西南石油大学学报(自然科学版) ›› 2017, Vol. 39 ›› Issue (5): 178-184.DOI: 10.11885/j.issn.16745086.2016.04.14.02

• 石油机械与油田化学 • 上一篇    

硫酸钡结垢动力学瞬态模型研究

李洪建1, 余先政1, 周文静2, 杨彬1   

  1. 1. 西南石油大学石油与天然气工程学院, 四川 成都 610500;
    2. 西南石油大学理学院, 四川 成都 610500
  • 收稿日期:2016-04-14 出版日期:2017-10-01 发布日期:2017-10-01
  • 作者简介:李洪建,1963年生,男,汉族,河南杞县人,副教授,主要从事油气田开发生产过程中的保护油气层技术与油田注水工艺技术研究。E-mail:lhj63@263.net;余先政,1992年生,男,汉族,河南淅川人,硕士研究生,主要从事油田注水过程中结垢机理与防垢技术方面的研究。E-mail:940061165@qq.com;周文静,1992年生,女,汉族,河南淅川人,硕士研究生,主要从事偏微分方程解法与图像处理方面的研究。E-mail:977830396@qq.com;杨彬,1991年生,男,汉族,四川自贡人,硕士研究生,主要从事油田注水过程中结垢机理与防垢技术方面的研究。E-mail:979864903@qq.com

Study on Transient Dynamic Model of Barium Sulfate Scale Formation

LI Hongjian1, YU Xianzheng1, ZHOU Wenjing2, YANG Bin1   

  1. 1. School of Oil & Natural Gas Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China;
    2. School of Sciences, Southwest Petroleum University, Chengdu, Sichuan 610500, China
  • Received:2016-04-14 Online:2017-10-01 Published:2017-10-01
  • Contact: 李洪建,E-mail:lhj63@263.net

摘要: 注水是维持地层压力及提高原油采收率的最主要开发方式。当注入水与地层水混合后,由于注入水中的SO42-与地层水中的Ba2+的化学不相容性,将产生BaSO4垢,堵塞储层的孔隙与喉道,造成严重的储层损害。为了定量预测硫酸钡结垢量,首先,在Bedrikovetsky经典动力学模型的基础上,详细推导了含扩散项的硫酸钡结垢动力学瞬态模型,对模型有限差分并利用第四和第五阶Runge-Kutta方程求出数值解,避免了国内外已有的模型求解过程中做出岩芯入口端Ba2+浓度与SO42-浓度比远小于1的假设,提高了模型的适用性。然后,通过岩芯瞬态驱替实验测定岩芯出口端Ba2+的浓度,利用浓度数据反演出模型中的两个重要系数——扩散系数和反应速率常数。最后,研究了低SO42-浓度的注入水驱替不同PV时岩芯中硫酸钡结垢量的分布。结果表明:随着驱替体积增加,岩芯内的硫酸钡结垢量增大;沿岩芯长度方向上的结垢量呈先增大后减小趋势;岩芯内最大结垢量的位置向岩芯中部偏移。

关键词: 硫酸钡结垢, 地层损害, 动力学模型, 有限差分

Abstract: When injected water is mixed with formation water, the chemical incompatibility between SO42- in the injected water and Ba2+ in the formation water produces BaSO4 scale, which clogs the pores and throat of the reservoir to cause serious damage to the reservoir. To quantitatively predict the amount of barium sulfate scale, we first used Bedrikovetsky classical dynamics model to deduce a detailed transient kinetic model of barium sulfate scale formation with diffusion term. Finite difference analysis was performed on the model, and the fourth and fifth order Runge-Kutta equations were used to obtain the numerical solution. This approach improves the applicability of the model by avoiding the assumption that the concentration ratio between Ba2+ and SO42- at the core entrance is much less than 1 in solving the model, which has been used in models reported by domestic and international researchers. Then, the concentration of Ba2+ at the outlet end of the core was determined by the transient displacement experiment with the core, and two important coefficients in the model-diffusion coefficient and reaction rate constant-were deduced by inversion of the concentration data. Finally, the distribution of barium sulfate scale in the core with different PVs and injection water with low SO42- concentration was studied. The results show that with increasing displacement volume, the amount of barium sulfate scale in the core increases, and the amount of scaling along the direction of the core length first increases and then decreases. The location with the maximum amount of scaling in the core moves towards the center of the core.

Key words: barium sulfate scaling, formation damage, kinetic model, finite difference

中图分类号: