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A new type of feeding system by an extruder-feeder was utilized to pump high concentrations of slurries into an advanced biomass liquefaction reactor operating at pressures of up to 25 MPa and temperatures of up to 400°C. The operability of such an extruder-feeder and the design criteria for this type of unit operation are described, and operational data are reported. Three types of extruder-feeders were used, and many different types of feedstocks were tested. The extruder-feeder proved to be effective in the biomass direct liquefaction process and could prove applicable in many other processes where high concentrations of solids are to be pumped, thus reducing drastically the size of the plant and the need for recycle of large amounts of liquid carriers for the solids. Typical experimental data and results of the flow rates and pressure generation for the various extruder-feeders and their operational conditions for several feedstocks are reported. The theoretical models developed for plasticating extruders were found to be acceptable also for the extruder-feeder of biomass feedstock, applying appropriate drag and pressure flow coefficients. 相似文献
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液膜中空化的发生直接影响着密封流体动压润滑性能,基于质量守恒的JFO边界条件,建立考虑表面粗糙度的螺旋槽液膜密封物理模型,经坐标变换将不规则物理域转换成规则计算域,采用有限控制体积法离散控制方程并求解,分析了膜厚、表面粗糙度、螺旋槽功用(上游泵送和下游泵送)、螺旋槽开槽位置及空化压力对液膜中空化发生的影响。结果表明:较小膜厚工况易促生空穴,而较大膜厚易削弱空穴,且随着膜厚增大,表面粗糙度的影响降低甚至被忽略;当密封为上游泵送型时,空穴区周向宽度明显大于下游泵送型,而螺旋槽位置对空化的影响与螺旋槽功用密切相关;选取较小空化压力使空穴缩减,而较大者反之,且后者对提升液膜承载有利。 相似文献
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通过激光多谱勒测速仪对搅拌槽内三维流场的测量,定义了具有三维意义上的总体泵送能力系数,并提出了由切向速度定义的泵送能力系数的概念,这些量较初始泵送能力系数和循环流量更能真正反映搅拌槽内的流动和混合。 相似文献
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以内径为24mm的垂直管道浸取器的一根上行管为升液管,用水和55 ̄65目河砂配成各种浓度的悬浮液做冷模试验。在水的表面流速为0.15 ̄0.65m/s空气表观流速为0.05 ̄2.15m/s,固相质量分率为0 ̄15%,以及充气高度为2.280 ̄3.379m的实验范围内,观察了空气升液器的运行情况,测定了扬程、效率,还比较了进气孔径的影响。本文结合垂直管道浸取器的特点,引入气相滞留率和摩擦压力降模型,并 相似文献
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Shiva Moradi Mehr Mohammad A. Charsooghi Luca Businaro Mehdi Habibi Ali-Reza Moradi 《American Institute of Chemical Engineers》2023,69(3):e17847
The famous two-balloon experiment involves two identical balloons filled up with air and connected via a hollow tube, and upon onsetting the experiment one of the balloons shrinks and the other expands. Here, we present the liquid version of that experiment. We use superhydrophobic (SHP) substrates to form spherical droplets and connect them with a capillary channel. Different droplet sizes, substrates of different hydrophobicities, and various channel pathways are investigated, and morphometric parameters of the droplets are measured through image processing. In the case of SHP substrates, the pumping is from the smaller droplet to the larger one, similar to the two-balloon experiment. However, if one or both of the droplets are positioned on a normal substrate the curvature radius will indicate the direction of pumping. We interpret the results by considering the Laplace pressures and the surface tension applied by the channel at the connecting points. 相似文献
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上游泵送机械密封的基本原理分析 总被引:1,自引:0,他引:1
上游泵送机械密封是利用低压流体实现对高压流体密封的一项新的密封技术,它的典型特征是在一密封端面开有起上游泵送作用的浅槽,利用流体动压效应使得两完整的流体膜分开,这极大地改善了密封端面的润滑状态。本文介绍了分析了该类机械密封的基本原理。 相似文献
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针对循环冷却水作中小型工厂消防水源的技术可行性及在工程设计中需要采取的技术措施等方面的问题进行了探讨和分析 ,并给出循环冷却水作为消防水源不同情况下循环水泵房与消防泵房的平面布置方式 相似文献
