ANALYSIS OF VOLATILE CONSTITUENTS OF CHINESE MEDICINAL HERBS BY FLASH DISTILLATION/CAPILLARY GAS CHROMATOGRAPHY/MASS SPECTROMETRY

In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spectrometry.The results are consistent with those obtained by conventional steam distillation extraction method.The optimum condition of flash distillation has been studied.The experimental results showed that this new technique proved to be a simple,rapid and efficient tool for microanalysis of volatile constituents of Chinese medicinal herbs.

Effectiveness of Automatic Control over Flash Distillation Kettle for Liquid-Phase Bulk Polymerization of Propylene

Automatic control over flash distillation section at SINOPEC Cangzhou Refinery has been realized, resulting in saving of propylene feedstock and emission reduction to harvest significant economic benefits.

Separation of Benzoic Acid Residue by Flash-Vacuum Distillation-Melt Crystallization

A large amount of residue including benzoic acid, benzyl benzoate and fluorenone can form in the production of benzoic acid by oxidizing toluene. To recycle the resources and reduce secondary pollution, the treatment of benzoic acid residue was carried out to obtain the three purified materials by flash-vacuum distillation combination method, and the influence of the operating parameters, such as the top pressure, reflux ratio and top and bottom temperatures was investigated to obtain the best operating conditions. The experimental results show that the benzoic acid purity can reach 97% through distillation under the following conditions: the top pressure is 1 600 Pa, the bottom temperature is 190-200 ℃, the top temperature is 130-135 ℃, and reflux ratio is 5:1. The best operating conditions for benzyl benzoate distillation column are: the top pressure is 400 Pa, bottom temperature is 250260 ℃, the top temperature is 150-160 ℃, and reflux ratio is 5:1. The benzyl benzoate purity can reach 95% and the fluorenone purity can reach 92%. When refined by melt crystallization, the benzoic acid purity can be improved up to 99.6%, and the purities of benzyl benzoate and fluorenone are both above 95%.

基于多级闪蒸与多塔蒸馏耦合的贫氦天然气低温提氦工艺

聚焦从低品位含氦天然气中提纯氦气这一工程问题,在分析已有深冷工艺发展现状与改进方向的基础上,针对原料天然气中氦气浓度低与提氦能耗高的问题,提出一种基于多级闪蒸与多塔蒸馏耦合的贫氦天然气低温提氦工艺,并借助ASPEN HYSYS软件模拟设计了新工艺流程。结果表明:采用设计工艺可从氦摩尔分数为0.05%的贫氦天然气中分离得到纯度(摩尔分数,下同)为99%的氦气,同时得到纯度为99.96%的甲烷和99%的氮气、液化天然气及燃料气,增强了提氦装置的产品方案灵活性;通过工艺内部流股节流膨胀制冷为分离系统提供冷量及工艺内部冷热物流间合理匹配换热,实现了系统的节能降耗;该多级闪蒸+多塔蒸馏耦合工艺的单位压缩功耗为0.058 kW·h kmol,远低于改进型ExxonMobil公司的提氦工艺(1.29 kW·h kmol);综合分析工艺产品纯度及能耗,说明设计的提氦工艺具有一定的应用潜力。

