Article Per Year (5 Year)
p-Index From 2021 - 2026
0
P-Index
This Author published in this journals
All Journal Scientific Contributions Oil and Gas
Ego Syahrial
Unknown Affiliation
Chemical Engineering, Chemistry & Bioengineering Energy

Published : 10 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 10 Documents
Search

 1 
A NEW APPROACH OF COMPOSITIONAL SIMULATION FOR A VOLATILE OIL RESERVOIR MODELING Ego Syahrial
Scientific Contributions Oil and Gas Vol 33 No 1 (2010)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.33.1.658

Abstract

This paper proposes a new compositional simulation approach for a volatile oil reservoirmodelling. The proposed formulation has an implicit equation for the oil-phase pressureand water saturation, an explicit equation for the hydrocarbon saturation, and explicitequation for the overall composition of each hydrocarbon component that satisfiesthermodynamic equilibrium. An Equation of State for phase equilibrium and property calculationsis used in this new formulation. Interfacial tension effects are included in thisapproach to characterise the thermodynamically dynamic nature of the relative permeability.A two-dimensional relative permeability algorithm is included which handles lumpedhydrocarbon phase hydrocarbon phase as well as individual phase flows. For each gridblock two equations are required, namely total hydrocarbon and water-phase flow equations.These equations are highly non-linear and they are linearised by using Newton-Raphson method. The resulting equations are solved by an efficient Conjugate Gradientbased iterative technique to obtain pressures and saturations simultaneously, and hydrocarbon-phase saturations are deduced from their respective equations.The new compositional simulation approach is validated through analytical and numericalmethods. It is demonstrated in this present paper that the results are comparedfavourably with analytical techniques and published numerical results. They also confirmthat the proposed codified formulation is unconditionally stable and it is as stable as fullycompositional model yet the computational cost reduction was substantial.
Application of New Compositional Simulation Approach to Model Gravity Segregation In Volatile Oil Reservoirs Ego Syahrial
Scientific Contributions Oil and Gas Vol 33 No 3 (2010)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.33.3.661

Abstract

In this paper, we investigate the recovery performance of gas injection from volatile oilreservoirs. Cross-sectional reservoir studies for investigating the gravity segregation duringdepletion and gas cycling in volatile oil reservoirs is discussed. Furthermore the effectsof vertical permeability on gravity segregation in a homogeneous and horizontal reservoirsare investigated.A new efficient compositional simulation approach was used in this study to investigatethe influence of gravity segregation and their magnitude in the case of lean gas injectioninto a volatile oil reservoir. The new compositional simulation approach was validatedthrough analytical and numerical methods, and it is unconditionally stable and as stableas fully compositional model.The results show that an increase in vertical to horizontal permeability ratios results inan increase in the effect of gravity segregation and yield early gas breakthrough. On theother hand, the smaller the permeability ratios (vertical to horizontal), better are the recoveriesdue to resulting even layer sweeps. Gravity forces have a considerable effect onvolatile oil recovery via gas injection and the need for determining not only the fluidcharacteristics but also the reservoir heterogeneities was significant.
Effect Of Composition Variation With Depth On Volatile Oil Reservoirs Ego Syahrial
Scientific Contributions Oil and Gas Vol 33 No 1 (2010)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.33.1.809

Abstract

It has been known that the distribution of hydrocarbon components in a fluid column is affected of gravity. Many authors have shown the effect of composition variation within a hydrocarbon column due to gravity. In thick reservoirs as the depth increases, the mole fraction of the lighter hydrocarbon decreases, whereas the heavy fraction increases. These variations may affect reservoir fluid properties considerably. In studying reservoir processes, especially with miscible displacements, it is essential to have of underlying mechanisms. In this paper, we investigate the effect of composition variation with depth on volatile oil under depletion and miscible gas processes. A ternary diagram was used to identify the process displacement mechanisms at different locations. A new efficient compositional simulationapproach was used to model the volatile oil reservoir bahaviour. It was shown that the decreasing light component with depth caused different miscible displacement processes as the oil composition move toward limiting tie line in the ternary diagram. Saturation and reservoir pressures variation with depth were not linear in a thick reservoir. This non linearity increased with the increased in volatility of the oil. In the case of depletion, the concentration of light component decreased below its original composition in the produced layers. In vaporising-gas drive the light component gradually vaporized from the bottom to the top of reservoir, whereas the intermediate component decreased below its original composition from the bottom to the top of the reservoir
Understanding Carbon Capture And Storage (Ccs) Potential In Indonesia Ego Syahrial; Usman Pasarai; Utomo P Iskandar
Scientific Contributions Oil and Gas Vol 33 No 2 (2010)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.33.2.816

