再生铅低温碱性固硫熔炼的实验研究

针对我国传统再生铅生产工艺所存在的熔炼温度高、能耗大、铅和低浓度SO2烟气污染严重等弊端,在对NaOH-C-PbSO4-ZnO低温碱性炼铅体系进行理论分析的基础上,提出了一种再生铅的低温碱性固硫熔炼新工艺.以废铅酸蓄电池胶泥(以下简称胶泥)为实验原料,采用单因素实验法分别考察NaOH用量、熔炼温度、焦粉用量及固硫剂ZnO用量对金属铅直收率和ZnO固硫率的影响.获得优化实验条件如下：m(NaOH)/m(胶泥)=60%,熔炼温度为860℃,m(焦粉)/m(胶泥)=10%,m( ZnO)=m(理论量).在此优化条件下进行综合扩大实验,铅的直收率为99.09%,获得粗铅品位为98.86%,ZnO固硫率为93.37%. X射线衍射图谱分析可知,反应后原料中硫主要以ZnS的形式固定在渣中,NaOH绝大部分转变为Na2 CO3,生产过程中无SO2气体排放.     

脆硫铅锑矿精矿的还原造锍熔炼

采用富含氧化铁的黄铁矿烧渣作为固硫剂的铅、锑、铋还原造锍熔炼方法,对脆硫铅锑矿精矿还原造锍熔炼的工艺进行了研究,考察了温度、添加剂加入量、烧渣加入量等对还原造锍熔炼工艺的影响,得出最佳工艺条件为:先在900℃下反应,再升温到1200℃过热放渣;烧渣加入量为理论量的100%～105%;添加剂与苏打质量比为10%,无水硫酸钠为13%(质量分数).在最佳条件下,锑直收率为83.26%,铅直收率为68.50%,固硫率为98.97%,但约有15%的铅和30%的银分散在铁锍中.     

含金砷硫精矿烧渣炼铁富集金的研究

提出一种处理含金砷硫精矿的新工艺,主要包括焙烧脱除硫砷—烧渣炼铁富集金—电解分离铁金等工序.对其中烧渣炼铁富集金进行实验研究,研究熔炼中C与O质量比与炉渣二元碱度(即CaO与SiO2质量比)、熔炼温度和熔炼时间对铁和金回收率的影响,确定最佳条件及在此条件下所得生铁的化学成分.研究结果表明:在C与O质量比为0.93、炉渣二元碱度为1.0、熔炼温度为1500℃、熔炼时间为90 min的最佳条件下,铁和金的回收率分别达到97.49％和99.10％,所得生铁中金质量分数为16 g/t,与烧渣金质量分数相比约提高0.63倍,铁质量分数为97.27％,碳质量分数为1.38％.     

硫化锑精矿低温熔炼新工艺

针对我国现行火法炼锑工艺所存在的冶炼温度高、流程长和低浓度SO2烟气污染严重等弊端,提出一种新的火法炼锑工艺——硫化锑精矿低温熔盐熔炼。采用单因素实验法分别考察熔盐组成、熔炼温度、熔炼时间、熔盐量及固硫剂ZnO加入量对金属锑直收率和粗锑品位的影响。获得优化实验条件如下:熔炼温度为850℃,w(Na2CO3)/w(固体物)=5:1,w(Na2CO3)/w(NaCl)=0.75,w(ZnO)/w(理论量)=1.0,反应时间为1 h。在此优化条件下进行综合扩大试验,锑的直收率为84.42%,所得粗锑品位为86.66%。     

多金属氧化钼矿工艺矿物学及其综合利用技术研究

对氧化钼矿的工艺矿物学特征及其综合利用技术进行研究.结果表明:氧化钼矿的主要矿物组成为钼华、钼钙矿、褐铁矿、黄铁矿及石英.在磨矿细度为200目以下含量65%时,采用混合浮选工艺,可得钼品位为7.41%的钼精矿,钼回收率为82.18%,其中含铅18.02%、含金7.96 g.t-1、含银1 002 g.t-1;采用联合碱浸法处理钼精矿,可获得钼浸出率为95.61%的工艺指标;采用氰化法处理碱浸渣,金银浸出率分别为94.55%、83.96%;采用浮选法处理氰化渣,可得铅品位为46.76%的铅精矿,铅回收率为52.83%;采用重选法回收浮选尾矿中的石英,可获得SiO2含量为97.12%、回收率为80.84%的石英产品.     

