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为改进油井后期泵效低下、能耗高等缺陷,提出了一种基于PSO-ELM模型的潜油柱塞泵冲次优化方法.采用粒子群(PSO)算法与极限学习机(ELM)相结合的方式来实现动液面软测量建模;根据动液面及潜油柱塞泵工作电流变化,以油井运行经济性最优为目的建立目标函数得到潜油柱塞泵冲次,解决了在油井生产时不能准确调节抽油机冲次问题;最后以目标函数关系建立模糊控制器模型,根据输入参数调整潜油柱塞泵冲次.实验结果表明,建立的软测量模型预测动液面精度高,模糊控制器能够更加合理地调整抽油机冲次,最终达到智能调整冲次大小、提高油井采油率及节能的目的. 相似文献
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《International Journal of Hydrogen Energy》2019,44(11):5125-5136
This paper describes a numerical analysis of the melting process of gelled crude oil in water for hydrogen production. The melting characteristics of crude oil particles are analyzed, and the influence of flow velocity, particle radius, and hot water temperature on the melting process is discussed. The results indicate that the melting rate on the surface of the crude oil is different, the oil particles do not melt concentrically, and the monitoring points and rate of increase in temperature are not substantially affected by the phase change interval. The flow rate and particle radius are found to have a significant influence on the phase distribution of the oil droplets, but changes in water temperature have little effect. After validating a model of the melting process, we investigate the influence of oil particle size, water temperature, flow rate, and oil temperature. It is found that increases in water temperature and flow rate, or a decrease in oil particle size, tend to reduce the melting time. 相似文献
46.
Sevda Dehghani Ahad Hanifpour Mehdi Nekoomanesh-Haghighi Samahe Sadjadi Seyed Amin Mirmohammadi Ali Farhadi Naeimeh Bahri-Laleh 《应用聚合物科学杂志》2020,137(22):49018
The main aim of this research is to decrease the amount of AlCl3 content that is very corrosive and hazardous in the catalytic system, required for the α-olefin oligomerization without substantial change of final oil features. This was successfully achieved by supporting AlCl3 on different carriers. More precisely, a series of supported bimetallic catalysts was synthesized by immobilization of AlCl3 and TiCl4 onto Al2O3, SiO2, and mixed supports, that is, Al2O3/FeCl3 and SiO2/FeCl3. It was found that silica and alumina-based catalysts had higher catalytic activities compared to support free AlCl3; however, this enhancement for silica-based supports was more significant. According to gel permeation chromatography (GPC) results, the use of single supports, that is, Al2O3 and SiO2, increased oligomer's molecular weight, while the application of mixed supports resulted in the decrease of molecular weight of the oligomers. Viscosity characteristics of the synthesized oligomers have also been studied at two different temperatures of 40 and 100°C (KV40 and KV100). The viscosity index (VI) values, derived from KV40 and KV100, of the prepared oligomers were in the range of 126–145. The molecular weight and termination mechanisms of the oligomers were studied by 1H-NMR spectroscopy. The obtained results disclosed that the employed reaction conditions led to the production of oligomer chains with various structures including vinylidene (Vd), and di and three-substituted vinylene (2Vn, 3Vn) structures. 相似文献
47.
Florence Lacoste Patrick Carré Sylvie Dauguet Catarina Petisca Fernando Campos Daniel Ribera 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2020,37(9):1491-1502
ABSTRACT Processing Factors (PFs) reflect the concentration or dilution of pesticide residues resulting from food processing. PFs are key elements to demonstrate the compliance of processed foods with Maximum residue levels (MRLs) as set by Regulation 396/2005. While efforts have been made by the European Food Safety Authority (EFSA) and by national authorities to compile PFs from processing studies, such PFs are not available for all pesticides/processed product combinations. The EU vegetable oil and proteinmeal industry association (FEDIOL) has therefore developed a theoretical approach to approximate MRLs in crude vegetable oils and fats, based on the partition coefficient (log Pow) of the pesticides and on the oil content of the raw materials. To substantiate this approach, a pilot-scale processing study was initiated with rapeseeds spiked with selected pesticides and the experimental PFs for these pesticides determined. The aims of this study were (i) to study the reliability of pilot-scale conditions for PF determination and (ii) to assess the experimental PFs obtained in comparison to the theoretical PFs proposed by FEDIOL. This study demonstrated that production yields obtained for crude oil and meal in this processing study are similar to those in industrial processes even if differences were observed in the individual production steps (mechanical or solvent extraction steps). The experimental PFs obtained confirmed that the chosen fat-soluble pesticides did concentrate in the oil fraction. For metalaxyl-M having a log Pow lower than 3, a partitioning between the oil and the meal was observed, as expected. By comparing the experimental PFs and theoretical PFs, it can be concluded that the FEDIOL approach can be recommended as a suitable tool when PFs derived from specific processing studies are missing. Similar studies on pesticides with wider ranges of log Pow are required in order to complete our conclusions on default PFs for vegetable oils. 相似文献
48.