Effect of Bio-Disc on Distillate Yield and Crude Oil Properties

The market worth of the crude oil transported to the international market has a great influence on the crude’s physical properties, as such demands that certain desirable physical properties ought to be possessed. The distillation of crude oil is the first process in the sequence of refining operation and is key to refinery operations profitability. In this work, five crude oil samples were collected from a reservoir in the Niger Delta designated as S11A, S12A, S13A, S14A and S15A. Sample S11A was not treated with bio-disc while samples S12A-S15A were treated with bio-disc at different number of times. This was necessary to ascertain the effect of the bio-disc on crude oil physical properties and their distillate yield. After the treatment, the specific gravity, American Petroleum Institute (API), pour point, flash point and viscosity of the treated and untreated crude samples were determined and then the samples distilled with a distillation tester. From the results obtained, the bio-disc had a great influence on the physical properties of the samples as well as on the distillate yield. The specific gravities of the oil samples decreased as the number of times the samples were treated with bio-disc increases and this in turn increased the crudes’ API. The pourpoint and viscosity decreased with increase in number of treatments of crude samples with bio-disc. As the number of treatments increased, the crude samples which were originally paraffinic were tending towards being naphthenic. The flash point and distillate yield increased with increase in number of treatments of crude samples with bio-disc. Thus, treatment of crude oil with bio-dic alters the physical properties of the crude.

太阳能热脱盐的途径和应用研究

太阳能热脱盐(Solar thermal desalination,STD)是一种极具潜力的低能耗、可持续海水淡化新方法,可用于在能源基础设施不完备的干旱地区生产清洁淡水。目前,通过改进太阳能吸收材料和系统设计来提高STD效率受到越来越多的关注。系统地介绍了各类高效光热转换材料的特点及其在利用太阳辐射进行海水淡化方面的应用,然后从隔热结构和冷凝结构设计等不同的角度讨论了STD系统的热能管控措施,并进一步阐明了潜热回收的重要性,最后,总结了STD系统工艺现有的局限性和提高STD系统脱盐效率的有效途径,并对STD系统的实用性和经济性进行了展望,以期为开发更高产水率、更低能耗的可再生能源脱盐新工艺提供参考。

基于图卷积网络的柴油加氢生产软测量建模

精制柴油闪点和石脑油终馏点是柴油加氢生产最重要的质量指标,但目前缺乏测量这两种指标的在线分析仪表,软测量是可行的替代方案。为完成这两种指标的软测量建模,分析柴油加氢生产过程的工艺机理和过程数据特征,完成了辅助变量的重构和筛选,确定了两个软测量对象的辅助变量集,基于图卷积网络建立闪点和终馏点的软测量模型进行仿真研究。仿真研究结果表明:相比于目前应用广泛的软测量模型,所提出的软测量方法具有更高的精度,可以提升柴油加氢生产软测量建模的有效性和准确性。

蒸发法处理高浓度含盐废水的工艺对比分析

主要介绍了蒸发法处理高浓度含盐废水的三种工艺,即多级闪蒸技术、多效蒸发技术、机械蒸汽再压缩技术。上述三种工艺在处理高浓度含盐废水方面各有利弊,其中,多级闪蒸技术不易结垢,适宜处理含高浓度结垢离子的废水,多效蒸发技术相较于单效蒸发技术而言,利用了二次蒸汽,使系统能耗在一定程度上降低。机械蒸汽再压缩技术能再次利用二次蒸汽的潜热,大大提高了能量利用率,能耗相对其他技术最低,且运行成本低。最后对未来的工艺和技术改进方向进行了展望,并为解决高浓度含盐废水的技术难题提供了指导。

Chemical Properties,Low-Temperature Performance,and Burning Performance of Bio-Jet Fuel

The effects of composition of bio-jet fuels on freezing point,smoke point,distillation range,and flash point are investigated.Performance tests using petroleum-based jet fuel with different compositions are conducted in line with standard test specifications.The results show that alkylbenzenes reduce the freezing point,with the amount of reduction becoming greater with increasing alkylbenzene content.For a 25%content of the C_8 aromatic xylene,the freezing point is in the range from-55.5℃to-60.1℃.The presence of monocyclic aromatic hydrocarbons leads to an increase in carbon deposition performance,especially when alkyl side chains are present.With cycloalkanes,carbon deposition is reduced,although alkyl side chains weaken this beneficial effect.Isomeric hydrocarbons are beneficial in reducing carbon deposition.The ASTM D7566 specifications for the distillation range are based on the average properties of petroleum-based aviation fuel,and if all the parameters governing the distillation range of an alternative jet fuel are at their lower limits,it is necessary to check whether other performance standards are met.Light components affect the flash point greatly,with 5%of benzene reducing the flash point by 17℃,whereas intermediate components(e.g.,xylene and ethylbenzene)and heavier components have less impact.Although alcohols provide better combustion performance,their content must be strictly limited owing to their effects in reducing the flash point.

