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Scientific Contributions Oil and Gas
Published by LEMIGAS
ISSN : 20893361     EISSN : 25410520     DOI : -
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Energy
The Scientific Contributions for Oil and Gas is the official journal of the Testing Center for Oil and Gas LEMIGAS for the dissemination of information on research activities, technology engineering development and laboratory testing in the oil and gas field. Manuscripts in English are accepted from all in any institutions, college and industry oil and gas throughout the country and overseas.
Arjuna Subject : Energi (semua kategori) - Teknologi Bahan Bakar
Articles 619 Documents
 1   2   3   4   5 
POLLEN RECORDS FROM THE OLIGOCENE OF WESTERN INDONESIA AS THE EVIDENCES OF CLIMATE CHANGES Eko Budi Lelono
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.46

Abstract

In Southeast Asia, Oligocene climate is well known to be represented by dry/ seasonal climate. However, it was reported possible appearance of wet climate period during the expantion of dry condition. This work is aimed to confi rm the Oligocene climate which occurred in western Indonesia. Climate change is useful to understand the Oligocene stratigraphy of Western Indonesia. This study uses cutting samples from off shore exploration wells situated in West and East Java and West Natuna as well as on-shore Central Sumatera and West Java. Samples are processed using standard preparation methods to produce suitable pollen assemblage for quantitative analysis.This study proves that the Oligocene sediments yield rich pollen assemblages including those of environment and climate indicators. Abundant fresh water algae of Pediastrum and Bosedinia in Early Oligocene indicates the appearance of lacustrine sediments. This sediment was formed under dry/ seasonal climate as marked by rich grass pollen Monoporites annulatus in the absence or rare occurance of rain forest elements. Mean while, Late Oligocene is characterised by common brackish elements to indicate shifting paleoenvironment into transition to shallow marine. The climate was changing into wetter condition as evidenced by high appearance of Dacrydium and Casuarina as well as other rain forest palynomorphs. The wettest climate probably occured in Java region which refl ected a wet climate fringe to the eastern margin of Sundaland prior to the collision of the Australian and Asian Plates at the Oligo-Miocene boundary. However, in general, dry/ seasonal climate is the rule for most of the Oligocene in Western Indonesia.
THE EFFECT OF ANIONIC AND NONIONIC CO-SURFACTANT FOR IMPROVING SOLUBILITY OF POLYOXY-BASED SURFACTANT FOR CHEMICAL FLOODING Yani Faozani Alli; Dadan Damayandri; Yan Irawan
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.49

Abstract

Surfactant is one of the crucial components for chemical flooding to recover oil production in the tertiary stage of the low primary and secondary recovery oil field. The mechanism is performed by decreasing the interfacial tension of oil and water which enhancing microscopic displacement efficiency. The present study showed the effect of commercial nonionic and anionic co-surfactant Tergitol, Teepol, Merpol, and SDS on the solubility of polyoxy based-surfactant (POS) through compatibility analysis, fi ltration ratio analysis, and IFT measurement. Whereas the presence of Teepol and Merpol did not change the original compatibility of POS in all concentrations, the addition of co-surfactant Tergitol and SDS were able to alter the solubility of POS from milky solution into a clear transparent solution. However, the most important characteristic of surfactant for reducing the IFT of oil-water was affected by the addition of co-surfactant which does not have sufficient IFT to release the trapped oil in the reservoir. Thus, exposing the mixture of surfactant and co-surfactant for a few days at the reservoir temperature has changed the visual appearance of solution from a clear transparent solution into a milky suspension, indicating the occurrence of thermal degradation. These results suggest that the addition of anionic and nonionic co-surfactant improved the solubility of POS, but increased the IFT. It can be concluded that the compatibility of POS in the brine can then be achieved by mixing it with suitable co-surfactant. Screening the other co-surfactant is required to obtain the one that enhances the compatibility as well as maintaining the ultralow IFT of POS.
SPECTRAL DECOMPOSITION TECHNIQUE BASED ON STFT AND CWT FOR IDENTIFYING THE HYDROCARBON RESERVOIR Abdul Haris; Haryono Haryono; Agus Riyanto
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.50