铜浮渣富集熔炼过程金属分配行为

针对铜浮渣传统火法处理工艺存在能耗高,环保效果差,铅和铜分离不彻底的问题,采用熔池熔炼工艺处理铜浮渣,研究熔池熔炼过程中铁硅比(m(FeO)/m(SiO2))、钙硅比(m(CaO)/m(SiO2))、硫加入量、铁屑加入量、煤粉加入量和碳酸钠加入量对Pb,Cu,Bi,As,Sb和Sn元素分配的影响,并对熔炼产物渣相和锍相的物相组成进行检测。研究结果表明:在m(FeO)/m(SiO2)为1.9,m(CaO)/m(SiO2)为0.6,硫加入量为铜浮渣的3%,铁屑加入量为10%,煤粉加入量为5%,Na2CO3加入量为6%的最优条件下,Pb,Bi和Sb主要进入粗铅中,其在粗铅中的分配率分别为83.43%,99.09%和43.62%,Cu和As主要进入冰铜中,其在冰铜中的分配率分别为44.10%和88.80%,Sn主要进入烟气中,其在烟气中的分配率为78.58%。As易与Fe形成Fe-As相嵌入冰铜相中。     

NaOH-NaNO_3-Air体系低温碱性熔炼处理废弃电路板多金属粉末

研究Na OH-Na NO3-Air体系低温碱性熔炼处理废弃电路板多金属粉末的工艺流程,在熔炼过程中对各因素对两性金属的影响进行系统研究,优化得到较为适宜的熔体组成与工艺条件:Na NO3,Na OH和多金属粉末质量比为0.6:2.5:1.0,温度为350℃,空气流量为1.5 L/min,熔炼时间为30 min。研究结果表明:在此条件下Sn,Pb,Al和Sn的转化率分别为100%,83.99%,93.26%和91.97%。针对含两性金属的碱性浸出液,设计Ca(OH)2沉锡和Na2S·9H2O沉铅锌的分离工艺,得到纯度(质量分数)98%以上的Sn O2及Pb S-Zn O混合物。     

用热重法分析电石渣的固硫性能

用热重法建立一种分析电石渣固硫性能的方法.通过分析电石渣的固硫机理,利用煤燃烧、电石渣热分解和电石渣与煤混合试样的TG曲线计算生成电石渣固硫反应TG曲线,同时通过各试样残留质量间的关系计算出了不同钙硫摩尔比电石渣的固硫效率.结果表明:三种实验条件下,钙硫摩尔比为1.5时,电石渣固硫效果最好.     

“豫光金铅”鼓风炉炼铅渣性能分析研究

检验了"豫光金铅"鼓风炉炼铅渣的化学成分,并测定了其熔点、粘度、密度、表面张力等。通过铅渣物化性质的分析,寻找铅渣含铅高、渣型不稳、流动性不好、渣粘等问题的原因,确定合理渣型,使冶炼工艺正常运行,提高铅的综合回收率。     

