The Implementation of Critical Gas Rate in Liquid Loading Well and Optimization Analysis using the Adequacy Chart

In the gas well, liquid loading occurs when the gas rate is insufficient to lift liquids into the surface such as water and/or condensate. This causes an accumulation of the liquid in the wellbore, supplies additional backpressure to the formation, and may completely kill the well. Meanwhile, the limited space and typically high cost of offshore operations have made a proper study for optimization selection very essential. The selected project must fulfill several requirements, namely: 1) Fit for the purpose, 2) Low risk and uncertainties, and 3) Economic. Hence, this study will describe the pilot project and continuous improvement process of lowering the gas well pressure using a wellhead compressor and a temporary separator to optimize the liquid loading. It also explains the implementation of critical gas rate in predicting the liquid loading event from the well’s production history. A new analysis method utilizing the adequacy chart was proposed to verify the suitability of the available pressure-lowering system unit available in the market with the well candidates. An adequacy chart was constructed from the well’s deliverability, critical gas rate, and lowering pressure unit or system capacity. These three charts will combine to generate an overlapping area, which signifies suitability for the recommended operation. The well’s production data history can be used to predict the liquid loaded-up event due to the continued decline of the generated gas. Also, a combination of the critical gas rate and decline analyses can predict potential liquid loading problems.

A Study of The Design Method and Similitude for A Small-Scale Test Drilling Rig (Part 1): An Application of The Geometrically Distorted Scaled Modeling Method

Drillstrings often vibrate severely and tend to twist off during hard rock drilling. Therefore, dynamic testing is crucial in the design of drilling systems. Designers tend to employ the most powerful analytical tools, using the most elaborate electronic computers, however, actual testing is required to the designed system function optimally. In cases of enormous drilling systems, complex dynamic tests are often performed on a smaller-scale replica of the system, referred to as the model, which is more convenient, cost-effective, and time-effective. This study, therefore, describes the establishment of similar conditions among structural systems, with the main objective of studying the similitude theory’s applicability in establishing the necessary similar conditions for designing scaled-down models to predict the drillstring’s vibration behavior. The scaling laws for all the relevant parameters regarding the scaled drillstring model, as well as the full-size drillstring system, were derived from the respective equations of motion. The scaling factors for all relevant parameters are determined using the theory of dimensional analysis. In addition, the geometry distorted similitude theory is revisited and employed to overcome the physical limitation and develop the necessary similar conditions for dynamic testing of the scaled drillstring. Meanwhile, the similitude relationship between the prototype and the model was validated with a case study using lumped segments bond graph modeling and simulation software.

Study of Indonesia’s Solar Energy Implementation Using Identification of Potency, Policies, and Cost-Benefit Analysis

The solar PV systems are semiconductor devices that precisely convert sunlight into electricity, through the transfer of electrons. They provide several advantages, such as high modularity, zero noise, and adequate availability of solar resources in Indonesia. Therefore, this study aims to determine the potency, policy perspective, and Cost-Benefit Analysis (CBA) of the solar energy implementation for electricity generation. A statistical analysis was used for measuring potency, as well as reviewing opportunistic policies and barriers. A review of some CBA-based journals was also carried out, to determine that the development of solar power electricity had more benefit than fossil fuels and LCOE (Levelized Cost Of Electricity). The results of the 10-days average value calculation in 2019 were 388-563 W/m2, with the maximum values at 1137-1604 W/m2. Meanwhile the analysis of the maximum hourly averages for Western, Central, and Eastern Indonesia were 570-719, 634-758, and 559-627 W/m2 at 11.00-12.00 WIB, 11.00-13.00 WITA, and 12.00-13.00 WIT, respectively. The potency of solar radiation intensity in Indonesia was averagely 150-750 W/m2, as the highest values were found in East Nusa Tenggara, Maluku, and Merauke.

