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61.
A. D. Raidoo K.S.M.S. Raghav Rao S. B. Sawant J. B. Joshi 《Chemical Engineering Communications》1987,54(1):241-264
Rate of gas induction, static pressure, mixing time and power consumption have been measured in 0.57 m i.d. vessel. Different types of impellers namely shrouded disc turbine, shrouded curved blade turbine and pitched blade turbine were used. The impeller diameter was varied from 0.15-0.25 m and the impeller speed was varied from 3 to 20 r/s.
The pitched blade turbine was found to give 30-60 per cent higher rates of gas induction as compared with the best design reported in the literature. The mixing time was found to be lower by a similar magnitude. Moreover in the case of pitched blade turbine it was found that the gas was getting induced radially as well as axially. This eliminates the necessity of the diffuser and hence reducing the complexities in the mechanical structure. 相似文献
The pitched blade turbine was found to give 30-60 per cent higher rates of gas induction as compared with the best design reported in the literature. The mixing time was found to be lower by a similar magnitude. Moreover in the case of pitched blade turbine it was found that the gas was getting induced radially as well as axially. This eliminates the necessity of the diffuser and hence reducing the complexities in the mechanical structure. 相似文献
62.
根据实测γ~∞_1用单参数Wilson方程预测均三甲苯-DMP和偏三甲苯-DMP二元体系汽液平衡,并推算均三甲苯-偏三甲苯-DMP三元体系的汽液平衡,与实测数据比较,均获得良好结果。 相似文献
63.
Johannes C. Jansen Marialuigia Macchione Raniero Mendichi Enrico Drioli 《Polymer》2005,46(25):11366-11379
Asymmetric gas separation membranes were prepared by the dry-casting technique from PEEKWC, a modified amorphous glassy poly(ether ether ketone). The phase inversion process and membrane performance were correlated to the properties of the polymer and the casting solution (molar mass, polymer concentration, solution rheology and thermodynamics). It was found that a broad molar mass distribution of the polymer in the casting solution is most favourable for the formation of a highly selective membrane with a dense skin and a porous sub-layer. Thus, membranes with an effective skin thickness of less than 1 μm were obtained, exhibiting a maximum O2/N2 selectivity of 7.2 and a CO2/CH4 selectivity of 39, both significantly higher than in a corresponding thick dense PEEKWC membrane and also comparable to or higher than that of the most commonly used polymers for gas separation membranes. The CO2 and O2 permeance were up to 9.5×10−3 and 1.8×10−3 m3/(m2 h bar) (3.5 and 0.67 GPU), respectively. 相似文献
64.
Tracer tests were conducted at the 6,000 pounds of ozone per day Tucson, CAP Water Treatment Plant in Tucson, Arizona. The tests were designed to determine T10 values through the contactors at various operating conditions. The tests were modeled using three techniques. Peclet Number was calculated for each of the runs, which would indicate the hydrodynamic conditions inside the ozone contactor. The results indicated that the increase in water flow rate and the number of cells with gas flow increased Peclet Number. The flow rate of liquid seemed to impact the Peclet Number more than gas flow. The headloss in each cell appeared to be important in controlling the distribution of liquid and gas through the cell. A correlation was developed between the product of gas and liquid phase Reynolds Number and Peclet Number. 相似文献
65.
从设计角度对燕化200kt/a气相法聚丙烯装置的技术改造进行了详细分析和说明。装置改造获得了最大的经济效益,为国内同类装置进行技术改造提供了经验。 相似文献
66.
67.
Li-doped NiO was synthesized by molten salt method. LiNO3-LiOH flux was used as a source for Li doping. NiCl2 was added to the molten Li flux and then processed to make the Li-doped NiO material. Li:Ni ratios were maintained from 5:
1 to 30: 1 during the synthetic procedure and the chemical compositions after characterization were found from Li0.08Ni0.92O to Li0.16Ni0.84O. Li doping did not change the basic cubic structural characteristics of NiO as evidenced by XRD studies; however, the lattice
parameter decreased from 0.41769 nm in pure NiO to 0.41271 nm in Li0.16Ni0.84O. Hydrogen gas sensors were fabricated by using these materials as thick films on alumina substrates. The half surface of
each sensor was coated with the Pt catalyst. The sensor, when exposed to the hydrogen gas blended in air, heated up the catalytic
surface leaving the rest half surface (without catalyst) cold. The thermoelectric voltage thus built up along the hot and
cold surface of the Li-doped NiO made the basis for detecting hydrogen gas. The linearity of the voltage signal vs H2 concentration was checked up to 4% of H2 in air (as higher concentrations above 4.65% are explosive in air) using Li0.10Ni0.90O as the sensor material. The response time T90 and the recovery time RT90 were less than 25 sec. H2 concentration from 0.5% to 4% showed a good linearity against voltage. There was minimum interference of other gases and
hence H2 gas can easily be detected. 相似文献
68.
底吹钢包两相区两段模型 总被引:1,自引:0,他引:1
在考虑雷诺应力的基础上,建立了底吹钢包中气液两相区流体流动的两段模型。这一模型可用于计算近喷嘴处和浮羽流区各截面处两相流的平均速度、速度分布、流股直径和平均含气率等.数值计算表明:理论含气率与实验值符合很好.计算还表明:平均含气率和平均速度随高度的增大而减小,但流股直径随高度的增大而增大.另一方面,平均速度随初始供气量的增大而增大,而抽引比则随供气量增大而减小.通过两段模型可很好地描述喷嘴处气液流的行为. 相似文献
69.
测定了60℃和2-600bar时由CO2和He、Ar、SF6以及CHF3组成的等分子二元混合物的压缩因子,根据纯物质和混合物的压缩因子计算了压力混合效应和过剩体积。对于真实气体混合性质的描述,本文采用五参数的BACK方程,方程计算值与实验值符合较好。 相似文献
70.
本文在热态条件下,研究了鼓泡浆液反应器的气含率、反应器直径为0.098m,物系组成为氮气-液体石腊-石英砂。考察了气速、压力、温度、静床高及固体引入等因素对气含率的影响。对于53μm粒子的三相浆态体系,气含率与表观气速关系式为εG=0.053uG^1.2。 相似文献