Abstract

National energy policy drawn up by the government through Energy Mix Target 2025 (Presidential Regulation No.5/2006) is still dominated by fossil fuel. Moreover, it is coupled with high dependence on fossil fuel, increasing demand of energy and standard of living and high rate population growth, it can turn Indonesia into one of the biggest emitter in the future. On 2009, the government has pledged a non-binding commitment to reduce country emissions by 26% in 2020. This aspiring target requires great efforts besides reliying on current strategies such as energy mix improvements, the switch to less-carbon intensive fuels and renewable resources deployment as well as conservation. Carbon Capture and Storage (CCS) is one of the climate change mitigation tools with the technological capability to reduce CO2 in substantial amount and deep cut particularly on energy sector. CCS is typically defined as the integrated process of CO2 separation at industrial plants, transportation to storage sites and injection into subsurface formations. This paper explains the possibility of CCS potential deployment in Indonesia by reviewing required components and provides comprehensive understanding in each CCS key lements.
Modeling Gravity Segregation In Stratified And Dipping Reservoir Of Volatile Oil Ego Syahrial
Scientific Contributions Oil and Gas Vol 33 No 3 (2010)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.33.3.822

Abstract

In this paper, we investigate gravity segregation in stratified and dipping reservoir of volatile oil under gas injection. A new efficient compositional simulation approach was used in this study to investigate the influence of gravity segregation and their magnitude in the case of gas injection into a volatile oil reservoir. The results show that in stratified and dipping reservoirs where the permeability decreases with depth, smaller the vertical to horizontal permeability ratio, lesser is the effect of gravity segregation, better is the sweep efficiency and hence better is the recovery. In the case of increasing permeability with depth in stratified dipping reservoirs, an up-dip gas injection into a volatile oil reservoir was found to be a favourable condition in term of recovery. Gravity forces have a considerable effect on volatile oil recovery via gas injection and the need for determining not only the fluid characteristics but also the reservoir heterogeneities was significant
Effects Of Matrix Swelling On Coal Permeability For Enhance Coalbed Methane (Ecbm) And Co2 Sequestration Assessment Part Ii: Model Formulation And Field Application Ego Syahrial
Scientific Contributions Oil and Gas Vol 32 No 1 (2009)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.32.1.832

Abstract

In part II of this two-part paper series, a field permeability model for enhanced methane recovery and CO2 sequestration, incorporating the findings of the current laboratory tests presented in part I is presented. It has been reported that coal matrix swelling/shrinkage associated with CO2, adsorption/desorption are typically two to five times larger than that found for methane, yet there has been no direct measurements of this effect on permeability of coals to CO2. The feasibility of ECBM/CO2 sequestration technology depends very much on the magnitude of matrix swelling effect on permeability, especially in deep, low permeability coal seam reservoirs. The main objective of this research is to investigate and develop numerical models based on the the effects of coal matrix swelling induced by CO2 adsorption on the permeability of different coals which have been undergoing methane desorption under simulated reservoir conditions in the laboratory.
A New Procedure For Reservoir Fluid Characterization With Equation Of State (EOS) Ego Syahrial
Scientific Contributions Oil and Gas Vol 32 No 2 (2009)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.32.2.837

Abstract

A new procedure for reservoir fluid characterization through equation of state (EOS) is proposed. It is applied in a selecting the most appropriate fluid composition for the purpose of reservoir fluid characterization. A Hoffman-Crump-Hocott plot is used to determine whether or not the streams are genuine equilibrium fluids. With the aid of phase diagram and saturation pressure from RFT, the most appropriate fluid sample was chosen for fitting an equation of state to experimental data through regression. Based on data analysis and quality control of all PVT data suggested that fluid from UP-1 DST-3 is the best representative of XYZ field. The PR3-EOS and LBC correlation are applied to the UP-1 DST-3 data sets under conditions of predictions and regression. Agreement between laboratory data and regressed EOS results is generally good to excellent. The results show that that regression on critical properties of components is sufficient for good data matches. In this work, a good agreement with experimental data was obtained with grouping (lumping) 15 to 7 components.
Reservoir Simulator For Improved Recovery Of Coalbed Methane (Icbm) Part I: Model Formulation And Comparison Ego Syahrial
Scientific Contributions Oil and Gas Vol 32 No 3 (2009)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.32.3.848

