缩放型导流筒气升式内环流生物反应器气相含率研究

研究了传统圆柱型和三种不同结构缩放型导流筒升式人环流生物反应器的气相含率,用排液体积法和压差法分别测定了总气相含率,下降区气相含率及分离区气相含率,并通过质量衡算求得上升区气相含率,实验结果表明,气相含率通气速率提高而增大,三种不同缩放结构参数导流筒的气相含率较接近,且均高于传统圆柱型导流筒气相含率;对于空气－ＣＭＣ溶液系统,随着介质粘度增加,气相含率下降２％～５％,对于三相系统,随着固含率增加,     

Continuous segregation of binary heterogeneous solids in a fast-fluidized bed

Continuous segregation of binary heterogeneous solids (different density mixtures) is carried out in a gas–solid fluidized bed to study the effects of gas velocity, solids feed rate, feed composition and density difference of solids on the separation factor (recovery of flotsam at top outlet) and the quality of the product (purity of flotsam at top outlet) in a continuous fast-fluidized bed. The holdup of the bed material is obtained in each experimental run. It is observed that the separation factor decreases with increase in solids feed rate or density difference of solids, and increases with gas velocity or proportion of flotsam in the feed. The quality of the product decreases with increase in gas velocity or solids flow rate, and increases with feed composition or density difference of solids. The experimental results show that the separation factor and the quality of the product are more sensitive to gas velocity than to other operating parameters. Empirical correlations for predicting the separation factor and quality of the product are proposed based on the Richards model for individual flotsam mass fraction in the feed, and the predictions agree satisfactorily with the present experimental data.     

退化喀斯特地区植被恢复过程中苔藓的先锋作用

在贵州花江喀斯特高原生态综合治理试验示范区内采集苔藓植物样品,鉴别了主要苔藓种类,测定苔藓植物的持水性能,分析了苔藓、岩石接触面形成土壤的化学性质。结果表明：试验区内苔藓植物共有11科26属65种,以藓类植物为主;自然状态下苔藓植物含水率为36 %～898 %;新鲜苔藓持水率为2123 %～5159 %;苔藓、岩石接触面的土壤属于土壤养分分级的一级标准,各项养分指标亦明显高于对照样地。苔藓植物对喀斯特石漠生境有极强的适应性,是石漠化及其他退化生态系统进行人工生态恢复中理想的物种选择。     

水平管段塞流持液率波动规律研究

以空气和水为工质,采用双平行电导探针,在水平多相流环道(d=50.00mm)中研究了段塞流持液率与压力波动的关系以及折算气速、折算液速变化对持液率的影响,并将持液率的试验值与预测模型进行了比较.结果表明:持液率波动能更真实地反映段塞流动特性,可以用来确定液塞频率;增加折算气速时,液塞持液率减小;增加折算液速时,持液率增大.     

搅拌萃取塔液泛速度和滞存率的研究

在内径为90mm的搅拌萃取塔中,对分散相滞存率和液泛速度进行了研究,实验用的物系为煤油－水,煤油－15％甘油水,锭子油－水,2－乙基己醇－水,实验结果表明,转速,相比,物性对液泛速度,滞存率都有影响,而且在较低能耗下搅拌萃取塔处理界面张力大的物系时显示出较大优越性,同时,利用因次分析法,得到了计算滞存率及湍流区液泛速度的关联式。     

内循环三相生物流化床的传质特性研究

探讨了内循环三相生物流化床 (ITFB)的性能特征 ,通过实验研究和理论分析 ,得出计算腐殖酸 (HA)向生物载体传质的传质系数公式     

油-气-水三相流超声传感器持气率测量

为探索油-气-水三相流持气率测量难题,该文开展了脉冲透射式超声传感器持气率测量动态实验研究。首先,利用超声传感器与光纤传感器组合,测取了油-气-水三相流中段塞流、混状流、泡状流的响应信号;其次,提取了超声脉冲信号的最大值序列来反映不同流型时超声传感器响应特性,同时,借助双头光纤传感器与相关测速法,计算得到了流体中气泡弦长序列;最后,结合流型与泡径信息,利用超声传感器测量了不同流型下持气率,并分析了不同流型持气率预测的误差来源,为其他油-气-水三相流持气率测量传感器设计提供了借鉴。     

水平管弹状流液膜区的流动特性研究

将一维形式的双流体模型用于水平管弹状流的液膜区，导出液膜区截面含液率随距离而变的控制方程，讨论了方程的封闭性并提出壁面和界面阻力的计算方法．对液膜区平均截面含液率的计算结果与前人的测量结果作了比较，分析了影响平均截面含液率的因素．通过对截面含液率、液相流速和气相流速沿长度变化的计算分析，首次提出液膜和气弹都是连续波．     

Correlations predicting frictional pressure drop and liquid holdup during horizontal gas-liquid pipe flow with a small liquid holdup

Experimental data and correlations available in the literature for the liquid holdup ε_L and the pressure gradient ΔP_TP/L for gas-liquid pipe flow, generally, do not cover the domain 0 < ε_L < 0.06. Reliable pressure-drop correlations for this holdup range are important for calculating flow rates of natural gas, containing traces of condensate. In the present paper attention is focused on reliable measurements of ε_L and ΔP_TPIL values and on the development of a phenomenological model for the liquid-holdup range 0 < ε_L < 0.06. This model is called the “apparent rough surface” model and is referred to as the ARS model. The experimental results presented in this paper refer to air-water and air-water + ethyleneglycol systems with varying transport properties in horizontal straight smooth glass tubes under steady-state conditions. The holdup and pressure gradient values predicted with the ARS model agree satisfactorily with both our experimental results and data obtained from the literature referring to small liquid-holdup values 0 < ε_L < 0.06. Further, it has been shown that in the domain 38 < < 72 mPa m the interfacial tension of the gas-liquid system has no significant effect on the liquid holdup. The pressure gradient, however, increases slightly with decreasing surface tension values.     

液体粘度对三相流化床局部相含率径向分布的影响

应用开发的微电导探针测试技术,以粒径分别为0．48mm、0．80mm、12．5mm的玻璃珠和1．45mm的苯乙烯树脂为固相,空气为气相,水和0．05％（wt％）、0．20％（wt％）的羧甲基纤维素钠（SCMC）为液相,对三相流化床的各相局部相含率进行了同时测定。在不同液体粘度下,局部固含率在r／R=0．75-0．85范围内有一个极大值;局部气合率呈现出塔中心处最大,塔壁处最小的分布规律。表明液体粘度对局部相含率径向分布均有不同程度的影响。