低碳含铝钢20Mn2精炼渣系CaO-SiO2-Al2O3-MgO-CaF2的优化

通过对低碳含铝钢20Mn2精炼过程的取样分析,得出精炼渣的熔化温度偏高,渣中存在大量固相CaO,并导致钢中含有CaO类夹杂物,精炼渣吸附夹杂物能力差. 利用FactSage热力学计算,从渣的低熔点区域控制和渣-钢反应这两个方面对渣系进行研究与优化. 结果表明,CaO/Al2 O3 质量比在1. 5左右添加质量分数为3% CaF2 可以有效降低渣的熔化温度,渣的熔化温度随着CaF2 含量的升高呈现先降低后升高的趋势,MgO的质量分数控制5%左右低熔点区域面积达到最大. 在SiO2 质量分数大于30%区域,钢中氧含量大体上随着CaO/Al2 O3 质量比的增加而降低,在SiO2 的质量分数低于30%区域随着CaO含量的升高而降低,钢中酸溶铝含量在SiO2 含量高的区域随着Al2 O3/SiO2 质量比的增加而升高,在SiO2 含量低的区域随着CaO/SiO2 质量比的增加而增加. 根据热力学分析结果得出合理的渣系范围:CaO 50% ~60%, Al2 O3 20% ~35%, SiO2 5% ~10%, MgO 5% ~8%, CaF2 0~5%. 优化渣系的实验结果表明,优化后渣系熔化温度降低,钢中夹杂物数量、面积和平均尺寸均有明显下降.     

Reductive smelting of spent lead-acid battery colloid sludge in a molten Na2CO3 salt

Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing ZnO as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, ZnO and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows:T = 880°C;t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the ZnO dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The re-sults suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic cal-culations indicated that the reaction approaches of lead and sulfur were PbSO4→Pb and PbSO4→ZnS, respectively. Sulfur was fixed in the form of ZnS, whereas the molten salt did not react with other components, serving only as a reaction medium.     

Effect of the CaO/SiO2 mass ratio and FeO content on the viscosity of CaO–SiO2–"FeO"–12wt%ZnO–3wt%Al2O3 slags

An effective process for recycling lead from hazardous waste cathode ray tubes (CRTs) funnel glass through traditional lead smelting has been presented previously. The viscous behavior of the molten high lead slag, which is affected by the addition of funnel glass, plays a critical role in determining the production efficiency. Therefore, the viscosities of the CaO–SiO2–"FeO"–12wt%ZnO–3wt%Al2O3 slags were measured in the current study using the rotating spindle method. The slag viscosity decreases as the CaO/SiO2 mass ratio is in-creased from 0.8 to 1.2 and also as the FeO content is increased from 8wt% to 20wt%. The breaking temperature of the slag is lowered sub-stantially by the addition of FeO, whereas the influence of the CaO/SiO2 mass ratio on the breaking temperature is complex. The structural analysis of quenched slags using Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy reveals that the silicate network structure is depolymerized with increasing CaO/SiO2 mass ratio or increasing FeO content. The [FeO6]-octahedra in the slag melt increase as the CaO/SiO2 mass ratio or the FeO content increases. This increase can further decrease the degree of polymerization (DOP) of the slag. Furthermore, the activation energy for viscous flow decreases both with increasing CaO/SiO2 mass ratio and increasing FeO content.     

二次铝灰低温碱性熔炼研究

研究利用低温碱性熔炼法提取二次铝灰中铝的过程.探讨碱灰质量比、盐灰质量比、熔炼温度、熔炼时间、不同添加剂和不同混料方式等因素对铝浸出率的影响.研究结果表明:优化条件为:碱灰质量比1.3、盐灰质量比0.7(NaNO3)或0.4(Na2O2)、熔炼温度500℃、熔炼时间60 min.湿混料可以提高铝浸出率,以NaNO3为添加剂干混料铝浸出率最高可达87.52％,以NaNO3为添加剂湿混料铝浸出率最高可达92.71％,以Na2O2为添加剂湿混料铝浸出率最高可达92.76％.     

铅闪速熔炼过程的多相平衡模型

针对粗铅、铜锍、炉渣和烟气四相平衡体系,基于最小吉布斯自由能原理,采用元素势法,建立铅闪速熔炼多相平衡热力学模型.在与半工业试验相同炉料组成、熔炼温度、富氧浓度等操作条件下,模拟计算平衡组成.研究结果表明;粗铅中Pb质量分数绝对误差为0.30,相对误差仅为0.30％;炉渣中Pb,CaO和SiO2质量分数绝对误差分别为2.00,0.50和0.70,相对误差分别为6.67％,3.57％和3.89％,说明建立的模型能较好地反映铅闪速熔炼实际情况,为铅闪速熔炼过程的热力学研究提供了依据.     

