Hollow Glass Spheres HGS in Drilling Fluid: Case Study of Preventing and Mitigating Total Losses

2021 ◽  
Author(s):  
Vitaly Sherishorin ◽  
Martin Rylance ◽  
Yevgeniy Tuzov ◽  
Olga Krokhaleva ◽  
Evgeny Tikhonov ◽  
...  

Abstract The paper describes the first deployment of HGS in Eastern Siberia as a mud additive. The technology was utilized for reducing drilling fluid density for prevention and mitigation of losses; while drilling through a producing reservoir section with low pore pressure, unconsolidated and fractured sands. The engineering considerations, fundamentals of the approach and major risks involved were reviewed with application to the Sredneboutobinskoye Oilfield as a pilot field application for broader future plans. Key planning, delivery and execution principles of the initial application will be reported in the paper. Initially deployed on three wells, including multi-laterals (Rylance et al., 2021), the paper will walk through the engineering considerations during the planning and execution phases. Key sections include the data gathered and the many lessons learned during the incremental and stepwise deployment. The paper will also report on post drilling productivity and comparisons with the offset wells drilled with conventional mud systems, which suffered severe losses. The results of this pilot have exceeded expectations. There have been many insights and the Team are now looking to set a timetable to scale-up across the Taas-Yuryakh Neftegazodobycha (TYNGD). After many hours of laboratories study and preparation works, the general plan was to reduce the static density and ECD to mitigate fluid losses. However, the applied results showed additional effects from HGS. Data will be provided that demonstrated loss-free drilling was achieved where this had not been the case before, with a material reduction in NPT, lost circulation material (LCM) needs and costs. Much has been learned, recovered HGS material has been demonstrated to be an effective LCM pill and centralization of mud processing may offer additional cost savings and improvements. Further efficiencies are also expected to be achieved and future potential is considerable. HGS for cementing is well documented, yet application for drilling fluids has been less well reported and almost exclusively related to single wells. The TYNGD application is innovative as this is a major development with 10 active drilling rigs. The application is on multi-laterals and offset wells are available for direct comparison. The results of the approach demonstrate a new way of performing well construction in an effective manner for major field developments where losses are prevalent.

2021 ◽  
Author(s):  
M.. Rylance ◽  
Y.. Tuzov ◽  
V.. Sherishorin

Abstract A major development with multiple rigs delivering extensive multi-laterals encountered a pervasive mud-window issue within the reservoir. The resulting severe mud losses, extensive NPT and formation-damage was also deteriorating with time due to depletion. Conventional approaches to stem losses had failed and adoption of an energized mud-system with acceptable Effective Circulating Density (ECD) was not considered cost effective, pragmatic nor safe. Instead a novel application using Hollow-Glass-Spheres (HGS) was trialled, that demonstrated an effective and highly successful outcome. With 10 rigs drilling 60-70 wells per-year, each with 5,500 to 6,750m in the reservoir, quick resolution of the issue was required. For these reasons the Team at bp Russia looked carefully at alternatives that might fit the mud-window, but that offered a realistic approach for the environment and conditions in Eastern Siberia. The Team identified HGS as an approach to lighten the mud, often used for cementing ECD, application for drilling has been limited. For this approach we required an option with broad capabilities that could be scaled-up and exported to other development areas where such issues existed. This paper will report on the planning, delivery, and execution of a pilot on the Sb. field at TYNGD, in Eastern Siberia. Initially deployed on three wells, including multi-laterals, the paper will walk through the engineering considerations, during the planning and execution phases. Reporting comprehensively on the data gathered and the many lessons learned during the incremental and stepwise deployment. Data will be provided that demonstrated loss-free drilling was achieved where this had not occurred before, with a dramatic reduction in NPT, FLA needs and costs. The paper will also report on the post drilling productivity and comparison with offset wells drilled with conventional mud systems and suffering severe losses. The results of this pilot have beaten all expectations, there have been many insights and the Team are now looking to set a timetable to scale-up across the NOJV. Much has been learned, waste HGS material has been demonstrated to be an effective FLA pill in other sections of the well and centralisation of mud process may offer additional cost savings and improvements. Further efficiencies are expected to be achieved and potential across the Company portfolio could be a major game changer. HGS for cementing is well documented, application for drilling fluids has been less reported and almost exclusively applied to one-off sections/wells. The TYNGD application is novel as this is a major new development with 10 drilling rigs. Application is on multi-laterals and prior offset wells are available for direct comparison. The results of the approach demonstrate a new way of performing well construction in an effective manner for major Field Developments where losses are prevalent.


