Low ECD High Performance Invert Emulsion Drilling Fluids: Lab Development and Field Deployment

2021 ◽  
Author(s):  
Vikrant Wagle ◽  
Abdullah Yami ◽  
Michael Onoriode ◽  
Jacques Butcher ◽  
Nivika Gupta
Keyword(s):  
High Performance ◽  
Filter Cake ◽  
Drilling Fluid ◽  
Field Performance ◽  
Superior Performance ◽  
Core Material ◽  
Drilling Fluids ◽  
Invert Emulsion ◽  
Field Deployment ◽  
Permeability Studies

Abstract The present paper describes the results of the formulation of an acid-soluble low ECD organoclay-free invert emulsion drilling fluid formulated with acid soluble manganese tetroxide and a specially designed bridging package. The paper also presents a short summary of field applications to date. The novel, non-damaging fluid has superior rheology resulting in lower ECD, excellent suspension properties for effective hole cleaning and barite-sag resistance while also reducing the risk of stuck pipe in high over balance applications. 95pcf high performance invert emulsion fluid (HPIEF) was formulated using an engineered bridging package comprising of acid-soluble bridging agents and an acid-soluble weighting agent viz. manganese tetroxide. The paper describes the filtration and rheological properties of the HPIEF after hot rolling at 300oF. Different tests such as contamination testing, sag-factor analysis, high temperature-high pressure rheology measurements and filter-cake breaking studies at 300oF were performed on the HPIEF. The 95pcf fluid was also subjected to particle plugging experiments to determine the invasion characteristics and the non-damaging nature of the fluids. The 95pcf HPIEF exhibited optimal filtration properties at high overbalance conditions. The low PV values and rheological profile support low ECDs while drilling. The static aging tests performed on the 95pcf HPIEF resulted in a sag factor of less than 0.53, qualifying the inherent stability for expected downhole conditions. The HPIEF demonstrated resilience to contamination testing with negligible change in properties. Filter-cake breaking experiments performed using a specially designed breaker fluid system gave high filter-cake breaking efficiency. Return permeability studies were performed with the HPIEF against synthetic core material, results of which confirmed the non-damaging design of the fluid. The paper thus demonstrates the superior performance of the HPIEF in achieving the desired lab and field performance.

Fate of Emulsifier in Invert Emulsion Drilling Fluids: Hydrolysis and Adsorption on Solids

2021 ◽  
Author(s):  
Dimitri Khramov ◽  
Evgeny Barmatov
Keyword(s):  
High Performance ◽  
Drilling Fluid ◽  
Freundlich Isotherm ◽  
Model Systems ◽  
Chemical Degradation ◽  
Fluid Loss ◽  
Resonance Spectroscopy ◽  
Drilling Fluids ◽  
Invert Emulsion ◽  
Emulsifier Concentration

Abstract Emulsifier concentration in SBM is an important factor of drilling fluid stability. Proper concentration of amidoamine emulsifier is imperative for controlling low fluid loss and maintaining emulsion stability. This study investigates the physical and chemical interactions between emulsifier and other additives and describes the processes by which emulsifier is depleted from the drilling fluid. Three main pathways of emulsifier consumption are identified: emulsifier adsorption on solids found in drilling fluids and low gravity solids (LGS), chemical degradation, and to stabilize the invert emulsion. Design of experiments model and analytical procedure based on 1H NMR (nuclear magnetic resonance) spectroscopy was used to quantify the required emulsifier concentration in Non-Aqueous Fluid system (NAF). Additionally, model systems were used to estimate the excess of emulsifier, evaluate the emulsifier losses due to alkaline hydrolysis at elevated temperature, and measure adsorption of emulsifier on barite and various LGS types. Calculations for emulsifier depletion based on model systems were correlated to performance of formulated drilling fluids for verification. Typical emulsifier requirement in high performance NAF is 8-12 pounds per barrel (ppb). Majority of the emulsifier is adsorbed on weighting agents (barite) and rheology modifiers (clays), which are used to formulate NAF, that contribute to their effective dispersion in the solution and control fluid rheology. The adsorption process is found to be sensitive to the emulsifier concentration, solids mineralogy, wetting agent and temperature. Analytical Langmuir-Freundlich isotherm was used to describe adsorption data and estimate the adsorption capacity of the system. The emulsifier degradation pathway is another important factor of emulsifier consumption; however, emulsifier degradation at 250°F is not significant. While NAF are generally run ‘rich’ to mitigate depletion and maintain fluid stability, adsorption onto minerals will become an issue especially at high LGS concentration. These results will be greatly beneficial in the further development of NAF drilling fluid formulations and will assist field engineers in understanding the effect excess emulsifier will have on the drilling fluid and enable them to more effectively control the fluid properties under variations in emulsifier and LGS concentration during drilling.

