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Development of a pentaethylenehexamine-modified solid support adsorbent for CO_2 capture from model flue gas

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Chinese Journal of Chemical Engineering 2015年第2期23卷 366-371页

作者：韦力靖宇高正明王运东 School of Chemical Engineering Beijing University of Chemical Technology The State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University

A novel solid support adsorbent for CO2capture was developed by loading pentaethylenehexamine(PEHA)on commercially available mesoporous molecular sieve MCM-41 using wet impregnation ***-41 samples before and after PEHA loading were characterized by X-ray powder diffraction,N2adsorption/desorption,thermal gravimetric analysis and scanning electron microscope to investigate the textural and thermo-physical ***2adsorption performance was evaluated in a fixed bed adsorption *** indicated that the structure of MCM-41 was preserved after loading *** area and total pore volume of PEHA loaded MCM-41 decreased with the increase of *** working adsorption capacity of CO2could be significantly improved at 60%of PEHA loading and 75°*** effect of the height of adsorbent bed was investigated and the best working adsorption capacity for MCM-41-PEHA-60 reached 165 mg·(g adsorbent)-1at 75°***/desorption circle showed that the CO2working adsorption capacity of MCM-41-PEHA kept stable.

关键词： CO2adsorption Pentaethylenehexamine MCM-41 molecular sieve CO2adsorbent

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多层组合桨搅拌槽内气-液分散特性的研究

高校化学工程学报 2004年第5期18卷 547-552页

作者：郝志刚包雨云高正明北京化工大学化学工程学院北京100029

在直径为0.476m的椭圆底搅拌槽中,采用由六叶半椭圆管叶盘式涡轮桨(HEDT)及四叶宽叶翼型桨的上提(WHU)及下压(WHD)操作组合的六种不同的三层桨,研究了气-液两相体系中的通气功率变化及气含率特性,获得不同桨型的通气搅拌功率及气含率的... 详细信息

在直径为0.476m的椭圆底搅拌槽中,采用由六叶半椭圆管叶盘式涡轮桨(HEDT)及四叶宽叶翼型桨的上提(WHU)及下压(WHD)操作组合的六种不同的三层桨,研究了气-液两相体系中的通气功率变化及气含率特性,获得不同桨型的通气搅拌功率及气含率的关联式;结果表明,底桨为HEDT的组合桨通气功率下降幅度最小,相同输入功率时气含率最高,其次为WHD,WHU为底桨时气液分散性能最差。因此,适用于气液两相操作的优化组合桨应以HEDT为底桨。此研究结果可为工业用多层组合桨气液搅拌反应器的设计提供参考。

关键词：通气功率气含率气-液分散组合桨搅拌槽

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核爆炸装置热力学研究

原子能科学技术 2010年第3期44卷 331-338页

作者：高正明何彬赵娟第二炮兵工程学院陕西西安710025 荆楚理工学院电子信息工程学院湖北荆门448000

为研究放热材料释放的热能对核爆炸装置力学性能的影响,采用公开资料,对核爆炸装置进行热力学分析。通过级联衰变动力学计算得到每千克武器级钚、武器级铀及贫化铀的放热功率,并对仿真结果进行拟合分析;选取其最大值对Steve Fetter提出... 详细信息

为研究放热材料释放的热能对核爆炸装置力学性能的影响,采用公开资料,对核爆炸装置进行热力学分析。通过级联衰变动力学计算得到每千克武器级钚、武器级铀及贫化铀的放热功率,并对仿真结果进行拟合分析;选取其最大值对Steve Fetter提出的公开核装置假想模型进行温度场数值仿真;根据工业生产实际对Steve Fetter提出的公开核爆炸装置假想模型进行修订,并对其进行热应力仿真分析。结果表明:Steve Fetter提出的4种核爆炸装置的热力学性能极差,不能在现实中存在。

关键词：核爆炸装置放热功率温度场数值仿真热力学分析

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涡轮桨搅拌槽内流动特性的大涡模拟

高校化学工程学报 2007年第4期21卷 592-597页

作者：李志鹏高正明北京化工大学化学工程学院北京100029

利用大涡模拟方法研究了涡轮桨搅拌槽内的流动特性,采用了三种亚格子模式:标准Smagorinsky-Lilly模式(SLM)、Smagorinsky-Lilly动力模式(DSLM)和亚格子动能动力模式(DKEM),并将模拟结果与标准k-ε模型及文献实验数据进行了详细的比较。... 详细信息

