The Influence of Crude Oil on Mechanistic Detachment Rate Parameters

Abstract

Iraqi soil contamination greatly influenced soil detachment. Previous researchers have not been able to predict the influence of crude oil soil contamination on either the mechanistic dimensional detachment parameter b0 or the threshold parameter b1 of the mechanistic detachment model (Wilson model). The aims of this research were (1) to investigate the influence of crude oil on deriving Wilson model parameters, b0 and b1, with two setups at different scales and different soil moisture contents and (2) to predict b0 and b1 in crude oil contaminated dry soils with varying levels of contamination. The “mini” JET apparatus was implemented under laboratory conditions for soil specimens packed at both a small (standard mold) and a large (in-situ soil box) scale. The results showed an inverse correlation between b0 and water content for clean soil. No correlation between b0 and soil moisture content was observed for contaminated soils. There was a huge reduction in the b0 value as the contamination time increased compared to the clean soil. This was related to the role crude oil plays in soil stabilization. Crude oil contamination significantly increased lead contamination level while slightly increasing the pH and total organic carbon. The influence of crude oil on mechanistic soil detachment can be predicted with a priori JET experiments on soils without crude oil based on crude oil parameters.

Assessment of Surface Water Resources of Eastern Iraq

“…The software recommended both Tukey test method and student-Newman-Keuls method to test all pairwise comparisons of the mean responses to different treatment groups. Thus, in this study, pairwise comparisons of t-tests are calculated for both observed and predicted flow rates using the Tukey test method and student-Newman-Keuls method, which revealed a significant difference compared to ANOVA with a significance level of α = 0.05 [25].…”

Study on Parameters of Two Widely Used Cohesive Soils Erosion Models

“…Wilson (1993aWilson ( , 1993b proposed a mechanistic detachment model to provide a general framework for studying soil and fluid characteristics [10,11]. The advantage of the Wilson model over the over-shear stress model is that the factors affecting erosion can be considered and evaluated in greater depth; this has been studied extensively by related scholars, incorporating factors such as turbulence, roughness, seepage forces, material soil orientation, root effects, and negative pore water pressure effects into the Wilson model [12][13][14][15][16]. The Wilson model was based on the balance of all the forces and moments driving and resisting detachment that would be preferred for modeling the range of possible environmental conditions, which is expressed as:…”

“…For the parameters in the scour model, it is also vital to determine their relationship with soil parameters. Hasan and Al-Madhhachi (2018) investigated the effect of crude oil on erosion parameters (b 0 and b 1 ) [13]. For clean soil and polluted soil, parameter b 1 increases with increasing water content.…”