Numerical Simulation and Experimental Study on the Performance of Gas/liquid Spiral Separator

The gas/liquid spiral separator, a key component in the compressed air system, was used to remove liquid and oil from gas stream by centrifugal and gravitational forces. To optimize the design of the separator,the relationship between the performance and structural parameters of separators is studied. Computational fluid dynamics (CFD) method is employed to simulate the flow fields and calculate the pressure drop and separation efficiency of air-liquid spiral separators with different structural parameters. The RSM (Reynolds stress model)turbulence model is used to analyze the highly swirling flow fields while the stochastic trajectory model is used to simulate the traces of liquid droplets in the flow field. A simplified calculation formula of pressure drop in spiral structures is obtained by modifying Darcy's equation and verified by experiment.

Performance of Inner-core Supersonic Gas Separation Device with Droplet Enlargement Method

To improve the separation performance of a supersonic gas separation device for the treatment of gas mixture with a single heavy component, a novel structure with shorter settlement distance was constructed and a method of droplet enlargement was applied. A series of experiments were carried out in the improved separation device under various conditions, using air-ethanol vapor as the medium and micro water droplets as nucleation cen- ters. The effects of the inlet pressure, temperature and relative humidity, the swirling intensity, and mass flow rate of water on the separation performance were investigated. The separation was improved by increasing the inlet pressure and relative humidity. With the decrease of swirling intensity and mass flow rate of water, the separation efficiency increased first and then decreased. The inlet temperature had a slight effect on the separation. The results showed that the separation performance was effectively improved using the proposed structure and method, and the best separation in this study was obtained with the ethanol removal rate about 55% and dew point depression 27 K. The addition of water had little pollution to the air-ethanol vapor system since the water carry-over rate was within the range of -2 %-0 in most cases.

The combination of 1-octyl-3-methylimidazolium tetrafluorborate with TBAB or THF on CO2 hydrate formation and CH4 separation from biogas

[C_8min] BF_4 was used in this work to combine with TBAB or THF for the investigation about thermodynamic and kinetic additives on CO_2 and CH_4/CO_2 hydrates. The results show that [C_8min] BF_4 has the inhibition effect on the equilibrium of hydrate formation. About the kinetic study, [C_8 min] BF_4 could improve the rate of CO_2 hydrate formation and increase the gas uptake in hydrate phase. At the same time, the combination of TBAB and [C8 min] BF_4 could increase the mole friction of CH_4 in residual gas comparing with the data in THF solution. CH_4 separation efficiency was strongly enhanced. Since that the size of CO_2 and CH_4 molecules are similar, CH_4 and CO_2 could form the similar hydrate, so the recovery of CH_4 from biogas decreases lightly. The CH_4 content in biogas can purified from 67 mol% to 77 mol% after one-stage hydrate formation. In addition, the combination of THF and[C_8 min] BF_4 do not have obvious promoting effect on CH_4 separation comparing with the gas separation results in pure THF solution.

Assembling ionic liquid into porous molecular filler of mixed matrix membrane to trigger high gas permeability,selectivity,and stability for CO_(2)/CH_(4) separation

As an emerging zero-dimensional nano crystalline porous material,porous organic cages(POCs)with soluble properties in organic solvents,are promising candidates as molecular fillers in mixed matrix membranes(MMMs).The pore structure of POCs should be adjusted to trigger efficient gas separation performance,and the interaction between filler and matrix should be optimized.In this work,ionic liquid(IL)was introduced into the molecular fillers of CC3,to construct the IL@CC3/PIM-1 membrane to effectively separate CO_(2) from CH_(4).The advantages of doping IL include:(1)narrowing the cavity size of POCs from 4.4 to 3.9Åto enhance the diffusion selectivity,(2)strengthening the CO_(2) solubility to heighten the gas permeability,and(3)improving the compatibility between filler and matrix to upgrade membrane stability.After the optimization of the membrane composite,the IL@CC3/PIM-1-10%membrane possesses the CO_(2) permeability of 7868 Barrer and the CO_(2)/CH_(4) selectivity of 73.4,which compared to the CC3/PIM-1-10%membrane,improved by 15.9%and 106.2%,respectively.Furthermore,the membrane has maintained a stable separation performance at varied temperatures and pressures during the long-term test.The proposed method offers an efficient way to improve the performance of POCs-based MMMs in gas separation.