Abstract

Sequestration of CO2 in deep unmined coal seams is currently under development for improved recovery of coalbed methane (ICBM) as well as permanent storage of CO2. Recent studies have shown that CO2 displaces methane by adsorbing more readily onto the coal matrix compared to other greenhouse gases, and could therefore contribute towards reducing global warming. In order to carry out a more accurate assessment of the potential of ICBM and CO2 sequestration, field based numerical simulations are required. Existing simulators for primary CBM (coalbed methane) recovery cannot be applied since the process of CO2 injection in partially desorbed coalbeds is highly complex and not fully understood. The principal challenges encountered in numerical modelling of ICBM/CO2 sequestration processes which need to be solved include: (1) two-phase flow, (2) multiple gas components, (3) impact of coal matrix swelling and shrinkage on permeability, and (4) mixed gas sorption. The objective of this part I of this two-part paper series is to develop a two-phase, multi-component CH4-CO2 simulator for use in the assessment of CO2-ICBM recovery and CO2 sequestration potential of coal seams. The developed formulation was tested and compared to model the improved coalbed methane (ICBM) recovery with pure CO2 injection using a published data.
Reservoir Simulator For Improved Recovery Of Coalbed Methane (Icbm) Part Ii : Effect Of Coal Matrix Swelling And Shrinkage Ego Syahrial
Scientific Contributions Oil and Gas Vol 32 No 3 (2009)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.32.3.850

Abstract

Sequestration of CO2 in deep unmined coal seams is currently under development for improved recovery of coalbed methane (ICBM) as well as permanent storage of CO2. Recent studies have shown that CO2 displaces methane by adsorbing more readily onto the coal matrix compared to other greenhouse gases, and could therefore contribute towards reducing global warming. In order to carry out a more accurate assessment of the potential of ICBM and CO2 sequestration, field based numerical simulations are required. Existing simulators for primary CBM (coalbed methane) recovery cannot be applied since the process of CO2 injection in partially desorbed coalbeds is highly complex and not fully understood. The principal challenges encountered in numerical modelling of ICBM/CO2 sequestration processes which need to be solved include: (1) two-phase flow, (2) multiple gas components, (3) impact of coal matrix swelling and shrinkage on permeability, and (4) mixed gas sorption. This part II of this two-part paper series describes the development of a compositional simulator with the impact of matrix shrinkage/swelling on the production performance on primary and echanced recovery of coalbed methane. The numerical results for enhanced recovery indicate that matrix swelling associated with CO2 injection could results in more than an order of magnitude reduction in formation permeability around the injection well, hence prompt decline in well injectivity. The model prediction of the decline in well injectivity is consistent with the reported field observations in San Juan Basin USA. Also, a parametric study is conducted using this simulator to investigate the effects of coal properties on the enhancement of methane production efficiency based on published data.
Carbon Capture And Storage (Ccs) - Enhanced Oil Recovery (Eor): Global Potential In Indonesia Utomo Pratama Iskandar; Ego Syahrial
Scientific Contributions Oil and Gas Vol 32 No 3 (2009)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.32.3.855

Abstract

Total global CO2 emissions from fossil-fuel will still increase in the next ten decades. These are attributed to the heavy reliance of human activities with fossil fuels. The uncontrolled CO2 emissions from combustion of fossil fuels cause the CO2 concentration alteration in the atmosphere. As the result, this phenomenon cause global warming and change the climate globally. In the future, CO2 emissions are predicted in range from 29 to 44 GtCO2/year in 2020. Therefore it is necessary to abate the CO2  missions to the level that would prevent dangerous anthropogenic interference to the global climate system. The growth of energy efficiency improvements, the switch to less-carbon intensive fuels and renewable resources employment is still low in the context CO2 emissions mitigation. Carbon Dioxide Capture and Storage (CCS) as a third option for these mitigation options might facilitate achieving CO2  missions stabilization goals. As a part of the commitment and participation on combating the global warming, Indonesia has signed the Kyoto Protocol in 1998 and ratified it in 2004 through Law No. 17/2004. On the other side, Indonesia oil production has been declining since in the last ten years but demand for this energy is still high. In this frame CCS-Enhanced Oil Recovery (EOR) by CO2 injection might answer the global warming challenges and alongside contribute to increase the oil production in the near future. This paper presents a preliminary study of CCS-EOR potential in Indonesia. A brief explanation of geological setting and reservoir screening for site selection also presented. Then some discussions about CCS-EOR global potential will be highlighted as well as the analysis. It is hoped that this study would provide a standard guideline for determining CCS- EOR potential in Indonesia.
Co-Authors Usman Pasarai Utomo P Iskandar Utomo Pratama Iskandar