临涣选煤厂针对洗选过程中存在的精煤泥旋流器组溢流跑粗、精煤泥弧形筛筛下水跑粗、精煤泥弧形筛脱水效果较差等问题,重点开展精煤泥分级旋流器组入料分配不均匀、筛分错配物影响、弧形筛脱水效果的现场攻关和研究。现场大量试验表明:通过停止精煤泥旋流器组,增加精煤泥弧形筛数量、减小筛缝尺寸,改变精煤泥弧形筛击打,改用高频脱水筛等方式,从源头上解决了精煤泥分级旋流器组跑粗,明显改善了精煤泥弧形筛筛下水跑粗的问题,提高了精煤泥弧形筛分选效果。在降低介泥灰分、减少浮选过程中粗颗粒的含量、缓解浮选回收压力、降低降低浮选油耗、提高浮选精煤灰分、保证精煤产率、节约生产成本方面有实践意义。 相似文献
49.
Anna Stauff Julia Schnapka Frank Heckel Reinhard Matissek 《European Journal of Lipid Science and Technology》2020,122(7)
Mineral oil hydrocarbons (MOH) are present in many fats and oils as well as foods prepared thereof. A survey of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in different types of vegetable fats and oils is reported. Contents of MOSH/MOAH were quantified using liquid chromatography online‐coupled to gas chromatography with flame‐ionization detection (LC‐GC‐FID). Cocoa butter (n = 142) showed levels from <LOQ (2.5 mg kg?1) to 162 mg kg?1 ΣMOSH (sum of C10–C50) and <LOQ to 55 mg kg?1 ΣMOAH, in palm oil (n = 21) ΣMOSH were quantified from <LOQ to 124 mg kg?1 and ΣMOAH from <LOQ to 39 mg kg?1. Sunflower oil showed lower levels: ΣMOSH were determined in the range of <LOQ to 17 mg kg?1 and MOAH were not observed at all. A possible influence of deodorization and a subsequent minimization of MOSH/MOAH was investigated. Systematic model‐experiments were performed on laboratory scale using spiked cocoa butter. Significant minimization of volatile MOH subfractions ≤C24 were observed at a deodorization temperature of 210 °C. Deodorization can be considered as an important processing step to reduce or even remove volatile MOSH/MOAH ≤C24. Practical Applications: Regardless of their possible entry routes into the food chain, volatile fractions of MOSH/MOAH can be removed by deodorizing vegetable fats and oils. This model‐study identifies the temperatures of deodorization that provide a significant improvement toward minimization of undesired MOSH/MOAH. 相似文献
50.
研制一种适合对各种液压孔口或缝隙进行高低温流体力学试验的新型试验装置,运用该装置对具有不同几何参数的液压阻尼孔进行在-50~80℃宽温度范围内的流动特性试验,研究以普通抗磨液压油HM46和低温抗凝减振器油TITAN SAF 5045为工质及其温度变化时对液压阻尼孔流量-压力特性曲线、幂指数和流量系数的影响,研究表明,在低温条件下,液压阻尼孔的流量系数均因油液黏度增大、流动性变差而呈线性下降的趋势,从宏观上看,HM46通过液压阻尼孔时的流动稳定性较差,其对应流量系数的下降幅度明显大于TITAN SAF 5045对应的下降幅度,厚壁小孔流量系数的下降幅度明显大于薄壁小孔对应的下降幅度。研究所获得的新型试验装置、试验数据分析方法和具体理论公式为深入研究和优化现代液压元件在宽温度范围内的动态性能提供新型试验平台与理论基础。 相似文献