油溶性减阻剂的研究进展

油溶性减阻剂是一种用于油品输送的化学添加剂,可减小油品在管道中的阻力,起到节能作用。文章介绍了油溶性减阻剂的合成,重点介绍油溶性减阻剂后处理的条件、步骤,和减阻剂的几种不同后处理方法。最后介绍了减阻效果的影响因素,并简介了减阻剂的减阻机理。     

输油管道减阻率影响因素及预测模型概述

减阻剂对输油管道减阻增输具有重要意义。概述了现有的油品减阻机理假说,从减阻聚合物的物性、油流规律、管线的几何尺寸以及操作运行状态等方面详细介绍了对输油管道减阻率的影响。总结了三种常见的减阻率预测模型,并说明了各自的适用性,对在输油管道上应用减阻剂具有参考价值。     

输油管道用聚α-烯烃类减阻剂的研究进展

聚α-烯烃类减阻剂是一种广泛用于输油管道中的化学添加剂,属于油溶性减阻剂,只需要添加很少的量(一般以ppm计量),就可以有效减小油品在管道中的阻力,达到减阻增输的作用,从而显著提高了经济效益。文章中主要对于近年来聚α-烯烃类减阻剂的减阻机理、制备工艺(主要包括聚合方式和后处理方式)、以及主要的专利制备技术的研究进展进行了介绍,并对其在未来的发展前景进行了预测。     

聚α-烯烃油品减阻剂减阻性能研究

以1-癸烯为聚合单体,在Ziegler-Natta催化剂TiCl3/AlR2Cl上进行α-烯烃催化聚合研究,考察了主催化剂和助催化剂用量、聚合反应温度及聚合物相对分子质量对聚α-烯烃油品减阻剂减阻性能的影响,确定最佳减阻聚合工艺条件为V(1-癸烯)∶m(TiCl3)∶V(AlR2Cl)=100 mL∶50 mg∶0.25 mL,聚合反应温度为265 K,在该条件下减阻率为45.3%,为高性能减阻剂的工业化开发提供参考。     

DR-1减阻剂相对减阻率影响因素分析

减阻剂对页岩气、煤层气和致密气等非常规油气资源的开发具有重要的意义,其在滑溜水压裂液体系中主要通过降低摩阻起到降低能耗、增加排量的作用。在现场使用中,配液用水的无机金属离子含量、减阻剂浓度和温度等因素会影响减阻剂的性能。本文考察了无机金属离子、减阻剂浓度和温度等因素对减阻剂减阻效果的影响。结果表明:温度升高导致DR-1粘度降低,进而减阻率也逐渐降低,温度高于60℃时,DR-1减阻率损失率达20%以上;无机金属离子尤其是Ca2+、Mg2+对减阻剂减阻性能影响较大,当水中Ca2+、Mg2+为800mg/L时,DR-1减阻率损失率达20%以上。     

页岩储层压裂用减阻剂的研究及应用进展

介绍了聚合物型、表面活性剂型、生物基多糖型以及纳米复合型减阻剂的研究进展;简述了减阻剂产品的现场应用情况,分析了减阻剂的相对分子质量及其分布、分子结构以及离子特征对减阻性能的影响;探讨了其减阻机理及规律;阐述了减阻剂产品的优缺点及循环再利用的必要性;指出了压裂用减阻剂未来的发展方向和趋势:认为稳定性好,减阻效率高,抗盐抗污染能力强,能够满足现场施工要求的纳米复合减阻剂将是未来研究的重点。同时,提出提高压裂液返排率,增加循环利用率,保持储层裂缝有较好的导流能力也将成为减阻剂的热门研究领域。     

大落差成品油管道投产过程中油品乳化问题研究

随着全国经济的发展,西南、西部等地势复杂地区的成品油管道陆续建成。在对成品油管道常见的投产方式进行简要介绍的基础上,针对大落差成品油管道投产过程中极易发生投油质量事故的问题,主要探讨了初始混油、油水界面流速、高点后不满流、非计划停输、柴油添加剂、管输减阻剂及管道内存气、水、机杂、微生物对大落差成品油管道投产油品乳化的影响。最后以西部某大落差成品油管道为例,对其投产过程中油品乳化原因进行深刻剖析,并提出了几点有利于大落差管道顺利投产的建议,为科学制定大落差成品油管道投产方案提供参考。     