Abstract

The spectral decomposition is one of the advanced interpretation techniques such as seismic inversion, amplitude versus offset analysis, and seismic attribute that helpful in direct interpretative approach in seismic exploration. This technique is a transformation algorithm, thus a signal can be transformed into its varying frequency contained in the seismic signal. There are a variety of spectral decomposition algorithms in the decomposing seismic signal from time domain into frequency domain. These algorithms include Short Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT). The STFT algorithm is a conventional and simple technique for computing a time-frequency spectrum, which is based on the application of Fourier transform. However, the STFT algorithm has a problem related to the frequency resolution. In its implementation, this algorithm is limited by predefi ned window length. In contrast, the CWT algorithm is believed to be able to overcome the limitation of window length. The CWT threats wavelet at certain window length, which is defi ned by the characteristics of the wavelet. In this study, the comparison between spectral decomposition technique based on STFT and CWT method was performed, particularly in its application to the synthetic and real data set. Each algorithm has its own advantages and disadvantages in decomposing the seismic signal. Further, this analysis can be used as a reference to select one of two algorithms for the specifi c application. The synthetic data set application shows that CWT algorithm produces better frequency resolution compared to STFT algorithm. In addition, the real data set application shows that time frequency section of the seismic line provides a spectral feature, which is useful to identify the hydrocarbon reservoir, which is associated with low-frequency shadow zone.
STRIKE-SLIP FAULT IDENTIFICATION BENEATH OF THE WIRIAGAR OIL FIELD Accep handyarso; H.M. Saleh H.M. Saleh
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.51

Abstract

The oil and gas explorations in the Eastern Indonesia is still lagging behind the Western Indonesia. The complexity of the geological structures and the geographical conditions caused Eastern Indonesia become virgin areas which commonly known as the frontier areas, such that the cost and risks of the oil and gas explorations become higher. Wiriagar Field is the only oil production fi eld in the Bintuni Basin with signifi cant production capacity. The search for new oil and gas location can use the analogy of the existing oil and gas fi elds. Thus the pattern of subsurface geological structures beneath the Wiriagar Field can be used as a template (key) in the search for new oil and gas fi eld in the Bintuni Basin. Analysis of the subsurface geological structures in the Wiriagar area conducted based on the gravity data with seismic and exploration well data as the constraints. There is an indication of the left-lateral strike-slip fault existence with SW-NE direction intersecting the anticline ridge with NW-SE alignment. The strike-slip fault then verifi ed through seismic section data. This structure pattern is suspected to infl uence the trap of the hydrocarbon which allows the migration from PreKais Formation to the Reservoir of Kais Formation beneath the Wiriagar Oil Field.
A LABORATORY STUDY OF CLAY SWELLING PROBLEM IN CO2 EOR BY CARBONIC ACID INJECTION IN CLAY SANDSTONE sugeng riyono; Aditya Pramada Wicaksono; Lutfi Andhika; Iqbal Fauzi; Billal Maydika Aslam; Rafael Purba; Handita Reksi; Hasian P. Septoratno Siregar
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.52

