Dissolution of multi-component LNAPL gasolines: The effects of weathering and composition

Gasoline Multiphase and Multicomponent Partitioning in the Vadose Zone: Dynamics and Risk Longevity

“…Mole fraction of representative groups in light nonaqueous‐phase liquid (LNAPL) for weathered ( W ) and 50% evaporated gasoline ( E ) (Lekmine et al, 2014), shallow ( S ), and deep ( D ) release and the total mass of LNAPL (bottom right subfigure)…”

“…Further redistribution of LNAPL after the release stage has also been studied for selected scenarios (see Changes in the Light Nonaqueous‐Phase Liquid Composition section). The composition of fresh gasoline is adopted from Lekmine et al (2014), where 25 components and their mole fractions were reported. We ignored the nine compounds contributing least to the gasoline ( n ‐propylbenzene; cyclohexane; iso‐octane; 1‐methyl,2‐ethylbenzene; 1‐methyl, 3‐ethylbenzene; 1‐methyl, 4‐ethylbenzene; naphthalene; 2‐methylnaphthalene; and 1‐methylnaphthalene) and considered the remaining 16 compounds.…”

A Single-Pole Approximation to Interfacial Mass Transfer in Porous Media Augmented with Bulk Reactions

“…1 This flows through an inclined homogeneous isotropic porous medium (equivalent to a pressure gradient to cause the fluids motion Sookhak Lari et al 2015). Fluid 1 is slightly soluble in fluid 2, as for example during the dissolution of some of the gasoline ingredients (as a typical LNAPL) into groundwater (Vayenas et al 2002;Johnston and Trefry 2009;Lekmine et al 2014). We assume that the flow for both fluids is governed by the Darcy-Brinkman equation (Neale and Nader 1974;Vafai and Tien 1981) …”

“…Groundwater contamination with NAPLs, such as petroleum hydrocarbons, is a significant global threat to the beneficial use of fresh water supply and can pose environmental and human health risks. Dissolution of the soluble components in NAPL petroleum hydrocarbons into groundwater [such as benzene and toluene into groundwater (Lekmine et al 2014)] can pose long-term risks to the public health and the environment (Sookhak Lari and Safavi 2008;Miller et al 2013). Therefore, it is of particular importance to quantify the rate of mass transfer between NAPLs and water as a function of ambient parameters such as fluid velocity and reaction of dissolved materials in aqueous phase.…”

Scenario-based modelling of mass transfer mechanisms at a petroleum contaminated field site-numerical implications

“…Since the spilled gasoline fuel contains large number of aliphatic, aromatic and polycyclic aromatic hydrocarbon (PAH) compounds, the estimation of effective solubility as explained by Raoult's law seemed to be inadequate to represent the actual partitioning behaviour, which largely depends on the molecular interactions (Peters et al, 1999). Deviations from ideal behaviour (when activity coefficients deviating from unity) can be due to many reasons, including chemical heterogeneity of the components of the mixture and their respective molar volumes which are not incorporated into the common application of Raoult's law (McCray and Dugan, 2002;Lekmine et al, 2014). It is also important to determine the combined effect of sorption and biodegradation which can remove the dissolved organic compounds, thus improving the source clean-up strategies (Couto and Malta, 2008;Natarajan and Suresh Kumar, 2010).…”