Petroleum Engineering – Reservoir
Vahid Karamnia; Siavash Ashoori
Volume 10, Issue 1 , January 2021, , Pages 107-126
Abstract
< p>One of the most important factors through the miscible gas injection process is to determine the Minimum Miscibility Pressure. According to the definition, the minimum miscibility pressure is the minimum pressure at which, at a constant temperature, the oil and gas injected can dissolve together ...
Read More
< p>One of the most important factors through the miscible gas injection process is to determine the Minimum Miscibility Pressure. According to the definition, the minimum miscibility pressure is the minimum pressure at which, at a constant temperature, the oil and gas injected can dissolve together to form a single phase. This pressure is typically abbreviated as MMP. Among the available methods for determining the minimum miscibility pressure, laboratory methods including slim tube test and ascending bubble apparatus test are more widely utilized. Although the mentioned tests have high measurement accuracy, they are very time consuming and expensive. Therefore, the determination of the minimum miscibility pressure is usually done using computational and simulation approaches that also have high accuracy. Conducting PVT tests and determining their MMP using slim tube method was previously performed. In this study, the minimum miscibility pressure of reservoirs was determined by applying three methods of simulation with PVTi software, simulation with Eclipse 300 software and using Empirical Correlations. By comparing the obtained results and the laboratory results, it was revealed that the simulation by Eclipse 300 is regarded as the fastest and most accurate approach.
Petroleum Engineering
Mostafa Jafari; Mohammad shahab Deljoo; Ali Vatani
Abstract
Today, one of the challenging issues all over the world is the appropriate use of flare gases in oil, gas, and petrochemical industries. Burning flare gases having high heating value results in economic losses and the pollution of the environment. There are several methods to use flare gases; the heat ...
Read More
Today, one of the challenging issues all over the world is the appropriate use of flare gases in oil, gas, and petrochemical industries. Burning flare gases having high heating value results in economic losses and the pollution of the environment. There are several methods to use flare gases; the heat and power generation, the production of valuable fuels, or the separation of more precious components are examples of these methods. In this study, a polygeneration system is designed and simulated for the coproduction of power, steam, methanol, H2, and CO2 from the flare gases in South Pars and Assaluyeh gas fields. The polygeneration system has advantages such as reducing greenhouse gases and the coproduction and sales of energy-related products. The polygeneration system for converting flare gases to energy and various products includes an acid gas removal unit, a synthesis gas production unit, a methanol synthesis unit, a hydrogen purification unit, a combined heat and power generation unit, and a CO2 capture unit. The purpose of this study is to conduct an economic evaluation of the polygeneration system and obtain the total capital cost, the operating profit, and the payback period of this process. The simulation results show that using 9690 kg/h of flare gases produces 8133 kg/h methanol, 653.7 kg/h hydrogen, 46950 kg/h nitrogen, 9103 kg/h CO2, 109850 kg/h medium-pressure steam, and 3.7 MW power. The economic evaluation results show that in the polygeneration system, the total raw material cost and the total utilities consumption cost are $193.8 and $1859.5 per hour respectively, and the total product sales and the total utility sales are $12941.8 and $2243.5 per hour respectively; also, the operating profit is $13132 per hour. Also, the equipment cost, the installation cost, the total capital cost, and the total operating cost are $29.7 million per year, $39.2 million per year, $71 million per year, and $27.9 million per year respectively; finally, the payback period is 1.5 years.
Petroleum Engineering
Arezou Jafari; Peyman Sadirli; Reza Gharibshahi; Esmaeel Kazemi Tooseh; Masoud Samivand; Ali Teymouri
Abstract
Natural gas storage process in aquifer, due to fluid flow behavior of gas and water in the porous medium and because of their contact with each other under reservoir conditions, faces several challenges. Therefore, there should be a clear understanding of the injected gas behavior before and after the ...
Read More
Natural gas storage process in aquifer, due to fluid flow behavior of gas and water in the porous medium and because of their contact with each other under reservoir conditions, faces several challenges. Therefore, there should be a clear understanding of the injected gas behavior before and after the injection into the reservoir. This research simulates the natural gas storage in aquifer by using Eclipse 300 software. For this purpose, a core sample was considered as the porous medium for gas injection, and a composition of natural gas was injected into the core in different conditions. Moreover, by using Plackett-Burman method, all of the factors affected in this process were screened, and finally four main significant parameters, including the flow rate of injected gas, permeability, pressure, and irreducible water saturation were selected for designing a design of experiments (DOE) plan. Response surface method (RSM) is one of the best methods of experimental design used for optimizing the process and finding the best combination of parameters to have a high stored gas volume and a high recovered gas volume. The simulation includes 28 runs with four considered parameters, and the output is the recovered gas, which in turn is vital for the process accomplishment. Sensitivity analysis and grid independency test were checked. To this end, three grids with different number of cells in x-direction were generated, and by analyzing the results of gas saturation in the porous medium for each model, a grid with 11250 cells (50 elements in x-direction and 15 elements in y- and z-directions) was then chosen as the main grid. Uncertainty analysis and the validation of numerical simulations were carried out, and good agreement was observed between the numerical results and experimental data. In addition, the numerical results showed that the flow rate of the injected gas had a significant impact on the process in comparison with other parameters. Furthermore, increasing permeability and decreasing pressure and irreducible water saturation raise the amount of trapped gas in aquifers. Therefore, for having the maximum stored gas volume and a high recovered gas volume, the best combination of parameters is a high gas injection flow rate (0.9 cc/min), high permeability (1.54 md), a low pressure (2254 psi), and irreducible water saturation. (0.46). Finally, in a natural gas storage operation in an aquifer, both rock properties and operational parameters play important roles, and they should be optimized in order to have the highest amount of stored gas.
