Incorporating hysteresis in a multi-phase multi-component NAPL modelling framework; a multi-component LNAPL gasoline example
Abstract
The longevity of chemicals in subsurface NAPL releases is a function of their partitioning into different phases. Hysteresis can affect distribution and partitioning of compounds in the vadose zone. We separated and modified hysteresis code from NAPL Simulator (which include hysteresis caused by fluid entrapment and capillary effects) and embedded it into TMVOC. For the first time, the resulting framework is used to model multi-component and multi-phase NAPL release, partitioning and transport. We then applied the verified framework to model effects of hysteresis on partitioning of BTEX, TMB and short and long chain alkanes from a typical gasoline spill. Excluding hysteresis resulted in an expanded LNAPL plume and underestimated the compounds longevity. Hysteresis altered the spatial distribution of LNAPL molar fractions as well as gas flow path and contaminants distribution compared to the non-hysteretic case. The amplifying effect of hysteresis on the longevity of mixtures (and associated risks) should be considered if non-hysteretic relationships are applied
Document Type
Journal Article
Date of Publication
2016
Location of the Work
United Kingdom
Publication Title
Advances in Water Resources
Publisher
Elsevier
School
School of Engineering
RAS ID
21862
Copyright
subscription content
Comments
Sookhak Lari, K., Davis, G. B., & Johnston, C. D. (2016). Incorporating hysteresis in a multi-phase multi-component NAPL modelling framework; a multi-component LNAPL gasoline example. Advances in Water Resources, 96, 190-201. Available here