Abstract

Signifi cant portion of CO2 is dissolved in reservoir brine during CO2-Enhanced Oil Recovery. Dissolved CO2 forms an acidic environment which could modify rock-fluid interaction. One of the phenomena that could happen due to this interaction is clay swelling which may affect enhanced oil recovery performance. Several experiments were conducted in a number of sandstone core samples, i.e. Imbibition test, Core flood test, Conductivity test, and pH measurement. Imbibition test was conducted to evaluate CO2-saturated brine (approached with carbonic acid) performance toward oil recovery during five days measurement compared with brine imbibition performance. Moreover, core flood experiment was run to determine the effect of dissolved CO2 in brine on injection in sandstone. This is simulated by injecting brine (base case) followed by carbonic acid under 68.3OC. Thus, conductivity and pH of the imbibed fluids (before & after running imbibition test) were measured to justify occurrence of cation exchange. Interpretation of imbibition test indicated that imbibing carbonic acid, at pH value of about four, resulted in loss of oil recovery about 15% compared with brine due to formation damage, caused by clay swelling as sandstone contains clay. The existence of this phenomenon was confirmed by flow resistance at low pH in core sample which was higher than that in brine. This apparent plugging was expected due to severe clay swelling. Meanwhile, the existence of such phenomenon was also clarified with conductivity and pH measurement as there was a great amount of cation exchange. It can be inferred from this study that the rock-fluid interaction from CO2-saturated brine can result in adverse effect, such as injectivity problem and loss of recovery. This finding must be considered in planning CO2 EOR operations, especially when facing condition of watered out oil zone.
BIOCIDE SCREENING TEST TO PRODUCE WATER REINJECTION IN THE “X OIL FIELD” Zulkifliani Zulkifliani
Scientific Contributions Oil and Gas Vol 40 No 3 (2017)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.40.3.54

Abstract

Oil field produced water with a high fl ow rate usually contains suspended solid, such as corrosion, scale, bacteria, clay, wax, and oil residue. Biocide is used to reduce viability of bacteria cell in produced water reused for produced water reinjection into oil reservoir. The objectives of this study is to examine anti bacteria activity of fi ve active compound biocides i.e. Glutaraldehide (Biocide-1), Aldehyde-Based and Surfactants (Biocide-2), Glutaraldehyde, Quartenary Ammonium Compounds (Biocide-3), Tetrakis Phosphonium Hydroxymethyl Sulfate (Biocide-4), and Amine Aldehide (Biocide-5) for reduced bacteria cell in produced water in this fi eld. Resulted in this study is general aerobic bacteria group is high contamination at the produced water reinjection. Bacteria isolates identifi ed is Bacillus sp (2 types of isolates) and Pseudomonas alcaligenes. The type of Biocides-2 and Biocide-3 reduced the number of bacteria cells maximal at a concentration of 200 ppm.Oil field produced water with a high fl ow rate usually contains suspended solid, such as corrosion,scale, bacteria, clay, wax, and oil residue. Biocide is used to reduce viability of bacteria cell in producedwater reused for produced water reinjection into oil reservoir. The objectives of this study is to examineanti bacteria activity of fi ve active compound biocides i.e. Glutaraldehide (Biocide-1), Aldehyde-Basedand Surfactants (Biocide-2), Glutaraldehyde, Quartenary Ammonium Compounds (Biocide-3), TetrakisPhosphonium Hydroxymethyl Sulfate (Biocide-4), and Amine Aldehide (Biocide-5) for reduced bacteriacell in produced water in this fi eld. Resulted in this study is general aerobic bacteria group is highcontamination at the produced water reinjection. Bacteria isolates identifi ed is Bacillus sp (2 types ofisolates) and Pseudomonas alcaligenes. The type of Biocides-2 and Biocide-3 reduced the number ofbacteria cells maximal at a concentration of 200 ppm.
A CUSTOMIZED QUASI THREE-PHASE DRAINAGE RELATIVE PERMEABILITY MODEL FOR SOME INDONESIAN WATER-WET SANDSTONES Prof. Dr. Ir. Bambang Widarsono, M.Sc.
Scientific Contributions Oil and Gas Vol 41 No 1 (2018)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.41.1.61

