Maintainability of electronic instruments for meteorological applications

The concept of Maintainability (M) of electronic instruments. though of recent origin, has Important application for meteorological equipments, which have special requirements. M is defined quantitatively in terms of mean time to repair and is Influenced by the failure behaviour of an equipment. An equipment goes through teething trouble, useful and terminal phase. Much of maintainability can be incorporated during design and production phase. This reduces the effective overall cost of the equipment during its life time. Special maintenance support system is necessary for meteorological Instruments. Some recent tools for trouble shooting in digital systems have been discussed.

Borehole Seismic: Essential Contributions Over the Oilfield Lifecycle

During the evolution of the petroleum industry, surface seismic imaging has played a critical role in reservoir characterization. In the early days, borehole seismic (BHS) was developed to complement surface seismic. However, in the last few decades, a wide range of BHS surveys has been introduced to cater to new and unique objectives over the oilfield lifecycle. In the exploration phase, vertical seismic profiling (VSP) provides critical time-depth information to bridge time indexed subsurface images to log/reservoir properties in depth. This information can be obtained using several methods like conventional wireline checkshot or zero-offset vertical seismic profiling (ZVSP), seismic while drilling (SWD) or distributed acoustic sensing (DAS) techniques. SWD is a relatively new technique to record real-time data using tool deployed in the bottomhole assembly without disturbing the drilling. It helps to improve decision making for safer drilling especially in new areas in a cost-effective manner. Recently, a breakthrough technology, distributed acoustic sensing (DAS), has been introduced, where data are recorded using a fiber-optic cable with lots of saving. ZVSP also provides several parameters like, attenuation coefficient (Q), multiples prediction, impedance, reflectivity etc., which helps with characterizing the subsurface and seismic reprocessing. In the appraisal phase, BHS applications vary from velocity model update, anisotropy estimation, well- tie to imaging VSPs. The three-component VSP data is best suited for imaging and amplitude variation with offset (AVO) due to several factors like less noise interference due to quiet downhole environment, higher frequency bandwidth, proximity to the reflector, etc. Different type of VSP surveys (offset, walkaway, walkaround etc.) were designed to fulfill objectives like imaging, AVO, Q, anisotropy, and fracture mapping. In the development phase, high-resolution images (3D VSP, walkaway, or crosswell) from BHS surveys can assist with optimizing the drilling of new wells and, hence reduce costs. it can help with landing point selection, horizontal section placement, and refining interpretation for reserve calculation. BHS offers a wide range of surveys to assist the oilfield lifecycle during the production phase. Microseismic monitoring is an industry-known service to optimize hydraulic fracturing and is the only technique that captures the induced seismicity generated by hydraulic fracturing and estimate the fracture geometry (height, width, and azimuth) and in real time. During enhanced oil recovery (EOR) projects, BHS can be useful to optimize the hydrocarbon drainage strategies by mapping the fluid movement (CO2, water, steam) using time-lapse surveys like walkaway, 3D VSP and/or crosswell. DAS has brought a new dimension to provide vital information on injection or production evaluation, leak detection, flow behind tubing, crossflow diagnosis, and cement evaluation during production phase. This paper highlights the usage of BHS over the lifecycle of the oilfield.

Global warming potential of the production phase based on the example of a hotel regarding two different construction variants

The construction industry has a major influence on man-made carbon dioxide emissions. Being sustainable also means reducing or neutralizing our carbon dioxide pollution in the future. This research and the corresponding work are therefore guided by the following question: Is it possible and useful to conduct life cycle assessments and at the same time analyze the environmental impact of the construction sector? In the context of this work, a life cycle assessment of a building is performed using the example of a hotel building. All construction elements of the thermal envelope are examined from an environmental point of view by considering the global warming potential of each part of the construction. The aim of the study is to draw conclusions about the parameters that are decisive for the construction of a hotel building from an ecological standpoint in the production phase. Based on the results of the study, we want to drive the development of a “future” energy performance certificate forward that graphically illustrates the evaluation of buildings under both aspects - energy efficiency (final energy) and sustainability (GWP - global warming potential).