Permeability and Selectivity of Sulfur Dioxide and Carbon Dioxide in Supported Ionic Liquid Membranes

Permeabilities and selectivities of gases such as carbon dioxide （CO2）, sulfur dioxide （SO2）, nitrogen （N2） and methane （CH4） in six imidazolium-based ionic liquids （[emim][BF4], [bmim][BF4], [bmim][PF6], [banim][BF4], [bmim][Tf2N] and [emim][CF3SO3]） supported on polyethersulfone microfiltration membranes are investigated in a single gas feed system using nitrogen as the environment and reference component at temperature from 25 to 45℃ and pressure of N2 from 100 to 400 kPa. It is found that SO2 has the highest permeability in the tested supported ionic liquid membranes, being an order of magnitude higher than that of CO2, and about 2 to 3 orders of magnitude larger than those of N2 and CH4. The observed selectivity of SO2 over the two ordinary gas components is also striking. It is shown experimentally that the dissolution and transport of gas components in the supported ionic liquid membranes, as well as the nature of ionic liquids play important roles in the gas permeation. A nonlinear increase of permeation rate with temperature and operation pressure is also observed for all sample gases. By considering the factors that influence the permeabilities and selectivities of CO2 and SO2, it is expected to develop an optimal supported ionic liquid membrane technology for the isolation of acidic gases in the near future.

Performance of Dual-throat Supersonic Separation Device with Porous Wall Structure

In this paper, a dual-throat supersonic separation device with porous wall has been proposed to solve the starting problem of supersonic separator, and the feasibility of the proposed device has been tested numerically and experimentally. Its flow characteristics have been investigated and the effect of some important parameters includ-ing nozzle pressure ratio(RNP), inlet temperature and swirl intensity were examined. In the device, the supersonic flow state and strong centrifugal acceleration of 240000g can be obtained, which are necessary for the condensation and separation of water vapor. The supersonic region in the device enlarged and the shock wave shifted downstream along with the increasing RNP. The separation performance was improved with the increasing RNP and the inlet temperature. The best separation performance in this study was obtained with ΔTd? 28 K.

静态水气分离器分离效率试验研究

目的评估某型静态水气分离器的分离效率。方法采用自行设计搭建的重力条件下地面试验系统,对水气分离器分离效率的评价方法进行了研究,针对激光颗粒测试仪监测法精度不足的问题,提出了重量测试法。采用重量测试法考查了水滴直径、重力以及工作时间等因素对水气分离器分离效率的影响。结果在气体流量为150 L/min,水流量为120~200 g/h的设计条件下,静态测试分离效率平均为（73±11）%,水气分离器气体出口向下动态测试分离效率平均为（87±5）%。同时设计工况下水滴直径和重力对分离效率无影响。结论静态水气分离器分离性能满足设计要求,地面重力条件下水气分离器性能模拟试验方法合理,是水气分离器分离效率研究的有效评价手段。

静态水气分离器分离效率数值模拟

目的评估某型静态水气分离器的分离效率。方法采用计算流体力学欧拉-拉格朗日方法对静态水气分离器进行了数值模拟,建立水滴均匀和非均匀粒径的分离效率统计模型,考查水滴直径、气流速度分布、重力等多个因素对分离效率的影响。结果分离效率的计算值与试验值平均误差小于15%;给定入口气流速度分布,分离效率随着粒径的增大而提高;给定径向和切向速度,分离效率随轴向速度变化显著;考虑重力影响时的分离效率较高,粒径越大影响越明显。结论数值模型和方法合理,为该静态水气分离器性能改进提供了参考依据,并为其它形式的水气分离器性能分析提供了有效的数值方法。