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对热参数泵吸附分离床层中的非稳态传热问题进行了理论分析及实验测定,求出了实验范围内的有效导热系数,并给出了从传热角度计算热参数泵吸附分离过程的循环周期时间的关系式.用导出的模型及求出的参数计算出来的温度分布与实测值符合良好. 相似文献
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以辽河油田曙光工程技术处作业大队在曙光采油厂、特油开发公司、冷家油田等区域从事各种油水井小修作业为例,从立式抽油机对油水井小修作业影响因素出发,介绍了立式抽油机在修井作业过程中对作业影响的因素。 相似文献
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机采系统能耗是油田开发生产过程中主要的耗能单元之一,机采系统效率的大小直接影响到油田开发的效果,直接影响油田的经济效益。以提高地面系统效率为目标,以抽油机为主要研究对象来分析提高效率的途径,通过分析得出,双驴头抽油机相对常规游梁式抽油机,其性能优越,运行平稳,是实现节能、高效的优选机型,能够有效提高系统效率。 相似文献
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介绍了一种采用玻璃纤维增强塑料(也称玻璃钢)结构替代混凝土、砖砌结构的新型复合材料泵站井。在理论分析的基础上,对直径为3 m的玻璃钢泵站井进行了强度、刚度及稳定性的有限元分析。结果表明:埋地玻璃钢泵站井环向应力理论分析与有限元分析结果基本吻合,可作为井壁厚度设计的依据;轴向应力理论分析没有考虑加强筋的影响,理论分析与有限元分析误差较大,但其值较小,可不作为井壁厚度设计的控制因素;最小稳定安全系数与加强筋的截面有关,增大加强筋的高度可有效提高泵站井的整体稳定性。 相似文献
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设计了一种利用RS485总线进行数据传输的抽油机监控系统,实现了一台PC机同时监控多个抽油机的工作状况。PC机与进行数据采集的多台单片机通信,从机采用AT89S51单片机进行数据采集,具有实时数据采集、数据显示及记录和超限报警等功能,实现了对抽油机转速、转矩、输出流量、抽油杆应力及环境温度等参数的实时监测,为安全生产提供了保障。 相似文献
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Nayef Mohamed Ghasem 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(6):666-669
In thermal parametric pumping, the temperature change can be imposed through the bed jacket (direct mode) or through temperature change of the fluid stream (recuperative mode). The process to be addressed here is thermal parametric pumping operating in a combined mode of operation by changing the temperature of the fluid stream before entering the packed bed through a heat exchanger (recuperative mode) at the same time as imposing a temperature change through the bed jacket (direct mode). Axial dispersion and the general non‐linear form of the equilibrium isotherm were taken into account in the mathematical model used to verify the experimental results of separating a binary liquid mixture of a benzene/n‐hexane/silica gel system. Copyright © 2003 Society of Chemical Industry 相似文献
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改性木素磺酸盐泵送剂GCL1-3的制备及性能研究 总被引:4,自引:1,他引:3
通过研究缓凝高效减水剂GCL1与保水剂、引气剂的配伍性能 ,研制了混凝土泵送剂GCL1- 3。GCL1与保水剂HEC、引气剂复配时 ,改善了水泥净浆的保水性能 ,提高了硬化水泥的早期及后期抗压强度。实验测试了GCL1- 3的水泥净浆流动度、减水率、流动度损失和抗压强度等性能。结果表明 ,当w (水 )∶w(水泥 ) =0 4∶1 0 ,w (GCL1- 3) =0 .5 %时 ,水泥净浆流动度可达2 30mm ,减水率达 18% ,且无离析现象 ;2h内流动度损失仅为 2 4% ,而掺FDN的净浆已经失去流动性 ;w(GCL1- 3) =0 .5 %时 ,水泥净浆硬化 3d、7d、2 8d的抗压强度比分别达 146 %、15 8%与148% ,均高于使用FDN 相似文献
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An electrochemical two-compartment cell was used to study the photo-induced insertion and transport of hydrogen through a palladium foil covered with a thin layer of the semiconducting thiophene oligomer sexithiophene, which photoelectrochemical current–voltage measurements have characterized as p-type with a photopotential of 200 mV and photocurrents up to 0.3 mA cm–2 at –0.8 V vs. SCE in a pH 3 electrolyte. Upon illumination the flux of hydrogen through the composite electrode was found to increase by a factor of two. The photoinduced enhancement on the hydrogen insertion was not stable since the photoactivity of the material altered under the influence of light. FTIR measurements showed that this is due to hydration of CC-double bonds destroying the conjunctive system of the p-orbitals necessary for the semiconducting properties. Diffusion coefficients of the sexithiophene/palladium electrode were found to be one order of magnitude smaller than in uncovered palladium, which was attributed to the lower hydrogen absorption in the oligomer. The relevance of light induced proton transfer in organic layers for the development of energy converting devices and sensors is discussed. 相似文献