Sharif Digital Repository

Because of the importance of simulations in the oil industry, there are different software applications designed for this purpose. The purpose of the simulation in the oil industry is to reduce operational errors during the operation and to achieve the most ideal mode of operation. However, in the simulation of multiphase fluid flow because of the special circumstance, simulation plays an important role in the oil industry. OLGA multiphase flow simulation software is a strong simulation software for water, oil, Gas wells, wellhead facilities, refineries and pipelines and it is capable of simulating pipelines under various dynamic conditions. Simulation of drilling hydraulic parameters is... 

During the over balanced drilling operation in high permeability or fractured formations, drilling fluid loss and in more severe occasions fluid lost occurs which causes many problems and dangers and delayed the drilling operation until it was repaired. On the one hand, because of the high value of this material, and on the other hand, due to the increase in rig/day costs resulting from lost circulation control, leads to a significant increase in drilling costs. In this research, polymer-fiber composites have been designed and manufactured using extrusion method and have been investigated as fluid lost control agent in the laboratory scale for the first time in Iran. The effective parameters... 

The aim of this project is designing Suitable drilling fluid applicable in deep drilling. This aim will be reached by adding a temperature-resistant polymers or nanomaterials in water-based drilling fluid, Rheological properties of drilling fluid checked. Stability of rheological properties of drilling fluids not constant in HT state. Chain of cause and effect will happen, While the temperature increases, the viscosity and yield point of the fluids decreases. cuttings transportation and removal efficiency will be decreased due to reduction in yield point and viscosity. Evaluation of The effect of these cases conclude that these effects will also impact on filtration loss. The reason is that... 

Underbalanced drilling is a type of drilling operation in which the pressure of the drilling fluid is less than the pressure of the formation. This pressure difference has created advantages for this method. Less formation damage, reduction of pipe stuck, increasing rate of penetration and production during drilling are the advantages of this method compared to traditional methods. To reduce the pressure of the drilling fluid, very low density fluids should be used. One way to reduce density is to mix a compressible fluid such as gas into water. Due to the difference in density and surface tensile strength of water and gas, these two phases do not combine, so a stable combination of these... 

During all operations in hydrocarbon reservoirs, there is a possibility of formation damage. These damages can reduce the production of fluids from reservoir. One of the major damages that can seriously affect the performance of a reservoir is the damage caused by drilling fluid. The main purpose of this research is to study the main mechanisms of formation damages when using oil-based drilling fluids and fixing or preventing these damages. Once the mechanisms are identified, it is tried to cure the damages but without acid-washing. The alternative method is surfactant-washing which is a surfactant-brine injection. This injection has been done for the first time. This study helps to industry... 

In recent years, utilizing the colloidal gas aphron (CGA) drilling fluids is getting more and more commonplace due to their little formation damage and filtration loss. This study tries to investigate the effect of presence of nanoparticles and their type (hydrophobicity) on stability and performance of water and oil based CGA drilling fluids. This is done through analyzing stability, filtration, rheology, and pore blockage tests. Water and oil based CGA drilling fluids consisted of stabilizer, surfactant, and nanoparticles are generated and through examining of the effects of polymer, surfactant, and nanoparticle concentrations, the optimum formulation is obtained. High pressure-high... 

During the drilling process, cutting concentration in vertical and inclined wells is a common problem and major issue in designing hydraulic parameters. This is becoming more important in near bit area. Cutting transport usually is affected by several parameters such as mud rheology, flow rate, nozzle size, rotation speed, and mud weight.
In this work it was aimed to design a new set-up to test all the factors on hole cleaning phenomenon especially in near bit area. The set-up consists of a 16 feet long flow loop, 3.28 feet height of the test section, and 3.33 inches inner diameter of the test section. Each parameter which has an impact on hole cleaning could be varied. The cutting... 

Nowadays, one of the most major problems in drilling industry is Lost Circulation in different formations. Lost Circulation increases non-productive time, expenditures and environmental damages. Lost Circulation can happen in natural or induced fractures, cavernous formations and high permeable rocks and it can be subcategorized in seepage, medium, severe or complete type based on the severity of the problem. For addressing this issue, different methods are suggested. One of the most considered of these methods is using Lost Circulation Materials (LCM). In this thesis, it was tried to manage the situation with Designing and engineering of lost circulation materials for different lost... 

Given that the mean of the cost of drilling operation related to the required martials and preparation of the drilling fluids, therefore, the design and construction drilling fluid which omit has to be a proper rheology is essential in drilling operations and oil industry. A desirable property of the drilling fluid is the minimum fluid loss volume which can be achieved by formation of a low permeability filter cake on the wellbore. Drilling fluid filtrating invasion into the formation can cause formation damage and reduction in the productivity of the well. In drilling fluids, a series of natural synthetic and polymers may be used as fluid (filtration) loss control additives. However, high... 

During all operations in oil and gas reservoirs, it is possible to cause formation damage. These damages can greatly reduce the rate of production. One of the major damages that can seriously affect the performance of a reservoir is the damage caused by drilling fluid. The main purpose of this thesis is to study the main mechanisms of formation damage caused by water-based drilling fluid using a glass micromodel for the first time. An accurate understanding of the mechanisms of formation damage can provide a good understanding of the selection of the type and concentration of materials used, as well as appropriate methods to control and eliminate damages. for controlling the drilling fluid...