The body weight performance of indigenous indonesian chickens in the grower phase

Body weight is a critical parameter to monitor in chickens due to its correlation with better performance during the production phase. Hence, this study aimed to present an overview of the body weight performance of indigenous Indonesian chickens in the grower phase. The study was conducted in Gunung Kidul, Yogyakarta. Data of body weight performance data of 227 Merawang, 157 Murung Panggang, and 416 KUB chickens in the grower phase were collected. These weights were measured 4 times at 6, 8, 10, and 12 weeks while rearing the chickens in battery cages in a closed house under similar management. The result showed that the Murung Panggang chickens at each age had the highest body weight and uniformity value (P<0.05), followed by Merawang and KUB. The body growth curve of the Merawang, Murung Panggang, and KUB chickens at the 6th week showed similar weights, ranging between 400-600 g. However, at the 8th, 10th, and 12th weeks, the Merawang and Murung Panggang chickens had higher body weight performance. Therefore, this study suggested that Merawang and Murung Panggang chickens may have a greater potential to attain higher final body weights.

Avian Influenza Antibody Titer Of Laying Hens in Production Phase At District Penebel Tabanan Regency

Background: The virus of Avian Influenza (AI) H5N1 has become endemic in Indonesia since 2003. In 2012, the Avian Influenza outbreak at District Penebel caused chickens mortality in large numbers. One of the efforts to prevention the Avian Influenza outbreak is by vaccination. Therefore, supporting AI vaccination program needs diagnostic methods from post-vaccinated chickens that produce antibody titer by Hemagglutination Inhibition (HI) test. Purpose: The study aims to monitor the antibody of Avian Influenza phase I and phase II production in laying hens at District Penebel, Tabanan Regency. Method: 131 serum samples were collected from hens serums at poultry which has been sampled before. The serum sample is tested by Hemagglutination Inhibition (HI) test to calculate antibody titer. The serum is protective if the titer reacheas 24 or more, and the serum is unprotective if the titer is under 24. Data presented in 2x2 cross-sectional study contingent tabel and analyzed by Chi-Square (X2) non-parametric with the distribution. Results: Protective percentage of immunity level in production phase I in laying hens at District Penebel is 60,3%, whereas on production phase II is 43,6%. Data from the 2x2 contingent table showed an odd ratio of 1,9. The result of the Chi-Square (X2) analysis statistic represents immunity levels between production phase I and II are non-significance (p>0,05). Conclusion: Production phase I in laying hens has an immunity level 1,9x higher than production phase II. There is an association between the production phase and the protective immunity level of Avian Influenza.

Environmental Impact Assessment of Different Warm Mix Asphalts

Within the last decade, much attention has been focused on determining viable techniques for producing sustainable asphalt mixtures and minimizing fuel use and greenhouse gas emissions. Thus, warm mix asphalt (WMA) has become a topic of significant interest among road specialists as it offers a potential solution for reducing the environmental impact of the asphalt mixtures due to the decreased temperatures they require for mixing and compaction compared to hot mix asphalt (HMA). The present study is focused on the Life Cycle Assessment (LCA), according to a “Cradle-to-Gate” approach, of hot mix asphalt and warm mix asphalt prepared with locally available materials and different warm mix additives such as organic additives, chemical additive, and synthetic zeolite. For the analysis of the environmental impact of the warm mix asphalts was used a dedicated software for modeling and evaluating the LCA. The WMA prepared with chemical additive or organic additive led to a decrease of the environmental impact, in the production phase, compared to HMA. The study reveals that the raw materials extraction has the greatest impact on the environment in all studied cases, followed by the actual production phase of the asphalt mixture. For WMA produced with additives there was a decrease in the global impact on the environment compared to HMA.

