Extraction of El-Lajjun Oil Shale

Abstract

Extraction of the bitumen fraction of El-Lajjun oil shale was carried out using 17 different solvents, pure and combined. Out of all the solvents used, toluene and chloroform were found to be the most efficient for extraction of the bitumen to perform the major part of the experiments. This selectivity was based on the quality and quantity of the yield and on the quantity of solvent recovered. Extraction was carried out using a Soxhlet extractor. For complete recovery of solvent the extract phase was subjected to two stages of distillation, simple distillation followed by fractional distillation, where different cuts of oil were obtained. It was found that an optimum shale size of 1.0 mm offered better solvent recovery. One hour was the optimum time needed for complete extraction. The yield of oil was determined from the material balance gained from fractional distillation after testing for the existence of any traces of solvent trapped in the different cuts by using a gas chromotography technique. When chloroform was used, it was found that the average amount of bitumen extracted was 0.037 g/g of shale, which corresponds to 98% of the actual bitumen trapped in the oil shale (by assuming the bitumen represents 15% of the organic matter) and 84.1% of solvent recovered. When toluene was used, it was found that the average amount of oil extracted was 0.0293 g/g of shale, which corresponds to 78% of the actual bitumen trapped in the oil shale (by assuming bitumen represents 15% of the organic matter) and 89.9% of solvent for extraction with toluene.     

Enhancement of solar water distillation process by surfactant additives

The presence of surfactant additives in water is found to enhance the boiling heat transfer significantly. The effect of using a surfactant as sodium lauryl sulfate (SLS) in relatively small dosages of concentration with a small size unit of solar water distillation process is investigated. Sun simulator (electric heater and variac transformer) is used to quantify the same input power for each experiment for the system instead of the sun. The experimental results show that a small amount of surfactant additive makes the top brine temperature (TBT) considerably higher, hence the freshwater product. Temperature curves for various surfactant concentrations are obtained and compared. The percentage of the increase in the system productivity is 0.7%, 2.5%, 4.7% and 7% at additive concentration equal to 50, 100, 200 and 300 ppm respectively. It is found that increasing the surfactant concentration more than 300 ppm not affecting the system daily productivity (DP) and TBT. Using surfactant concentration more than 400 ppm will decrease the DP by 6%.     

能量集成常减压系统的简捷模型及优化

针对常减压装置,提出基于Fenske-Underwood-Gilliland方程和焓衡算的简捷模型对现有的常减压系统复杂塔进行操作型计算和优化,并利用夹点分析确定系统的热回收目标。以常减压系统的年净利润最大为目标,同时考虑系统的产品收益和能量集成,建立了基于PSO随机粒子群算法的优化方法。以现有的常减压装置为算例,得到了年净利润最大条件下的各工艺参数。通过与严格模拟对比,表明常减压系统简捷模型能够得到较准确的计算结果。     

太阳能海水淡化新技术综述

依据太阳能的光效应和热效应对传统的海水淡化进行分类,列举了太阳能与传统蒸馏法与渗析法的结合形式,指出了传统蒸馏法效率不高的原因,重点介绍利用冷凝潜热和提升换热效率的新型高效海水淡化技术以及反渗透的能量回收装置,认为将太阳能与传统海水淡化技术有机结合起来前景广阔,并简述了太阳能收集器的研究现状及先进技术,为太阳能海水淡化技术的进一步研究和发展提供了参考与依据.     

Recovery of volatile compounds from butter oil

Three methods for the isolation of volatile compounds from oils and fats were compared using small concentrations (approximately 1 ppm) of added C_3-12 n-alkan-2-ones and C_2-10 n-alkan-1-ols in commercial butter oil. These were : high vacuum degassing, cold-finger molecular distillation and reduced pressure steam distillation. Several modifications were incorporated. The highest yields of all compounds were obtained by cold-finger molecular distillation but difficulties were encountered in subsequent analysis. It was more convenient to recover compounds boiling below 150C by either high vacuum degassing or reduced pressure steam distillation. The latter was more efficient for the higher boiling compounds. Extraction with organic solvents was not required in any of these techniques. The combination of high vacuum degassing and cold-finger molecular distillation was found to be the best method of analyzing the complete range of model compounds.     

The second law optimal state of a diabatic binary tray distillation column

A new numerical procedure to minimize the entropy production in diabatic tray distillation columns has been developed. The method was based on a least square regression of the entropy production at each tray. A diabatic column is a column with heat exchangers on all trays. The method was demonstrated on a distillation column separating propylene from propane. The entropy production included contributions from the heat transfer in the heat exchangers and the mass and heat transfer between liquid and vapor inside the distillation column. It was minimized for a number of binary tray distillation columns with fixed heat transfer area, number of trays, and feed stream temperature and composition. For the first time, the areas of heat exchange were used as variables in the optimization. An analytical result is that the entropy production due to heat transfer is proportional to the area of each heat exchanger in the optimal state. For many distillation columns, this is equivalent to a constant driving force for heat transfer. The entropy production was reduced with up to 30% in the cases with large heat transfer area and many trays. In large process facilities, this reduction would ideally lead to 1-2 GWh of saved exergy per year. The most important variable in obtaining these reductions is the total heat transfer area. The investigation was done with a perspective to later include the column as a part in an optimization of a larger process. We found that the entropy production of the column behaved almost as a quadratic function when the composition of the feed stream changed. This means that the feed composition is a natural, easy variable for a second law optimization when the distillation column is a part of a process. The entropy production was insensitive to variations in the feed temperature.     

