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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
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METHOD OF LABORATORY ANALYSIS FOR OIL SHALE ASSAY Herlan Adim
Scientific Contributions Oil and Gas Vol 27 No 1 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.1.1047

Abstract

Oil shale is much commoner than is generally realized, occuring on every continent and in every geological system. They are misnamed, but it is unlikely that any more appropriate name will be acceptable either to geologists. Few important deposits actually consist of shales and even fewer have yielded any oil. In the conventional sense most "oil shale" is actually bituminous, nonmarine limestones or marlstones containing kerogen. Only a few marine examples can be properly described as shales. The common composition involves about 50 percent of mineral carbonates by weight. A variety of silicates may also be present, possibly derived from the reaction of circulating alkaline waters with volcanic debris.
CALCIUM SULFATE SCALE IN THE PETROLEUM INDUSTRY Hadi Poernomo; Tjuwati Makmur
Scientific Contributions Oil and Gas Vol 27 No 1 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.1.1048

Abstract

Oilfield scale is defined as the precipitation of hard, adherent deposits of inorganic solid originating from aqueous media. This constitutes sulfate and carbonate of the alkaline earth metals calcium, barium and strontium and complex salts of iron. Generally, the process of the scale deposition occurs when the product solubility of a compound considered is exceeded. The formation of scale, such as calcium sulfate, has long recognised as one of the serious problems in oil and gas production leading to reduced production rates as flow becomes restricted. Calcium sulfate scale found in the oilfield is in the form of gypsum (CaSO4, 2H2,0) which is the most stable form at temperatures of 40 °C or less at atmosphere pressure. Above this temperature, anhydrite (CaSO4,) may be found, although hemihydrate (CaSO. 1/2H,O) may form under certain conditions. The reaction for precipitation of calcium sulfate is as follows: Ca+2 (aq) + so4-2 (aq) = CaSO4 (solid) The solubility of calcium sulfate in distilled water is 2080 mg/l at 25 "C. Calcium sulfate scale arises from several causes, such as temperature, dissolved salts, pressure, and time. The main points of this paper are focused on nomenclature, chemical structure, the occurrence of calcium sulfate scale, example of calcium sulfate scale in the petroleum industry, and calculation of calcium sulfate solubility in brine.
PALYNOLOGICAL EVENTS OF THE TALANG AKAR FORMATION IN THE ON-SHORE AREA OF THE SOUTH SUMATRA BASIN Eko Budi Lelono
Scientific Contributions Oil and Gas Vol 27 No 2 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.2.1049