2021 ◽  
Author(s):  
Chen Hongbo ◽  
Okesanya Temi ◽  
Kuru Ergun ◽  
Heath Garett ◽  
Hadley Dylan

Abstract Recent studies highlight the significant role of drilling fluid elasticity in particle suspension and hole cleaning during drilling operations. Traditional methods to quantify fluid elasticity require the use of advanced rheometers not suitable for field application. The main objectives of the study were to develop a generalized model for determining viscoelasticity of a drilling fluid using standard field-testing equipment, investigate the factors influencing drilling fluid viscoelasticity in the field, and provide an understanding of the viscoelasticity concept. Over 80 fluid formulations used in this study included field samples of oil-based drilling fluids as well as laboratory samples formulated with bentonite and other polymers such as partially-hydrolyzed polyacrylamide, synthesized xanthan gum, and polyacrylic acid. Detailed rheological characterizations of these fluids used a funnel viscometer and a rotational viscometer. Elastic properties of the drilling fluids (quantified in terms of the energy required to cause an irreversible deformation in the fluid's structure) were obtained from oscillatory tests conducted using a cone-and-plate type rheometer. Using an empirical approach, a non-iterative model for quantifying elasticity correlated test results from a funnel viscometer and a rotational viscometer. The generalized model was able to predict the elasticity of drilling fluids with a mean absolute error of 5.75%. In addition, the model offers practical versatility by requiring only standard drilling fluid testing equipment to predict viscoelasticity. Experimental results showed that non-aqueous fluid (NAF) viscoelasticity is inversely proportional to the oil-water ratio and the presence of clay greatly debilitates the elasticity of the samples while enhancing their viscosity. The work efforts present a model for estimating drilling fluid elasticity using standard drilling fluid field-testing equipment. Furthermore, a revised approach helps to describe the viscoelastic property of a fluid that involves quantifying the amount of energy required to irreversibly deform a unit volume of viscoelastic fluid. The methodology, combined with the explanation of the viscoelasticity concept, provides a practical tool for optimizing drilling operations based on the viscoelasticity of drilling fluids.


Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-18 ◽  
Author(s):  
Biao Ma ◽  
Xiaolin Pu ◽  
Zhengguo Zhao ◽  
Hao Wang ◽  
Wenxin Dong

The lost circulation in a formation is one of the most complicated problems that have existed in drilling engineering for a long time. The key to solving the loss of drilling fluid circulation is to improve the pressure-bearing capacity of the formation. The tendency is to improve the formation pressure-bearing capacity with drilling fluid technology for strengthening the wellbore, either to the low fracture pressure of the formation or to that of the naturally fractured formation. Therefore, a laboratory study focused on core fracturing simulations for the strengthening of wellbores was conducted with self-developed fracture experiment equipment. Experiments were performed to determine the effect of the gradation of plugging materials, kinds of plugging materials, and drilling fluid systems. The results showed that fracture pressure in the presence of drilling fluid was significantly higher than that in the presence of water. The kinds and gradation of drilling fluids had obvious effects on the core fracturing process. In addition, different drilling fluid systems had different effects on the core fracture process. In the same case, the core fracture pressure in the presence of oil-based drilling fluid was less than that in the presence of water-based drilling fluid.


2007 ◽  
Vol 4 (1) ◽  
pp. 103 ◽  
Author(s):  
Ozcan Baris ◽  
Luis Ayala ◽  
W. Watson Robert

The use of foam as a drilling fluid was developed to meet a special set of conditions under which other common drilling fluids had failed. Foam drilling is defined as the process of making boreholes by utilizing foam as the circulating fluid. When compared with conventional drilling, underbalanced or foam drilling has several advantages. These advantages include: avoidance of lost circulation problems, minimizing damage to pay zones, higher penetration rates and bit life. Foams are usually characterized by the quality, the ratio of the volume of gas, and the total foam volume. Obtaining dependable pressure profiles for aerated (gasified) fluids and foam is more difficult than for single phase fluids, since in the former ones the drilling mud contains a gas phase that is entrained within the fluid system. The primary goal of this study is to expand the knowledge-base of the hydrodynamic phenomena that occur in a foam drilling operation. In order to gain a better understanding of foam drilling operations, a hydrodynamic model is developed and run at different operating conditions. For this purpose, the flow of foam through the drilling system is modeled by invoking the basic principles of continuum mechanics and thermodynamics. The model was designed to allow gas and liquid flow at desired volumetric flow rates through the drillstring and annulus. Parametric studies are conducted in order to identify the most influential variables in the hydrodynamic modeling of foam flow. 


