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1.
Computer simulation of the preparation process loading rare earth(RE)directly from acidic extractant and RE chloride was established using MATLAB software.The mechanism of the extraction reaction was assumed,and then an experiment was conducted to confirm the mechanism and the apparent equilibrium constant of the reaction was determined as well.Owing to the involvement of H+ ion in the reaction between acidic extractant and RE chloride,the computer simulation of the process was more complicated than that of the extraction only between different rare earths.In the present work,MATLAB software was therefore introduced to handle the resolution of the complicated processing equation,and the simulation was performed by varying some key parameters including feed composition and phase ratio,etc.Consequently this work presented a simple method to simulate the H+ ion involved countercurrent extraction process of rare earths and also provided the practical references for the relative process designing.  相似文献   
2.
For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent (Smin) and minimum amount of scrubbing agent solution (Wmin) were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/BC separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/C pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic and the aqueous phase at steady state were given by computer simulation.  相似文献   
3.
ApplicationofthePhaseTransferCatalysisinRareEarthSolventExtractionYanChunhua(严纯华);ZhangYawen(张亚文);LiaoChunsheng(廖春生);JiaJiang...  相似文献   
4.
冕宁氟碳铈矿除氟萃取铈(Ⅳ)工艺研究   总被引:1,自引:0,他引:1  
本文研究了冕宁氟碳铈精矿加分解助剂进行焙烧时的温度、时间及分解助剂用量对稀土提取率的影响。研究了对焙烧矿进行水洗除氟过程中水温、洗涤次数、AlCl3加入对除氟效果的影响以及硫酸浸取除氟矿时硫酸浓度、酸浸时间对稀土提取率的影响。讨论了P204皂化度、浓度、料液中Ce(Ⅳ)的浓度、酸度对Ce(Ⅳ)萃取分配比的影响以及萃取络合物形式、萃取平衡时间等。  相似文献   
5.
随着市场化经济不断加强后,图形广告设计也是越来越频繁,而图形创意是广告设计作品的表现形式,在设计作品中敏感和备受注目的视觉中心,并且优秀的广告作品都是以自己独特的图形语言准确,而且又清晰地表达设计的主题。创意的图形表现基本上都是通过对创意的中心的深刻思考和系统分析,达到充分发挥想象思维和创造力,将想象、意念形象化、视觉化的效果,本文将对图形创意在广告设计中的灵魂意义进行讨论,以此提高图形创意在广告中的设计表达意义。  相似文献   
6.
Impurity components decrease stage by stage in a cascade of rare earth (RE) extraction separation, and adjacent stage impurity ratio (ASIR) which is defined as the ratio of an impurity’s contents in the aqueous/organic phase of two adjacent stages can be used to evaluate the capacity of impurity removal for the two stages. On the basis of extraction equilibrium and mass balance, the ASIR in a two-component extraction separation was deducted and its simplified expressions were given for different process sections according to reasonable assumptions. The calculation simulation was then carried out to obtain the ASIR distribution in the cascade. The results showed that in both the extraction and scrubbing sections the ASIR principally increased with the decrease of the molar proportion of the impurity but along with a flat appearing in the purification zone located in the middle of the cascade. The ASIR intuitively exhibits the running status of RE extraction separation and purification, which could provide a theoretic guide for investigating the influence factors of RE extraction separation process in practical industry.  相似文献   
7.
概况 稀土在铸造钢铁中的应用,是我国稀土应用量最大的行业。其应用量占国内稀土应用总量的1/3左右,且每年都在5~8%的递增。以氧化物计算年消耗稀土约2.5万吨。产品主要为稀土硅铁和稀土镁硅铁。载至加2006年底初步估计:稀土硅产量5万吨左右(其中四川省1.4万吨左右,内蒙古2.2万吨左右,山西0.5多万吨左右,河南0.4万吨左右,其它地区0.5万吨左右)由稀土硅转化为稀土镁产量约18万吨上下,稀土硅出口约05万吨、稀土镁出口(包括配有稀土的多类球化、变质、孕育剂)不会少于5万吨上下。其生产的主要原料稀土精矿主要采用四川攀西稀土矿。也有少量配以包头矿厂家。  相似文献   
8.
研究车牌准确定位识别的问题,交通流量在高速条件下识别系统采集信息与数据有差异,同时在复杂背景中由于车牌的纹理区域面积太小造成车牌定位困难,传统的识别算法由于模板以及方向的选择困难,造成文字的识别率低的等问题.为解决上述问题,提出了一种利用数学形态学操作提取车牌和基于神经网络算法的车牌文字识别技术.首先将汽车图像进行边缘提取处理,提取候选区域,依据各个候选区域特性,进行形态学操作,从而可提取车牌图像,同时利用神经网络对车牌图像中的文字进行识别.实验结果显示改进的方法快速有效地提取车牌图像的边缘信息,所提取的车牌图像与真实车牌的位置吻合,提出的改进方法为车牌识别提供了参考.  相似文献   
9.
廖春生  郝奇  张响亮 《建筑施工》2020,42(8):1491-1493
结合广东台山核电站的施工实践,研发应用了预应力新型触变浆体灌浆工艺。该灌浆工艺采用"触变浆体加真空辅助"的方式,通过控制触变浆体的黏稠度这一重要指标,使浆体性能在满足泵送流动性的同时,仍能具有良好的黏稠度,保证浆体在弧形管道的高点位置及下行段处不易流坠,不会形成孔隙,从而具有良好的充填效果。  相似文献   
10.
Solvent extraction based on mixer-settler is the major industrial method of rare earth (RE) separation. In the mixer-settler extraction process, due to the insufficient settling time in normal circumstances, backmixing of the aqueous phase could have significant impact on the process of RE extraction separation. Therefore on the basis of the extraction equilibrium and mass balance of the mixer-settler extraction process, here we developed a mathematic expression of the aqueous phase backmixing in a two-component separation process, and obtained a quantitative analysis of the backmixing effect on the purification process by the approximations according to certain hypotheses. Two extraction systems of La/Ce and Pr/Nd separation were chosen as the examples to analyze the backmixing effect, and the results showed that the aqueous backmixing had greater influence in the scrubbing segment than in the extraction segment, especially in the system with a high separation factor such as La/Ce separation. Therefore it was suggested that the aqueous backmixing effect should be well attended in the design and application of RE extraction separation.  相似文献   
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