一个冰-空气-水-NAPL多相模型,用于模拟NAPL在结-解条件下的地下系统中的NAPL迁移
Xiaoqin Fu1, Amalia Kokkinaki2, Xiaoqing Shi1
1School of Earth Sciences and Engineering, Nanjing University, Key Laboratory of Earth Fissures Geological Disaster, Ministry of Natural Resources, Nanjing 210023, China.
Journal of contaminant hydrology
|June 22, 2023
概括
本研究引入了一个新的非水相液体 (NAPL) 在寒冷地区的迁移模型,占四个阶段:冰,空气,水和NAPL. 忽视结解周期会对NAPL分布预测产生重大影响.
科学领域:
- 环境科学 环境科学
- 地质科学 地质科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 非水相液体 (NAPL) 污染对环境构成风险.
- 当前的多相流模型往往忽略了冰的形成,限制了它们在寒冷地区的适用性.
- 准确的NAPL迁移建模对于有效的地下修复至关重要.
研究的目的:
- 开发和评估一个四相系统 (冰-空气-水-NAPL) 中NAPL迁移的合非异热多相运输模型.
- 评估融周期对NAPL在寒冷环境中的分布的影响.
主要方法:
- 开发了一种数学模型,其中包含了冰相和未结冰的水含量.
- 与模拟结解周期的2D实验对模型进行了验证.
- 评估了结对光 (LNAPL) 和密度 (DNAPL) 非水相液体运输的影响.
主要成果:
- 该模型与NAPL和度的实验数据 (R2 = 0.8803) 达成了很好的协议.
- 模拟显示了预测NAPL和度的显著差异 (高达48%的LNAPL,13%的DNAPL),当忽略结解效应时.
- 结解周期大大改变了NAPL的空间分布和潜在的修复效率.
结论:
- 开发的四相模型准确地模拟了NAPL在结解条件下的迁移.
- 忽视寒冷地区的冰形成和融化,导致NAPL运输中的预测错误相当大.
- 这些发现对于改善寒冷气候地区的地下修复策略至关重要.
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