Mud System Research Articles

The results of laboratory testing and analysis of the use of a cationic drilling mud system in the construction of wells by sidetracking in the fields of Western Siberia

The results of laboratory testing and analysis of the use of a cationic drilling mud system in the construction of wells by sidetracking in the fields of Western Siberia

Analisa Perancanaan Lumpur Pemboran Menggunakan HPEBM pada Sumur "E" Lapangan "P"

The “E” well to be drilled is a development well in the “P” field located in the North Sumatra Basin. During the drilling operation in well “E” using HPWBM, HPWBM is used to overcome shale instability. This water-based mud is used because it is cheaper and more economical than using oil-based mud. However, this mud needs to be added with other chemicals because HPWBM has a weakness in controlling shale formation. The mud system design for the “E” well uses the offset well method, which uses data from nearby wells for comparison. Well “E” is divided into two intervals. Hole interval 12 1/4" with 9 5/8" casing from 24 m to 290 m depth using HPWBM. Then proceed with 8 1/2" hole intervals with 7" casing from 290 m to 530 m depth using the same mud. The problem this well will face is pressure at a depth of 500 m, thus increasing the mud density from 12 ppg to 14 ppg to prevent kick.

Looking into the Reservoir: Performance Evaluation of Fractured Long Horizontal Wells Using of Borehole Imaging Logs

Field G is a highly fractured and faulty field, this paper is seeking about the necessity to keep running Image logs in new oil wells and how the interpretation of the results would led the team to completing wells optimally and to design our well completion properly to prevent high initial water cut. Learnings are summarized from 40+ image logs ran in this field over the last few years. A cross field G seismic interpretation confirmed on lapping reservoirs and 3 major fault trends with different transmissibility. Also, sseismic and sub seismic Faults and fractures are confirmed from BHI with a NE-SW strike of field G and can be possibly related to production behavior of some wells. In 2015, field G Water Encroachment Study was conducted to identify the cause of high initial water cut of producers. It proposed that detecting fractures early via under-balanced drilling, Borehole Imaging Tools (BHI) and sealing the conduits with production packers would help reduce initial water-cuts [2]. BHI tools are open hole tools that measure either electrical conductivity of the borehole wall or the sonic travel time and amplitude. Micro-conductivity or amplitude and travel time measurements generate an image that shows bedding, fractures and many other fine-scale features. Acoustic tools are preferred in Oil Based Mud (OBM) system and hence they have not been used in field G to the extent that it required a dedicated discussion.

Desain Formulasi Lumpur Untuk Pemboran Panas Bumi Di Sumur GG-01

During the drilling process, we need to look at several aspects that need to be considered, including the drilling mud aspect which is one of the important aspects in a safe and efficient drilling process.The success of a drilling process through various rock layers is very dependent on the design of the drilling mud formulation. All of that can be influenced by the nature and physics of the drilling mud which needs to be adjusted to the formation conditions, formation pressure, rock type and fluid content contained in the formation. In designing the mud formulation that will be used, it can be done by using the mud system correlation method or by analyzing the pressure wells that become offset wells or key wells which are analyzed to determine the properties of the mud to be used. Well GG – 01 is an exploration well so it does not have an offset well. The drilling that will be penetrated is as many as 4 routes which in the first route the hole is made using a mash system so that it does not use drilling mud. And for the next route, the type of mud to be used is KCL Polymer with a different percentage on each route.

Preparation and application of an environmentally friendly compound lubricant based biological oil for drilling fluids

As the basic raw material of bio-oil based eco-friendly lubricant, a special selected by-product vegetable acidified oil (AO) was modified by vulcanization, esterification, or vulcanization followed by esterification. The optimized vulcanization process conditions are 1% sulfur powder catalyzed, temperature 130 ℃, reaction time 2 h, while the optimized esterification process requires 20% glycerol and 1% H2SO4 catalysis, reaction temperature 220 ℃, reaction time 3 h. We compounded modified AO, diluent, pour point depressant and emulsifier into an advanced drilling lubricant F-1. F-1 has excellent performances in bentonite drilling fluids, the extreme pressure lubrication coefficient reduction rate (Δf) in fresh water mud is 86.84%, and 85.76% in 4% NaCl salt water mud. After aging at 150 ℃ for 16 h, its Δf is improved compared with room temperature. Adding F-1 to the basic bentonite mud system, the filtration loss of drilling fluids decreased from 10 mL to 6.5 mL, the apparent viscosity and plastic viscosity experienced little change before and after aging. The new bio-oil compound lubricant has an excellent temperature resistance, a high salt contamination resistance and cost-effective. Vulcanization and esterification processes help to improve the lubricity and reduce foaming rates.