Investigation of Biodiesel-Based Drilling Fluid, Part 1: Biodiesel Evaluation, Invert-Emulsion Properties, and Development of a Novel Emulsifier Package

SPE Journal ◽  
2016 ◽  
Vol 21 (05) ◽  
pp. 1755-1766 ◽  
Author(s):  
Wai Li ◽  
Xionghu Zhao ◽  
Yihui Ji ◽  
Hui Peng ◽  
Bin Chen ◽  
...  
Keyword(s):  
High Performance ◽  
Drilling Fluid ◽  
Low Cost ◽  
Hydrolytic Stability ◽  
Waste Cooking Oil ◽  
Drilling Fluids ◽  
Base Oil ◽  
Cooking Oil ◽  
Invert Emulsion ◽  
Organophilic Clay

Summary As a type of mono-alkyl ester, biodiesel exhibits great potential to serve as the base oil of drilling fluids substituting for conventional oil-based drilling fluids (OBDFs). This paper presents a series of laboratory investigations of water-in-biodiesel (invert) emulsion as the basis of a high-performance, environmentally friendly, and low-cost biodiesel-based drilling fluid (BBDF). Biodiesel produced from waste cooking oil was used to formulate a BBDF because of its high flashpoint, reliable storage stability, acceptable elastomeric material compatibility, nontoxicity, and excellent biodegradability. In light of the results of tests used to measure various properties, the biodiesel invert-emulsion chemistry, including the required hydrophile/lipophile balance (HLB), optimal emulsifier, effects of different additives (organophilic clay, calcium chloride, and lime), as well as hydrolytic stability, was studied. A biodiesel invert emulsion that remains stable after hot rolling at 120°C for 16 hours can be prepared with correct combinations of additives, thereby offering a firm foundation for designing BBDFs. The novel emulsifier package developed in this work is introduced as an achievement in the comprehensive usage of waste cooking oil because its feedstock is identical to that of biodiesel. An initial economic analysis of the use of biodiesel for drilling is also presented. Details of the formulations and properties of BBDFs derived from this fundamental research are discussed in another paper (Part 2).

Sagging Prevention for Hematite-Based Invert Emulsion Mud

2021 ◽  
pp. 1-19
Author(s):  
Ashraf Ahmed ◽  
Salem Basfer ◽  
Salaheldin Elkatatny
Keyword(s):  
Laboratory Experiments ◽  
Filter Cake ◽  
Emulsion Stability ◽  
Gel Strength ◽  
Drilling Fluids ◽  
Drilling Mud ◽  
High Pressure High Temperature ◽  
Solids Suspension ◽  
Invert Emulsion ◽  
Drilling Cost

Abstract The solids sagging in high-pressure high-temperature (HP/HT) reservoirs is a common challenge associated with hematite drilling fluids. This study provides a solution to hematite sagging in invert emulsion mud for HP/HT wells which involves the combination of Micromax (Mn3O4) with hematite. The particles of both weighting agents were characterized to address their mineralogical features. A Field formulation of the mud was used over a range of Micromax/hematite ratios (0/100, 20/80, and 30/70%) in laboratory experiments to address the sag performance and determine the optimal combination ratio. Then, density, emulsion stability, rheology, viscoelasticity, and filtration performance for the formulated mud were addressed. The tests were conditioned to 500 psi and 350 °F. The acquired results of sag tests indicated that incorporation of 30% Micromax solved the hematite sagging issue and brought the sag tendency within the recommended safe range. An insignificant reduction in mud density was observed upon the inclusion of Micromax, while the emulsion stability was obviously improved from 551 to 614 volts with the 30% Micromax mixture. The recommended 30/70% combination had almost no effect on plastic viscosity and yield point since they were increased by one unit, but the gel strength was improved resulting in flat rheology and better solids suspension capacity. The filtration behavior of the formulation with 30% Micromax was enhanced compared to pure hematite as it resulted in 10 and 14% reduction of the filtrate volume and filter-cake thickness, respectively. This study contributes to improve and economize the drilling cost and time by formulating a stabilized and distinguished-performance drilling mud using combined weighting agents at HP/HT.

