Recovery of vinyl chloride from by-streams of polyvinyl chloride production by TPSA in a multitubular adsorber

This work aims at developing an efficient and feasible adsorption-based separation process for the separation of vinyl chloride and nitrogen, on activated carbon, by employing a multitubular packed bed geometry, with adsorbent material inside the tubes. Using this geometry, a 2-dimensional mathematical model of a temperature pressure swing adsorption process was used to developed a 6-step three multitubular adsorbers system capable of separating and purifying an industrial scale gas stream of a 40:60% (v/v) vinyl chloride/nitrogen mixture into a 95% (v/v) vinyl chloride stream and a nitrogen stream with a vinyl chloride limit concentration of 8 ppm (w/w). The process reported energy consumption of 4.88 × 10⁶ J/kg_VCM and recovery capacity of 24.35 kg_VCM/(m³_unit h). The multitubular geometry enabled the use of lower adsorbent loads, shorter cycle times, and lower regeneration temperatures. An equivalent 1-dimensional model has also shown to satisfactorily estimate the performance of the current equipment.     

通用型液压马达实验台的分析与设计

通用型液压马达实验台的检测实验装置能够模拟实际工况对不同类型、多种规格的液压马达进行性能测试。设计一种通用型液压马达,包括实验台的连接支架设计、转速扭矩仪选型、负载系统设计、油箱设计及油路优化,并对设计参数进行了计算与有限元验证。该实验台可按照国家标准和检测方法,对多种类型不同型号液压马达做性能测试。     

平行流式电机周向水套结构参数对散热性能影响研究

针对电力机车上某功率密度为1.27 kW/kg的平行流式电机周向水套结构的散热问题进行了研究。首先利用热阻网络法建立了平行流多通道截面的热阻数学模型;然后借助FLUENT软件对水套的电机散热过程进行了数值模拟,并对结构参数进行了优化;最后通过实验验证了计算的正确性。结果表明:当通道孔数n增大时,总热阻普遍减小;当通道单孔宽度x增大时,总热阻先增大后减小,当n=6个、x=1.670 mm时,水套具有最佳的散热性能;水套各测温点的数值模拟温度与实验测量温度之间的相对误差均低于5.00%。     

可控中高软压光控制策略分析

可控中高软压光具有纸面整饰作用,可大幅提高纸张平滑度、光泽度。重点介绍可控中高软压光系统组成、工作原理及液压系统组成。研究其控制策略并应用ESC700系统实现其控制过程。     

掘进机电液双控系统的研究

 在掘进机智能化发展过程中，远程遥控和机载控制并存状态是必不可少的。掘进机一般采用电液双控系统来实现该功能，但实践中采用电液双控系统会出现液控动作缓慢的问题。当掘进机装载运输同时动作并采用液控操作时，装运马达转速缓慢甚至停转，严重影响正常工作。结合现场故障现象，分析掘进机电液双控系统的工作原理及各元件原理，排除故障并进行深入研究。基于现有技术条件，提出改造方案并选择可行方案试验，最终从根本上解决问题。     

液压支架侧推弹簧合理工作负荷设计

弹簧是制约液压支架侧护板能否顺利弹出的关键因素之一,其工作负荷设计得是否合理至关重要。建立了4种常见的侧推千斤顶和弹簧布置方式的侧护板弹出力学模型,分析了系统回液背压、千斤顶启动压力、摩擦力、布局等因素对侧护板弹出的影响,给出弹簧最小工作负荷的计算公式,得出系统回液背压和千斤顶启动压力是造成侧护板弹不出的主要原因,两侧的侧推千斤顶与弹簧之间的距离相等是保证每根导杆均匀弹出的必要条件,尽量避免采用交叉布置方式。     

Simulation and analysis of dual-reflux pressure swing adsorption using silica gel for blue coal gas initial separation

A dual-reflux pressure swing adsorption (DR-PSA) process was proposed and simulated to initially separate the blue coal gas, aiming to capture carbon dioxide (CO₂) and enrich hydrogen (H₂), simultaneously. With a feed flow rate of 7.290 slpm, a light product reflux flow rate of 0.505 slpm and the heavy product reflux flow rate of 3.68 slpm, the developed DR-PSA process could capture CO₂ up to 64.01% with a recovery of 99.60% and enrich H₂ up to 34.66% with a recovery of 97.63% from the blue coal gas (36.2% N₂/28.5% H₂/13.9% CO/12.7% CO₂/8.7% CH₄). In addition, in order to optimize the process, the effects of various operating parameters on the DR-PSA process performance in terms of product purity and recovery were discussed in detail, including the feed position, the light product reflux ratio and the heavy product reflux ratio. Moreover, the dynamic distribution behaviors of pressure, temperature and gas-solid concentration were presented to explain and evaluate the process separation performance in depth under different operating conditions.     

水平井分段体积压裂复杂裂缝形成机制研究现状与发展趋势

水平井分段体积压裂是油气储层中复杂裂缝网络形成的重要技术之一，准确了解复杂裂缝网络形成机制、预测复杂裂缝网络形态对非常规油气资源高效开发具有重要意义，同时也是水力压裂设计优化的理论基础。围绕非常规储层复杂裂缝形成机制，国内外学者根据"应力阴影"效应对水力裂缝同步扩展、水力压裂顺序对多裂缝动态延伸影响、层理面对水力裂缝纵向扩展遮挡效应和天然裂缝与水力裂缝交互动态等方面，分别建立了相应的水力压裂模型，并从数值模拟角度对其进行了定性分析。通过总结国内外研究现状，并从模型建立假设条件、数值模拟模型思想和模型局限性3方面对现有模型进行了剖析，并对未来研究方向提出了建议，研究结果可对未来水力压裂复杂裂缝形成机制研究提供借鉴。