微重力环境电解水制氢气液分离方法研究进展

电解水制氢是目前常用的制取氢气方法,而气液分离技术是整个电解水制氢系统的核心技术之一,用以除去氢气中混有的液态水。气液分离技术按照分离机理可分为重力沉降分离、惯性碰撞分离、旋流分离等方式。为适应航天工程发展,我国正在开展月球制氢的研究。分别在地面环境和月球微重力环境下,对重力分离器和旋流分离器的分离效果进行对比仿真分析。仿真结果表明,在月球微重力环境下,受重力场减弱的影响,重力分离器分离效果变差,不宜使用。微重力环境下常用的气液分离技术按是否含有运动部件分为静态分离和动态分离。吸附分离利用多孔材料吸收实现分离,成本低、操作简单,但效率偏低;毛细作用分离利用表面张力实现分离,分离效果好,但存在管道设计问题;旋流分离和动态离心分离都是利用气液两相的密度差异实现分离,体积小、可靠高效,但前者需要预先设计复杂管路,后者需要额外供给电机能量并关注密封、振动问题;惯性分离通常只作为辅助手段。溶解分离通过改变溶解度使气体暂时溶解于液体中,从而有效避免气体杂质对于整个系统的危害,目前尚处于研究阶段。

Facilitated transport separation of CO_(2) and H_(2)S by supported liquid membrane based on task-specific protic ionic liquids

Selective separation of CO_(2) and H_(2)S from CH_(4) is of importance to the natural gas upgrading because of its cor-rosivity. As is well known, amine group can recognize reversibly CO_(2) and H_(2)S with a moderate interaction. Withthis in mind, this work prepared a series of amine-functionalized supported-protic-ionic-liquid membranes(SPILMs) for the selective separation of CO_(2) and H_(2)S from CH_(4) . For comparison, aprotic ionic liquid membranewas also prepared for natural gas sweetening. The effect of temperature and transmembrane pressure differenceon the permeability of single gas and ideal selectivity of CO_(2)/CH_(4) and H_(2)S/CO_(2) were studied. Facilitated transportmechanism was studied by NMR spectra. The permeability of CO_(2) in primary amine functionalized [DMPDAH][Tf_(2)N]-based membrane decreases with the increasing transmembrane pressure, indicating a typical feature offacilitated transport membrane. The permeability of CO_(2) and the ideal selective of CO_(2)/CH_(4) are as high as 2000 barrers and 53.2 at 313.2 K in [DMPDAH][Tf_(2)N] membrane, significantly higher than those in conventional ILsmembrane. It is anticipated that these amine-functionalized SPILMs can provide alternative insight for the se-lective separation of CO_(2) and H_(2)S from CH_(4) .

Pore engineering of ZIF-8 with ionic liquids for membrane-based CO_(2)separation:bearing functional group effect

CO_(2)separation performance of polymer membranes can be significantly enhanced by selecting porous fillers with high CO_(2)affinity.Ionic liquids incorporation has been recognized as an effective strategy for improving the separation ability of pristine porous fillers.However,the influence of the specific functional groups of ILs in IL@MOF composites on separation performance of MMMs still remains unclear.Herein,we designed three microenvironment-tuned IL@ZIF-8 composites in which the three ILs contain different functional groups(-CH3,–SO3H,and–NH2).Molecular simulation results showed that the NH2-IL@ZIF-8 has a commendable CO_(2)adsorption capacity and CO_(2)/CH4 adsorptive selectivity,and the results were well confirmed by the following experimental data.More importantly,the prepared NH2-IL@ZIF-8 based MMMs also exhibit superior CO_(2)separation performance among the three IL@ZIF-8 based MMMs owning to its high CO_(2)affinity.Thus,this work can provide guidance for designing IL@MOF composites for MMMs fabrication towards gas separation,and the research mode combining molecular simulation prediction and experimental verification can afford valuable reference for material development in membrane separation field.

