压裂液破胶效果对支撑剂回流影响的实验研究

川西浅层蓬莱镇组气藏地层温度低,容易出现压裂液破胶不彻底的情况,压后排液时常常导致支撑剂的回流返吐。研究压裂液破胶效果对支撑剂回流的影响规律,确定一个合适的破胶液粘度,对于压裂液配方优化调整具有重要的现实意义。文章对压裂液破胶效果与支撑剂回流返吐的影响关系作了详细的实验评价,证实破胶液粘度的临界点为10mPa.s,破胶液粘度低于10mPa.s时基本上不会对支撑剂回流产生影响。     

Thermophysical Properties of Low-Density Pure Alkanes and Their Binary Mixtures Calculated by Means of an (n-6) Lennard-Jones Temperature-Dependent Potential

Self-consistent calculations of interaction pVT-virial coefficients B ₁₂(T), viscosities η _mix (T), and diffusion coefficients D ₁₂(T) of binary mixtures of the alkanes C _n H_{2n + 2} (n < 6) are presented. This study is based on the recently developed model of the (n-6) Lennard-Jones temperature-dependent potential (LJTDP) and uses already obtained potential parameters of the pure alkanes as input data. The well-known and simple Lorentz-Berthelot (LB) and the more laborate Tang-Toennies (TT) mixing rules are applied to the potential parameters of the pure alkanes in order to determine those of the mixtures. The new Hohm–Zarkova–Damyanova (HZD) mixing rule, which is an extension of the TT-mixing rule, is also considered. The HZD takes into account that for the LJTDP model, in general, the repulsive parameter is an independent variable whose value n ≠ 12. As in a recent examination of binary mixtures of globular molecules, the LB-mixing rule is superior to TT- and HZD-mixing rules when calculating equilibrium properties such as B ₁₂(T). For the transport properties η _mix (T) and D ₁₂(T), the new mixing rule performs slightly better.Paper presented at the Seventeenth European Conference on Thermophysical Properties, September 5–8, 2005, Bratislava, Slovak Republic.     

不同油藏温度条件下HPAM水解度与黏度变化规律

实验测定了法国SNF公司的AN913(M-=1.72×107,HD=15.0%)、AN923(1.92×107,20.0%)、AN934(2.11×107,31.0%)3种聚合物在驱氧并化学稳定的浓度1.0 g/L的污水溶液中,在180小时热老化过程中水解度和溶液黏度(30℃)的变化。55℃老化的溶液用矿化度2.23 g/L、pH 9.0的下二门油田污水配制,70℃和80℃老化的溶液用矿化度5.33 g/L、pH 9.1的双河油田污水配制。水解度~老化曲线表明油藏条件下HPAM的水解是典型的自阻滞反应,初期水解快速,后期减慢,最终趋于稳定;初始水解度越低则水解越快;温度越高则水解越快且不同水解度聚合物的水解曲线越接近;55℃时的水解仍很明显。溶液黏度~老化时间曲线相似但有所不同:老化初期黏度增加快,达到最高值后维持稳定(55℃和80℃)或缓慢减小(70℃);达到最大黏度的老化时间,55℃下为100天,70℃下为60天,80℃下为30天;水解度越低则黏度增加越快;在70℃老化30天和在80℃老化5天后,AN913溶液的黏度超过AN923和AN934。以3种聚合物溶液黏度对水解度(15%~68%)作图,水解度达到~30%前黏度增大,以后大体稳定,水解度大于60%后略有下降;用HPAM水溶液结构和污水低钙镁含量(26,32 mg/L)解释这一结果。讨论了HPAM水解度对油藏的适应性:在55℃的下二门油藏及70℃和80℃的双河油藏,聚合物驱中分别使用水解度25%~30%、20%~25%、15%~20%的HPAM。图7表1参14。     

超声波对重油热反应的影响

探索了超声波对重油热反应的影响。讨论了超声波作用对重油的粘度、残炭和沥青质含量的影响，并探讨了其作用机理。结果表明，超声波作用大大增加了重油热反应的反应动力。随着超声波作用时间的增加，降粘率增大，残炭值升高，沥青质含量下降，表明油样发生了裂化和缩合反应。作用时间小于1h，油样性质变化较快；1h后变化较慢。超声波对不同油样的热反应影响效果不同。     

PTPCL的合成及其对ATH／UP填充体系的降粘作用

以十二醇和ε－己内酯为原料，钛酸四正丁酯为催化剂，合成了端羟基聚己内酯（ＨＴＴＰＣＬ）、１ｍｏｌＨＴＰＣＬ与０．５ｍｏｌＰ２Ｏ５反应后即生成端磷酸酯基 内酯（ＰＴＰＣＬ）的数均分子量为１５００时、生成的ＰＴＰＣＬ降粘效果最好，其最佳用量的ＡＴＨ １．２％。     

端氨基亚胺齐聚物改性BMI固化特征及粘度特性

采用旋转粘度仪和动态DSC技术分析研究了端氨基亚胺齐聚物改性BMI树脂的固化反应过程和粘度特性。其结果表明，树脂在130℃-195℃之间存在一个宽广的低粘度平台区；固化反应过程中的吸热和放热的共同作用使得固化反应仅有一个平缓的放热峰，固化反应为1．02级反应，反应活化能为107kJ/mol。     

Modeling Viscosity of Multicomponent Electrolyte Solutions

A comprehensive model for calculating the viscosity of aqueous electrolyte solutions has been developed. The model includes a long-range electrostatic interaction term, contributions of individual ions, and a contribution of specific interactions between ions or neutral species. The long-range electrostatic term is obtained from the Onsager–Fuoss theory, whereas the individual ionic contributions are calculated using the Jones–Dole B coefficients. A technique for predicting the temperature dependence of the B coefficients has been developed on the basis of the concept of structure-breaking and structure-making ions. The contribution of specific interactions between species, which is dominant for concentrated solutions, has been found to be a function of the ionic strength. The model reproduces the viscosity of aqueous systems ranging from dilute to concentrated solutions (up to ca. 30m) at temperatures up to 573 K with an accuracy that is appropriate for modeling industrially important systems. In particular, the viscosity of multicomponent systems can be accurately predicted using parameters obtained from single-solute systems.     

壳聚糖的酯化反应研究

讨论了壳聚糖乙酯／甲酯的制备以及反应温度、反应时间、反应试剂用量对酯化反应的影响。测定了产物的粘度、取代度、溶解性能。实验结果表明，反应产物的溶解性能随取代度的增加而提高。     

粘度测量的几种方法

文章介绍了粘度测量的过程毛细管技术以及几种直接或间接测量粘度的新方法。