浸没循环撞击流反应器极具应用潜力的液相和液固相反应装置

理论分析和实验研究结果表明, 浸没循环撞击流反应器（ＳＣＩＳＲ） 与传统的搅拌槽反应器（ＳＴＲ） 相比,虽然在可测量尺度上的混合特性并不占优;但由于撞击区中流体元间剪切速率更高,因而微观混合更强烈。这对于在分子尺度上进行的化学反应具有重要意义。制取“超细”白炭黑研究的结果佐证了ＳＣＩＳＲ强化微观混合的特性。除此以外, ＳＣＩＳＲ在结构方面还具有多项胜过ＳＴＲ的优点, 极具开发应用的潜力。     

浸没循环撞击流反应器——极具应用潜力的液相和液固相反应装置

理论分析和实验研究结果表明,浸没循环撞击流反应器（ＳＣＩＳＲ）与传统的搅拌槽反应器（ＳＴＲ）相比,虽然在可测量尺度上的混合特性并不占优;但由于撞击区中流体元间剪切速率更高,因而微观混合更强烈。这对于在分子尺度上进行的化学反应具有重要意义。制取“超细”白炭黑研究的结果佐证了ＳＣＩＳＲ强化微观混合的特性。除此以外,ＳＣＩＳＲ在结构方面还具有多项胜过ＳＴＲ的优点,极具开发应用的潜力。     

浸没循环撞击流反应器中的微观混合

Micromixing in the submerged circulative impinging stream reactor (SCISR) developed by the authors is investigated with the Bourne's reaction scheme. The values measured for the impinging velocity, u0, under the conditions of SCISR normal operation, only is of the order of 0.1m·s-1, are much slower than that inferred, suggesting low power requirement for operation. The values of the characteristic time constant for micromixing, tM, determined in the impinging velocity range of 0.184m·s-1 相似文献   

浸没循环撞击流反应器的压力脉动特性

The characteristics of pressure fluctuation in a submerged circulative impinging stream reactor (SCISR) were experimentally studied. The instantaneous signals of pressure fluctuation resulting from the turbulence in the SCISR were measured by sensors and recorded by a computer. The pressure signals at some special positions were sampled at different rotary speeds of propeller. After analyzing the signals with the Power Spectrum method, it was found that there was an inherent frequency in the dynamic pressure signals. The inherent frequencies of the point on the impinging plane were greater than 1000 Hz, so the pressure fluctuation was called high-frequency fluctuation. The fluctuation velocities with high inherent frequency resulted in a strong shear force field, which enabled the fluid to mix quickly on the micro-scale and the agglomerates of solid particles to disperse effectively.     

浸没循环撞击流反应器内的压力波动

Pressure fluctuation in the submerged circulative impinging stream reactor （SCISR） is studied by measuring the dynamic pressure with micro pressure sensors of high accuracy, with water as the process material. Experimental results show that the maximum amplitude of fluctuation can be up to about 1.6kPa. On the power spectra the fluctuation is relatively concentrated in the range of 〈1000Hz, with some weak peeks in acoustic wave range. The space profile of intensive fluctuation region in the reactor is determined. The region is found to take the form of a couple truncated cones of empty core, with coincided bottoms, and is symmetrical with respect to the impinging plane and approximately symmetrical about the axis, essentially independent of u0. The integral intensity of fluctuation increases as the impinging velocity, Uo increasing.     

浸没循环撞击流反应器制备牙膏用磷酸氢钙

采用浸没循环撞击流反应器（SCISR），以焦磷酸钠和磷酸三镁为稳定剂，以磷钙液和石灰乳为原料，通过中和反应法制备出了平均粒度10μm的牙膏用微细磷酸氢钙；探讨了反应温度、熟化时间、反应器装填系数、反应终点pH、磷钙液质量浓度等对产品质量的影响。确定了最优操作条件：磷钙液质量浓度1．17～1．19kg／m^3，反应温度42℃，熟化时间2h，反应终点pH6．3，反应器装填系数0．75。得到产品符合HG3257—2001标准。     

浸没循环撞击流反应器撞击区压力波动的混沌分析

浸没循环撞击流反应器撞击区的压力瞬态信号包含了该区域内流体的许多动态信息,为了分析这些动态信号,采用了一种新的非线性分析方法,即混沌分析.利用小波理论对信号进行过滤,采用重构相空间理论恢复已过滤信号的吸引子.利用数学方法计算刻画混沌吸引子的3个特征参数：关联维、K熵和最大Lyapunov指数.对不同螺旋桨转速及同一y平面上不同测量点位置上算得的特征参数值进行研究,研究结果显示浸没循环撞击流反应器撞击区流体具有混沌特性,而且3个特征参数在不同的螺旋桨转速下及不同的测量点位置具有相同的变化趋势.     

基于PLIF的浸没撞击流反应器的混合特性

利用平面激光诱导荧光技术对水平两喷嘴液-液撞击流反应器内的浓度场进行定性和定量分析,用离析度(IOS)评价时均混合效果,得到不同操作条件下IOS值沿径向射流方向的变化规律,并与三喷嘴的情况进行对比. 结果表明,喷嘴间距L、喷嘴直径D和进口流量Q对反应器混合效果有重要影响,在水平两向撞击流中,当喷嘴直径和流量一定时,随喷嘴间距增大,IOS下降速度加快,最佳间距为L/D=3;当喷嘴间距和流量一定时,随喷嘴直径增大,IOS下降更快,下降到IOS=0.05所需距离不断减小,最佳喷嘴直径D=12 mm;当喷嘴直径和喷嘴间距一定时,随流量增加,IOS下降速度先增加后减小,最佳流量Q=500′10-3 m3/h. 三喷嘴撞击流与两喷嘴变化趋势一致.     