2011 ◽  
Vol 134 (1) ◽  
Author(s):  
J. Abdo ◽  
M. Danish Haneef

The idea of pushing the limits of drilling oil and gas wells by improving drilling fluids for undemanding and cost efficient drilling operations by extracting advantage from the wonders of nanotechnology forms the basis of the work presented here. Foremost, in order to highlight the significance of reducing the size distribution of particles, new clay ATR which has a chain like structure and offers enormous surface area and increased reactivity was tested in different sizes that were chemically and mechanically milled. Bentonite which is a commonly used drilling fluid additive was also tested in different particle size distribution (PSD) and rheological properties were tested. Significant reduction in viscosity with small sized particles was recorded. The tested material called ATR throughout this paper is shown to offer better functionality than bentonite without the requirement of other expensive additives. Experiments were performed with different size distributions and compositions and drastic changes in rheological properties are observed. A detailed investigation of the shear thinning behavior was also carried out with ATR samples in order to confirm its functionality for eliminating the problem of mechanical and differential pipe sticking, while retaining suitable viscosity and density for avoidance of problems like lost circulation, poor hole cleaning and inappropriate operating hydrostatic pressures.


Author(s):  
Anne Schulz ◽  
Heike Strauß ◽  
Matthias Reich

Rheological analysis provides a good comprehension of the deformation and flow of substances under different stress conditions. The complex composition of the drilling fluid and the versatile functions makes rheological studies here indispensable as well as in other scientific fields like the food industry and material science. In spite of adding many high-quality additives to the drilling fluids, problems still occur, such as barite-sag, lost circulation, change of mud properties (particularly at high and very low temperature), solids transport. Others are often mentioned as reasons for increasing the cost of wells. The areas in which rheology plays an important role in drilling technology will be highlighted in this article. The reason, why the characterization with the Fann-viscometer alone is not enough for a detailed view on rheology will be focused on. In addition, measuring methods which are able to provide detailed information about gel strength, consistency, gel destruction, gel build up process and yield point have been investigated. A short overview of the basics of rheology is given. In this article, novel procedures will be shown on the basis of flow curve, hysteresis loops, amplitude sweep and 3-interval-thixotropy-test (3ITT). With these procedures, deeper knowledge about the drilling fluid system can be obtained. Implementing these procedures and considering their results in hydraulic calculation programs or taking them into account by the design of drilling fluids, can reduce costs and lead to safer drilling process in general.


2021 ◽  
Author(s):  
Gaston Lopez ◽  
Gonzalo Vidal ◽  
Claus Hedegaard ◽  
Reinaldo Maldonado

Abstract Losses, wellbore instability, and influxes during drillings operations in unconventional fields result from continuous reactivity to the drilling fluid causing instability in the microfractured limestone of the Quintuco Formation in Argentina. This volatile situation becomes more critical when drilling operations are navigating horizontally through the Vaca Muerta Formation, a bituminous marlstone with a higher density than the Quintuco Formation. Controlling drilling fluids invasion between the communicating microfractures and connecting pores helps to minimize seepage losses, total losses, wellbore fluid influxes, and instabilities, reducing the non-productive time (NPT) caused by these problems during drilling operations. The use of conventional sealants – like calcium carbonate, graphite, asphalt, and other bridging materials – does not guarantee problem-free drilling operations. Also, lost circulation material (LCM) is restricted because the MWD-LWD tools clearances are very narrow in these slim holes. The challenge is to generate a strong and resistant seal separating the drilling fluid and the formation. Using an ultra-low-invasion technology will increase the operative fracture gradient window, avoid fluid invasion to the formation, minimize losses, and stop the cycle of fluid invasion and instability, allowing operations to maintain the designed drilling parameters and objectives safely. The ultra-low-invasion wellbore shielding technology has been applied in various fields, resulting in significantly improved drilling efficiencies compared to offset wells. The operator has benefited from the minimization of drilling fluids costs and optimization in drilling operations, including reducing the volume of oil-based drilling fluids used per well, fewer casing sections, and fewer requirements for cementing intervals to solve lost circulation problems. This paper will discuss the design of the ultra-low-invasion technology in an oil-based drilling fluid, the strategy for determining the technical limits for application, the evaluation of the operative window with an increase in the fracture gradient, the optimized drilling performance, and reduction in costs, including the elimination of NPT caused by wellbore instability.


