Hosatte, Pierre (Shell Global Solutions International B.V.) | Anderson, Ryan N. (Shell International EP) | Venugopal, Shangkar (Halliburton Energy Services) | Marimuthu, Suresh (Halliburton Energy Services) | Bidi, Firdaus (Halliburton Energy Services) | McBain, Ben (Halliburton Energy Services) | Royce, Peter (Halliburton Energy Services)
This paper reviews an offshore Malaysia deepwater appraisal well drilled and tested Q1 2016 and presents innovative drillstem testing (DST) solutions specifically engineered and developed to enable efficient deployment, safe production, and successful collection of representative downhole hydrocarbon samples from a challenging carbonate gas reservoir.
The following DST solutions and methodologies are presented: An Open-Hole DST design to address downhole fractured conditions with multiple zones prone to total losses and deployed using pressurized mud cap drilling (PMCD) mode, providing high operational efficiency with no requirements for tubing conveyed perforating (TCP). A subsea safety test tree (SSTT) system operating philosophy and fit-for-purpose subsea well controls contingency procedures to ensure safe emergency shutdown (ESD) and emergency quick disconnect (EQD) from a dynamic positioning (DP) rig. A carefully designed wireless acoustic telemetry system to enable real-time collection of multiple downhole samples of reservoir fluids and real-time bottomhole data transmission for critical decision making. A production shutdown (PSD) system using a state-of-the-art programmable logic controller (PLC) for effective ESD in high-H2S environments.
An Open-Hole DST design to address downhole fractured conditions with multiple zones prone to total losses and deployed using pressurized mud cap drilling (PMCD) mode, providing high operational efficiency with no requirements for tubing conveyed perforating (TCP).
A subsea safety test tree (SSTT) system operating philosophy and fit-for-purpose subsea well controls contingency procedures to ensure safe emergency shutdown (ESD) and emergency quick disconnect (EQD) from a dynamic positioning (DP) rig.
A carefully designed wireless acoustic telemetry system to enable real-time collection of multiple downhole samples of reservoir fluids and real-time bottomhole data transmission for critical decision making.
A production shutdown (PSD) system using a state-of-the-art programmable logic controller (PLC) for effective ESD in high-H2S environments.
The DST solutions developed enabled appropriate management of the operational risks identified and provided increased levels of contingencies to guarantee successful and efficient delivery of the well objectives. High-quality downhole samples of reservoir fluids were collected, and the overall key objectives of the well test in terms of reservoir characterization were successfully achieved in a cost effective manner with reduced personnel, health, safety, security, environment (HSSE) and process safety (PS) exposure. This paper showcases how innovative DST solutions, engineered to suit well conditions and combined with fit-for-purpose operational procedures, enabled the safe, efficient, and successful delivery of critical well objectives in a challenging and hostile deepwater environment.
In this paper, sand screen integrity in two depleting reservoirs is evaluated using fluid-mechanical coupling analysis. Both analyses use a numerical model for rock-structure interaction. In the first, a horizontal completion in a soft sandstone reservoir is evaluated. This analysis used laboratory tests to measure the properties of ceramic proppant, the formation sandstone and sand screen. The numerical model included friction hardening and volumetric hardening of the formation, friction hardening of the gravel pack, and the crushing strength of the screen base pipe which were all measured in the laboratory. In the second, a vertical gravel pack in a stiff strong formation was analyzed to evaluate gravel screen contact loads under very high levels of depletion and drawdown. While this analysis did not include a laboratory program, using instead existing core data, it did model the effect of near wellbore damage on the contact load. The results show that loads on sand control completions can be estimated and the workflow demonstrated here is a way to select durable sand control completions.
Jin, Long (Shell) | Gao, Guohua (Shell) | Vink, Jeroen C. (Shell Intl. E&P Co.) | Chen, Chaohui (Shell International EP) | Weber, Daniel (Shell Intl. E&P Co.) | Alpak, Faruk Omer (Shell Intl. E&P Co.) | van den Hoek, Paul (Shell) | Pirmez, Carlos (Shell Intl. E&P Co.)
