Effect of cyclohexanol on phase stability and volatility behavior of hydrous ethanol-gasoline blends

Biofuels can contribute to reducing greenhouse gas emissions and bridging the gap between production and consumption. Ethanol is a renewable source of energy. It can reduce oil dependence and also can be appropriately used in gasoline as a blend. The high cost of dry ethanol has turned the researcher's attention to the more economic hydrous ethanol. However many works were focused on its impact on the engine performance and the exhaust emissions; few works were interested in the phase stability of those blends. This work aims to study the impact of blending cyclohexanol (CH) into hydrous ethanol-gasoline blends as a stabilizing agent. Four dual-alcohol (E5-3CH, E10-3CH, E15-3CH, and E20-3CH) blends were investigated besides their single hydrous ethanol (E0, E5, E10, E15, and E20) blends. The tests involved; water tolerance, distillation curve, and vapor pressure. Vapor lock protection potential, the area under the distillation curve (AUDC), and the area due to azeotrope formation (ADAF) were calculated. The obtained results show that cyclohexanol significantly increases the water tolerance of hydrous ethanol-gasoline blends. The blends of E5 and E10 which were separated at 30 °C converted into miscible and clear samples when they were blended with 3 vol% of cyclohexanol. These samples can also tolerate additional water. For E20, the addition of 3 vol% of cyclohexanol increased the water tolerance by about six times. Also, it was found that cyclohexanol does not have any negative effect on the volatility properties of the fuel blends. It was found that blending CH into the hydrous ethanol blends causes a significant increase in the AUDC and consequently, the area due to azeotrope formation (ADAF) decrease.     

Optimization of crude oil refining products to valuable fuel blends

Crude oils are composed of hundreds of different hydrocarbon molecules, which are separated through the process of refining and small quantities of oxygen, sulfur, nitrogen, vanadium, nickel, and chromium. An oil refinery is a group of manufacturing plants that are used to separate petroleum into valuable fractions. Oil refining is one of the most complex chemical industries, which includes many different and complex processes with several possible connections. In the process of distillation, crude oil is heated in a furnace so that hydrocarbons can be separated via their boiling point. The main purposes of crude oil blending are to optimize commercial value, to upgrade or reduce oil consumption to meet specifications and to facilitate oil movement. Simulation software, such as linear programming modeling, is often used to estimate the rate components that provide a low cost mix. The aim of blending of crude oils and refinery products is to increase the refined margins without affecting the required physical properties of the blends. The optimization of in crude oil blends and maximization of low-cost refinery intermediates in final blends are the basic processes for achieving this goal of using cheap crude oils. The highest degree of blending optimization requires continuous updating of the simulation model by adapting to real-time analytical trends.     

Effect of ethyl acetate addition on phase stability,octane number and volatility criteria of ethanol-gasoline blends

Blending ethanol in gasoline causes problems related to volatility and phase stability of the fuel blends. Ethanol is completely miscible with water so it has high affinity to water that may be present in storage tanks or that formed due to humidity. Drop in ambient temperature influences the stability of ethanol-gasoline blends and causes phase separation to the blend. This phase separation cause disadvantages like: poor quality fuel, loss in cost, and damage to storage tanks and engine parts due to corrosion. In this work, Ethanol-blended gasolines E5, E10, E15, E20 and ethanol-free gasoline (E0) were formulated to study the effects of ethyl acetate addition on these fuels. The obtained results revealed that the addition of ethyl acetate to ethanol-gasoline blends has many advantages such as enhancing the stability of the fuel blends and improving octane number with no adverse impacts on the volatility criteria of the investigated fuel blends.     

几种不同分子结构柴油降凝剂的降凝效果及其复配物的协同效应

研究了几种不同分子结构柴油降凝剂的降凝效果及其复配物的协同效应。结果表明:降凝剂的成核性能以及分散性能主要取决于其分子结构,其分子结构类型对不同降凝剂复配物在柴油中的协同效应有重要影响;透射电镜(TEM)分析结果显示,乙烯-乙酸乙烯酯共聚物(EVA)的成核性能较好,甲基丙烯酸十四酯-马来酸酐-甲基丙烯酰胺三元共聚物(MC14-MA-MCNR1R2)的分散性能较强,二者复配后在柴油中具有较好的降凝点和降冷滤点效果。在该复合降凝剂作用下的石蜡晶体颗粒分散均匀,且颗粒变小,约95%的粒径为30~40 nm。借助TEM,用冷冻蚀刻法研究柴油的结晶形态以及降凝剂对柴油中石蜡晶体的作用机理是一种非常直观有效的途径。     