Investigation of Mud Related Wellbore Problems in Drilling Well-A in the Niger Delta Region

Wellbore instabilities due to mud related issues during well construction in the wetland Niger Delta region were analyzed, reviewing well A as a case study. Time distribution plots and activity break down summary were evaluated for the candidate well. From the analyses, drill bit and bottom hole assembly balling, largely due to soft sticky and reactive gumbo shale with high swelling and dispersive tendencies in the mud system, severe down hole losses, hole pack off, pipe stuck potentials and kicks are some likely mud related challenges often encountered drilling in the Niger Delta region. Consequent upon which there would be reduced rate of penetration, tight spot, increased torque and drag, as seen in well-A. The drilling fluids play pivotal roles in oil extraction processes as their type; design and formulation determine the ultimate success of the entire drilling operation and overall production performance of the well. A poorly designed mud system may trigger wellbore instability that could lead to non-productive time, loss of drilling equipment, even loss of the entire well, kick and blowout scenarios due to loss of primary and secondary barriers. Formation damage may occur, which ultimately leads to reduction in permeability and poor well performance,

Modified Corn Starch as an Environmentally Friendly Rheology Enhancer and Fluid Loss Reducer for Water-Based Drilling Mud

SummaryDrilling fluid rheology and fluid loss property are fundamental parameters that dictate the effectiveness and easiness of a drilling operation. Maintaining these parameters under high temperatures is technically challenging and has been an exciting research area for the drilling industry. Nonetheless, the use of drilling mud additives, particularly synthetic polymers, threaten ecological environments. Herein, modified corn starch (MCS) was synthesized, characterized, and investigated as an environmentally friendly rheology enhancer and filtration loss controlling agent for water-based mud (WBM) at high temperatures. The experimental results indicated that MCS exhibits better performance in improving rheological properties and fluid loss controlling ability for WBM than the commonly used mud additives. With the addition of an optimal concentration (0.3 wt%), MCS improved the rheology and fluid loss behavior of WBM formulation at harsh aging temperature (220°C) by practically 4 times and 1.7 times, respectively. The MCS was revealed to perform superbly over polyanionic cellulose (PAC) addition at all investigated temperatures. The better performance of the MCS was ascribed to the improved entanglements in the mud system owing to the additional hydroxyl (OH) groups. Besides, the Herschel-Bulkley model was found to be a constitutive model that described the rheological properties of the investigated muds satisfactorily. Moreover, the MCS was found to exhibit acceptable biodegradability properties.

Experimental Evaluation of Locally Synthesized Biodiesel Drilling Fluid

Diesel oil has been the preferred base fluid for the formulation of oil-based drilling mud. Diesel oil has negative effects on the environment and there is a growing need for more environmentally sustainable alternatives that can be technically compared to diesel base oil. In recent times, the use of vegetable oils as drilling fluid base oil has been of interest. In this study, 1378 kg/m3 of palm kernel oil-based mud (PKOBM) and palm kernel oil biodiesel based mud (BDBM) were experimentally formulated. BDBM was synthesized by the transesterification of vegetable (palm kernel) oil. The performance of PKOBM and BDBM was then evaluated against conventional diesel oil-based mud (DOBM). The evaluation performed was based on the rheological, filtration and wall building properties, emulsion and thermal stabilities, and acute toxicity of the formulated drilling fluid systems. The results obtained from the study reveal that the mud systems (PKOBM and BDBM) show a typical Herschel-Bulkley (modified power-law) drilling mud rheological pattern at temperatures of 49°C, 66°C and 80°C. BDBM showed comparable rheological properties with better hole cleaning capacity as indicated by a lower flow index. For the filtrate loss test, BDBM exhibited a slightly lower filtrate loss compared to DOBM, whereas PKOBM had a higher fluid loss of 4.4 ml. For the filter cake and thermal stability test, there were no significant changes between DOBM and BDBM, whereas PKOBM had the least desirable performance. BDBM exhibited the most stable emulsion of 1274 volts breaking voltage and PKOBM, the least with 739 volts compared to 1169 volts breaking voltage of DOBM. This study concludes that BDBM could be used as an environmentally sustainable substitute for diesel oil-based mud (DOBM).

