CSG well testing—Santos' experience in Queensland

2013 ◽  
Vol 53 (1) ◽  
pp. 227
Author(s):  
Czek Hoong Tan ◽  
Guncel Demircan ◽  
Mathias Satyagraha

Permeability of the cleat system is a key factor controlling the productivity of CSG reservoirs and, therefore, the commerciality of development projects. Well testing is routinely used to provide representative values of coal permeability. The authors’ experience has shown pressure transient behaviour in coal reservoirs to be similar to those in primary porosity systems, with pseudo radial flow frequently observed, and the dual-porosity signature largely absent. Despite the authors’ best efforts in test design, large permeability variation and extremely high skin factors have been seen. The authors have run variations of drill stem tests (DSTs), injection tests, and wireline tests to understand the dependency of results to test methods, and the validity of results obtained. Pertinent examples of each type of test are discussed. Finally, recommendations to reconcile well test results to actual well performance are presented.

2022 ◽  
Author(s):  
Nico A. M. Vogelij

1. Abstract Various datasets are generated during hydraulic fracturing, flowback- and well-testing operations, which require consistent integration to lead to high-quality well performance interpretations. An automated digital workflow has been created to integrate and analyze the data in a consistent manner using the open-source programming language R. This paper describes the workflow, and it explains how it automatically generates well performance models and how it analyzes raw diagnostic fracture injection test (DFIT) data using numerical algorithms and Machine Learning. This workflow is successfully applied in a concession area located in the center of the Sultanate of Oman, where to date a total of 25+ tight gas wells are drilled, hydraulically fractured and well-tested. It resulted in an automated and standardized way of working, which enabled identifying trends leading to improved hydraulic fracturing and well-testing practices.


2004 ◽  
Vol 126 (3) ◽  
pp. 177-183 ◽  
Author(s):  
P. Mehdizadeh ◽  
D. T. Perry

Well testing is routinely performed to evaluate the performance of a well, which establishes the allocation factor for the lease, which in turn establishes tax and royalty basis. Most well testing is done with conventional gravity separators, which separates the produced stream into oil, water, and gas components and measures these individual components as individual streams. New multiphase measurement technology improves well test results through improved accuracy, consistency, and more frequent well testing. This paper examines the implication of these improved capabilities to recognize well problems and optimize production. A simple economic model is provided that an operator can use to assess the balance between the cost of performing periodic well tests and the benefits of more quickly discovering well problems that can result in less than expected production. The model relates the cost of decreased production, as the result of unforeseen changes in the well, to the frequency and accuracy of the well tests. The model derives an optimum test interval that minimizes the total cost of well testing and deferred production on the basis of the probability that a higher than normal decline in production rate can be detected by well testing. The model is then used in several field examples to assess the optimum period between well tests and how the optimum period can lead to reduced cost of operation and improved production.


2021 ◽  
Author(s):  
Antoine Jacques ◽  
◽  
Vincent Jaffrezic ◽  
Benoit Brouard ◽  
Shafiq Ahmed ◽  
...  

In current economic and environmental contexts, the optimization of long, horizontal well completion and the maximization of individual well performance are becoming increasingly important. The challenge is to be able to start improving the production efficiency while designing an adapted completion for each well without compromising the project economy. The cost-effective formation evaluation technique described in this paper allows rapid identification of dynamic heterogeneities along the reservoir after the drilling of a horizontal well. This key information then can be used to optimize well completion and treatment. This new approach, called WTLog, combines well testing and logging techniques and was introduced initially for the optimization of unconventional well completion (Jacques et al., 2019 and Manivannan et al. 2019). The log begins by circulating a low-viscosity liquid that can be injected in the formation through the mud cake. The brine circulation operation is run at the end of the drilling phase, after reaching TD of the drain while maintaining a constant wellhead pressure at the wellhead. The constant pressure control can be applied without a specific additional choke device when Managed Pressure Drilling (MPD) is used to drill the formation section. The inlet and outlet flowrates are measured accurately, and their difference corresponds to the apparent formation-injection rate. The depth of the interface between the two liquids inside the borehole is estimated from the flowrates and pressure measured at the wellhead. Combining these data allows derivation of the low-viscosity/liquid-injection profile along the open hole. A permeability log then can be derived by inversion. Well Test Logging has been applied successfully for the first time on two horizontal wells in a conventional carbonate reservoir. The interpretation results were benchmarked to static conventional openhole logs and validated against the data log obtained by the dynamic production log tool (PLT) performed after well start-up. This technique opens new perspectives for optimizing well completion in these carbonate-fractured formations for which porosity logs might not be a good permeability indicator and where conductive fractures seen on image logs are not always indicative of future production.