溶剂对聚合物减阻剂流变行为和减阻性能的影响

采用博力飞旋转粘度计测定了减阻剂在不同溶剂中溶液的流变性能,通过减阻剂室内模拟环道评价装置测定了不同溶剂合成的聚合物的减阻率。结果表明,减阻剂属于典型的剪切增稠型非牛顿流体;减阻剂在不同溶剂中溶液的粘度随着温度升高而降低;当环己烷与减阻剂的溶度参数相等时,减阻剂在环己烷中的溶解性能最好。并探讨了剪切增稠流体的减阻机理,分析了不同溶剂合成的减阻剂对减阻性能的影响。     

高分子量乳液型减阻剂的合成及评价

采用反相乳液聚合方法制备了一种用于滑溜水压裂液的高分子量乳液型减阻剂。考察了复合乳化剂对乳液减阻剂稳定性的影响,研究了乳化剂含量、聚合温度和引发剂浓度对减阻剂分子量的影响,分析了减阻剂的分子结构、乳液粒径大小分布和减阻效率。实验结果表明:m(Span80)∶m(Tween80)∶m(OP-10)=20∶2∶1时乳液最为稳定;在18℃、乳化剂在油相中质量分数为15%、引发剂质量为单体质量的0.015%时,得到分子量达1.8×107g/mol的稳定乳液型减阻剂。在清水中加入0.05%的减阻剂,减阻率高达62.8%。     

湍流减阻剂聚α-烯烃的流变性能实验研究

针对成品油长输管道中聚合物减阻剂流动性能差、注入系统容易堵塞等问题，采用旋转流变仪、电子显微镜和动态光散射系统，从微观和宏观角度分析了悬浮颗粒尺寸形态、温度和剪切速率对3种不同组分的直链聚α-烯烃油溶性减阻剂流变性能的影响。实验结果表明：在-4—40℃温度区间内，FLOMX减阻剂悬浮颗粒直径为100—200μm,紧密均匀排列，相互作用力较强，在剪切速率分别为5,10,50,100 s^-1的条件下，黏度变化率分别对应为262.2%,251.3%,216.1%,230.2%;减阻剂СНИТРЕН4110和СНИТРЕН2110的悬浮颗粒直径小，且黏度变化率较小，即减阻剂悬浮颗粒尺寸与其黏温性能呈负相关。基于以上研究结果，可知聚合物减阻剂最佳注入温度区间为25—40℃,且注入时应提高剪切速率(>30 s^-1),以此提高成品油管道湍流减阻剂的注入效率。     

天然气减阻剂减阻机理探讨

对现有天然气减阻剂减阻机理进行了较深入的分析,重点介绍了光滑减阻、粘弹减阻和光滑一粘弹减阻机理。从微观结构分析了输气管道近壁区阻力的成因,进一步证实了输气管道近壁区是实现湍流控制和减阻增输的关键区域;从实验研究和理论研究两方面对各个减阻机理进行了评述,并列举了各减阻机理的理论依据或事实依据。此外,简要介绍了天然气减阻剂的应用条件,并提出了减阻机理的研究重点。     

Using water-miscible nonionic hydrophobic monomer associating HPAM as drag reducing agent

A water-miscible nonionic surfmer (AC-TX100) was synthesized based on Triton X-100 and acryloyl chloride. Then, a terpolymer P(AM/AA/AC-TX100) was synthesized by free radical polymerization in aqueous solution and intended to be used as drag reducing agent (DRA). The DRA was defined to be P(AM_87.32/AA_12.46/AC-TX100_0.22) according to ¹H NMR and elemental analysis, the molecular weight was 2.12 × 10⁶ g/mol according to scattering method. DRA shows excellent performance in drag reduction (DR). The highest DR rate of 76% can be obtained when DRA concentration is 0.023% in fresh water; while in brine containing 3% NaCl, DR rate decreases, and it is necessary to increase the concentration to 0.05% to ensure that DR rate is higher than 70%. SEM and cryo-TEM show that DRA forms a network structure in aqueous solution, and the tightness of this structure has a direct influence on DR performance. Specifically, DRA molecules stretch into the whirlpools generated by water at high flow rates, reducing the quantity and intensity of whirlpools, thereby lowering the energy loss and the friction. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48362.     

Drag reduction in co-current down flow packed column using xanthan gum

Drag reduction is one of the most important techniques for reducing energy consumption in a packed bed contactor. The present work involves an experimental investigation on flow regime transition for air-water system with and without drag reducing agent (DRA), two-phase pressure drop, friction factor and drag reduction using xanthan gum as DRA. Drag reduction was quantified from the two-phase pressure drop data. Based on the present observations it was found that the percentage drag reduction increases with an increase in the concentration of DRA and it is only effective in the range of 300 ppm to 800 ppm. The experimental results indicate that a maximum of 80% drag reduction was achievable using xanthan gum (800 ppm) as DRA. Furthermore, the experimental data were validated with the available literature correlations.     

