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《精细与专用化学品》2017,(5)
对1万t/a异戊烯装置设计的优化项目进行了考察,验证了设计的有效性;分析了装置运行情况,提出了不同负荷下醚化操作的优化条件;优化了醚解催化剂的投用条件,减少了二甲醚的生成,降低了装置的甲醇单耗;控制异构化反应器的温度和叔戊醇含量,保证了2-甲基-1-丁烯的转化率,提高了产品中的2-甲基-2-丁烯的含量;异戊烯侧线出料口下方增加了1米填料后改善了产品的品质,降低了产品中其他组分的含量;装置的标定表明:装置能稳定运行,数据可靠,达到了设计指标。 相似文献
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介绍了螺旋滚筒洗煤机的组成、结构,工艺流程及工作原理,针对存在的问题进行了分析,并采取了相应的技术改造。改造后经过长时间、多个洗煤厂的检验,解决了螺旋滚筒洗煤机存在的技术问题,提高了洗后煤的煤质,避免了矸石含煤并减少了跑货现象,增加了洗煤量及经济效益,使洗煤生产达到了正常。 相似文献
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The grand canonical Monte Carlo (GCMC), the canonical Monte Carlo by using equal probability perturbation, and the molecular dynamics (MD) methods were used to study the capillary phase-transition (capillary condensation and evaporation) and self-diffusion for a simple Lennard-Jones model of ethylene confined in slit carbon pores of 2.109 nm at temperatures between 141.26 K and 201.80 K. The critical point of capillary phase-transition was extrapolated by the critical power law and the law of rectilinear diameter from the capillary phase-transition data in the near critical region. The effects of temperature and fluid density on the parallel self-diffusion coefficients of ethylene molecules confined in the slit carbon pores were examined. The results showed that the parallel selfdiffusion coefficients in the capillary phase transition area strongly depended on the fluids local densities in the slit carbon pores. 相似文献
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Hydrodynamics of Taylor flow in noncircular capillaries 总被引:1,自引:0,他引:1
Dingsheng Liu Shudong Wang 《Chemical Engineering and Processing: Process Intensification》2008,47(12):2098-2106
In this work, volume of fluid (VOF) technique, one computational fluid dynamics (CFD) method, was used to investigate the upward Taylor flow in vertical square and equi-triangular capillaries. For saving computation time, the simulations were carried out in a moving frame of reference attached to Taylor bubbles. The main flow parameters, involving bubble size and shape, liquid film thickness, velocity field and two-phase relative velocity, were studied as functions of capillary number. The numerical simulations were in good agreement with previous reports and showed that the flow in the sides and corners of polygonal capillaries were different. A comparative study was also conducted on Taylor flow in square and equi-triangular capillaries and their circular counterparts, where the influence of capillary geometry on the characteristics of Taylor flow was illustrated clearly. 相似文献
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胶束毛细管电泳法测定有机磷农药的研究 总被引:3,自引:0,他引:3
本论文着重研究了毛细管胶束电泳-紫外检测氧乐果、乐果、敌百虫的分析方法。采用胶束电动毛细管色谱法(MEKC)技术对这三种有机磷农药进行分离,并研究了分析电压、表面活性剂十二烷基硫酸钠(SDS)、电泳缓冲溶液浓度、有机改性剂(甲醇)、进样时间及pH值等对分离测定的影响。当分离电压为20kV,检测波长195nm,在pH值为8.50的150mmol/L硼砂-150mmol/L硼酸的缓冲液与11mmol/L十二烷基硫酸钠和4%甲醇的混合溶液中,在30mbar下进样15s的最佳条件下,3种有机磷农药在最短时间内达到基线分离。在优化条件下,用MEKC方法进行测试。它们的检测限分别为0.11μg/ml、0.06μg/ml、0.10μg/ml。迁移时间和峰高的变异系数分别为0.75%~1.9%、0.44%~0.76%。 相似文献
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A numerical approach, named TransChlor, is proposed to simulate transport phenomena of various substances in concrete. This approach is a theoretical model based on finite elements and finite differences methods. The model consists of coupled nonlinear partial differential equations based on Fick's diffusion law and on kinematics equations. Simulation results from a parametrical study highlight the influence of microclimatic conditions, exposure to deicing salts and concrete cover permeability and thickness on chloride ingress in concrete. The results show that the chloride ion concentration increases quickly in concrete cover when a structure is exposed to deicing salts at a mountainous location; whereas permeability of concrete cover is an insignificant parameter when the concrete is in direct or splash water contact. 相似文献
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