流态化制取三氧化二钒研究

对采用流态化技术,还原多钒酸铵(APV)制取三氧化二钒工艺及相关参数进行了研究,得到了合格的三氧化二钒产品.试验表明: APV在还原温度700～750 ℃、保温时间10～15 min的条件下可以得到TV≥63%的三氧化二钒产品,比回转窑方法所需时间短、温度低;更容易实现对温度和时间的控制,得到较高品位的三氧化二钒产品(TV>67%);流态化生产的三氧化二钒产品C含量低,更有利于钒铁冶炼对C含量的控制;同时,流态化生产三氧化二钒效率高、还原剂消耗少、设备固定、相对安全性更高.     

V_2O_3产品中硫含量影响因素研究

对采用焦炉煤气还原多钒酸铵(APV)制取V_2O_3产品中S含量的影响因素进行了研究,得到了不同S含量的V_2O_3产品。试验结果表明:在APV硫含量0.55%、还原温度800℃、还原时间20 min、煤气流量20 L/h的条件下能够得到S≤0.04%的V_2O_3产品。通过降低APV的S含量、还原过程中翻动物料和对温度、时间的控制可以得到S含量更低的V_2O_3产品。在实际生产中,可以通过调节APV的洗涤程度,控制还原温度和时间,得到不同S含量的V_2O_3产品,满足不同钒合金生产要求,达到节约成本的目的。     

高纯偏钒酸铵的制备技术研究

从生产流程、工艺过程控制参数选取等方面分析了偏钒酸铵产品中杂质含量偏高的原因.研究了APV在不同温度条件下,过滤杂质含量的变化趋势,除杂系数的调整,碱性沉钒铵盐的选择以及沉淀加铵系数等重要参数对杂质含量控制的影响.通过先运用低铵盐沉钒制取多钒酸铵、再返溶除杂净化、最后碱沉的工艺流程,有效地将Cr、Si、Al等主要杂质含量由原来的0.05％以上降低至目前的0.02％以下,对攀钢现有高纯钒生产技术的提高具有重要的指导意义,为攀钢钒业新产品的开发奠定了基础.     

提高酸性铵盐沉钒质量的探讨

针对酸性铵盐沉钒生产过程,优化了工艺参数和控制手段,为生产高品位的V2O3提供优质的原料。主要讨论了含钒浸出液浓度、铵盐加入量、沉钒温度、反应时间、pH值、搅拌条件及板框压滤过程中洗涤条件等因素对酸性铵盐沉钒法制备的多聚钒酸铵(APV)质量的影响。结果表明:含钒浸出液钒浓度为25～35 g/L,采用两次加酸工艺,沉淀终点温度95℃,沉淀反应时间约35 min,APV滤饼洗涤时间20 min,洗涤水温度在75℃左右,压榨吹风时间80 min,风压≥0.5 MPa,滤饼厚度≤25 mm等工艺条件下,可降低沉淀产物多聚钒酸铵的杂质含量,从而提高产品质量。     

铵盐沉钒过程产物形貌控制技术研究

采用酸性铵盐沉钒工艺沉淀多钒酸铵,研究了钒液浓度、沉淀pH值、铵盐加入量、沉淀时间、沉淀温度对沉淀产物多钒酸铵(APV)形貌的影响。结果表明:在沉钒pH=2.2,加铵系数K=2.3,70℃以上反应30 min即可获得球形的APV产品,且沉钒率99%。稳定试验结果验证了沉钒条件的可靠性,通过APV产品形貌的控制,可获得高品质APV产品,且保持较高的钒收率。     

还原工艺对V2O3产品中TV的影响研究

对采用工业煤气还原多钒酸铵（APV）制取V₂O₃工艺及相关参数进行了研究,得到了合格的V₂O₃产品。试验表明:APV在还原温度700～750℃、保温时间10～15min的条件下能够得到TV≥63%的V₂O₃产品,还原温度>750℃、还原时间15min条件下,能够得到TV>65%的V₂O₃产品。通过对温度和时间的控制,可以得到较高品位的V₂O₃产品（TV>66%）。在实际生产中,可以通过对还原温度、还原时间的控制,得到不同TV含量的V₂O₃产品,以满足钒铁冶炼和氮化钒生产对V₂O₃产品中TV的不同要求。     

多钒酸铵熔化过程中钒损失的分析

对多钒酸铵(APV)的物料性质、熔化过程、熔化特点及温度控制等进行了分析,对熔化过程中的钒损失形态及操作工艺进行了讨论,并根据研究结果,采取了有效措施,使APV熔化过程中的钒回收率提高到了97.25%.     