磁场控制下的流-固相反应装置研究进展

一、前言流-固相反应装置在石油、化工、冶金、环保、轻工等部门中已广泛应用。无论是催化反应还是非催化反应装置,相间接触状况对反应的转化率和收率都有重要的影响。流     

浸没对置撞击流的液相混合行为研究

利用无干扰流场测试手段——平面激光诱导荧光技术(PLIF),对浸没对置撞击流混合反应器在等动量撞击下的浓度场进行分析,并分析比较对称撞击和不对称撞击下的液相混合行为。利用混合均匀度U和均匀混合时间τ95定量描述测量平面的示踪剂浓度分布,得出其在不同内径比、不同喷嘴间距下的变化规律,并进一步分析对称撞击时,两喷嘴出口流体的不同动量比对混合的影响。研究发现:在小喷嘴间距L10D(L为喷嘴间距;D为两对置喷嘴内径和的平均值)下,等动量撞击时,对称撞击的混合效果要优于不对称撞击;对称撞击和不对称撞击的最优混合间距均为L=3D。对称撞击时,两喷嘴出口流体的动量比越接近于1,越有利于液相混合。     

Chaotic Analysis of the Concentration Field in a Submerged Impinging Stream Mixer

The concentration field was measured with various nozzle diameters, nozzle distances, and inlet flow rates in a submerged impinging stream mixer (SISM) using planar laser‐induced fluorescence to obtain characteristic parameters such as correlation dimension, Kolmogorov entropy, and Lyapunov exponents that describe the chaos phenomenon and reflect the microcosmic mixture effect of a SISM by mean of the chaos theory. The chaotic characteristic parameters were influenced significantly by different nozzles distances, nozzle diameters, and inlet flow rates and their distributions followed a similar changing regularity by which all parameters decreased with larger nozzle diameter and increased with higher inlet flow rate.     

稠密固液循环流化床内流体湍流脉动对颗粒分散的影响

通过计算流体动力学模拟研究了固液循环流化床内流体湍流对高浓度颗粒的扩散作用。根据湍流机制下高浓度颗粒在液体中的分散机理,建立了同时考虑颗粒碰撞、流体拖拽和流体湍流扩散输运的欧拉-欧拉双流体模型。利用该模型对稠密固液循环流化床提升管内颗粒的分散运动进行了数值模拟,预测出颗粒轴向速度和体积浓度的径向分布,与相应条件下的实验数据符合很好。表明考虑流体湍流扩散输运的理论模型更能精确预测高浓度颗粒在循环流化床提升管内的运动情况;也表明即使针对以颗粒碰撞为主的稠密固液湍流体系,尺度较大的流体湍流涡也会因促使颗粒扩散输运,影响颗粒空间分布。工作为稠密固液循环流化床内两相流体动力学分析奠定了基础。     

碱性离子液体1-乙基-3-甲基咪唑磷酸二乙酯盐在Knoevenagel反应中的应用

考察了碱性离子液体1-乙基-3-甲基咪唑磷酸二乙酯盐{[Em im]+[(EtO)2(PO)O]-}催化一系列醛与活性亚甲基类化合物的Knoevenagel反应,比较了该离子液体在有溶剂存在及无溶剂条件下的催化性能。结果表明,该离子液体在乙醇作溶剂条件下对芳香醛的反应具有较高的催化活性,采用摩尔分数为20%的离子液体来催化该反应,于室温反应即可顺利完成,产率达73.2%~97%,生成相应的取代烯烃化合物。在无溶剂条件下采取机械研磨的方法进行反应,该离子液体表现出更高的催化活性,采用摩尔分数为10%的离子液体进行反应,在1~10 m in即可使产率达90%以上,所得产物均为E式构型。而且在无溶剂条件下,不仅可催化芳香醛的反应,亦可催化脂肪醛的反应。所用离子液体可重复使用,第5次使用时产率仍能达到85.9%。     

CAD 技术在液体发射药组分电位滴定分析中的应用

叙述了在液体发射药组分分析中进行的ＣＡＤ实践,涉及采用瞬态数据记录仪与电位滴定分析仪联机的接口电路设计,以及数据处理编程等计算机数字化测量技术。     

The Influence of Liquid Head and Liquid Circulation on Weeping Rates at a Submerged Orifice

A detailed study of the liquid weeping accompanying bubble formation at a submerged orifice, has shown that the liquid head has a significant effect on weeping rate at low submergence. At increasing values of the liquid head, a critical value will eventually be reached, above which the liquid head has no further influence on weeping rates. In the region where liquid head effects on weeping occur, the presence or absence of stabilizing baffles has a pronounced effect on weeping rates. Experimental evidence suggests that the nature of this influence is related to the magnitude of bulk liquid circulation induced by the upward gas momentum.     

用液下泵充装液氯的工艺特点与分析

介绍了液氯液下泵装置的特点及液下泵充装液氯时的管路安装及工艺流程.该工艺在运行中具有安全性、稳定性等优点,在新乡正华化工有限责任公司应用后,年增效益84.2 万元.