Quantitative integration of 4D seismic data with production data into reservoir models is a challenging task. One important issue is how to properly quantify the uncertainty, or the posterior probability distribution (PPD). The Very Fast Simulated Annealing (VFSA) is a stochastic searching method, whereas the Simultaneous Perturbation and Multivariate Interpolation (SPMI) is a model-based local searching method. The stochastic features of the VFSA provide the feasibility of identifying possible multiple peaks of a PPD, but it converges very slowly. On the other hand, the model-based SPMI method has the advantages of effectively utilizing the smooth features of an objective function, and thus can converge to local optimum very quickly. More importantly, the Hessian of the objective function, or the covariance matrix of the PPD, can be estimated by the SPMI method with satisfactory accuracy. However, it is very difficult to identify multiple optima by applying the SPMI method alone. In this paper, we propose an efficient joint inversion workflow by appropriately integrating the two derivative
free optimization (DFO) methods. The complementary features of the two methods can further improve both applicability and efficiency of this joint inversion workflow. We tested the workflow with a 3D synthetic model and a real field case. Our results show that the integrated method is efficient and can deliver good results for jointly assimilating 4D seismic and production data.
Chen, Chaohui (Shell International EP) | Jin, Long (Shell) | Gao, Guohua (Shell) | Weber, Daniel (Shell Intl. E&P Co.) | Vink, Jeroen C. (Shell Intl. E&P Co.) | Hohl, Detlef (Shell Intl. E&P BV) | Alpak, Faruk Omer (Shell Intl. E&P Co.) | Pirmez, Carlos (Shell Exploration and Production Company)
Gradient-based optimization algorithms can be very efficient in history matching problems. Since many commercial reservoir simulators do not have an adjoint formulation built in, exploring capability and applicability of derivative-free optimization (DFO) algorithms is crucial. DFO algorithms treat the simulator as a black box and generate new searching points using objective function values only. DFO algorithms usually require more function evaluations, but this obstacle can be overcome by exploiting parallel computing.
This paper tests three DFO algorithms, Very Fast Simulated Annealing (VFSA), Simultaneous Perturbation and Multivariate Interpolation (SPMI) and Quadratic Interpolation Model-based (QIM) algorithm. Both SPMI and QIM are model-based methods. The objective function is approximated by a quadratic model interpolating points evaluated in previous iterations, and new search points are obtained by minimizing the quadratic model within a trust region. VFSA is a stochastic search method. These algorithms were tested with two synthetic cases (IC fault model and Brugge model) and one deepwater field case. Principal Component Analysis is applied to the Brugge case to parameterize the reservoir model vector to less than 40 parameters.
We obtained good matches with all three derivative-free methods. In terms of number of iterations used for converging and the final converged value of the objective function, SPMI outperforms the others. Since SPMI generates a large number of perturbation and search points simultaneously in one iteration, it requires more computer resources. QIM does not generate as many interpolation points as SPMI, and it converges more slowly in terms of time. VFSA is a sequential method and usually requires hundreds of iterations to converge.
Copyright 2012, Society of Petroleum Engineers This paper was prepared for presentation at the SPE International Conference and Exhibition on Oilfield Corrosion held in Aberdeen, UK, 28-29 May 2012. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright. Typically used standard methods for microbial identification (i.e. MPN) have limited success at identifying problematic organisms and providing timely feedback. A three-part approach was developed and implemented at Shell‟s Ursa platform to understand whether recent failures on the production system were the result of MIC and the efficiency of the biocontrol strategy on the recently installed waterflood to prevent system failure and reservoir souring. The approach involved 2nd generation ATP quantification for rapid enumeration of actively-growing microorganisms, as well as microbial enumeration and speciation using molecular methods. Recent failures on the production system were believed to be the result of under-deposit corrosion and microbial attack.
Brooks, David (Shell Intl. E&P Co.) | De Zwart, Albert Hendrik (Shell Intl. E&P Co.) | Bychkov, Andrey (Shell) | Azri, Nasser (Shell International EP) | Hern, Carolinne (Shell) | Al Ajmi, Widad (Petroleum Development Oman) | Mukmin, Mukmin (Petroleum Development Oman)
Power, Michael Roderic (Shell International EP)
Liedtke, E.A. (BP America Inc) | Clukey, E.C. (BP America Inc) | Horkowtz, K.O. (BP America Inc) | Hill, A.W. (BP America Inc) | Humphrey, G.D. (Fugro-McClelland Marine Geosciences, Inc) | Dean, J.R. (Shell International EP)