Well Clean-Up Using a Combined Thermochemical/Chelating Agent Fluids

2019 ◽  
Vol 141 (10) ◽  
Author(s):  
Mohamed Mahmoud
Keyword(s):  
High Temperature ◽  
Filter Cake ◽  
Oil And Gas ◽  
Drilling Fluid ◽  
Chelating Agent ◽  
Drilling Fluids ◽  
Gas Wells ◽  
Oil And Gas Wells ◽  
Different Types ◽  
Cake Removal

The well clean-up process involves the removal of impermeable filter cake from the formation face. This process is essential to allow the formation fluids to flow from the reservoir to the wellbore. Different types of drilling fluids such as oil- and water-based drilling fluids are used to drill oil and gas wells. These drilling fluids are weighted with different weighting materials such as bentonite, calcium carbonate, and barite. The filter cake that forms on the formation face consists mainly of the drilling fluid weighting materials (around 90%), and the rest is other additives such as polymers or oil in the case of oil-base drilling fluids. The process of filter cake removal is very complicated because it involves more than one stage due to the compatibility issues of the fluids used to remove the filter cake. Different formulations were used to remove different types of filter cake, but the problem with these methods is the removal efficiency or the compatibility. In this paper, a new method was developed to remove different types of filter cakes and to clean-up oil and gas wells after drilling operations. Thermochemical fluids that consist of two inert salts when mixed together will generate very high pressure and high temperature in addition to hot water and hot nitrogen. These fluids are sodium nitrate and ammonium chloride. The filter cake was formed using barite and calcite water- and oil-based drilling fluids at high pressure and high temperature. The removal process started by injecting 500 ml of the two salts and left for different time periods from 6 to 24 h. The results of this study showed that the newly developed method of thermochemical removed the filter cake after 6 h with a removal efficiency of 89 wt% for the barite filter cake in the water-based drilling fluid. The mechanisms of removal using the combined solution of thermochemical fluid and ethylenediamine tetra-acetic acid (EDTA) chelating agent were explained by the generation of a strong pressure pulse that disturbed the filter cake and the generation of the high temperature that enhanced the barite dissolution and polymer degradation. This solution for filter cake removal works for reservoir temperatures greater than 100 °C.

scholarly journals Laponite: a promising nanomaterial to formulate high-performance water-based drilling fluids

2020 ◽  
Author(s):  
Xian-Bin Huang ◽  
Jin-Sheng Sun ◽  
Yi Huang ◽  
Bang-Chuan Yan ◽  
Xiao-Dong Dong ◽  
...  
Keyword(s):  
High Performance ◽  
Drilling Fluid ◽  
Nitrogen Adsorption ◽  
Drill String ◽  
Wellbore Stability ◽  
Fluid Loss ◽  
Drilling Fluids ◽  
Mechanism Analysis ◽  
Water Based ◽  
Inhibition Performance

Abstract High-performance water-based drilling fluids (HPWBFs) are essential to wellbore stability in shale gas exploration and development. Laponite is a synthetic hectorite clay composed of disk-shaped nanoparticles. This paper analyzed the application potential of laponite in HPWBFs by evaluating its shale inhibition, plugging and lubrication performances. Shale inhibition performance was studied by linear swelling test and shale recovery test. Plugging performance was analyzed by nitrogen adsorption experiment and scanning electron microscope (SEM) observation. Extreme pressure lubricity test was used to evaluate the lubrication property. Experimental results show that laponite has good shale inhibition property, which is better than commonly used shale inhibitors, such as polyamine and KCl. Laponite can effectively plug shale pores. It considerably decreases the surface area and pore volume of shale, and SEM results show that it can reduce the porosity of shale and form a seamless nanofilm. Laponite is beneficial to increase lubricating property of drilling fluid by enhancing the drill pipes/wellbore interface smoothness and isolating the direct contact between wellbore and drill string. Besides, laponite can reduce the fluid loss volume. According to mechanism analysis, the good performance of laponite nanoparticles is mainly attributed to the disk-like nanostructure and the charged surfaces.

Evaluation of Constitutive Equation for Stress in Solids in Porous Media Composed of Bridging Agents Used in Drilling Fluids

2012 ◽  
Vol 727-728 ◽  
pp. 1878-1883 ◽  
Author(s):  
Bruno Arantes Moreira ◽  
Flávia Cristina Assis Silva ◽  
Larissa dos Santos Sousa ◽  
Fábio de Oliveira Arouca ◽  
João Jorge Ribeiro Damasceno
Keyword(s):  
Porous Media ◽  
Constitutive Equation ◽  
Filter Cake ◽  
Drilling Fluid ◽  
Fluid Loss ◽  
Drilling Fluids ◽  
Oil Well ◽  
Well Drilling ◽  
Drilling Operations ◽  
The Stability

During oil well drilling processes in reservoir-rocks, the drilling fluid invades the formation, forming a layer of particles called filter cake. The formation of a thin filter cake and low permeability helps to control the drilling operation, ensuring the stability of the well and reducing the fluid loss of the liquid phase in the interior of the rocks. The empirical determination of the constitutive equation for the stress in solids is essential to evaluate the filtration and filter cake formation in drilling operations, enabling the operation simulation. In this context, this study aims to evaluate the relationship between the porosity and stress in solids of porous media composed of bridging agents used in drilling fluids. The concentration distribution in sediments was determined using a non-destructive technique based on the measure of attenuated gamma rays. The procedure employed in this study avoids the use of compression-permeability cell for the sediment characterization.