多钒酸铵熔化过程中的钒损失分析及对策

本文对多钒酸铵（APV）的物料性质、熔化过程、熔化特点及过程温度控制等进行了研究分析,对熔化过程中的钒损失形态及操作工艺进行了分析讨论,并根据研究结果采取了有效的对策,应用后取得了明显的效果,APV熔化过程中的钒收率提高到了97．25％。     

炼焦煤微波干燥试验研究

通过不同微波功率、不同水分条件、不同粒度等级等因素变化,对微波干燥炼焦煤效率的影响进行初步研究.结果表明,高功率微波干燥炼焦煤干燥效率高,炼焦煤的起始水分较大、粒度等级较大时干燥效率较高.因此,微波干燥技术更适合对高水分的炼焦煤进行调湿.     

提高酸性铵盐沉钒效果的研究

以江西某地含钒石煤经焙烧-水浸-离子交换所得的富钒液为对象, 研究了加酸加铵方式、添加晶种以及产品洗涤方式对酸性铵盐沉钒制备多聚钒酸铵(APV)的影响. 结果表明: 冷态下采用2次加酸1次加铵、加铵pH值为5左右的方式沉钒有助于提高沉钒效果, V_2O_5纯度可达99%以上; 低浓度含钒溶液沉钒时, 按其生成APV质量的1/200加入晶种破坏溶液过饱和度, 可将沉钒时间缩短25%; 得到的沉淀物经液固比为40∶ 1的自来水洗涤, 能将APV中Na~+, K~+含量降至0.24%, 且钒损失率仅为0.2%.     

Complex Permittivity and Microwave Absorption Properties of Zinc Oxide Leach Residues

Cylindrical cavity perturbation method was used to measure complex permittivity of zinc oxide leach residues (ZOLR) at frequency of 2.45 GHz. The results indicate that both dielectric constant and Loss factor of ZOLR increased with increased of temperature and moisture content. The research of ZOLR’s microwave absorption properties were performed based on reflection loss (RL) theory. Microwave absorption peak of ZOLR moves towards higher material thickness with decreasing of moisture content. However, microwave absorption peak of ZOLR moves towards smaller material thickness with increasing of temperature. RL of ZOLR sensitively depends on material thickness of itself. If want to keeping microwave absorption properties of ZOLR greater than 90% in the process of microwave drying, 10 mm, 40 mm, and 50 mm should be selected as the optimum material thickness.     

Iron ore pellet drying assisted by microwave: A kinetic evaluation

Drying is a critical process step to achieve excellent pellet quality in pelletizing process. The complexity and energy consumption toward moisture removing, especially for highly hydrated iron ore, increased the need for breakthrough enhancements to this process. The present study has evaluated kinetics parameters of the moisture release from iron ore green pellet using energy transmitted through microwave (frequency of 2.45 GHz). The influence of pellet size and output power on the moisture effective diffusivity (D_eff) and the drying activation energy (E_a) were evaluated. The results make possible to compare the cutting-edge approach with traditional convective drying. Pellet physical quality was investigated through the green crushing strength (GCS), which shows smooth reduction in earlier stages, however not affecting the final dry GCS results. Bonded hematite reduction and calcination of goethite was identified at the microstructure through reflected light microscopy, SEM showed micro cracks formation in several grains.     

响应曲面优化微波干燥铅渣的工艺研究

采用微波加热技术对铅渣进行脱水。通过响应曲面法中心组合设计分析了干燥温度、干燥时间、物料厚度对脱水率的影响,并建立了相关的数学模型。方差分析表明,二次方数学模型拟合较好,物料厚度、干燥温度对脱水率的影响较干燥时间更为显著。优化工艺参数为干燥温度93℃,干燥时间10min,物料厚度19mm,相对脱水率达到68.21%,实际值与模型预测值相差0.73个百分点,干燥后铅渣的含水量为8.12%,可以满足后序工艺要求。     