EP减阻剂在输油管道中的应用

为了有效解决中俄原油管道投产以来满负荷运行问题,满足输量与压力的运行要求,进行了添加EP系列减阻剂现场试验,本次试验对漠河至加格达奇这段管道进行实验研究,试验结果表明:在10×10~(-6)加剂浓度下,漠大线输量可以由2 100 m~3/h增加到2 400 m~3/h,增输率可以达到14.29%,减阻率可以达到21%。添加EP系列减阻剂可以解决漠大线运行瓶颈问题。     

溶液聚合制备油溶性减阻剂中溶剂的选择和聚合产物性能的表征

依据溶度参数理论预测溶剂和聚合物的相容性,为合成具有更高分子量的减阻聚合物提供理论指导。实验结果表明,使用脂肪烃溶剂（正己烷、正辛烷和环己烷）和芳香烃溶剂（甲苯、苯和氯苯）合成减阻剂黏均分子量的大小顺序与依据溶度参数理论预测不同溶剂合成减阻剂的分子量大小顺序吻合。脂肪烃溶剂是α-烯烃聚合的良溶剂,芳香烃溶剂是α-烯烃聚合的不良溶剂。良溶剂中环己烷是α-烯烃聚合的最佳溶剂,易合成分子量较大的减阻剂。同时,通过室内环道评价装置及XRD和1H-NMR测试手段对聚合产物的结构和性能进行了表征。     

纳米流体对空气与水通过水平管道迟缓两相流的减阻作用的实验研究（英文）

This study investigates the effect of injecting nanofluids containing nano-SiO2 as drag reducing agents (DRA) at different concentrations on the pressure drop of air–water flow through horizontal pipe. The test fluid used in this study was air–water with nano-SiO2 particles at 0.1%–1%mass concentration. The test sections of the experi-mental set-up were five pipes of the same length of 9 m with ID from 0.0127m–0.03175m (0.5 to 1.25 in). Air–water flow was run in slug flow regime under different volumetric flow rates. The results of drag reduction (η%) indicated that the addition of DRA could be efficient up to some dosage. Drag reduction performed much better for smal er pipe diameters than it did for larger ones. For various nanosilica concentrations, the maximum drag reduction was about 66.8%for 0.75%mass concentration of nanosilica.     

Experimental study of drag reduction by a polymeric additive in slug two-phase flow of crude oil and air in horizontal pipes

In this study the effect of the presence of a drag reducing agent (DRA) on the pressure drop in cocurrent horizontal pipes carrying slug two-phase flow of air and crude oil is investigated. An experimental set-up is erected. The test section of the experimental set-up is consisted of: a smooth pipe of polycarbonate with 10.3 m long and 2.54 cm ID, a rough pipe of galvanized iron with 8.8 m long and 2.54 cm ID and a rough pipe of galvanized iron with 8.8 m long and 1.27 cm ID. The employing DRA is a Polyalpha-olefin (Polyisobutylene). The percent drag reduction (%DR) is calculated using the obtained experimental data, in presence of the DRA. The results show that addition of DRA could be effective up to some doses of DRA after which the pressure drop is kept constant. A %DR of about 40 is obtained for some experimental conditions.     

表面活性剂添加对歧管式微通道阻力特性的影响

歧管式微通道（MMC）热沉具有热阻小、结构紧凑、冷却液流量小、流速低、沿着流动方向温度分布均匀等优点,但其小尺寸所产生的较大压降却增加了泵功的损耗.本文研究了表面活性剂添加对其阻力特性的影响,实验选用了纯度为95%的阴离子表面活性剂十二烷基硫酸钠（SDS）和纯度为98%的新型绿色非离子表面活性剂烷基多糖苷（APG）作为减阻添加剂,浓度分别为100和300 mg·kg^-1,结果表明阻力减小率与流速和温度有关.在层流区内减阻效果不是特别明显;但是当流体进入紊流区后阻力减小率开始明显增大,尤其是进入充分发展的紊流区后减阻效果大大加强.此外,温度的提升也可增加阻力减小率,但添加SDS后减阻效果的改善却不及APG.通过对两种不同类型表面活性剂的实验比较,发现温度较高时APG比SDS具有更佳的减阻效果.