不同原油稳定工艺模拟对比与分析

为提高原油稳定工艺的稳定深度、能耗水平和经济效益,以现场实际运行工况为例,从稳定深度、C_(1)~C_(4)拔出率、单位产品能耗、经济效益和工艺㶲损失等方面出发,利用HYSYS模拟软件和PR状态方程,对微正压闪蒸工艺和提馏稳定工艺进行对比和分析,确定了不同工况下的工艺边界条件。结果表明,对于微正压闪蒸工艺和提馏稳定工艺,塔底温度应分别控制在90~120℃、110~140℃,以满足原油稳定深度的要求;当对稳定原油中C_(1)~C_(4)的拔出率有所要求,可优先采用提馏稳定工艺;塔底温度对两种工艺的稳定原油单位产品能耗影响不大;与提馏稳定工艺相比,微正压闪蒸工艺在稳定轻烃上的单位产品能耗更小;2000元/的稳定轻烃价格可以作为经济上优选工艺的分界点;从工艺上分析,原油稳定工艺的重点优化对象为换热器、加热器和塔器。研究结果可为同类原油稳定工艺的优化设计提供参考。

闪蒸/气相色谱/质谱法定性定量分析烟叶中香味物质的研究

采用闪蒸 /毛细管气相色谱 /质谱法 (Flash- Distillation/ GC/ MS)对烟草中的挥发性香味物质进行了分析研究 ,共鉴定了烟草中70余种挥发性成分。对我国主要烟区不同类型、不同等级的烟叶和国外不同等级的白肋烟叶中的挥发性香味物质进行了定性定量分析。结果表明 :对不同类型烟叶样品挥发性香味物质的分析 ,在定性和定量上均有差异 ;对同种类型、不同等级的烟叶样品挥发性香味物质的差异 ,大都在定量上 ,并无定性上的差异。该方法具有分析速度快、操作简便、重现性好等特点 ,适用于烟草挥发性香味成分的分析。

生物油轻质馏分加氢试验研究

本文基于分子蒸馏设备对流化床快速热解试验装置所产生物油进行预分离,得到的轻质馏分在固定床加氢微反应装置上进行Ru/γ-Al_2O_3催化的加氢精制研究,分析了反应温度(60～140℃)、氢气压力(常压～3 MPa)和进料速率(1.5～4.5 ml/h)对反应产物组分分布的影响规律.研究结果表明,通过加氢精制后,生物油轻质馏分中不饱合化合物在大于120℃的反应条件下得到完全转化;醇类化合物的种类有所增多.

太阳能闪蒸-多效蒸发海水淡化系统研究

针对传统太阳能海水蒸馏淡化方法,综合多级闪蒸和多效蒸发两种系统的优点,设计制造了具有一效蒸发器的太阳能闪蒸-多效蒸发海水淡化装置,并对该装置进行了试验。试验结果表明,系统在海水温度为68~78℃范围内正常运行,具有较高的日产水量,系统达到稳定的时间较短。在闪蒸压力0.014 MPa,蒸发压力0.004 0 MPa条件下,最高海水温度为78℃时,系统产水量为56.30 kg/d,16 min就可以稳定。系统压力不变时,最高海水温度变化,而系统内部温度不变,比较适合太阳能热源不稳定情况。