Experimental evaluation of Sarcosine as an eco-friendly green hydrate inhibitor for the drilling of gas hydrate bearing formations

The hydrate inhibitors played a significant role in preventing hydrate formation in the drilling fluid systems. However, the disposal of these inhibitors was the primary concern for the drilling industries, as Thermodynamic Hydrate Inhibitors (THIs) are not eco-friendly, and Kinetic Hydrate Inhibitors (KHIs) are troublesome to dispose of due to their long polymeric structures. Hence, an attempt had been made to evaluate the Sarcosine, an amino acid, as a biodegradable, green hydrate inhibitor for water-based drilling fluid systems. Initial screening of Sarcosine in the THF-water hydrate (structure-II) system showed that it behaved as a zwitterionic, dual-function inhibitor. It had better inhibition characteristics in delaying induction time and improving rheological and filtration properties than PVCap and PVP while used in formulated mud compositions. The water-based mud used in this work was prepared by mixing carboxymethyl cellulose (CMC), polyanionic cellulose (PAC), xanthan gum (XG), and potassium chloride (KCl) with distilled water. For Sarcosine content water-based mud systems, coefficients of determination (R2) values were dependable, while low-temperature (2 C) rheological values were fitted in Herschel-Bulkley model. These experimental investigations showed that the Sarcosine might be used for the drilling of gas hydrate-bearing formations.

Development and Application of the 3D Model Test System for Water and Mud Inrush of Water-Rich Fault Fracture Zone in Deep Tunnels

In order to study the evolution process, damage characteristics, and occurrence mechanism of water and mud inrush disaster in deep tunnel fault zone with infiltration instability under complex conditions, a set of the three-dimensional physical model test systems of water and mud inrush flow-solid coupling in tunnel fault zones is developed. The system mainly comprises a rigid test frame, ground stress loading system, hydraulic loading system, multiple information monitoring and acquisition system, and mud and water protrusion recovery system. The system’s main features are that it can meet the model’s simulation of the ground stress field, water pressure, and other complex environments subjected to ground stress, and water pressure gradients can be controlled. The system is characterized by high rigidity, high-pressure strength, visualization, good sealing, and expandability. Taking the water fault zone of a well in the Dazhu Mountain Tunnel of the Darui Railway as the research object, the new fault zone and surrounding rock similar materials applicable to the flow-solid coupling model test are designed using the self-developed flow-solid coupling similar materials. The system is used for model tests to reveal the spatial and temporal changes of the surrounding rock stress field and seepage field during the tunnel excavation process. The test results show that the system is stable and reliable, and the research method and results are of guiding significance to the research of the same type of underground engineering.

The Effect of Biopolymer Chitosan on the Rheology and Stability of Na-Bentonite Drilling Mud.

The utilization of greens resources is a grand challenge for this century. A lot of efforts are paid to substitute toxic ingredients of the conventional drilling mud system with nontoxic natural materials. In this paper, the effect of the natural polymer chitosan on the rheology and stability of sodium-bentonite drilling mud was investigated in the polymer concentration range of 0.1–3.0 wt.%. Both the shear and time dependent rheological properties of pure chitosan, pure bentonite and bentonite–chitosan dispersions were studied. Moreover, zeta potential measurements were used to evaluate the stability of bentonite-chitosan suspension. Adding chitosan improved the natural properties of drilling mud, namely: yield stress, shear thinning, and thixotropy. The viscosity of bentonite suspension increased significantly upon the addition of chitosan in the concentration range of 0.5 to 3.0 wt.% forming network structure, which can be attributed to the interactions of hydrogen bonding between -OH clusters on the bentonite surface with the NH group in the chitosan structure. On the other hand, dispersed chitosan–bentonite suspension was observed at low chitosan concentration (less than 0.5 wt.%). Increasing both bentonite and chitosan concentrations led to the flocculation of the bentonite suspension, forming a continuous gel structure that was characterized by noteworthy yield stress. The desired drilling mud rheological behavior can be obtained with less bentonite by adding chitosan polymer and the undesirable effects of high solid clay concentration can be avoided.

Optimum Selection of H2S Scavenger in Light-Weight and Heavy-Weight Water-Based Drilling Fluids.