Amir Hosein Tahershamsi; Ahad Ghaemi; Mansour Shirvani
Abstract
In this study, liquid-liquid extraction process in a Kuhni extraction column was modeled and simulated. A non-equilibrium dynamic model was developed for modeling liquid-liquid extraction processes based on a rate-based model. The model equations are inclusive of partial and ordinary differential equations ...
Read More
In this study, liquid-liquid extraction process in a Kuhni extraction column was modeled and simulated. A non-equilibrium dynamic model was developed for modeling liquid-liquid extraction processes based on a rate-based model. The model equations are inclusive of partial and ordinary differential equations which were discretized in column height direction. The population balance model was used for the calculation of droplet size distribution in the dispersed phase and the column hydrodynamic parameters. The equations were solved simultaneously through the finite difference method and the numerical method of lines. Experimental data on a bench scale Kuhni extraction column was used to evaluate the simulation results. The average correlation coefficient error of the mean diameter of the dispersed phase and mass transfer in various operating conditions are less than 2% 4 % respectively. A comparison between the experimental data and the simulation results proves the better productivity of the presented non-equilibrium dynamic model.
Mohammad Hasan Badizad; Ahmad Reza Zanganeh; Amir Hossein Saeedi Dehaghani
Abstract
Fracture reservoirs contain most of the oil reserves of the Middle East. Such reservoirs are poorly understood and recovery from fractured reservoirs is typically lower than those from conventional reservoirs. Many efforts have been made to enhance the recovery and production potential of these reservoirs. ...
Read More
Fracture reservoirs contain most of the oil reserves of the Middle East. Such reservoirs are poorly understood and recovery from fractured reservoirs is typically lower than those from conventional reservoirs. Many efforts have been made to enhance the recovery and production potential of these reservoirs. Fractured reservoirs with high matrix porosity and low matrix permeability need a secondary or EOR technique to achieve the maximum production. One of the effective EOR approaches is surfactant flooding, which reduces interfacial tension and alters wettability. Due to the complexity and uncertainty associated with such reservoirs, implementing a simulation and numerical analysis is primarily necessary to evaluate the effect of key engineering parameters on ultimate reservoir performance. This study assesses and provides a good insight into surfactant injection into fractured reservoirs using ECLIPSE software as a numerical simulator. The influences of fracture-matrix permeability ratio, initial water saturation, and the number of grids on reservoir performance were assessed and a sensitivity analysis was carried out. This study takes surfactant-related phenomena such as adsorption, surface tension reduction, and wettability alteration into account. The simulation results demonstrate that fracture-matrix permeability ratio is an important screening quantity for the selection of surfactant flooding as an EOR agent and that uncertainty in the initial water saturation of matrix has a great influence on the simulation outputs.
Maryam Pahlavan; Mohammad Ali Fanaei
Abstract
Reaction furnace is the most important part of the Claus sulfur recovery unit and its performance has a significant impact on the process efficiency. Too many reactions happen in the furnace and their kinetics and mechanisms are not completely understood; therefore, modeling reaction furnace is difficult ...
Read More
Reaction furnace is the most important part of the Claus sulfur recovery unit and its performance has a significant impact on the process efficiency. Too many reactions happen in the furnace and their kinetics and mechanisms are not completely understood; therefore, modeling reaction furnace is difficult and several works have been carried out on in this regard so far. Equilibrium models are commonly used to simulate the furnace, but the related literature states that the outlet of furnace is not in equilibrium and the furnace reactions are controlled by kinetic laws; therefore, in this study, the reaction furnace is simulated by a kinetic model. The predicted outlet temperature and concentrations by this model are compared with experimental data published in the literature and the data obtained by PROMAX V2.0 simulator. The results show that the accuracy of the proposed kinetic model and PROMAX simulator is almost similar, but the kinetic model used in this paper has two importance abilities. Firstly, it is a distributed model and can be used to obtain the temperature and concentration profiles along the furnace. Secondly, it is a dynamic model and can be used for analyzing the transient behavior and designing the control system.