微波干燥在锂离子电池材料生产中的应用

介绍了微波干燥的原理、特点和设备组成,并与传统干燥技术相比较,研究和分析了微波干燥技术在锂离子电池材料生产中的优势。结果表明,经微波干燥处理后,锂离子电池材料的前驱体磁性异物引入量大大降低,分散性好且无团聚现象,与传统干燥前驱体的X射线衍射物相无明显差异,干燥效率提高,一次成品率显著提升。微波干燥技术成功解决了锂离子电池材料磁性异物引入量高、干燥不均匀、分散性差、易团聚等问题,有利于锂离子电池材料的工业化生产。     

微波技术在氢氧化铌干燥中的应用

简要介绍了微波技术特点及微波设备的工作原理,研究了微波加热干燥工艺条件与氢氧化铌含水量、物料粒度的相关性,分析了微波干燥技术的经济性.该工艺技术应用于氢氧化铌干燥,达到了清洁生产和节能环保的效果.     

Comparative study of methods of drying mycelial waste

Two types of apparatus recommended for drying paste-like products, i.e. a continuous-belt film drier and a spouting-bed drier were tested to choose a process for drying mycelial waste. The laboratory studies with the use of the continuous-belt film drier confirmed that a dry moulded product with the moisture content of less than 5 to 6 per cent could be obtained in such an apparatus. In the laboratory and pilot plant studies with the use of the spouting-bed drier equipped with a specially constructed granulator the technological conditions of the drying were defined. The conditions provided stable hydrodynamic drying and obtaining of a dry product with the moisture content of 5 to 6 per cent. Preliminary dried and ground mycelial waste of the tetracycline and rifampicin manufacture is useful as a dry additive in the preparation of the paste with the required moisture content.     

Modeling of Moisture Loss in Cementitiously Stabilized Pavement Materials

The paper presents a theoretical and experimental approach for the modeling of moisture loss during the drying of cementitiously stabilized pavement materials containing varying contents of fine-grained soil. The process of moisture loss was characterized by the isotropic nonlinear diffusion theory. Laboratory tests were undertaken using general purpose Portland cement and two binders comprising industrial waste products. Measurement of material characteristics included the coefficient of moisture diffusivity and the humidity isotherm. Locally available basaltic crushed rocks and clay were respectively used as the host pavement material and fine-grained soil. Independent laboratory tests were undertaken to validate the adopted theoretical approach, which showed close agreement between the experimental and predicted results. The laboratory results indicated that moisture loss decreased with the inclusion of clay soil within the mix. As the drying progressed, the rate of moisture loss became slower, which can be explained by the reduction in the coefficient of moisture diffusivity with the decrease of moisture content.     

微波快速测量高炉喷吹煤粉水分的新方法

研究了用微波快速测量高炉喷吹煤粉水分的新方法，并详细地分析和讨论不同高炉喷吹煤粉水分含量对检测结果的影响。实验结果表明，当含水量为0．74％～16．90％时，检测误差小于0．35％；当含水量为0．31％。1．49％时，检测误差小于0．16％。说明了用微波快速测量高炉喷吹煤粉水分的方法是可行的。     

微波在制备ZAO纳米粉体中的应用

研究了用微波技术制备纳米ZAO粉体的方法以及在微波干燥过程中微波功率和辐射时间等工艺参数对粉体的影响,用TG-DSC对ZAO粉的前驱体进行温度制度的确定.实验结果表明:微波干燥功率700 W,微波辐射时间10 min,煅烧温度550～650℃为佳.     

神东烟煤水分对其高炉喷吹性能的影响

神东烟煤具有水分含量高的特征,这对其生产、运输、储存或用于高炉喷吹都会有影响。针对神东烟煤的这个特性,选用5种不同矿区的具有代表性的高水分神东烟煤,探究不同干燥时间条件下水分对其可磨性的影响,并使用高炉喷煤燃烧模拟试验装置研究其燃烧率随水分含量的变化趋势,将不同条件下的失水质量分数与分析水质量分数的比值定义为失水率,探究可磨性和燃烧率与失水率的变化关系。结果表明,失水率增大时,煤的可磨性和燃烧率均呈上升的趋势,随着干燥时间的延长,可磨性增大的趋势变缓,随着失水的增多,燃烧率和失水率近似呈线性增长的关系。