of metal charges. The quantities of FeSi powder and O₂ gas injected and electric energy supplied were increased to smelt briquettes of 6 t. No impacts were found on the analyses of the crude stainless steel tapped from the EAF during the trials. The results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from earlier laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. The slag masses were not increased in three trials as compared with the reference heats. There were moderate increases in the slag masses in four trial heats. The increases were, nevertheless, lower by 52‐69% than the slag masses generated by Sireduction of the briquette oxides. Afterwards, by referring results from the present trials, waste‐carbon briquettes amounting to 1‐3 t were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production.     

不锈钢粉尘内配煤团块高温自还原过程中金属铁的聚集

用不锈钢生产中的高碱度二次粉尘制备内配煤团块,在高温下自还原获得含铬、镍的金属铁粒.研究影响铁粒聚集长大的因素.研究表明:(1)内配煤团块的渣相碱度(w( CaO)/w( SiO2))小于2.8时,还原产物冷却过程中渣相与金属铁粒才能自然分离.碱度越低,渣量越大,越不利于金属铁聚集长大;(2)提高内配碳比,渣相残碳量明显升高,渣中过量的碳阻碍金属相聚集长大;(3)提高还原温度,直接还原铁的海绵状结构解体,逐渐聚集成颗粒状金属铁.还原温度越高,越有利于金属铁的聚集长大     

含锌粉尘冷固结团块高温自还原过程分析

摘要：对含锌粉尘冷固结团块进行高温焙烧,研究了配碳量和焙烧温度对团块自还原过程的影响。结果表明,团块焙烧后的抗压强度随着焙烧温度的升高呈现先降低后增加的趋势,焙烧温度为900℃时,团块的强度降到最低。不同配碳量的团块焙烧后的抗压强度随焙烧温度增加的趋势也不同,配碳量低的团块抗压强度增加的趋势较强。焙烧温度超过900℃后,团块的金属化率显著增大,团块的体积开始收缩,且焙烧温度越高,团块体积收缩的程度越大,而配碳量低的团块体积收缩程度更大。团块中会形成少量含FeO的低熔点渣相,并在高温下融化成液态,有利于团块体积的收缩,减少了孔隙,促进了团块内金属铁连晶结构的形成。     

TiO2对合成渣中Fe2O3还原发泡过程的影响

研究了不同条件下TiO₂和Fe₂O₃在合成渣中被碳还原时的发泡过程.计算了该发泡过程的发泡系数、消泡系数、平均发泡寿命、发泡强度和消泡过程开始的时间.用熔渣发泡参数定量地讨论了温度、TiO₂加入量和初渣中TiC的含量对熔渣发泡过程的影响,发现当初渣中TiC的含量和TiO₂加入量较多时,在发泡时会产生二次发泡现象.     

原位合成多孔凝渣材料机理研究

含钛高炉渣特殊的物理化学性质是产生多孔凝渣层的基础条件,在降温过程中黏度提高很快,气泡被迅速“冷冻”;高熔点TiC、TiN及其固熔体Ti(C,N)的存在,显著降低了熔渣的表面张力,使炉渣黏度增加、变稠,阻碍渣中气泡的长大和放出;含钛高炉渣中TiO2组分,尤其是以四配位离子团存在的阳离子Ti4+,其增加熔体黏度、稳定泡沫的作用明显;TiO2及其高熔点还原产物是表面活性物质,具有稳定气泡的马拉戈尼效应。多孔凝渣层的形成是由于反应物质产生气体,气体上浮逸出的速度小于气体生成的速度,以及渣急速冷却凝固,使部分气泡“冷冻”存留在凝渣中。     

Foaming and the Rate of the Carbon-Iron Oxide Reaction in Slag

Foaming in the electric arc furnace is achieved by injecting carbon into slag, where the resulting reaction of the carbon with FeO dissolved in the slag generates gas (CO) that causes the slag to foam. In this research, the rate of the reaction of FeO in slag with carbon and the resulting foam height were measured. In these experiments, the FeO content of the slag ranged from 15 to 45 mass pct, and several different types of carbon were used including graphite, coals, and chars. The rate of the slag-carbon reaction and the consequent CO generation increased with FeO content of the slag from 15 to 45 mass pct. However, the slag foam height reached a maximum at about 25 mass pct FeO and decreased at higher FeO contents. The decrease in foaming is apparently due to a decrease in the foam index or foamability caused by a decrease in viscosity and an increase in density of the slag with FeO content. The results of this work indicate that the foam height is influenced more significantly by the decrease in the foam index compared to the increase in the CO gas generation rate at higher FeO contents. The decrease in the foam index with FeO agrees with that predicted from the slag properties.     

高碱度内配煤含铁团块自还原过程中脱硫和脱磷

以转炉除尘灰、高炉瓦斯灰和硫酸渣为含铁原料,制成CaO/SiO₂值为2.0、C/O摩尔比为1.1～1.2的高碱度内配煤含铁团块,在1330～1380℃下进行自还原,研究这一过程的脱硫和脱磷规律.结果表明:(1)高碱度内配煤含铁团块自还原过程中,通过还原气化脱硫可去除20%～40%的硫,其余的硫绝大部分存在于渣中,并通过渣铁分离被去除,总脱硫率高于97%.(2)过量的CaO可以抑制脉石中的P₂O₅被碳还原,已被还原的磷一部分被新生态的金属铁吸收,另一部分从团块内部逸出而去除.脉石中未被还原的P₂O₅最终可通过渣铁分离被去除,总脱磷率达到50%～60%.(3)高碱度内配煤含铁团块高温自还原法可制备出低硫、低磷的\     

Additions to generate foam in stainless steelmaking

Foaming of stainless steelmaking slags is difficult because the gas-generation rate is normally low. In the present work, the impact of reducible oxides (such as NiO by carbon), waste oxide briquettes, limestone, and calcium nitrate on foaming was examined. Specifically, the gas generation rates and the rate-controlling mechanisms for each of these additives were determined. From these results, the expected foaming in actual steelmaking operations can be predicted. The NiO and carbon additions do not appear practical for generating foam. However, limestone, calcium nitrate, and possibly waste oxide briquettes should provide significant foaming.     

Formation and effects of slag foaming in smelting reduction

Research was carried out on the foaming phenomenon in the bath of the smelting reduction process with a hydrodynamic model and with high-temperature experiments. There are two mechanisms of slag foaming: when foam is generated by injected gas, the height of the slag foaming can be regulated. Contrarily, the production of gas during the reduction of iron oxides causes slag foaming which can hardly be controlled. High temperature as well as low slag basicity reduce the foam stability. In smelting reduction a large slag volume is expected. A rinse-spot in the slag layer, which can prevent slag foaming, disappears under these conditions. Wall-effects play an important role for the foam stability.