Abstract

South Sumatra has been well known as the one of the largest hydrocarbon producers in Indonesia. Due to its potentiality, South Sumatra has been explored since the Dutch era. Million barrels of oil have been pumped out from this area and many unpublished reports and papers have been made regarding the remaining reserve of this area. This study focuses on Talang Akar Formation which is considered as the main reservoir in South Sumatra. Talang Akar Formation is interpreted to be formed in a deltaic environment (De Coster, 1974). The deltaic sediment must have contained excellent palynomorph assemblage as demonstrated by the previous authors (Hasjim, 1993, Morley, 1995 and LEMIGAS 2001a, b and c). On the other hand, marine microfossils show poor recovery including foraminifers and nannoplankton. This condition is understandable as marine microfossils are difficult to develop in the transition environment. For this reason, palynology is intensively studied as a powerful tool to comprehend the stratigraphy of the Talang Akar Formation.The deposition of Talang Akar Formation was influenced by the tectonic event during Late Cretaceous to Early Tertiary which caused the occurrence of Semangko Dextral Fault (Suwidiyanto, 2003). This fault resulted in the formation of horst and graben which allowed sedimentation of Lahat Formation and the Lower Talang Akar Formation in the low topography. Subsequently, sea level increased rapidly drowning up the deposition center which resulted in the sedimentation of the Upper Talang Akar Formation and limestone Baturaja Formation (Suwidiyanto, 2003). Based on lithological character, Talang Akar Formation is separated into Great Sand Member (GRM) occupying lower part of this formation and Transition Member (TRM) situating in the upper formation. GRM was formed in the fluvial to delta plain environment, whilst TRM was deposited in delta plain to pro-delta environment (De Coster, 1974). The environmental change from fluvial-delta plain of GRM (non-marine) to delta plain-prodelta of TRM (nonmarine to transition) suggests the occurrence of transgressive phase. Palynologically, this change must be reflected in the palynological assemblage. In fact, TRM yields more brackish palynomorphs than those of GRM. In contrary, GRM especially those of river channel deposits are characterised by regular occurrence of riparian (freshwater) pollen such as Marginipollis concinus and Pandaniidites sp. (LEMIGAS, 2001a, b and c).Although palynological investigations were frequently conducted within the Talang Akar Formation, the results of these investigations were restricted on age interpretation and paleoenvironment analysis. There are more information can be obtained from the palynological data. Therefore, it is required extra efforts to elaborate data becoming useful information such as palynological event, sea level changes and paleoclimate. This study intends to explore the stratigraphy of the Talang Akar Formation based on its palynological and other micro-fossil content which focuses on palynological characteristic of the Talang Akar Formation, palynological event and other biostratigraphic information (zones, age and depositional environment).
ENVIRONMENTAL AND REGULATORY ASPECT STUDY ON THE HARBOR EXTENSION DEVELOPMENT OF PETROLEUM AND PETROCHEMICAL INDUSTRIES Desrina Desrina
Scientific Contributions Oil and Gas Vol 27 No 2 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.2.1050

Abstract

Petroleum and petrochemical industries are those industries involving huge amount of products that shall be transported across regional and even international boundaries. Accordingly, many of these industries have their own special harbor or port to accommodate ships that are in and out of the harbor for the purpose of transporting their products. Industries having their own harbor for example are, among others, Pupuk Kalimantan Timur (PKT) in East Kalimantan that produces Ammonia and Urea, and Pertamina Cilacap in Central Java that produces fuels.As general harbor facilities that need maintenance, this special port has also to be maintained and sometimes extended due to the needs for accommodating bigger ships. Maintenance dredging is one of a harbor maintenance programs for keeping the berth that is always suitable for the ships. When the production of the industries has to be expanded for example due to demand for export purposes, the harbor that supports this activity has also to be extended. Some harbors even need a new area for developing harbor extension, because the old one is not sufficient for accommodating bigger ships.The harbor extension development will involve several activities, namely (i) dredging of the coastal sediments, (ii) coastal reclamation with the use of some of the dredged materials, (iii) dumping of the dredged materials, and (iv) development of ship-waste reception facilities. Every phase in the harbor extension activity will undoubtedly impact in some extents to the environment surrounding the project. The potential impacts of the project to the environment will depend on the scale (area and volume) of each phase and the duration of the activities. The Ministerial Decree of Environment No. 17/20011 describes the scale limit of the project that has to be preceded by the environmental impact analysis (EIA), or AMDAL study in order to get governmental permit before the project can be implemented. This is certainly valid for a new project that its environmental area has not been studied yet.Generally, many of the petroleum and petrochemical industries have been established long before the No.17/ 2001 decree being put into effect. The area of the port extension project in which this study was conducted is located in the area that has been studied through Environmental Evaluation Study, SEL (Studi Evaluasi Lingkungan) 2 . Basically, this environmental study covers all over the sphere that has been intended for the industrial activity. There are questions that may arise concerning with the extension project in this area. Should EIA/AMDAL study be conducted for this extension project? Is UKL/UPL (Environmental Management Effort/Environmental Monitoring Effort) study sufficient for this purpose? Regarding that the project scale may exceed the scale limit as described in the No. 17/2001 decree, shall RKL/RPL (Rencana Pengelolaan Lingkungan/Rencana Pemantauan Lingkungan) – Environmental Management Plan/Environmental Monitoring Plan – be revised?For the purpose of harbor extension, beside the feasibility study which has been covered in the Master Plan Document, it is worthy to describe an environmental review and consideration regarding the activities that might result in an impact to the project surroundings. This environmental review that can be considered as an environmental rapid assessment is beneficial for the project management to have knowledge in making a decision concerning with the selection which the environmental studies (AMDAL, RKL/RPL, or UKL/UPL) that should be conducted prior the implementation of the project.This paper describes a study that has been conducted concerning the port extension of the petrochemical industry in East Kalimantan, where the SEL for that area has been established. The study emphasizes on the discussions on the environmental and regulatory aspects, in order to have background knowledge leading to the detail environmental management and monitoring study that shall be conducted prior the implementation of the project. The review is divided into two basic issues, namely dredging activity and ship-waste reception facilities. Due to related issues in dredging activities, review concerning dredging, coastal reclamation and dredged material dumping are grouped into one paragraph, while those of shipwaste reception facilities in other paragraph.
INVESTIGATIONS ON THE STORAGE EFFICIENCY OF CO2 IN CARBONATE AQUIFERS Sugihardjo Sugihardjo
Scientific Contributions Oil and Gas Vol 27 No 2 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.2.1051