Techno-Economic Analysis of Hydraulic Fracturing As A Solution for Developing Low-Resistivity and Low-Quality Zone on Offshore “RI” Field

Hydrocarbon production in Indonesia is continuously decreasing on a yearly basis, which is in contrast with its increasing level of consumption. Low-quality and low-resistivity reservoir zones are deemed to possess a lot of hydrocarbon potentials, however, little priority has been placed on their development due to their small level of production. The "RI" field that was utilized in this study is a mature offshore field with a reservoir which has a low-quality and low-resistivity zone. This area has been in use for more than thirty years, therefore its rate of oil production has declined. This study aims to review the techno-economic aspects of well stimulation in the form of hydraulic fracturing. And also, to determine the development method that is suitable for low-quality fields. The hydraulic fracturing process was modelled using Fracpro software as input parameters for the reservoir production simulations. The reservoir behavior was simulated using the CMG software to observe the amount of hydrocarbon liable for production in various development scenarios. Three cases were performed on the "RI" field, which was stimulated for ten years of operation. The first case was the instance with the natural flow, while the second implemented hydraulic fracturing at the beginning of production, and the third was the implementation of hydraulic fracturing, which started in the middle of the production period. Then, the three cases are evaluated utilizing a Gross Split scheme, to calculate the economics of the project both from the government and contractor's aspects. The simulation study concluded that fracturing at the beginning of the LRLC zone development is the most profitable. The novelty of this study is the comparison of scenarios for the implementation of hydraulic fracturing methods in fields with low-resistivity and low-quality zone whose economic value is evaluated by the Gross Split scheme.

Indonesia Well Abandonment Standard Gap Analysis; A Review and Suggestion

The old oil and gas wells of approximately 70% are found to have no economic value in Indonesia, leading to being abandoned during the end of their lifecycle, as ruled by the government. This is part of decommissioning an entire field with an environmental preservation program, known as an Abandonment and Site Restoration (ASR). The program involves the evaluation of international permanent abandonment standards, as references for the designs, comparisons, and assessments of Indonesia’s policies. It also provides contrast gap analysis and suggestions in ensuring a proper permanent plug and abandonment approach, to avoid any future leaks or re-abandonment operations. Therefore, this study aims to determine and evaluate the gap analysis between Indonesia and International Well Abandonment Standards, as well as OGUK and NORSOK D-010. The results showed that abandonment activities had improvement opportunities philosophy, and practice, used for plugging/isolations, control lines, as well as reservoir and annular barriers. In addition, literature studies were performed to understand the abandonment philosophy for all reviewed standards, to provide proper suggestions or improvements.

An Integrated Survey of the Geochemical Study at the Blawan-Ijen Area, East Java

Geothermal energy is a renewable alternative energy source. One of the analyses used to determine the characteristics of a geothermal field is water geochemical analysis. The target of this research is the Blawan-Ijen geothermal prospect area, Bondowoso. The geochemical analysis was carried out using AAS, Spectrophotometer and acid-base titration. This survey shows the characteristics of the geothermal system and geothermal fluid in the Blawan area, Ijen. From the chemical analysis of hot water, we found that the types of geothermal water fluids in the Blawan Ijen area vary. In samples BL1, BL2 and BL5 included in the type of Sulphate Water with the dominant elemental Sulphate (SO4) content is also known as Sulfuric Acid Water (Acid-Sulphate Water). Then for the BL4 sample included in the type of chloride water. This type of water is a type of geothermal fluid found in most areas with high-temperature systems. Areas with large-scale hot springs flowing with high Cl concentrations originate from deep reservoirs and indicate permeable zones in those areas. However, this area may not be located above the main upflow zone. There are several other possibilities, such as topographic influences, which can significantly impact hydrological control. The presence of chlorine gas can also identify high zones' permeable areas (e.g., faults, breccia eruptions or conduit). In contrast, BL3 samples are included in the Bicarbonate Water-type. The element HCO3 (bicarbonate) is the most dominant element (main anion) and contains CO2 gas from the chemical analysis results. HCO3 water is generally formed in marginal and near-surface areas in systems dominated by volcanic rocks, where CO2 gas and condensed water vapour into groundwater. The vapour condensation can either heat the groundwater or be heated by steam (steam heated) to form an HCO3 solution

Application of Empty Oil Palm Bunches as CMC to Prevent Loss Circulation

Drilling is an activity carried out to obtain the desired target. Furthermore, drilling mud a very significant material involved in the drilling process, and must, therefore, obtain a rational value from the rheology. A suitable technique to achieve this goal is the use of additives, for instance, Carboxymethyl Cellulose (CMC) to improve the viscosity and air binding. This study, therefore, uses CMC produced from organic oil palm bunches as an alternative for industrial CMC. CMC of Oil Palm Empty Bunches have been tested by Energy Dispersive X-ray Spectroscopy (EDS) to determine its composition. The Empty Oil Palm Oil which uses Tenera type was taken from Riau Province, Rokan Hulu Regency, Kunto Darussalam District. In this study, this experiment used CMC Empty Oil Palm and industrial CMC to find the value of viscosity, plastic thickness, melting point, gel strength, mud cake, and filtering volume of drilling mud and prevent the loss circulation with adding each CMC composition to mud samples with amount of 2 gr, 4 gr, 6 gr, 8 gr and 10 gr. According to the EDS analysis, the Carbon (C) and Oxygen (O) content of CMC from empty oil palm bunches were 58.85% and 41.15%, respectively. In addition, the industrial standard for plastic viscosity and yield point were not attained by using 8 gr and 10 gr of this CMC.