Effect of the condensing cover''s slope on internal heat and mass transfer in distillation: an indoor simulation

The objective of the study was to determine a relation for predicting convective and evaporative heat transfer coefficients for all three condensing surfaces inclined at 15°, 30° and 45° under indoor simulation. The condensing covers were made of the same flat transparent glass as found in any solar distillation unit. The operating temperature range for the experiment was maintained at steady state from 40°C to 80°C by using a constant temperature bath. The temperatures and yields obtained for a 10-min interval were used to determine the values of constants C and n and consequently convective and evaporative heat transfer coefficients. It was found that a higher yield was obtained with an increase in temperature for a 30° slope compared to 15° and 45° slopes of the condensing cover.     

SIMULTANEOUS HEAT AND FLUID FLOW IN POROUS MEDIA: CASE STUDY: STEAM INJECTION FOR TERTIARY OIL RECOVERY

Heat transfer and fluid flow in porous media occur simultaneously in thermal enhanced oil recovery and significantly increase the rate of energy transfer. The purpose of this investigation was to take advantage of such contemporary transfers and to study heavy oil recovery efficiency using hot-water flooding, cold-water flooding, and steam injection into porous media. A set of multistage laboratory tests was performed to find the temperature profile during steam injection as a means of tertiary oil recovery. Sand-packed models were utilized to investigate the oil recovery efficiency during cold and hot water injection as well as steam flooding for both secondary and tertiary oil production stages. An oil bank was formed in steam injection during the tertiary oil recovery from a vertical standing sand-packed model, resulting in very high oil recovery efficiency. Steam injection was found to be very effective, compared to cold- and hot-water flooding, for the recovery of heavy oil. Based on the principles of transport phenomena in porous media, a mathematical model was developed to predict the temperature profile during the steam injection process. Satisfactory agreement is achieved between the temperature profile predicted from the model and the experimental results.     

SIMULTANEOUS HEAT AND FLUID FLOW IN POROUS MEDIA: CASE STUDY: STEAM INJECTION FOR TERTIARY OIL RECOVERY

Heat transfer and fluid flow in porous media occur simultaneously in thermal enhanced oil recovery and significantly increase the rate of energy transfer. The purpose of this investigation was to take advantage of such contemporary transfers and to study heavy oil recovery efficiency using hot-water flooding, cold-water flooding, and steam injection into porous media. A set of multistage laboratory tests was performed to find the temperature profile during steam injection as a means of tertiary oil recovery. Sand-packed models were utilized to investigate the oil recovery efficiency during cold and hot water injection as well as steam flooding for both secondary and tertiary oil production stages. An oil bank was formed in steam injection during the tertiary oil recovery from a vertical standing sand-packed model, resulting in very high oil recovery efficiency. Steam injection was found to be very effective, compared to cold- and hot-water flooding, for the recovery of heavy oil. Based on the principles of transport phenomena in porous media, a mathematical model was developed to predict the temperature profile during the steam injection process. Satisfactory agreement is achieved between the temperature profile predicted from the model and the experimental results.     

Operational optimization of crude oil distillation systems using artificial neural networks

A new methodology for optimizing heat-integrated crude oil distillation systems is proposed in this work. The new procedure considers an artificial neural networks (ANN) model for representing the distillation column. Models of the distillation column and the associated existing heat exchanger network are incorporated in an optimization framework to systematically determine the operating conditions that improve the overall process economics. Of particular interest is the problem of optimizing the net value of the products obtained from the column by increasing the yield of higher-value products at the expense of less valuable products, while taking into account feasibility of the distillation specifications, heat recovery, energy and equipment constraints. A two-stage procedure is applied to first optimize the column operating conditions based on minimum utility requirements. In the second stage the heat exchanger network is designed.     