Abstract

Information about drainage effective two-phase – i.e. quasi three-phase – relative permeability characteristics of reservoir rocks is regarded as very important in hydrocarbon reservoir modeling. The data governs various processes in reservoir such as gas cap expansion, solution gas expansion, and immiscible gas drive in enhanced oil recovery (EOR). The processes are mechanisms in reservoir that in the end determines reserves and resevoir production performance. Nevertheless, the required information is often unavailable for various reasons. This study attempts to provide solution through customizing an existing drainage relative permeability model enabling it to work for Indonesian reservoir rocks. The standard and simple Corey et al. relative permeability model is used to model 32 water-wet sandstones taken from 5 oil wells. The sandstones represent three groups of conglomeratic sandstones, micaceous-argillaceous sandstones, and hard sandstones. Special correlations of permeability – irreducible water saturation and permeability ratio – irreducible water saturation have also been established. Model applications on the 32 sandstones have yielded specific pore size distribution index (λ) and wetting phase saturation parameter (Sm) values for the three sandstone groups, and established a practical procedure for generating drainage quasi three-phase relative permeability curves in absence of laboratory direct measurement data. Other findings such as relations between λ and permeability and influence of sample size in the modeling are also made.
DRY CLIMATE EXPANSION ON THE PLEISTOCENE OF INDONESIA AS RECORDED IN ITS POLLEN ASSEMBLAGE Eko Budi Lelono
Scientific Contributions Oil and Gas Vol 41 No 1 (2018)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.41.1.69

Abstract

Most researchers agree that Pleistocene is characterised by glacial and inter glacial periods which are strongly related to dry/ cool and wet/ warm climates. Apparently these are refl ected on their pollen records. The period of dry climate (glacial climate) is characterised by abundant Gramineae pollen, whilst the period of wetter climate (interglacial climate) is indicated by an increase of coastal and mangrove palynomorphs, but greatly reduced frequencies of Gramineae pollen. On the contrary, previous works on the Pleistocene sediments of Java indicated high abundance of grass pollen along this age marking drier climate condition. This paper publishes the study which is intended to evaluate paleoclimate of Java and other area of Indonesia during Pleistocene. For this purpose, some well samples from East Java and Papua were collected. Standar laboratory preparation was employed to extract pollen from the cutting samples. This study applies quantitative method which allows detail climate change interpretation. This study shows that Pleistocene of East Java is characterised by abundant grass pollen of Monoporites annulatus which may correspond to the period of expansion of savanna vegetation coinciding with glacial period. More over, it is indicated by abundant charred Gramineae cuticles which derive from burning grass. This might have been caused by extreme heat which could relate to the volcanic activities existed in East Java. Slightly different record appears in Papua which shows repetition of dry/ wet condition or low/ high sea level. The moist climate related to the phase of sea level rise is marked by abundant brackish pollen which possibly represented interglacial period. It is also supported by the increase of peat swamp and freshwater palynomorphs. On the other hand, dry climate representing glacial period is defined by significant decrease of these brackish and freshwater elements.
ASP INJECTIVITY ANALYSIS AS PREPARATION FOR FIELD IMPLEMENTATION Sugihardjo Sugihardjo
Scientific Contributions Oil and Gas Vol 41 No 1 (2018)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.41.1.70