Completion Design for The Development of a Multi-Layer and Multi Fluid Reservoir Systemin Offshore Well AA-01, North-West Java

Completion systems are important components of hydrocarbon field development. As the link between the reservoir and surface facilities, completions need to be designed to maximize hydrocarbon recovery and withstand consistently changing conditions for years, within the safety requirements. However, designing completion for a well comprising a multi-layer and multi-fluid reservoir is quite challenging. The completion design must use the right materials and be able to safely produce single, as well as commingle products, and add any artificial lifts, depending on the method with the most optimum value. This paper, therefore, discusses the model development of completion design for an offshore well AA-01, one of the offshore wells with multi-layer and multi-fluid reservoir systems in Indonesia. Well AA-01 penetrates two productive layers, the upper layer AA-U1, and the lower layer AA-L2. The upper layer is a gas reservoir with initial gas in place of 1440 MMSCF, while the lower layer is an oil reservoir with initial oil in place of 6.1 MMSTB. In addition, the model design used available field data, for instance, PVT and DST, from well X. The base well completion was also used to model the completion design in software. Meanwhile, commercial software was utilized to estimate the well hydrocarbon recovery. Subsequently, several designs were tested, and the design with maximum production as well as hydrocarbon recovery was selected. The completion design selected comprises 9⅝ inch 47 ppf L-80 production casing, as well as 7⅝ inch 29.7 ppf L-80 liner, and produced commingle with oil and gas recovery of about 50.16% and 92.3%, respectively, in 5 years production

Predicting Stabilized Oil Well Inflow Performance Relationship on Unconventional Reservoir

Unconventional reservoirs are described as any reservoir that requires special recovery operations asides the conventional operating practices. However, low permeability affects the time it requires to attain stability. Presently, most of deliverability test is only carried out in a maximum 24-hour time. Limited test time makes it almost impossible to attain the reservoir stabilization time while carrying out the deliverability test. Meanwhile, to construct Inflow Performance Relationship (IPR) curve, the properties from stabilized time are required. This study aims to discuss how to predict the IPR curve by determining the stabilized flow coefficient value (C) on unconventional reservoir. Furthermore, the stabilized C was used to determine the Inflow Performance Relationship (IPR) for low porosity and permeability reservoir model, also known as Tight Oil Reservoir. The stabilized time and deliverability exponent value need to be determined before the stabilized C value. The stabilized time also know as pseudo-steady state time was evaluated from John Lee and Chaudry equation with validation from the reservoir model. The method proposed by Hashem and Kazemi, which employed the use of transient data in determining the flow coefficient value was also used. In addition, deliverability exponent (n) was determined using an equation proposed by Johnston and Lee. Furthermore, the backpressure equation from Rawlins and Schellhardt was used to construct the IPR curve.

Benefits of the Tracers Test Technique in Improving the Performance of Group Wells

This study aims to determine the benefits of the interwell tracer test technique in improving the streamline simulation on the existing array's re-look. It also analyses the best scheme for the injection spot to enhance oil recovery. This study's subject parameters are limited to the tracer's breakthrough time, produced concentration, cumulative production, and pathline movement. The results showed that previous studies distinguished the correlation between injectors and producers with the development of a new pathline that conveys a scheme of water-flood for the application. Furthermore, several developments of water-flood schemes have been executed for better oil recovery in the mature fields worldwide. The vigorous simulation model is an effort to imitate the actual field capable of enhancing the character's understanding and helping the waterflood to rinse the oil trap or the unswept pocket. Unlike a Cartesian model, the streamline conveys an enhanced portrait of the transmissibility reservoir in terms of pressure-driven. The streamline model suggests the injector's preferred position to unlock any unswept oil in the formation and minimize the water path conflict, which leads to over injection in some regions. The expected outcome is the ultimate oil increment with the original technique associated with re-patterning the wells appropriately to gain residual oil saturation in the virgin alleyway.