车用乙醇汽油的储存和使用

阐述了推广使用车用乙醇汽油的意义，介绍了车用乙醇汽油在加油站的储存要求，总结了车用乙醇汽油在使用过程中常见的一些问题、解决方法及车用乙醇汽油在使用中的注意事项。     

加油机液压系统产生气阻的原因及对策

分析了加油机产生气阻的原因，提出了避免产生气阻的方法，指出应按照加油机的结构参数合理设计、正确安装加油机，注意多枪加油机的使用，吸油管线的长度、焊接质量和弯头数量，以及安装的高度等问题。     

Extension of gas adsorption models to liquid diesel fuel desulfurization: Validity and predictability

Desulfurization of diesel fuel is simulated in a fixed-bed adsorption column. Researchers have paid less attention to models that describe and predict liquid phase adsorption. Hence, the ability of five widely used models which were originally developed for gas adsorption (Zhang–Cheng, Clark, Thomas, Bohart–Adams, and Wolborska) to simulate and predict the fuel desulfurization breakthrough curve is investigated. Afterward, the best model is chosen to predict the breakthrough curve in different flow rates and bed depths. An industrial scale-up with a real refinery flow rate using the appropriate model has been done. The results are in good agreement with the reported ones.     

加氢法制备生物航煤的现状及发展建议

综述了加氢法制备生物航煤的原料来源（油脂）、两段加氢技术和生物柴油联产生物航煤技术的进展及产业发展现状,并对我国生物航煤的近远期原料来源、催化剂等关键技术的开发利用、产品标准的制定及生物质气化－ＦＴ合成技术的开发提出了相关建议。     

Catalytic co-cracking of waste polypropylene and residual fuel oil

Abstract

Industrial waste polypropylene (PP) homopolymer and residual fuel oil (RFO) were pyrolyzed together in presence of catalyst ZSM-5 under the atmospheric pressure with different mixing ratios of the feedstocks. The experiments were carried out in a batch reactor at two different temperatures of 500?°C and 600?°C with the blended mixture (PP/RFO) to catalyst (ZSM-5) ratio of 4:1. The effects of blending ratios between the two feedstocks and temperature with respect to the yield of the products oil, gas, and residual coke were determined. The optimum blending ratio of PP and RFO with respect the higher quantity yield of liquid product was found to be 1:1 at 500?°C. The percentages of liquid fuel, gas, and coke were observed to be 74.8%, 10.2%, and 15% at 500?°C.     

乙烯装置裂解炉燃料气系统的平衡与优化

通过分析某乙烯装置燃料气系统运行现状及影响因素,阐述了燃料气平衡思路和多项优化调整措施。通过外补天然气、外补碳四和系统动态优化调整等方法,提高了燃料气管网运行稳定性,避免出现排放火炬情况,达到节能减排、提高经济效益的目的。     

Preparation and properties of oil-substituted fuel based on petroleum coke with biomass fermentation

To improve the stability of petroleum coke water slurry (PCWS), bubble-PCWS based on biomass fermentation was researched in this paper. The results showed that the stability of bubble-PCWS improved as biomass dosage increased. The bubble-PCWS with yeast could reach a high solid concentration of 65?wt% and a perfect stability with water segregation rate being 0?wt% and pour out rate being more than 90?wt%, when the straw dosage was 3?wt%. The bubble-PCWS with activated sludge possessed good recoverability, but the solid concentration and the pour out rate obviously decreased as the sludge increased.     

柴蜡油混合进料加氢裂化装置试产军用3号喷气燃料

目的提高柴蜡油混合进料加氢裂化装置生产的3号喷气燃料中芳烃含量,使之能达到军用3号喷气燃料产品的要求。 方法通过提高混合原料中蜡油比例和混合原料油密度、降低精制反应器床层温度、优化裂化反应器级配催化剂床层温度及降低芳烃加氢饱和深度的方式,提高3号喷气燃料中芳烃含量。 结果①在处理量不变的情况下,通过提高原料中蜡油比例和混合原料油密度,可显著提高喷气燃料中芳烃含量;②在高柴油比例原料的工况下,通过大幅降低精制反应器床层温度、同步降低轻油型催化剂床层温度及提高灵活型和中油型催化剂床层温度的方式,降低了芳烃加氢饱和程度,使喷气燃料产品中芳烃体积分数≥8%,同时确保尾油BMCI值小于13。 结论通过提高混合原料蜡油比例和混合原料密度至一定数值以及降低精制反应器床层温度和芳烃加氢饱和深度的方式,可实现喷气燃料产品中芳烃体积分数≥8%的目标,解决了柴蜡油混合加氢裂化装置生产军用3号喷气燃料的问题,具有一定的生产指导意义。      

