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The miscible displacement process appears to be an increasingly feasible method for the extraction of oil from depleted reservoirs. However, there is a lack of fundamental understanding of how fracture geometrical characteristics impact the oil recovery efficiency in this type of enhanced oil recovery technique. In this work, a series of experimental tests were conducted whereby the n-Heptane as a solvent displaced n-Decane in the glass micro-models having different fracture geometries. It has been observed that the breakthrough time is decreased with increasing the fractures' length. In contrast, breakthrough time is increased when increasing the fractures orientation angle related to flow... 

Impure rhenium and molybdenum bearing solution was passed through a column of Varian strong base anionic resin for selective adsorption of rhenium and molybdenum ions from the solution. Elution of molybdenum and rhenium was carried out using 2 N NaOH and 0.2 N NH4SCN, respectively. The effect of resin bed height on breakthrough time was investigated. Experimental and theoretical curves were compared with good agreement. The results showed that the behavior pattern of these curves was repeatable and almost constant. © 2006 Elsevier B.V. All rights reserved  

Fluid flow modeling in porous media has many applications in waste treatment, hydrology and petroleum engineering. In any geological model, flow behavior is controlled by multiple properties. These properties must be known in advance of common flow simulations. When uncertainties are present, deterministic modeling often produces poor results. Percolation and Random Walk (RW) methods have recently been used in flow modeling. Their stochastic basis is useful in dealing with uncertainty problems. They are also useful in finding the relationship between porous media descriptions and flow behavior. This paper employs a simple methodology based on random walk and percolation techniques. The... 

The connectivity of high conductivity pathways in geological formations depend on the spatial distribution of geological heterogeneities that may appear on various length scales. Appropriate modeling of this is crucial within in hydrology and petroleum systems. The approach taken in this study is to use percolation theory to quantify the connectivity, hydraulic conductivity, and breakthrough time behavior between an injector and a producer within such systems. In particular, a three-dimensional overlapping sandbody model is considered which assumes that the geological formation can be split into either conductive flow units (i. e., good sands) or non-conductive units (i. e., poor sands). The... 

The connectivity of high conductivity pathways in geological formations depend on the spatial distribution of geological heterogeneities that may appear on various length scales. Appropriate modeling of this is crucial within in hydrology and petroleum systems. The approach taken in this study is to use percolation theory to quantify the connectivity, hydraulic conductivity, and breakthrough time behavior between an injector and a producer within such systems. In particular, a three-dimensional overlapping sandbody model is considered which assumes that the geological formation can be split into either conductive flow units (i. e., good sands) or non-conductive units (i. e., poor sands). The... 

This paper investigates the efficiency and performance of several of the fiooding techniques popular in secondary and enhanced oil recovery. These processes include water fiooding, immiscible and miscible gas fiooding, and several forms of water-alternating-gas (WAG) injection. The study is carried out numerically on a typical one-dimensional domain using an advanced high-resolution central scheme. Some performance indices such as oil cut drop, breakthrough time, and sweep efficiency were employed to evaluate the appropriateness of each injection strategy  

The immiscible process appears to be one of the first feasible methods for the extraction of oil reserves. However, there is a lack of fundamental understanding of how fracture geometrical characteristics control the efficiency of oil recovery in this type of enhanced oil recovery technique. In this article, a series of experiments were conducted whereby the distilled water displaced n-decane in strongly oil wet glass micro-models having different fracture geometries. Breakthrough time, as a function of injected pore volume of distilled water, was measured using image analysis of the provided pictures. It has been observed that when the fractures' length is increased, the breakthrough time... 

In the current study, hydrogen fluoride (HF) adsorption onto the sodium fluoride pellets is modeled. For this purpose a two-dimensional, non-isothermal model was developed and the governing equations were solved numerically. The contributions of diffusion transport in axial and radial directions also were considered in mathematical formulations. The model results of effluent concentration and breakthrough curves of HF were compared with the experimental data obtained in a lab-scale adsorption unit, reported in our previous work [1]. The results indicate while the feed gas velocity decreases, the HF adsorption capacity on NaF is significantly enhanced and there is a delay in breakthrough... 

Determining the time of breakthrough of injected water is important when assessing waterflood in an oil reservoir. Breakthrough time distribution for a passive tracer (for example water) in percolation porous media (near the percolation threshold) gives insights into the dynamic behavior of flow in geometrically complex systems. However, the application of such distribution to realistic two-phase displacements can be done based on scaling of all parameters. Here, we propose two new approaches for scaling of breakthrough time (characteristic times) in two-dimensional flow through percolation porous media. The first is based on the flow geometry, and the second uses the flow parameters of a...