利用大涡模拟方法研究了涡轮桨搅拌槽内的流动特性,采用了三种亚格子模式:标准Smagorinsky-Lilly模式(SLM)、Smagorinsky-Lilly动力模式(DSLM)和亚格子动能动力模式(DKEM),并将模拟结果与标准k-ε模型及文献实验数据进行了详细的比较。结果表明:大涡模拟方法可获得搅拌槽内的瞬态流场;对桨叶区时均速度及湍流动能的预测与实验数据相吻合,比标准k-ε模型计算结果有明显改进,三种亚格子模型中DSLM和DKEM模拟结果更好。同时分析了大涡模拟中桨叶端部附近湍流动能估计偏差的原因,发现主要是由于对轴向湍流均方根速度的预测偏差造成的。大涡模拟方法为搅拌槽内非稳态、周期性的湍流流动和湍流特性的研究提供了强有力的工具。

关键词：计算流体力学(CFD) 大涡模拟(LES) 流动特性搅拌槽涡轮桨

Micromixing efficiency in a T-shaped confined impinging jet reactor

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Chinese Journal of Chemical Engineering 2015年第2期23卷 350-355页

作者：高正明韩敬包雨云李志鹏 State Key Laboratory of Chemical Resource Engineering School of Chemical Engineering Beijing University of Chemical Technology

Confined impinging jet reactor(CIJR)offers advantages for chemical rapid processes and has become an important new reactor used in the chemical *** micromixing efficiency in a T-shaped CIJR for two tubes of inner diameter of 3 mm was studied by using a parallel competing iodide–iodate reaction as the working *** this work,the effects of different operating conditions,such as impinging velocity and acid concentration,on segregation index were *** addition,the effects of the inner nozzles diameter and the distance L between the jet axis and the top wall of the mixing chamber on the micromixing efficiency were also *** is concluded that the best range of L in this CIJR is 6.5–12.5 *** on the incorporation model,the estimated minimum micromixing time tmof CIJR approximately equals to 2×*** experimental results indicate clearly that CIJR possesses a much better micromixing performance compared with the conventional stirred tank(micromixing time of 2×10-3to 2×10-2s).Hence,it can be envisioned that CIJR has more promising applications in various industrial processes.

关键词： Impinging jet reactor Micromixing Segregation index Incorporation model

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支撑体对γ辐射物探测数据的影响

核技术 2016年第2期39卷 33-38页

作者：赵娟高正明荆楚理工学院电子信息工程学院荆门448000 宝鸡高新技术研究所宝鸡721013

在对大质量高安全性要求的γ源进行辐射探测时,发现数据误差很大,不能用于定量分析。为此,基于探测器端面注量率参数理论探析了地面或支撑台对探测器数据影响的简化计算方法,采用蒙特卡罗方法分析了混凝土支撑体对粒子注量率的影响程度... 详细信息

在对大质量高安全性要求的γ源进行辐射探测时,发现数据误差很大,不能用于定量分析。为此,基于探测器端面注量率参数理论探析了地面或支撑台对探测器数据影响的简化计算方法,采用蒙特卡罗方法分析了混凝土支撑体对粒子注量率的影响程度,研究了铅作为次级粒子吸收物质时,铅厚度和半径与注量率测量误差之间的关系。研究结果表明,在放射性材料辐射探测过程中,为减少混凝土支撑体对辐射探测数据的影响,应采用厚度不小于0.5 cm、半径不小于源高3倍的铅板作为次级粒子吸收体,可将探测数据最大误差由22%减少至15%左右,最小可接近10%,实验结果证实了该方法的有效性。

关键词：支撑体放射性材料 γ辐射探测蒙特卡罗方法

Void Fraction Distributions in Cold-gassed and Hot-sparged Three Phase Stirred Tanks with Multi-impeller

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Chinese Journal of Chemical Engineering 2009年第6期17卷 887-895页

作者：陈雷包雨云高正明 School of Chemical Engineering Beijing University of Chemical Technology Beijing 100029 China