2021 ◽  
Author(s):  
Mohammed Alkhalifah ◽  
Rabih Younes

Abstract In an oil field, openhole multilateral maximum reservoir contact (MRC) wells are drilled. These wells are typically equipped with smart well completion technologies consisting of inflow control valves and permanent downhole monitoring systems. Conventional flowback techniques consisted of flowing back the well to atmosphere while burning the hydrocarbon and drilling fluids brought to surface. In an age of economic, environmental and safety consciousness, all practices in the petroleum industry are being examined closely. As such, the conventional method of flowing back wells is frowned upon from all aspects. This gives rise to the challenge of flowing back wells in an economic manner without compromising safety and the environment; all the while ensuring excellent well deliverability. By utilizing subsurface smart well completion inflow control valves, individual laterals are flowed to a separator system whereby solid drill cuttings are captured and discharged using a solids management system. Hydrocarbons are separated using a separation vessel and measured before being sent to the production line toward the field separation facility. Permanent downhole monitoring systems are used to monitor pressure drawdown and subsequently control the rate of flow to surface to ensure reservoir integrity. Following the completion of the solids and drilling fluid flowback from the wellbore, comprehensive multi-rate measurements at different choke settings are obtained to quantify the well performance. This paper looks at the economic and environmental improvements of the adopted zero flaring cleanup technology and smart well completions flowback techniques in comparison to conventional flowback methods. This ensures that oil is being recovered during well flowback and lateral contribution to overall flow in multilateral wells. In addition, it highlights the lessons learned and key best practices implemented during the cleanup operation to complete the job in a safe and efficient manner. This technique tends to set a roadmap for a better well flowback that fulfills economic constrains and protects the environment.


2013 ◽  
Vol 651 ◽  
pp. 717-721 ◽  
Author(s):  
Jin Feng Wang ◽  
Jin Gen Deng

Fuzzy ball drilling fluids have been developed in order to effectively control lost circulation during CBM drilling. Depending upon fuzzy balls and colloids in fuzzy balls, the fuzzy ball drilling fluids changed their shapes and properties to completely plug underground heterogeneous seepage channels so as to strengthen the pressure bearing capacity of formations. This paper describes the available features of the fuzzy ball drilling fluid including efficient plugging, good carrying and suspension, formation damage control, compatible weighted by any weighted materials without auxiliary equipment. The fuzzy ball drilling fluids can finish drilling in low pressure natural gas zone, control CBM leakage; control the natural fractures, drilling in different pressures in the same open hole, combination with the air drilling mode, etc. during Ordos CBM drilling. The fuzzy ball drilling fluid will not affect down-hole motors and MWD. The fuzzy ball drilling fluid will be blend simply as conventional water based drilling fluids. The existing CBM drilling equipment can completely meet the fuzzy ball drilling mixing and it is maintained conveniently. The fuzzy ball drilling fluid is the efficient drilling fluid.


Author(s):  
Winarto S. ◽  
Sugiatmo Kasmungin

<em>In the process of drilling for oil and gas wells the use of appropriate drilling mud can reduce the negative impacts during ongoing drilling and post-drilling operations (production). In general, one of the drilling muds that are often used is conventional mud type with weighting agent barite, but the use of this type of mud often results in skin that is difficult to clean. Therefore in this laboratory research an experiment was carried out using a CaCO3 weigting agent called Mud DS-01. CaCO3 is widely used as a material for Lost Circulation Material so that it is expected that using CaCO3 mud will have little effect on formation damage or at least easily cleaned by acidizing. The aim of this research is to obtain a formula of mud with CaCO3 which at least gives formation damage. Laboratory experiments on this drilling mud using several mud samples adjusted to the property specifications of the mud program. Mud sample consists of 4, namely using super fine, fine, medium, and conventional CaCO3. First measuring mud properties in each sample then testing the filter cake breaker, testing the initial flow rate using 200 ml of distilled water and a 20 micron filter disk inserted in a 500 ml HPHT cell then assembled in a PPA jacket and injecting a pressure of 100 psi. The acidification test was then performed using 15% HCL and then pressured 100 psi for 3 hours to let the acid work to remove the cake attached to the filter disk (acidizing). Laboratory studies are expected which of these samples will minimize the formation damage caused by drilling fluids.</em>


Sign in / Sign up

Export Citation Format

Share Document