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In this paper, first a fuzzy random resource-constrained project scheduling problem is presented. The object of the problem is to find the optimal scheduling of project activities. In this model, duration of project activities is a fuzzy random variable. Then, the proposed model is formulated by using the expected value of fuzzy random variables as an IP model. An illustrative example is also provided to clarify the concept. © 2010 World Academic Press, UK. All rights reserved  

Gas injection is the second largest enhanced oil recovery process being applied in many reservoirs around the world. Simulation of these processes is necessary for implementation, management, and decision making. Relative permeability is one of the most important factors in numerical reservoir simulation. In this study, several core flood experiments are done and the relative permeability in carbon dioxide (CO2) injection is compared with nitrogen (N2) injection. Oil relative permeability in CO 2 injection is found to be higher than in N2 injection, but gas relative permeability in CO2 injection is found to be lower than in N2 injection. Higher oil relative permeability in CO 2 injection... 

Steam-assisted gravity drainage is one of the most promising strategies to develop huge heavy oil and bitumen accumulations. Like the other thermal processes, this method aims at reducing oil viscosity by increasing the temperature. But in an economical point of view, it requires a great volume of steam for injection. Moreover, early breakthrough of steam and high steam-oil ratio makes it uneconomical, especially in long production time. In this study, a new method, two wells cyclical steam-assisted gravity drainage is compared with a conventional steam-assisted gravity drainage process. Well configuration in two wells cyclical steam-assisted gravity drainage is the same as the... 

CO2 flooding has been recognized widely as one of the most effective enhanced oil recovery (EOR) technologies for reducing greenhouse emissions while increasing the ultimate recovery of oil reservoirs. Because of the wide variety of parameters that can influence, the outcome of CO2 storage projects reservoir simulation has gained wide popularity. In this study, a fully compositional reservoir simulation model was used to simulate various operational conditions, reservoir properties and fluid composition, and their effects on the amount of CO2 stored and oil recovered. The results can be used for selection of best reservoir candidates for carbon storage and optimization of operational... 

The relative permeability curves are key factors for assessment of reservoir performance by numerical simulators. The widely used one-parameter models are not sufficiently flexible for fitting laboratory measured relative permeability data. These models only show a concave upward trend and cannot represent the S-shape behavior of relative permeability. The other three-parameter models are too complex to use in practical reservoir engineering calculations. In this paper, a novel two-parameter model is proposed that maintains the simplicity of previous models while having great flexibility over a full range of saturation. The two parameters L and U control the shape of the lower and upper part... 

Carbon dioxide-oil relative permeability is measured under reservoir condition using core flood apparatus. Then the results are compared with Nitrogen-oil relative permeability. The results show that oil permeability is higher in Carbon dioxide injection compared to nitrogen injection. The comparison of gas permeabilities shows that at the start of injection, nitrogen and carbon dioxide relative permeability are equal, but as the gas saturation increased, Nitrogen relative permeability becomes higher. Finally, a method is proposed to calculate carbon dioxide-oil relative permeability from nitrogen-oil relative permeability. This method can be generalized to calculate relative permeability... 

An integrated model is proposed for simultaneous study of CO2-flood enhanced oil recovery and sequestration in both technical and economic points of view. Based on this model, Green Balance software is developed for quick estimation of performance and profitability of CO2-flood enhanced oil recovery and carbon capture and storage projects. This software benefits users to do sensitivity analyses in extended times, easily and quickly. Several sensitivity analyses were done and effects of reservoir parameters and economic expenditures and taxes were studied. Among all affecting parameters, the role of tax per CO2 emission is the most important one. The use of... 

The authors studied deposition and entrainment of asphaltene particles as major mechanisms that occur in porous media. Deposition mechanisms that contribute to permeability reduction and entrainment of deposited particle improve the damaged permeability value. While in most previous works the effects of entrainment mechanism are considered negligible, in this study miscible CO2 injection tests were conducted by core flood apparatus to investigate the effect of asphaltene deposition on permeability and porosity alterations. Results indicated that proposed model for entrainment mechanism is affected by deposition mechanism. The asphaltene deposition core's characteristics have undeniable roles...