Abstract

This laboratory experiment is a highlight of the preparation of ASP (Alkaline-Surfactant-Polymer Mixture) chemical injection for field implementation to determine the injectivity parameter and the effect of fluid properties change during flow into the porous media. Therefore, the experiments were focus on injectivity which is represented by permeability change. Besides, IFT and viscosity reduction, and also adsorption of injected chemical on the surface of pore throat were also investigated. ASP chemical solution has been prepared for experiments, the mixture consists of 0.3% of Surfactant-A, 1000 ppm Polymer KP and 0.2% alkaline of NaOH. This mixture has been evaluated the bulk properties for instance: IFT, viscosity and other parameter such as: compatibility, thermal stability, phase behavior, and filtration that are suitable for enhanced oil recovery for the target oil field. The next step is to examine the interaction between rock and injected fluid that may change the fluid and rock properties. ASP injection in carbonate rock in this experiment may result in permeability damage and almost totally block the pore throat. Reduction of permeability is very significantly approaching the value of PRF of level 88.76%. The damage could not be revocable after post flush of water that is indicated that the permeability reduction is permanent. Fluid properties of the ASP including IFT and viscosity show that the IFT looks constant and no signifycant change, on the hand the viscosity of the fluid drops down to almost 32.6% from the original. However, the adsorptions are still categorized as normal.
SIMULTANEOUS MEASUREMENT OF SYN-GAS COMPONENT (H2, CO2, CH4, AND CO) AS PRODUCT OF BIOMASS GASIFICATION BY USING VALIDATED GC-TCD METHOD Muhammad Rizky Mulyana; Oman Zuas; Harry Budiman; Sabar Simanungkalit; Nino Rinaldi
Scientific Contributions Oil and Gas Vol 41 No 1 (2018)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.41.1.73

Abstract

Biomass gasification has been widely known method to produce syn-gases, which can be considered as great alternative substitution for fossil fuels. However, accurate verification of the syn-gas composition requires a reliable and validated method for simultaneous measurement of H2, CO2, CH4, and CO. In order to fulfill the aforementioned requirements, which is the objective of this study; a GC-TCD method for simultaneous measurement of H2, CO2, CH4, and CO component in syn-gas has been validated in accordance to ISO/IEC 17025 and its application for real samples. For the method validation purpose, all of the performance parameters were evaluated and discussed in detail in this study. Intraday precision and interday precision were found to be acceptable having the %RSD below 0.67xCV Horwitz and below 1.0xCV Horwitz, respectively. The bias value falls within +2σ for entire components, indicating that the method accuracy can be accepted. Coefficient correlation for all components was higher than 0.99, which means that the method has suffi cient linearity. LoD and LoQ for each component were found to be lower than typical syn-gas concentration range. The method roughness was also found in an acceptable level (the p-values was higher than 0.05 for allctarget components. Application of the validated method for the measurement of a real syn-gas samples indicated that the method is quite reliable to produce an accurate data and the validated methid can be used in a routine analysis. The innovation of this study, as shown by experiment results, is to evaluate the validated method’s performance for simultaneous determination of syn-gas components’ concentration in one channel, compared to common method in which the syn-gas components were measured separatedly in a different channel.Biomass gasifi cation has been widely known method to produce syn-gases, which can be consideredas great alternative substitution for fossil fuels. However, accurate verifi cation of the syn-gas compositionrequires a reliable and validated method for simultaneous measurement of H2, CO2, CH4, and CO. Inorder to fulfi ll the aforementioned requirements, which is the objective of this study; a GC-TCD methodfor simultaneous measurement of H2, CO2, CH4, and CO component in syn-gas has been validated inaccordance to ISO/IEC 17025 and its application for real samples. For the method validation purpose,all of the performance parameters were evaluated and discussed in detail in this study. Intraday precisionand interday precision were found to be acceptable having the %RSD below 0.67xCV Horwitz and below1.0xCV Horwitz, respectively. The bias value falls within +2σ for entire components, indicating that themethod accuracy can be accepted. Coeffi cient correlation for all components was higher than 0.99, whichmeans that the method has suffi cient linearity. LoD and LoQ for each component were found to be lowerthan typical syn-gas concentration range. The method roughness was also found in an acceptable level(the p-values was higher than 0.05 for allctarget components. Application of the validated method for themeasurement of a real syn-gas samples indicated that the method is quite reliable to produce an accuratedata and the validated methid can be used in a routine analysis. The innovation of this study, as shown byexperiment results, is to evaluate the validated method’s performance for simultaneous determination ofsyn-gas components’ concentration in one channel, compared to common method in which the syn-gascomponents were measured separatedly in a different channel.Keywords: syn-gas, GC-TCD, method validation.

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