化工学报 ›› 2021, Vol. 72 ›› Issue (10): 5114-5122.DOI: 10.11949/0438-1157.20210374

• 流体力学与传递现象 • 上一篇    下一篇

纳米粒子在多孔介质中迁移模型的优化

彭爱夏(),占敬敬(),吴明火   

  1. 大连理工大学海洋科学与技术学院,辽宁 盘锦 124221
  • 收稿日期:2021-03-12 修回日期:2021-05-18 出版日期:2021-10-05 发布日期:2021-10-05
  • 通讯作者: 占敬敬
  • 作者简介:彭爱夏(1995—),女,硕士研究生,pengaixia@mail.dlut.edu.cn
  • 基金资助:
    国家自然科学基金项目(21876022);国家重点研发计划项目(2019YFC1803803)

Optimization of nanoparticles transport model in porous media

Aixia PENG(),Jingjing ZHAN(),Minghuo WU   

  1. School of Ocean Science and Technology, Dalian University of Technology, Panjin 124221, Liaoning, China
  • Received:2021-03-12 Revised:2021-05-18 Online:2021-10-05 Published:2021-10-05
  • Contact: Jingjing ZHAN

摘要:

当前,纳米粒子在土壤等多孔介质中的传输多采用单集去除率(η)进行定量描述。然而,单集去除率仅考虑单个介质颗粒对纳米粒子的作用,并未考虑介质颗粒之间的孔隙对纳米粒子的拦截效应,如T-E模型。鉴于此,采用持水度(fr)来定量反映多孔介质的孔隙特征,并对现有的T-E模型进行了修正。实验表明,纳米粒子通过具有相同孔隙度(f)砂柱的穿透率并不相同,且与持水度(fr)呈反比关系。在此基础上,将截留机制产生的碰撞效率(ηI)调整为与孔隙度(f)和持水度(fr)同时相关的表达式来实现对原有模型的优化。此外,通过砂柱对纳米二氧化硅(nSiO2)的传输实验和纳米二氧化钛(nTiO2)在不同粒径石英砂中的传输实验证明,优化模型适用于不同粒径的多孔介质并可以更准确地预测纳米粒子在多孔介质中的迁移。

关键词: 粒子, 多孔介质, 迁移, 模型, 孔隙

Abstract:

At present, the transport of nanoparticles in porous media such as soil is mostly described by a single-collector removal efficiency (η). However, this efficiency only considers the collecting effect of a single solid matrix, and does not consider the trapping effect of the pore space between the porous media such as T - E model. To address this issue, the water retention capacity (fr) was employed to reflect the number of small pores and the existing T-E model was modified. Research has shown that the transport of nanoparticles through columns with the same porosity (f) is not the same, but inversely proportional to the water retention capacity, which has been neglected in previous research. On this basis, the collector contact efficiency by the interception mechanism (ηI) is adjusted to be dependent on both porosity (f) and water retention capacity (fr); thus, the original model was optimized. Furthermore, breakthrough experiments on nanoscale silica particles (nSiO2) through the sand column and breakthrough experiments on nano titanium dioxide (nTiO2) through the sand column with different particle sizes proved that the optimized model is applicable to porous media with different particle sizes and is more accurate in predicting the transport of nanoparticles in porous media.

Key words: particle, porous media, particle transport, model, pore

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