Resolving Multiple Formation Damage Mechanism in Carbonate Reservoir Through Systematic Approach Using Combination of Aromatic Solvent and Less Aggressive Acid

There is no well operation that is truly non-damaging. Any invasive operation, even production phase itself, may be damaging to well productivity. An interesting case was found in L-Field which is located in South Sumatra, Indonesia. All four wells are predicted to cease to flow after five-year production and artificial lift have to be installed to prevent steep decline in oil production. Unfortunately, all of wells’ productivity index (PI) decreased post well intervention and therefore, couldn’t achieve target. The PI was continuously decreasing during production phase and aggravated the decline in oil production. Remediation action by systematic approach was applied to solve the problem. Early diagnostic revealed some potential causes through evaluation of both production and well treatment data. Laboratory test such as mineralogy analysis, crude composition and water analysis, solubility and compatibility test have been conducted and clarified the root cause that formation damage occurred in multiple mechanism related to incompatibility of the workover fluid and organic deposition. Then, possible well treatments were listed with pros and cons by considering post water production related to the carbonate reservoir properties. Subsequently, chemical matrix injection was ranked based on less possibility of water breakthrough risk. Diesel fuel and de-emulsifier injection was decided as the first treatment in order to remove formation damage caused by organic deposition. The rate was increased temporary with Water Cut (WC) remained at the same level. The subseqeuent effort was to inject low reaction chelating acid and the result showed temporary improvement and the production did achieve significant gain. Finally, the third attempt indicated promising results with the injection of aromatic solvent followed by chelating acid. The well productivity was increased to more than 20 times of the pre treatment levels. The method can be replicated to other affected wells with similar damage mechanism. High vertical permeability over horizontal permeability becomes a real threat in carbonate strong water driver reservoir in L-field. Thus, matrix acidizing treatment has to be carefully applied to prevent unwanted water production. Non-aggressive and slow reaction acid were chosen to prevent face dissolution reaction that leads to water breakthrough.

Hanging Screen Evaluation to Unlock Marginal Sandy Reservoir: Case Study of Peciko Gas Field, Indonesia

Peciko Field currently produces gas from multilayer sand-prone shallow reservoirs. Therefore, it needs sand control method to unlock these marginal reservoirs through low-cost intervention. Hanging screen has been reviewed as an alternative solution to minimize sand control cost while maintaining its robustness to maximize the recovery. This paper will present and evaluate the hanging screen installation and performance from subsurface to surface elements in Peciko field. Hanging screen implementation in Peciko will be evaluated in terms of ease of installation to its performance during production phase. Peciko wells are equipped with real-time monitoring system including Acoustic Sand Detector. Therefore, sand problems could be easily identified. Any indication of screen failure will be confirmed by checking the surface equipment like chokes and intrusive probes. Further intervention to retrieve the screen and perform visual check at surface can be executed to extend the verification. Filter size, placement method, clean-up, and sand sieve result will be gathered to identify the root cause and determine the best method to apply hanging screen as reliable sand control method. Nine installations in 2019 conclude that screen plugging, liquid loading, and combination of both are main issues in production phase. With three plugging cases from well Fx and E2x, it was found that excessive drawdown pressure triggers high gas velocity in perforation tunnel and causing excessive sand production that plugged the screen. These cases also prove that self-unloading by choke movement can lead to plugging if the drawdown pressure and gas rate are not monitored carefully. Commingle production in Ax becomes an issue in lifting performance when reservoir pressure declines and liquid was produced from several reservoirs. Limiting drawdown pressure gives smaller gas rate to lift the liquid and make the well died from liquid loading easily. Massive sand production in well E2x and E2y cause an increase in Top of Sediment (TOS) and lead to inaccessible screen even with multiple bailing attempts. A series of screen design, choke configuration, proper clean-up and continuous monitoring are critical steps to be performed prior and after screen installation to maintain production lifetime. With average stakes of 0.2 Bcf per well, hanging screen has proven to produce 67% of the well reserves in shallow reservoirs. This value creation led to the conclusion that hanging screen is an economically-feasible-sand control method to be implemented in Peciko.