Author(s):  
P. Mehdizadeh ◽  
D. T. Perry

Well testing is routinely performed to evaluate the performance of a well, which establishes the allocation factor for the lease, which in turn establishes tax and royalty basis. Most well testing is done with conventional gravity separators, which separates the produced stream into oil, water, and gas components and measures these individual components as individual streams. New multiphase measurement technology improves well test results through improved accuracy, consistency, and more frequent well testing. This paper examines the implication of these improved capabilities to recognize well problems and optimize production. A simple economic model is provided that an operator can use to assess the balance between the cost of performing periodic well tests and the benefits of more quickly discovering well problems that can result in less than expected production. The model relates the cost of decreased production, as the result of unforeseen changes in the well, to the frequency and accuracy of the well tests. The model derives an optimum test interval that minimizes the total cost of well testing and deferred production on the basis of the probability that a higher than normal decline in production rate can be detected by well testing. The model is then used in several field examples to assess the optimum period between well tests and how the optimum period can lead to reduced cost of operation and improved production.


2019 ◽  
pp. 7-13
Author(s):  
Yury E. Katanov ◽  
Marina E. Savina ◽  
Saveliy A. Yagafarov

The article is devoted to the problem of identifying deposits in Western Siberia completely undersaturated with oil. At a primary test of such reservoirs from their roofing part joint inflows of oil with water are always received. The analysis of research results shows that the determination of the deposit area depends on a large extent on the reliability of the installed fluid contacts in the section of each well. We give examples of discrepancies between well testing interpretation and well test results. There are also examples of the groundlessness of the separation of a single geological body into several counting objects. The size of the shift of oil-water contact is determined by the action of capillary forces.


2019 ◽  
Vol 4 (2) ◽  
pp. 176-183
Author(s):  
Ponco Wali

Testing repeat electronic scales with non-automatic scales technical requirements so far is fairly long if not using a calculator or computer. The aim of this research is to compare the repeatability testing method of electronic scales using methods according to the technical requirements of non-automatic scales and the Australian NMI method, both of which refer to OIML R76 in determining the validity or cancellation of electronic scales repeatability testing. This research method is done through repeat testing on 3 samples of electronic scales, then on each electronic scale 2 test methods are performed. The conclusion is that the electronic scales repeatability testing uses the non-automatic scales technical requirements method and the Australian NMI method has some differences although both refer to OIML R76. These differences include several points, namely the charge used, the method of adding additions, the formula for determining electronic scales, and different test results. The Australian NMI method is deemed to make it easier and more time efficient compared to the non-automatic weighing technical requirements method.


Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 670
Author(s):  
Preeda Chaturabong

Chip seal bleeding is influenced by many factors, including design inputs, material properties, and project-specific conditions. It reduces the surface texture of the pavement and thus compromises the safety of the traveling public. Even though factors that bring about premature bleeding are known, currently, no laboratory test methods for evaluating bleeding in chip seals have been specified. The objective of this paper is to present the results of an investigation of the influence factors of asphalt emulsion residue properties measured by the ASTM D7405 multiple stress creep and recovery (MSCR) test, as well as other factors related to chip seal bleeding resistance as measured by the modified loaded wheel test (MLWT). In this study, the MSCR test was used as a tool for evaluating the performance of asphalt emulsions because it has been identified as a potential test related to bleeding in the field. In addition, MLWT was selected as a tool for evaluating chip seal bleeding performance in the laboratory. The results of the MLWT showed that the emulsion application rate (EAR), aggregate gradation, and emulsion properties were significant factors affecting bleeding. The MSCR test was found to be a promising tool for the performance evaluation of asphalt emulsion residue, as the test was able to differentiate between emulsion chemistries and modifications in terms of sensitivity to both temperature and stress. In relation to chip seal bleeding resistance, only the creep compliance (Jnr) obtained from the MSCR test results was identified as a significant property affecting potential for bleeding.


2013 ◽  
Vol 345 ◽  
pp. 64-67
Author(s):  
Jian Hua Zhao ◽  
Rui Bo Zhang ◽  
De Bin Zhu ◽  
Hong Bin Gao

Shock test of marine diesel engine is the important content for ship anti-shock research. Plentiful shock tests of equipments have been carried out abroad, but there is no detailed test methods of diesel engine. According to simulation results, 8-channel acceleration test points are determined. Because diesel engine is working, the measured shock acceleration is interfered by vibration signal. Orthogonal wavelet decomposition and wavelet noise reduction methods are used to separate shock component from test results. The seperated shock component consists of two parts. One is the low-frequency part caused by the shock from diesel foundation and then attenuation through the isolator, the other is the high-frequency part caused by the secondary shock of the retainer.


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