海水淡化的现状与未来

本文介绍了近年来主要海水淡化方法—— SWRO、MSF、MED的某些新进展。海水淡化市场的激烈竞争和海水淡化技术进步 ,尤其是 SWRO的进展 ,使淡化的能耗下降了近一半 ( 3k Wh m3以下 ) ,产水的出厂价也几乎下降了一半 ( 0 67美元 m3)。近两年大型海水淡化厂的国际招标中 ,SWRO以低投资费、低能耗、低产水价而占上风。预计 2 1世纪的海水淡化市场会有很大发展 ,SWRO将是主要的海水淡化方法。

提高塔河原油所产沥青闪点的技术研究

针对塔河原油所产沥青闪点低的情况,对影响沥青闪点的因素进行分析,并提出提高沥青闪点的措施。通过分析塔河原油的性质,并与科威特原油性质进行比较,认为沥青质含量过高是导致减压渣油闪点低的主要原因。通过优化原料及工艺,采用塔河原油掺炼催化裂化油浆的强化蒸馏技术,可显著提高沥青产品的闪点。将所得减压渣油再与SBR母液调合,可生产高品质的道路石油沥青。

MSF/RO/ED海水淡化技术研究

综述了世界水资源形势以及海水淡化技术的发展现状,概括了海水淡化技术的主要方法,着重介绍了多级闪蒸海水淡化法(MSF)、反渗透法(RO)和电渗析法(ED),从各种装置的组件、能耗以及淡化过程等入手,总结3种方法的优势与不足,针对性提出了解决问题的方法以及发展方向,以降低使用成本,并探讨和展望了今后的海水淡化技术。

船用闪蒸-蒸发海水淡化系统的建模与热力分析

针对舰船发动机排放的烟气具有温度高、热容大的特点,结合闪蒸法和蒸发法海水淡化方法,设计了利用发动机烟气余热的闪蒸-蒸发海水淡化系统。建立了各主要设备的热力计算模型,根据设备之间的连接组合关系以及物流传递关系,建立了海水淡化系统的稳态数学模型,利用序贯模块法顺序求解,可实现系统的稳态模拟。模型中考虑了海水温度变化对系统性能的影响,提高了仿真精度。通过实例研究,获得了海水淡化系统的淡水产量与海水流量、系统压力的关系,研究结果表明该海水淡化系统具有较好的运行性能,可满足中小型船舶对淡水的需求,具有良好的节能效果和经济效益。

海水淡化过程优化设计的研究进展

海水淡化是能源密集型工业,对淡化工艺、操作参数及设备结构等进行优化设计是降低淡化过程能耗的有效途径。本文分析了不同海水淡化方法的技术特点,详细介绍了海水淡化过程的优化设计方法及海水淡化技术集成的研究进展。

我国6种主要原油及其直馏馏分3种蒸馏曲线的关系

根据我国大庆、华北、胜利、孤岛、中原和克拉玛依６种主要原油及其馏分油３种蒸馏过程实测的６４组平衡闪蒸数据，实沸点蒸馏及馏程试验各２０９组实测数据，提出了适合６种油的３种蒸馏换算式２１个，及相应的６张算图，算式中除３个式子外，其余１８个算式绝对平均偏差均低于ＡＰＩ图表偏差。

高含硫净化装置胺液系统的运行及优化

高含硫净化装置在运行过程中,N-甲乙醇胺(MDEA)溶液发泡问题变得得为突出.该工况容易造成装置后路气相带液.严重时会引起冲塔。通过观察装置运行参数.判断总结出MDEA发泡的主要依据是吸收塔的压差上升。结合现场实际操作,发现引起MDEA溶液发泡是各种部题多样化的结果.分别给出解决MDEA溶液系统发泡部问题的技术方案。通过对联合装置加入阻泡剂、清洗过滤系统机械过滤器、及时更换活性炭过滤器的活性炭、调整重沸器蒸汽入口的温度等,减小了胺液发泡造成的生产波动及胺液的跑损,实现了除去胺液的杂质和减少胺液降解等目标.得出了详尽的实验数据。数据分析表明该方案取得了较好的生产效果.达到了降耗目的。