Vertical distributions of void fraction in gas-liquid and gas-liquid-solid stirred tanks have been measured in a fully baffled dished base vessel of 0.48 m diameter, using a conductivity probe. The impeller configuration （a hollow half elliptical blade dispersing turbine below two up-pumping wide blade hydrofoils, identified as HEDT＋2WHu） recommended in previous work has been used in this work. The operating temperatures were 24℃ and 81℃, identified as cold and hot respectively. The effects of superficial gas velocity, agitator speed and the corresponding power input on the local void fraction in two-phase systems are .investigated and discussed. Results show thatth-e increasing of agitator speed or gas flow rate leads to an increase in local-void fraction at the majority of measurement points in both cold and hot systems. However, the unifo,rmity of gas dispersion does not always in crease as the raising of agitator speed and power input. In either cold or hot sparged conditions, the two- and three-phase *** similar vertical profiles for void fraction, with maxima in similar locations; however, the void fractions are significantly lower in hot sparging than with cold. In cold operation the presence of particles leads to a lower void fraction at most points, although the local void fractions increase a little with the addition of solid particles at high temperature, in good agreement with the global gas holdup results, and the possible reasons are discussed in this paper. This work can give a better understanding of the differences between cold-gassed and hot-sparged three phase＇stirred tanks.

关键词： void fraction conductivity probe hot sparged reactor dispersed gas distribution multi-impeller

Influence of impeller diameter on local gas dispersion properties in a sparged multi-impeller stirred tank

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Chinese Journal of Chemical Engineering 2015年第4期23卷 615-622页

作者：包雨云杨杰王冰洁高正明 State Key Laboratory of Chemical Resource Engineering School of Chemical Engineering Beijing University of Chemical Technology

Vertical distributions of local void fraction and bubble size in air-water dispersion system were measured with a dual conductivity probe in a fully baffled dished base stirred vessel with the diameter T of 0.48 m, holding 0.134 m3 liquid. The impeller combination with a six parabolic blade disk turbine below two down-pumping hy- drofoil propellers, identified as PDT ＋ 2CBY, was used in this study. The effects of the impeller diameter D, rang- ing from 0.30T to 0.40T （corresponding to D/T from 0.30 to 0.40）, on the local void fraction and bubble size were investigated by both experimental and CFD simulation methods. At low superficial gas velocity Vs of 0.0077 m· s-1, there is no obvious difference in the local void fraction distribution for all systems with different D/T. However, at high superficial gas velocity, the system with a D/TofO.30 leads to higher local void fraction than systems with other D/T. There is no significant variation in the axial distribution of the Sauter mean bubble size for all the systems with different D/T at the same gas superficial velocity. CFD simulation based on the two-fluid model along with the population balance model （PBM） was used to investigate the effect of the impeller diameter on the gas-liquid flows. The local void fraction predicted by the numerical simulation approach was in reasonable a^reement with the experimental data.

关键词： Impeller diameterLocal void fractionBubble sizeCFD-PBMMixing

Effects of the Blade Shape on the Trailing Vortices in Liquid Flow Generated by Disc Turbines

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Chinese Journal of Chemical Engineering 2011年第2期19卷 232-242页

作者：赵静高正明包雨云 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Particle image velocimetry technique was used to analyze the trailing vortices and elucidate their rela-tionship with turbulence properties in a stirred tank of 0.48 m diameter,agitated by four different disc turbines,in-cluding Rushton turbine,concaved blade disk turbine,half elliptical blade disk turbine,and parabolic blade disk ***-averaged and phase-resolved flow fields near the impeller blades were measured and the structure of trailing vortices was studied in *** location,size and strength of vortices were determined by the simplified λ2-criterion and the results showed that the blade shape had great effect on the trailing vortex *** larger curvature resulted in longer residence time of the vortex at the impeller tip,bigger distance between the upper and lower vortices and longer vortex life,also leads to smaller and stronger *** addition,the turbulent ki-netic energy and turbulent energy dissipation in the discharge flow were determined and *** turbulent kinetic energy and turbulent energy dissipation regions were located between the upper and lower vortices and moved along with *** restricted to single phase flow,the presented results are essential for reliable de-sign and scale-up of stirred tank with disc turbines.

关键词： trailing vortices disc turbine particle image velocimetry blade shape