热电装置达标提效开发与改造

针对巴陵石化热电装置制粉系统电耗偏高、排污率偏高、疏水泄漏较大、锅炉效率偏低、过热器爆管等诸多问题,开发了制粉系统自适应模糊控制系统和静动叶结合型旋转式粗粉分离器、锅炉连续排污测控系统,采用T91材料对高温过热器材质升级、炉顶及水冷壁密封改造、疏水系统闭式回收改造等措施,有效地控制了煤粉的均匀度,降低了制粉电耗,减少了炉水排放,锅炉热效率提高1.62%。

Synthesis of porous aromatic framework with Friedel–Crafts alkylation reaction for CO_2 separation

A novel porous aromatic framework, PAF-8, derived from tetraphenylsilane as basic building unit, was successfully synthesized via Friedel-Crafts alkylation reaction. This PAF material had high thermal stability as well as high surface area （785 m^2 g^-1） calculated from the Brunauer-Emmett-Teller （BET） model. Meanwhile, PAF-8 possessed high performances in gas sorption and especially for CO2 separation.

Gain deeper insights into traditional Chinese medicines using multidimensional chromatography combined with chemometric approaches

Traditional Chinese medicines(TCMs)possess a rich historical background,unique theoretical framework,remarkable therapeutic efficacy,and abundant resources.However,the modernization and internationalization of TCMs have faced significant obstacles due to their diverse ingredients and unknown mechanisms.To gain deeper insights into the phytochemicals and ensure the quality control of TCMs,there is an urgent need to enhance analytical techniques.Currently,two-dimensional(2D)chromatography,which incorporates two independent separation mechanisms,demonstrates superior separation capabilities compared to the traditional one-dimensional(1D)separation system when analyzing TCMs samples.Over the past decade,new techniques have been continuously developed to gain actionable insights from complex samples.This review presents the recent advancements in the application of multidimensional chromatography for the quality evaluation of TCMs,encompassing 2D-gas chromatography(GC),2D-liquid chromatography(LC),as well as emerging three-dimensional(3D)-GC,3D-LC,and their associated data-processing approaches.These studies highlight the promising potential of multidimensional chromatographic separation for future phytochemical analysis.Nevertheless,the increased separation capability has resulted in higher-order data sets and greater demands for data-processing tools.Considering that multidimensional chromatography is still a relatively nascent research field,further hardware enhancements and the implementation of chemometric methods are necessary to foster its robust development.

Ionothermal synthesis of AlPO-34 membranes on macroporous α-Al_(2)O_(3) supports without using organic template

Continuous and compact AlPO-34 molecular sieve membranes were successfully synthesized on the outer surface of macroprous tubeα-Al_(2)O_(3)supports under secondary ionothermal growth with the proposed wetting seed layer.The recyclable ionic liquids(ILs)can both act as solvent media and the structure-directing agent(SDA)of the aiming topological structure of CHA,largely reducing the wastewater.Wetting the seed layer could accelerate the diffusion of ILs to the surface of the support and further increase the binding force between the membrane and the support.Compared with the open system,the closed system led to the achievement of the high-quality AlPO-34 membrane.The H_(2)permeance of the resulting membrane was 9.74×10^(-8)mol m^(-2)s^(-1)Pa^(-1)and the ideal selectivities of H_(2)/CO_(2),H_(2)/N_(2),H_(2)/CH_(4),H_(2)/C3H8 and H_(2)/i-C4H10 were 7.48,8.54,14.67,39.25 and 65.83,respectively,which were higher than Knudsen diffusion ratios.The obtained membrane was firstly explored for the PV dehydration of isopropyl alcohol(90 wt%)/water mixtures,exhibiting good performance with the separation factor of 147 and high water flux of 1.09 kg m^(-2)h^(-1).