scholarly journals Transient response of near-wellbore supercharging during filter cake growth

2021 ◽  
Vol 76 ◽  
pp. 46
Author(s):  
Tianshou Ma ◽  
Nian Peng ◽  
Ping Chen ◽  
Yang Liu
Keyword(s):  
Pore Pressure ◽  
Filter Cake ◽  
Early Stage ◽  
Drilling Fluid ◽  
Reduction Rate ◽  
Time Dependent ◽  
Low Permeability ◽  
Drilling Fluids ◽  
Dynamic Filter ◽  
Cake Porosity

Supercharging in the vicinity of a borehole is an important factor that affects formation damage and drilling safety, and the filter cake growth process has a significant impact on supercharging in the vicinity of the borehole. However, existing models that predict pore pressure distribution overlook dynamic filter cake growth. Thus, an analytical supercharging model was developed that considers time-dependent filter cake effects, and this model was verified using a two-dimensional numerical model. The influences of filter cake, formation, and filtrate properties on supercharging were investigated systematically. The results indicate that time-dependent filter cake effects have significant influence on supercharging. Supercharging increases in the early stage but decreases over time because of the dynamic growth of filter cake, and the supercharging magnitude decreases along the radial direction. Because of filter cake growth, the magnitude of supercharging falls quickly across the filter cake, and the decreased magnitude of pore pressure caused by the filter cake increases. Supercharging in low-permeability formations is more obvious and the faster rate of filter cake growth, a lower filtrate viscosity and faster reduction rate of filter cake permeability can help to weaken supercharging. The order of importance of influencing factors on supercharging is overbalance pressure > formation permeability > formation porosity ≈ filtrate viscosity > filter cake permeability attenuation coefficient > initial filter cake permeability control ratio > filter cake growth coefficient > filter cake porosity. To alleviate supercharging in the vicinity of the borehole, adopting drilling fluids that allow a filter cake to form quickly, optimizing drilling fluid with a lower filtrate viscosity, keeping a smaller overbalance pressure, and precise operation at the rig site are suggested for low-permeability formations during drilling.

Innovative Surfactant Chemistry Offers the Performance Advantages to Invert Emulsion Drilling Fluids While Drilling Under Challenging Environments

2021 ◽  
Author(s):  
Arvindbhai Patel ◽  
Anil Kumar Singh ◽  
Nikhil Bidwai ◽  
Sakshi Indulkar ◽  
Vivek Gupta
Keyword(s):  
Sea Water ◽  
Drilling Fluid ◽  
Water Soluble ◽  
Performance Criteria ◽  
Drilling Fluids ◽  
Treatment Situation ◽  
Invert Emulsion ◽  
Wetting Agents ◽  
Pre Treatment ◽  
High Level

Abstract Stable invert emulsion with oil wet solids is achieved using invert emulsifiers and wetting agents. This paper reviews the chemistry and performance criteria of traditional invert emulsifiers and wetting agents utilized in formulating stable invert emulsion drilling fluids. However, occasionally such stable invert emulsion drilling fluids can be destabilized due to various hostile conditions encountered during drilling operation, and can adversely impact the drilling cost. Extreme preventive measures cannot avoid such hostile conditions such as sudden water influx, excessive solids and salt contaminations during drilling. Upon solids becoming extremely water wet with "flipped emulsion", it becomes impossible to fix the drilling fluid, resulting in expensive maneuver. Often situation cannot be corrected with traditional wetting agents and emulsifiers even at high level of treatments. New innovative chemistry addresses the severe water-wetting and emulsion instability of invert emulsion under extreme challenging and hostile situations. The unique water soluble oil mud conditioner (OMC) synergistically enhances the performances of traditional oil-wetting agents and emulsifiers at very low, as little as 0.5 ppb levels of treatment. This OMC improves and extends the efficacy of the traditional invert emulsifiers and oil wetting agents resulting in reduced usage of these additives with excellent economic advantages. The 15.0 ppg, invert emulsion drilling fluids were prepared using 2-3 ppb of primary and secondary emulsifiers, and these fluids were destabilized using high shear mixer for 7-8 hours. The destabilized fluids had severe water wet solids and ES value of less than 5. These destabilized fluids, upon treating with 0.5 ppb of newly developed OMC instantly became oil-wet and shiny and ES was increased to greater than 500. To demonstrate the effectiveness of OMC in pre-treatment situation, the base fluids treated with 0.5 −1.0 ppb of OMC showed superior mud stability compared to base fluid when contaminated with sea water, fine solids, barite and high salt contaminations. The OMC is flexible in its application and can be used as pre-treatment to improve the overall performance of drilling fluids and can also be used for post-treatment to recover the drilling fluids, which have been rendered unusable.

Sign in / Sign up

Export Citation Format

Share Document