氯乙烯生产过程的节能

用ASPEN PLUS 软件对某氯乙烯装置进行了严格的数学模拟,并进行了全过程的节能研究。通过减小VC1#塔的回流比,节省了高压蒸汽;通过提高EDC2#塔压,获得了高品位的热源,分别为EDC1#塔、脱水塔、EDC回收塔及HCl塔的再沸器供热,并为EDC2#塔的进料预热。提出的方案可节省低压蒸汽11 450.75 kg/h,中压蒸汽4738.07 kg/h,高压蒸汽6153.51 kg/h,冷却水11 746 343.9 kg/h,年节省费用为2566.0万元。     

卡宾达原油常减压蒸馏装置负荷转移技术的模拟与分析

用ASPENPLUS软件对卡宾达原油常减压蒸馏装置进行了流程模拟计算,通过标定值和计算值的比较,验证了所建模型的可靠性,并通过分析找出负荷转移技术操作的关键因素。在此基础上对加工同种原油不同加工量操作条件进行优化与分析。     

厚朴叶挥发油的化学成分及对植物病原真菌的抑菌活性研究

用水蒸汽蒸馏法提取厚朴树叶挥发油、采用GC-MS联用技术分析了其挥发油的化学成分,并用生长速率法检测了对五种植物病原真菌的抑菌活性。结果表明,从挥发油中分离鉴定出40种化合物。厚朴树叶挥发油对油菜菌核病菌具有选择性的抑菌活性,在500 ppm抑制率为81.63%。     

从抽余油中分离甲基环戊烷

研究了从芳烃抽余油中分离甲基环戊烷的方法和流程,首先用Aspen Plus软件模拟了精馏法提取甲基环戊烷的分离结果。通过模拟计算得到了最优的设计参数、操作条件、各塔冷凝器、再沸器的热负荷。在此基础上,还模拟了用甲醇作共沸剂共沸精馏分离得到甲基环戊烷的结果,获得了最优的设计参数和操作条件。     

筛型塔板在喷射及混合状态操作下三相传质性能

以空气-水-油(煤油及白油)为介质在600mm×150mm矩形冷模塔内测试了筛型塔板气液液三相传质性能。研究喷射及混合状态下,气速、液流强度、油水比等操作条件和塔板结构参数(孔径、开孔率)对塔板效率的影响。气膜和液膜控制的2种物系的实验表明,三相传质的板效率在喷射状态下明显高于混合状态。对测试数据进行关联,获得适用于喷射及混合状态下三相传质板效率的估算式。     

反应精馏过程中的场协同分析

应用唯象理论，分析了反应精馏过程中各种场(如温度场、浓度场、化学势场等)之间的协同关系，以及同一场内不同分量之间的协同关系。提出了在多场协同条件下质量通量和热量通量的唯象表达式以及相应的传质和传热系数。从而揭示了该过程中传质、传热以及化学反应之间的相互影响规律，为强化该过程提供了理论依据。     

高黏介质中内插扭带对换热管换热性能影响

某石化公司炼油厂第二套常减压装置中换热器的热交换介质为高黏度的原油及其附属产品,在对流换热过程中传热系数低,动能消耗大。针对这一现状,本文设计了一种换热管内插间歇半扭带,利用计算流体力学软件Fluent对内插间歇半扭带换热管在实际工况下的换热过程进行数值模拟,与光滑管、内插连续扭带换热管进行了对比,并给出了间歇半扭带传热元件的优化设计参数。结果表明:内插间歇半扭带大幅提高了换热管内流体的努塞尔数Nu,同时也使换热管内摩擦阻力系数f增大;间歇半扭带换热管的换热效率η比内插连续扭带换热管提高8%~12%;当间歇半扭带的扭曲率y为10、连接杆长度s为345mm时,换热效率η最高,达到2.06。研究结果为该常减压装置换热器强化传热的研究提供了理论依据。     

Heat transfer to an immiscible liquid mixture and between liquids in direct contact

Heat transfer to a mixture of two immiscible liquids has been studied in connection with the development of a process for the desalination of sea water. The liquid system consisted of water and refined mineral oil, produced by BP under the trade name of Energol WM-2.Heat transfer to water drops descending through the mineral oil was also investigated. The drag coefficients of the drops in motion were expressed as a function of the Reynolds number. A good correlation was obtained for the heat transfer coefficient expressing the Nusselt number in terms of the Peclet number.Heat transfer to a mixture of two immiscible liquids in co-current turbulent flow without phase change was extensively studied. Friction factor and heat transfer for the oil-in-water type mixtures were theoretically expressed in terms of the volume fraction of oil. The experimental data checked the theoretical derivation quite satisfactorily. No correlations could be obtained for the water-in-oil systems.Similar studies were made for heat transfer in the laminar and turbulent flow with phase change, using a pilot-plant evaporator. Curves were obtained relating the convective heat transfer coefficient to fluid velocity for the liquid mixtures. It was established that, the heat transfer coefficient in evaporation decreased by velocity in the laminar region, but increased in the turbulent region.     

常减压蒸馏换热网络节能优化

利用夹点技术对常减压蒸馏换热网络进行分析,优化该常减压蒸馏装置换热网络结构,最大限度的回收热量,节能效果显著。     

3~#常减压蒸馏装置换热网络的操作优化

利用英国Process Integration Ltd.(PIL)公司最新的原油精馏系统优化技术,对茂名分公司3#常减压蒸馏装置换热网络进行建模及优化操作。结果表明,通过优化常压塔中段取热分配,将常顶冷回流量降到几乎为零,原油换热后温度提高了7℃,实现了能量回收最大化。