冷凝法油气回收技术与应用

油品在储运和销售过程中部分轻烃组分挥发进入大气,造成资源浪费和环境危害.油气回收既可实现油气污染治理又能产生可观的经济效益.结合中国油气储运和销售环节的现状以及相关技术的发展,对几种油气回收的方法进行了对比分析,认为采用多元工质复叠(或自复叠)制冷技术的冷凝法具有较好的经济性和可靠性.介绍了自主研发的冷凝式油气回收设备...     

A computational analysis of multidimensional piecewise-linear models with applications to oil production optimization

Production optimization of gas-lifted oil wells under facility, routing and pressure constraints is a challenging problem, which has attracted the interest of operations engineers aiming to drive economic gains and scientists for its inherent complexity. The hardness of this problem rests on the non-linear characteristics of the multidimensional well-production and pressure-drop functions, as well as the discrete routing decisions. To this end, this work develops several formulations in Mixed-Integer Linear Programming (MILP) using multidimensional piecewise-linear models to approximate the non-linear functions with domains spliced in hypercubes and simplexes. Computational and simulation analyses were performed considering a synthetic but realistic oil field modeled with a multiphase-flow simulator. The purpose of the analyses was to assess the relative performance of the MILP formulations and their impact on the simulated oil production.     

Improvement of water and oil repellency on wood substrates by using fluorinated silica nanocoating

We have investigated a one-step fabrication of fluoro-containing silica coating on wooden substrates, showing multi-functions including super repellency toward water and sunflower oil, low sliding angles, good durability, and low adsorption capacity of moisture. The repellent slurry, consisting of well-mixing silica nanospheres and perfluoroalkyl methacrylic copolymer, is simply prepared and subsequently sprayed over wooden substrates with good adhesion. It has shown that the decoration of silica nanospheres on microscaled wooden texture acts as a crucial role in improving the repellency toward water and sunflower oil droplets. The maximal contact angles can reach as high as 168.3° and 153.6° for water and sunflower oil drops, respectively. These analyses of wetted fraction and work of adhesion also demonstrate the improved repellency due to the addition of silica. This improvement of the repellencies is ascribed to the fact that the drops partially sit on F-coated silica spheres, leaving a layer of air underneath the droplet (i.e., Cassie state). On the basis of the results, the multi-functional coating on wooden substrates delivers a promising commercial feasibility on a variety of woodworks.     

X射线荧光光谱法直接测定油页岩中微量元素

本文提出用微晶纤维素与GSD等国家一级系列标样按不同比例混合制备标准样品。油页岩样品不经前处理,直接粉末法压片,经验系数法校正元素间效应,直接测定油页岩中V、Co、Ni、Cr、Cu、Zn、Sr、Ba和Rb等元素的X射线荧光光谱法。样品分析结果与ICP-AES法分析结果基本一致,本法具有简单、准确、实用的特点。     

Analysis of capillary interaction and oil recovery under ultrasonic waves

Although, the effects of ultrasonic irradiation on multiphase flow through porous media have been studied in the past few decades, the physics of the acoustic interaction between fluid and rock is not yet well understood. Various mechanisms may be responsible for enhancing the flow of oil through porous media in the presence of an acoustic field. Capillary related mechanisms are peristaltic transport due to mechanical deformation of the pore walls, reduction of capillary forces due to the destruction of surface films generated across pore boundaries, coalescence of oil drops due to Bjerknes forces, oscillation and excitation of capillary trapped oil drops, forces generated by cavitating bubbles, and sonocapillary effects. Insight into the physical principles governing the mobilization of oil by ultrasonic waves is vital for developing and implementing novel techniques of oil extraction. This paper aims at identifying and analyzing the influence of high-frequency, high-intensity ultrasonic radiation on capillary imbibition. Laboratory experiments were performed using cylindrical Berea sandstone and Indiana limestone samples with all sides (quasi-co-current imbibition), and only one side (counter-current imbibition) contacting with the aqueous phase. The oil saturated cores were placed in an ultrasonic bath, and brought into contact with the aqueous phase. The recovery rate due to capillary imbibition was monitored against time. Air–water, mineral oil–brine, mineral oil–surfactant solution and mineral oil-polymer solution experiments were run each exploring a separate physical process governing acoustic stimulation. Water–air imbibition tests isolate the effect of ultrasound on wettability, capillarity and density, while oil–brine imbibition experiments help outline the ultrasonic effect on viscosity and interfacial interaction between oil, rock and aqueous phase. We find that ultrasonic irradiation enhances capillary imbibition recovery of oil for various fluid pairs, and that such process is dependent on the interfacial tension and density of the fluids. Although more evidence is needed, some runs hint that wettability was not altered substantially under ultrasound. Preliminary analysis of the imbibition recoveries also suggests that ultrasound enhances surfactant solubility and reduce surfactant adsorption onto the rock matrix. Additionally, counter-current experiments involving kerosene and brine in epoxy coated Berea sandstone showed a dramatic decline in recovery. Therefore, the effectiveness of any ultrasonic application may strongly depend on the nature of interaction type, i.e., co- or counter-current flow. A modified form of an exponential model was employed to fit the recovery curves in an attempt to quantify the factors causing the incremental recovery by ultrasonic waves for different fluid pairs and rock types.     