Abstract

The production of associated and nonassociated gas increases due to additional new oil and gas fields. Consequently, there will be an increase of CO2 released from associated gas, and especially, from nonassociated gas. Actually, CO2 may still be utilized in an attempt of increasing oil recovery through the methods of EOR (Enhanced Oil Recovery) or IOR (Improved Oil Recovery). In general, on the one hand, the CO2 availability in the atmosphere is still be needed for the photosynthesis process. But, on the other hand, this gas can stimulate the greenhouse effect that influences the global warming and weather changes. Prior being utilized, CO2 can be stored first in the depleted oil reservoirs or in the aquifers. The feasibility of these reservoirs or aquifers as a CO2 storage can be determined through the mechanisms of CO2 /water injection, or CO2 solubility in the water. For the purpose of several experiments, specific characters of the cores and formation water were decided taken from a representative carbonate reef formation in West Java region to substitute the samples from Natuna Field. The experiments were then continued on studying the CO2 solubility in the formation water not only at constant volume but also with varied volume, and also the CO2 storage efficiency in the carbonate rocks saturated with water.
THE MANAGEMENT OF SPENT CATALYST OF HYDROCONVERSION PROCESSES IN ASEAN REFINERIES A.S. Nasution; E. Jasjfi
Scientific Contributions Oil and Gas Vol 27 No 2 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.2.1052

Abstract

Catalytic processing is a keystone of today’s petroleum refining. The catalytic processes applied in the potreleum industry are generally large scale. In today’s operating climate of increased attentiveness toward environmental and safety issues, spent catalyst management options have became an important consideration for refiners. A catalyst deactivation determines how it can be handled after it is discharged from the processing unit. The type of the catalyst and its condition (whether it is considered hazardous) often determines the disposal route selected. Because of the self-heating and leaching problems associated with spent hydrotreating catalyst,it is recommended that refiners ship their spent catalysts to what is called “true recycles”. The U.S. Environmental Protection Agency (EPA), for example, is in the process of reevaluating the designation of spent hydroprocessing catalyst as an hazardous waste. Out of 3,837 MBPSD total crude oil currently processed in ASEAN (Brunai Darussalam, Indonesia, Malaysia, Philippenes, Singapore, Thailand, not including Vietnam, Laos and Myanmar) arround 61 percent volume is passed through catalytic processes (included hydroconversion processes 58 vol.%) to produce various fuel components such as gasoline and diesel oil. These hydroconversion processes use about 3,279 tons of catalyst with about 28 tons per day of spent catalyst. The present paper discusses briefly a survey on the management of spent catalyst of hydroconverion processes in ASEAN refineries and some aspects of catalyst poisoning of major hydroconversion processes in petroleum refinery. A survey on the management of spent catalyst from hydroconversion processes in ASEAN refineries is described in this paper.
TEST OF FORMATION WATER AND CHEMICAL COMPATIBILITY FOR REMOVAL OF MUDCAKE IN WELLBORE Panca Wahyudi; Tjuwati Makmur
Scientific Contributions Oil and Gas Vol 27 No 3 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.3.1054

