發(fā)布時(shí)間：2018-04-05 10:21

  本文選題：復(fù)配體系　切入點(diǎn)：黏彈性　出處：《西南石油大學(xué)》2015年碩士論文

【摘要】：表面活性劑驅(qū)作為一種重要的提高采收率方法,其主要通過(guò)降低油水界面張力、改善巖石表面潤(rùn)濕性、形成微乳液等提高采收率。目前常規(guī)的表面活性劑控制流度能力差,聚表二元體系無(wú)法有效避免色譜分離現(xiàn)象,黏彈性表面活性劑(VES)彌補(bǔ)了其缺點(diǎn),既有增黏性、又能降低油水界面張力,使得驅(qū)油效率、波及系數(shù)增加。本文通過(guò)對(duì)以陰離子表面活性劑(AT)為主劑分別與陽(yáng)離子表面活性劑(CA)、兩性離子型表面活性劑(BET)進(jìn)行復(fù)配篩選,確定了VES04和VES05兩個(gè)體系,并以韋2、沙7區(qū)塊為背景,研究了濃度、礦化度、溫度等因素對(duì)其流變性、聚集特征、油水界面張力、長(zhǎng)期穩(wěn)定性及乳化性能的影響。 根據(jù)篩選原則,VES04.VES05溶液分別以3：7、27：73的比例復(fù)配時(shí)體系性能優(yōu)良,正交實(shí)驗(yàn)表明濃度、溫度分別對(duì)VES04.VES05溶液黏度影響最大,重復(fù)實(shí)驗(yàn)也己驗(yàn)證,65℃時(shí)黏度達(dá)到20mPa·s;剪切穩(wěn)定性研究中,兩種溶液均呈現(xiàn)剪切變稀現(xiàn)象,剪應(yīng)力不斷增加；黏彈性特征明顯,流體類型都是假塑性流體,松弛時(shí)間隨濃度的增加分別增加、減小。通過(guò)環(huán)境掃描電鏡發(fā)現(xiàn),VES04.VES05溶液鏈節(jié)之間相互交疊,有不規(guī)則的網(wǎng)狀結(jié)構(gòu)出現(xiàn),而加入無(wú)機(jī)鹽后觀察到,分子結(jié)構(gòu)破碎分布,規(guī)整度低；運(yùn)用吊片法確定了溶液的臨界膠束濃度(CMC),并計(jì)算了表面張力γCMC、降低表面張力效率pC20、飽和分子面積Amin和最大吸附量Γmax等表面性質(zhì)參數(shù)。動(dòng)態(tài)光散射研究表明,蒸餾水配置的VES04.VES05溶液的粒徑分別是237.14nm、96.7nm；模擬水配置的的VES04、VES05溶液的粒徑有所增加. 不同濃度的VES04.VES05溶液與韋2、沙7原油在油藏溫度下油水界面張力能達(dá)到10-2或10-3數(shù)量級(jí),表現(xiàn)出良好的降低界面張力的能力；長(zhǎng)期耐溫抗鹽穩(wěn)定性研究中,隨著老化時(shí)間的增加,不同濃度的VES04.VES05溶液黏度均先減小后基本不變,老化后黏度保留率都在65%以上,4000mg/L的VES04溶液、3000mg/L的VES05溶液的界面張力在老化90d后仍然在10-2數(shù)量級(jí),表現(xiàn)出良好的耐溫抗鹽長(zhǎng)期穩(wěn)定性；乳化性能研究中,VES04溶液在油水比為3：7、2：8、韋2與沙7兩種原油條件下,析水率均迅速增加,在濃度為4000mg/L時(shí),乳化速率、乳化穩(wěn)定性較高；VES05溶液在上述條件下,高濃度的溶液析水率較低、乳化速率高、穩(wěn)定性好；VES04.VES05溶液分別在礦化度為5000mg/L、20000mg/L時(shí)乳化穩(wěn)定性最好；VES04、VES05溶液分別在油水比1：1、3：7時(shí)乳化速率最大,在油水比為3：7時(shí)乳化穩(wěn)定性最好。 本論文的研究為韋2、沙7區(qū)塊進(jìn)行表面活性劑驅(qū)油提供了參考,對(duì)油田生產(chǎn)具有一定指導(dǎo)意義。
[Abstract]:Surfactant flooding is an important method to improve oil recovery, which can improve the wettability of rock surface by reducing the interfacial tension of oil and water, forming microemulsion and so on.At present, the conventional surfactants have poor mobility control ability, the binary system can not effectively avoid the phenomenon of chromatographic separation, and the viscoelastic surfactant (VES) makes up for its shortcomings, which not only increases viscosity, but also reduces the oil-water interfacial tension, which makes the oil displacement efficiency.The sweep coefficient increases.In this paper, two systems of VES04 and VES05 were determined by the combination of anionic surfactant (ATT) and cationic surfactant (CAA) and amphoteric ionic surfactant (BET), and the concentration was studied with the background of block Wei 2 and block Sha 7.The effects of salinity, temperature and other factors on rheology, aggregation characteristics, oil-water interfacial tension, long-term stability and emulsification properties.According to the screening principle of VES04.VES05 solution, the properties of the system were excellent when the proportion of VES04.VES05 was 3: 727: 73. The orthogonal experiment showed that the concentration and temperature had the greatest influence on the viscosity of VES04.VES05 solution, and repeated experiments had also verified that the viscosity reached 20mPa s at 65 鈩，

本文編號(hào)：1714348