熔融还原过程硅还原氧化行为

试验研究熔融还原过程条件下SiO2还原氧化行为及对过程的影响。研究表明：喷吹煤粉燃烧温度、煤的灰份组成影响SiO2还原过程。通过适当选择煤种和控制氧煤喷枪的喷吹位置,可以减轻SiO2还原挥发过程的不利影响。     

QSL炼铅过程的热力学分析

根据已提出的直接炼铅过程的计算机模型，分析了ＱＳＬ炼铅法在工业上得不到弃渣而失败的根本原因，同时对精矿成分、熔炼温度、重油量和风量等操作条件进行了模拟，发现提高温度不能得到弃渣，而还原性的气氛却可极大地降低炉渣中铅含量，从而提出降低渣含铅的具体改进措施与方案，为在实际生产中解决这一问题提供可靠的依据．     

Effects of smelting parameters on the slag/metal separation behaviors of Hongge vanadium-bearing titanomagnetite metallized pellets obtained from the gas-based direct reduction process

Smelting separations of Hongge vanadium-bearing titanomagnetite metallized pellets (HVTMP) prepared by gas-based direct reduction were investigated, and the effects of smelting parameters on the slag/metal separation behaviors were analyzed. Relevant mechanisms were elucidated using X-ray diffraction analysis, FACTSAGE 7.0 calculations, and scanning electron microscopy observations. The results show that, when the smelting temperature, time, and C/O ratio are increased, the recoveries of V and Cr of HVTMP in pig iron are improved, the recovery of Fe initially increases and subsequently decreases, and the recovery of TiO₂ in slag decreases. When the smelting CaO/SiO₂ ratio is increased, the recoveries of Fe, V, and Cr in pig iron increase and the recovery of TiO₂ in slag initially increases and subsequently decreases. The appropriate smelting separation parameters for HVTMP are as follows: smelting temperature of 1873 K; smelting time of 30–50 min; C/O ratio of 1.25; and CaO/SiO₂ ratio of 0.50. With these optimized parameters (smelting time: 30 min), the recoveries of Fe, V, Cr, and TiO₂ are 99.5%, 91.24%, 92.41%, and 94.86%, respectively.     

铝在碳酸钠溶液介质中的缓蚀研究

在0.1mol/L Na2CO3溶液中用失重法研究K2CrO4、Na2SiO3溶液及两者混合液对铝的缓蚀作用，在0.1mol/L Na2CO3溶液中分别添加浓度为0.01～0.05mol/L的K2CrO2和0.01～0.10mol/L的Na2SiO3，铝的缓蚀率分别为91.4%～95.0%和91.4%～97.1%，K2CrO4的适宜浓度是0.03mol/L，Na2SiO3的适宜浓度是0.08mol/L，在添加0.01mol/L的K2CrO4与0～0.04mol/L的Na2SiO3混合液条件下，铝的缓蚀率为91.4%～99.5%，其中0.01mol/L K2CrO4与0.02～0.03mol/L Na2SO3的两种混合液均使缓蚀率达到98%以上，比单一缓蚀剂的效果好。     

THE EFFECT OF DIFFERENT STABILIZERS ON ALKALINE H2O2 BLEACHING OF NS REED PULP

This paper uses a new stabilizer of H2O2 bleaching and compares the stabilizing effect of the new stabilizer with that of Na2SiO3. The results show that the new stabilizer is better than the conventional Na2SiO3. The optimum conditions of the stable latter process bleaching of H2O2 as follow: NaOH 3%,MgSO4 0.05%, H2O2 3%, stabilizer 3%, temperature 80℃, concentration 12%, time 3h.