Abstract

Laboratory and field studies indicate that almost every operation in the field, such as drilling, completion, workover, production and stimulation are potential source of damage to well productivity. Formation damage has long been recognized as a source of serious productivity reduction in many oil and gas reservoirs. The mud cake is a damage that occurs in formation caused by drilling process. Prevention of formation damage has the following advantages : a) To reduce ultimate completion costs; b) To preserve barriers; c) To improve sweep efficiency. Potassium chloride (KCI) and breaker are chemical materials used in mud clean up system to remove the mud cake formed in drilling process. In relation to this, it is very important to know whether the formation water and KCI solution, then the formation water and breaker, are compatible or not. This paper is written based on our experience in formation damage laboratory tests. Therefore, the main topic of this paper is "Test of Formation Water and Chemical Compatibility for Removal of Mudcake in Wellbore ". Hopefully, the laboratory test results presented in this paper are valuable, not only for LEMIGAS as Research and Development Centre For Oil and Gas Technology, but also for oil companies as the user which will apply the chemical material in oil fields (cost efficiency), chemical material supplier (particularly in design of breaker).
THE APPLICATION OF REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM FOR OIL AND GAS PIPELINE ROUTE PLAN Suliantara Suliantara
Scientific Contributions Oil and Gas Vol 27 No 3 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.3.1055

Abstract

The application of the remote sensing and geographic information system was widely used in the oil and gas industry in Indonesia. These technologies have been recognized as a support/tool on both upstream to downstream, from geologic information extraction, logistic support to various activities of environment. Remote Sensing (RS) is defined as the science and technology by which the characteristic of the objects of interest can be identified, measured or analyzed without direct con- tact. Aircraft and satellite are common platform from which remote sensing observation are made. The term RS is restricted to method that employ electromagnetic energy as the means of detecting and measuring target characteristic (Figure 1). Geographic Information System (GIS) is actually unique system because it will man- age both spatial and attribute data in one-reference entities (Figure 2). Spatial data is the kind of data that refer to certain geographic domain, or geoinformation and usually display as thematic map. Attribute data refer to non-thematic map, such as table or other data- base. In general, the oil and gas activity is divided into two parts, i.e.: upstream and downstream activity or on the exploration and production phase. On the production phase, the hydrocarbon is transported from production well to gathering station, refinery plant and or export facilities. Pipeline is one way to connect oil and gas activities in oil and gas transportation. In Indonesia oil and gas fields are located at various physiographics, that vary from tropical forest to offshore area. So, they needs certain tool that can gather the earth surface condition efficiently. Remote Sensing and GIS technology offer a capability to support such needed. The capability of this technology is increasing in recording earth surface condition spatially and data variety. The case studied lay between Merbau to Pagardewa, South Sumatera, generally covered by forest, rubber plantation, villages and local residences, limited road network and geologically dominated by Tertiary and Quaternary sediments. Remote sensing of medium spatial resolution was applied to gather the earth surface situation. GIS technology was applied to manage all data that have been collected.
THE PALEOGENE SEDIMENT IN SOUTH SUMATRA - WHERE HAS IT GONE? Eko Budi Lelono
Scientific Contributions Oil and Gas Vol 27 No 3 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.3.1056