阴离子型聚丙烯酰胺与阳离子表面活性剂的相互作用

采用自由基水溶液共聚法制备了带有负电荷的水溶性聚丙烯酰胺,研究了水溶液中聚合物与阳离子表面活性剂的相互作用及所导致的水溶性、黏度和流变学性质的变化,为进一步研究驱油提供了理论基础.     

相选择性凝胶因子及其在油品污染处理中的应用研究进展

近年来含油污水及海上油品泄漏问题日益严重,威胁着人类的生存环境和海洋生态环境。相选择性凝胶因子因其制备简单、生物相容性好、快速高效、可重复利用等优点为油品污染处理提供了新选择。本文首先介绍了相选择性凝胶因子的分类和自组装机理及相选择性凝胶因子的发展现状,重点对小分子凝胶因子进行了阐述,其中小分子凝胶因子包括氨基酸类、有机酸及其盐类、胆固醇类和糖类衍生物类等,并对有机高分子凝胶因子做了简单介绍;最后对相选择性凝胶因子的发展做出了展望。     

A free boundary problem arising in oil production

For a stable two-phase free boundary problem arising in oil production, we prove the existence of a weak solution and the continuity of the free boundary.

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Sommario Si prova un teorema di esistenza di una soluzione debole per un problema stazionario a contorno libero a due fasi che interessa la produzione di petrolio. Si dimostra inoltre la continuità del contorno libero.

     

An adaptive network based fuzzy inference system–auto regression–analysis of variance algorithm for improvement of oil consumption estimation and policy making: The cases of Canada,United Kingdom,and South Korea

This paper presents an adaptive network based fuzzy inference system (ANFIS)–auto regression (AR)–analysis of variance (ANOVA) algorithm to improve oil consumption estimation and policy making. ANFIS algorithm is developed by different data preprocessing methods and the efficiency of ANFIS is examined against auto regression (AR) in Canada, United Kingdom and South Korea. For this purpose, mean absolute percentage error (MAPE) is used to show the efficiency of ANFIS. The algorithm for calculating ANFIS performance is based on its closed and open simulation abilities. Moreover, it is concluded that ANFIS provides better results than AR in Canada, United Kingdom and South Korea. This is unlike previous expectations that auto regression always provides better estimation for oil consumption estimation. In addition, ANOVA is used to identify policy making strategies with respect to oil consumption. This is the first study that introduces an integrated ANFIS–AR–ANOVA algorithm with preprocessing and post processing modules for improvement of oil consumption estimation in industrialized countries.     

一种基于荧光信号的海面厚油膜评估方法

油膜厚度是海面溢油污染评估分析的一个重要指标,激光诱导荧光(LIF)技术是目前最有效的海面溢油探测技术之一,基于LIF探测技术的油膜厚度反演算法当下仅有适用于薄油膜(≤10~20 μm)的评估方法,而对于较厚油膜(>20 μm)的评估目前尚无有效的反演算法。鉴于此,提出一种基于LIF技术适用于较厚油膜的反演算法,该算法采用油膜荧光信号反演油膜厚度,推导了油膜厚度反演公式,并给出了基于该反演算法的油膜厚度评估方法。首先采用最大类间方差算法(Otsu)选取合适的荧光光谱波段,然后根据选取波段内每个波长的光谱数据反演油膜厚度,最后采用反演油膜厚度的平均值作为油膜厚度评估结果。研究了该算法的适用范围,给出了该算法有效评估范围最大值与测量相对误差的关系,并结合消光系数给出了在多种测量误差条件下不同消光系数油品有效评估范围的最大值。通过实验对本文方法进行了验证,选用原油和白油的混合油(1∶50)作为实验油品,以波长为405 nm的激光作为激发光源,采集波长范围为420～750 nm,采集了海水背景荧光和拉曼散射光光谱、实验油品的荧光特征光谱和多种不同厚度的较厚油膜的荧光光谱。采用Otsu算法选取420～476 nm波段评估油膜厚度,在实验油品油膜厚度≤800 μm时,该算法对油膜厚度的评估具有较高的精度,平均误差为10.5%;在油膜厚度>800 μm时,平均误差为28.8%,评估误差较大且随油膜厚度的增加快速变大,该实验结果与利用测量相对误差和消光系数的分析结果一致。实验结果表明,该方法可以实现对海面较厚油膜厚度的有效评估,并可以根据测量相对误差和消光系数判断评估结果的有效性。