喷气燃料/柴油混合燃料燃烧及颗粒物特性

为研究柴油机燃用喷气燃料/柴油混合燃料燃烧及排放颗粒物特性,配制喷气燃料(RP-3)掺混体积分数20%、40%、60%以及纯柴油的4种燃料(D80K20、D60K40、D40K60、D100),通过台架试验研究了缸内燃烧过程,采集了颗粒物,利用透射电镜、拉曼光谱仪、热重分析仪对不同掺混体积分数混合燃料排气颗粒的物理化特性进行研究。结果表明：与D100相比,D80K20、D60K40、D40K60缸内最高燃烧温度增加幅度小于11℃,缸内压力变化不大,压力峰值对应的曲轴转角后移1.35～2.16°CA,滞燃期延长0.39～1.64°CA,燃烧持续期缩短0.21～0.86°CA;颗粒总体排列呈现链状或枝状,不同RP-3掺混体积分数(D100、D80K20、D60K40、D40K60)下颗粒的计盒维数分别为1.8569、1.9386、1.9563、1.9836,D₁峰与G峰的比值(I_D1/I_G)分别为1.09、1.03、0.92、0.85,随着RP-3掺混体积分数的增加,颗粒物堆叠程度略有增加,颗粒物表面碳排列更加有序,颗粒物的...     

Influence of alkyl methacrylate-maleic anhydride-1-hexadecene terpolymers and their mixtures with ethylene-vinyl acetate as pour point depressants in diesel fuel

In this paper, tetradecyl methacrylate-maleic anhydride-1-hexadecene (C₁₄MC-MA-HE) terpolymers in various molar ratios was prepared and used as pour point depressants (PPDs) in 0^# diesel fuel. Results showed that C₁₄MC-MA-HE terpolymers exerted distinct depression effects on solid point (SP) and cold filter plugging point (CFPP) at 0.15?wt.%, especially in 4:1:1 and 4:4:1 ratio. To obtain better PPDs, the terpolymers were mixed with ethylene-vinyl acetate copolymer (EVA) at 1:1 mass ratio, and have proved to present better synergistic effects. PPDC-2 exhibited the best depression in both CFPP and SP by 20?°C at 0.15?wt.%. Additionally, the performance mechanism was explored.     

Kinetic modeling and experimental study on the combustion,performance and emission characteristics of a PCCI engine fueled with ethanol-diesel blends

The combustion process in the Premixed Charge Compression Ignition (PCCI) engine is basically restricted by the in cylinder charged mixture components. Also, the homogeneity of the charged mixture is determining the quality and process of the chemical reaction during the first stage of combustion which establish the auto-ignition process. In the present work, the engine experimental setup is equipped with a new suggested modification on the original fuel system device in order to produce a perfect commixture of diesel/ethanol at different blends ratio with the charged air. The obtained laboratory results are used to validate the simulation's data of the PCCI engine ignition. The prediction is performed using a detailed kinetic reaction mechanism. The simulation study has been achieved to predict the auto-ignition timing and the combustion characteristics of the PCCI engine fueled with different blends of ethanol and diesel at different volume percentage. The obtained results show that the premixed ratio of the ethanol in the ethanol/diesel fuel blends can be used to control the auto-ignition timing and the combustion characteristics at different engine air/fuel ratios. Also, the main pathway of this work is to establish the influence of the engine operating parameters which including the premixed ratio, fuel–air equivalence ratio on the engine performance, combustion and emission characteristics of the PCCI engine. These effects are studied and traced through the simulation result data of the in-cylinder pressure, temperature, and gas phase heat release at different a premixed ratio of ethanol-diesel fuels blends of 0, 10, 20, 30,40 and 50% (by volume).     

高压下乙炔水合物的形成与分解实验研究

气体水合物是水和气体在高压低温下形成的一种笼形结晶化合物,具有强大的储气能力。关于水合物的形成、性质特征及能源利用、储存方面的研究日益受到重视,进行水合物研究的实验装置和测试技术也在不断发展,目前多数研究侧重于甲烷、二氧化碳等气体的水合物,对乙炔气体水合物的详细研究未见相关报道。文章基于自行设计的水合物合成及原位观测装置,采用化学反应生成气体的方法提供乙炔气源,在此基础上对乙炔水舍物合成的条件进行讨论,得出了乙炔形成与分解规律的初步结果,可为进一步研究乙炔水合物及应用于乙炔气体的储运等提供参考。     

柴西地区地温-地压系统特征及其与油气分布的关系

柴西地区地温梯度分布范围为每百米2.0-4.5℃,平均值约为每百米3.1℃。在2300 m深处开始发育异常高压, 压力系数最高可达2.0。按照地层压力系数及地温异常的分布区间,柴西地区温压系统在平面上划分为高温高压等9个分区,在纵向上分为上部常压型温压系统及下部超压型温压系统。上、下两套温压系统流体能量差较大,油气垂向运聚能力较强,易于在温压系统分界面附近聚集成藏。平面上,油气藏基本位于流体能量相对较低的分区内,高流体能量区也有油气藏分布,但大多为封闭保存条件好的岩性及构造-岩性等原生油气藏。现今温压系统特征表明,深层高压型温压系统油气封闭条件好,赋存有大部分油气资源,是今后油气勘探的重要领域。