Abstract

It has been widely known that South Sumatra Basin yields Paleogene successions (Ferdiyanto et al., 2003). These successions consist of Lemat and Talang Akar Formations (De Coster, 1974) or Lahat and Lower Talang Akar Formations (Clure et al., 2002). The regional stratigraphy of the South Sumatra Basin is shown in Figure 1. The Paleogene sediment is interpreted to form within the occurrence of horst and graben which was caused by the formation of Semangko dextral fault as a result of Late Cretaceous-Early Tertiary tectonism (Suwidiyanto, 2003). In its study, LEMIGAS (2001) classified these successions as the synrift deposit because they were deposited during rifting phase which presumably occurred in Oligo-Miocene age. In fact, finding the Paleogene synrift sediment in South Sumatra is a serious matter. Most studied wells provided by the client lacks biostratigraphic evidences of Paleogene age. The author contributed to this study by investigating the fossil contents of the studied sediment. The result of the biostratigraphic analysis of this sediment encourages the author to publish it as presented in this paper. Therefore, this paper is intended to disclose a comprehensive biostratigraphic data which is obtained from three different disciplines including foraminifer, nannoplankton and palynology. The Early Tertiary sediment in South Sumatra was generally deposited in the non-marine to transition (deltaic) environment (De Coster, 1973). The previous investigators show that this type of sediment contains rich palynomorph (Hasjim, 1993, Morley, 1995 and Lelono, 2003). Apparently, the age determination mostly referred to the occurrence of age diagnostic pollen. In this case, the appearance of peat swamp element of Meyeripollis naharkotensis is used to indicate the Oligocene sedi- ment (LEMIGAS, 1998). Unfortunately, it was lack of support from other microfossil study such as foraminifer and nannoplankton which resulted in least confidence to this interpretation. The occurrence of M. naharkotensis has been widely used to designate the Late Paleogene over the Southeast Asian Region (Morley, 1991 and Rahardjo et al., 1994). However, the stratigraphic range of M. naharkotensis is somewhat ambiguous as this pollen associates with the occurrence of coals indicating the ever-wet warm climate (Morley, 1991). In fact, this pollen ranges up as far as basal Late Miocene as recorded in the coaly succession of East Kalimantan (Lelono, 2003). On the other hand, in East Java, well section with least coal development shows the distribution of M. naharkotensis along the Oligocene section (Lelono, 2003). Nichols (1999) stated that the age indicators strongly controlled by facies reduce their stratigraphic value. This means that the occurrence of M. naharkotensis does not necessarily indicate the Late Paleogene. Therefore, it is suggested to consider the existence of coal lithology in applying M. naharkotensis for age interpretation. The occurrence of (?Late Oligocene)-Early Miocene rift sediments led to the conclusion that the rifting phase triggered by Late Cretaceous-Early Tertiary tectonism occurred slightly later in South Sumatra than that in Central Sumatra (LEMIGAS, 2001). Meanwhile, In Central Sumatra, rift deposit occurred during Eocene-Oligocene time (Williams et al., 1985 and Longley et al., 1990). Although De Coster (1974) assumed that South and Central Sumatra Basins had very similar and related history and could be considered as one large basin with many troughs and grabens, the recent biostratigraphic data suggest distinct period of basin development between South and Central Sumatra. This interpretation may not be obtained without accurate biostratigraphic data. Therefore, this paper is published to provide biostratigraphic information which allows explorationists to possess better understanding of the South Sumatra Basin.
THE APPLICATION OF THE 't' TEST AND MARKOV CHAIN ANALYSIS IN BIOSTRATIGRAPHY OF 'X' WELL Panuju Panuju; Mufdi Firdaus
Scientific Contributions Oil and Gas Vol 27 No 3 (2004)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.27.3.1057

Abstract

There is no habit in biostratigraphers to apply the statistic methods to solve problems in their jobs, whereas in fact these methods are very useful when conventional ways failed. The use of this method has become very important in reservoir scale where microfossil content is low and indicator species is rare or absent. Applying biozonation in reservoir scale is much less reliable since reservoir layers are mostly below zonal resolution, so that the application of high resolution biostratigraphy is needed. In this case, the integration of biometric study and 't' or 'f' test can be used to define bioevent precisely. In sequence stratigraphy, data of depositional environment in various system tracts that determined using microfossil assemblage are very important. However, for the reasons of barren or no samples, this information might not be obtained by biostratigraphy or other methods. Due to the geological cycle and repeatable nature of depositional sequence, Markov Chain analysis can be used to predict the lost information about environment of deposition.

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