Sharif Digital Repository

About 20% of total oil in the world is reserved in fractured reservoirs and there is also more than 60% of remained oil in the world in these reservoirs. But increasing recovery factor and production from this type of reservoirs was not very successful. After water flooding process most of the oil remains in the reservoir. The amount of remained oil is much more specially in fractured reservoirs. Surfactant flooding in one of the well-known enhanced oil recovery methods for reduction of interfacial tension between fluids to decrease capillary forces that cause less oil trapping and higher oil recovery. But a comprehensive and accurate understanding of the mechanism of this process and... 

Since physical variables are almost dependent, uncertain and have significant time and spatial changes, nature of hydrological and environmental systems is so complicated, nonlinear and dynamic. Many models have been developed for studying and analyzing various phenomena in these systems. Recently data mining approaches have been used as new methods for modeling of complicated engineering systems. In this study, performance of several data mining tools in analyzing two phenomena in water quality management have been evaluated. These algorithms are Multilayer Perceptron Neural Network (MLP), Radial Basis Function Neural Network (RBFN), Support Vector Machines (SVMs) in the field of Artificial... 

Due to the increasing relationships, and expand the transportation of goods and fuel by ships and other factors may also cause the release of pollution into the sea, Oil and also its derivatives are the dangerous pollutants that threaten the health of the environment and may destroy the local ecosystem.One of its highly carcinogenic pollutants that even inhaled,is furfural. A new and efficient method for the filtration of toxic substances and hazardous wastewaters, using the moving bed biofilm reactor treatment that is MBBR system. Microorganisms present in the reactor, that was used in this project, from the microorganisms of industrial Behran Company. Removal of furfural from the harsh... 

Evaporation is the most important water loss from terminal lakes which can influence the chemistry of lakes. In large lakes, the spatial distributions of meteorological and water quality variables affect the evaporation rates. Therefore, it is crucial to consider such variations in estimating evaporation rates from large lakes. This study aims at developing an evaporation estimation model for saline lakes considering salinity and spatial distribution of variables in/over the lakes and investigating the interaction between meteorological, hydrological and water quality variables in natural saline systems. To accomplish these objectives, first a distributed model was developed for estimating... 

The study of low-salinity water flooding or smart water flooding as secondary or tertiary oil recovery methods started in 1960 and many researchers have studied the effect of ions types on asphaltene precipitation/deposition during the injecting water into the oil reservoirs. To reduce the asphaltene challenges, one needs to properly investigate this phenomenon and better understanding of the cause of precipitation. It is already known that the amount of asphaltene deposition can be reduced by controlling the deposition criteria. For example, water microemulsion in the oil phase would cause the asphaltenes to be adsorbed on the water oil interface by hydrogen bonds due to heteroatom... 

Considering the significant impact of salinity and temperature on the life of aquatic ecosystems, the growth of plants and animals, and the health of people; it is necessary to predict the spatiotemporal distribution of these qualitative characteristics in aquatic environments by using precise algorithms through hydrodynamic models. This research presents an improved algorithm for calculating qualitative characteristics of aquatic environments, such as salinity, during the wet/drying processes. The developed algorithm in this study has been incorporated into FVCOM which is a three-dimensional hydrodynamic model. The current algorithm governing the FVCOM model is not capable of accurately... 

Lake Urmia is the largest inland lake of Iran and one of the most important water ecosystems in Iran and the world. The ecosystem of this lake is a typical example of a closed drainage basin into which all the runoff flows in the rivers of the basin are discharged. Because of its unique natural and ecological features, Urmia Lake has been declared as a national park since 1346, along with Kabudan and Qion Daghi islands, among the protected areas. Among the most important invertebrates in the lake, we can mention Artemia, which is a species of saltwater shrimp and one of the native species of Lake Urmia. This species is the most important source of food for many water birds such as flamingos.... 

Lake Urmia is the largest hypersaline lake in Iran, as well as a significant aquatic habitat. In recent decades, extreme increasing of extent plans and exploitation of water resources in this basin, cause decreasing inflow, water level and creating several environmental and economic issues. In recent decades, the excessive expansion in the development and exploitation of this basin's water resources has resulted in a drop in the flows into the lake, a decline in the lake's water level, and the creation of several environmental and economic issues. In recent years, these stressors have caused the lake's salinity to exceed 400 g/L, and salt deposits have emerged on the lake bottom and...