During hydrocarbon drilling operations, the presence of hydrogen sulfide (H2S) gas could cause serious health and safety issues. Scavenging this gas and eliminating its impact are essential requirements for a safe drilling operation. This study investigated the impact of three H2S scavenger additives (copper nitrate, iron gluconate, and potassium permanganate) on water-based drilling fluids (WBDFs). The additives were tested on two actual field drilling mud samples that differ mainly in their weight. The scavengers’ impact on drilling muds was investigated by measuring their scavenging capacity and their effect on rheology, fluid loss, and pH. Potassium permanganate outperformed the other scavengers when added to the lighter (lower density) WBDF. However, it did not impact the scavenging capacity of the heavier mud system. Copper nitrate outperformed the other scavengers in the heavier drilling mud system. Also, the addition of copper nitrate in the lighter mud system increased its H2S-scavenging capacity greatly, while for iron gluconate, it did not perform very well. Overall, all the scavenger-containing drilling muds did not have any significant harmful impact on the plastic viscosity or the fluid loss properties of the drilling muds. Furthermore, all the tested drilling mud samples showed an excellent ability to clean wellbores and suspend drill cuttings evident by the high carrying capacity with the exception of iron gluconate or potassium permanganate with the heavy mud system.

Investigation of filtration properties of a formate-based mud system under high temperature conditions

Using the methods of design of experiments, filtration properties of the bentonite-free mud system that contains xanthan gum, starch, sodium and potassium formate salts, calcium carbonate and Alevron agent at temperature range of 130–170 °C, differential pressure of 1–5 MPa and initial permeability of ceramic filters of 0.95–7.20 D were studied. Regression models were built for the НТНР filtration loss and permeability of a ceramic filter after mud cake build-up depending on mud additives concentrations, temperature, differential pressure and initial filter permeability, which provide high accuracy of experimental data approximation. • Regression models for НТНР filtration loss and permeability of mud cake. • Filtration properties of formate-based mud system. • Elaboration of formate-based mud optimal formulations for high-temperature drilling. • Filtration properties of drilling muds tested on ceramic disks of various pore sizes.

Effect of hybrid water-based mud on the improvement of wellbore stability: Kolosh Formation in Iraqi Kurdistan Region

Most important aspect of drilling clay-rich formations is preventing the hydration and dispersion. Oil based drilling muds (OBM) have historically been the first choice for drilling these kinds of formations, however the usage of the OBM is currently forbidden in drilling operation due to environmental issues. As an alternative, many inhibitive water-based muds were proposed. This paper describes the experimental work carried out on ten shale samples to evaluate stabilization of shale and clay-fluid interactions. After mineralogical analysis of shale samples, swelling and hot-rolling dispersion test were conducted using fresh water, polyamine, sodium silicate and oil base mud. Mineralogical analysis results showed that the cutting samples of 3, 4, 5, 6 and 7 have the highest clay content. Cation exchange capacity (CEC) results indicated that the shale sample with high concentration of smectite recorded the highest CEC value as it has the ability to absorb water into its inter-layers and exchange cations. When shale samples were tested in linear Swell meter, it is expressed the lower swelling percentage for oil base mud and maximum for fresh water. However, it was found out that both sodium silicate and polyamine mud systems yield the same performances. Furthermore, dispersion results showed that the shale recovery percentage increased from 16.3% to 56.2% when sodium silicate mud was used instead of polyamine mud. For the fresh water and oil base mud, results confirmed findings of linear swelling meter test, which is the lowest recovery for the fresh water (6.7%), and maximum recovery for the OBM (109.9%). The improved swelling inhibition suggested that sodium silicate mud could be effectively used to control wellbore instability while drilling through the Kolosh Formation .

Specific heat capacity of xanthan gum/PAC polymer-based drilling fluids: An experimental and correlation study

The accurate prediction of wellbore thermal profile is essential to ensure the success of any drilling operation. Currently, the heat capacity values used for predicting the thermal behavior of oil and gas wells assume the heat capacity of the drilling which leads to errors. Thus, determining the heat capacities of drilling mud systems would aid to efficiently predict the thermal distribution of wells. In this study, the heat capacities of fresh and aged mud samples of 0.8 wt% xanthan gum water-based mud and 0.8 wt% polyanionic cellulose (PAC) water-based mud and their blend system (0.4 wt% xanthan gum + 0.4 wt% PAC) were measured using a differential scanning calorimetry (DSC) from 5 to 100 °C. The new and aged samples represent testing the mud as fresh samples and over time (1–3 days). The result shows that the specific heat capacity values of the drilling muds differ from the heat capacity of water (which is generally used for drilling-related heat transfer modeling and simulations). High heat capacity values were observed for the 0.8 wt% xanthan gum mud system compared with the 0.8 wt% PAC mud system. However, the blend of 0.4 wt% xanthan gum + 0.4 wt% PAC exhibited the highest heat capacity values. In both fresh and aged samples, the heat capacity of 0.8 wt% xanthan gum mud was in the range of 3.805–4.287 J/g.oC. While 0.8 wt% PAC mud and 0.4 wt% xanthan gum + 0.4 wt% PAC mud system were within 0.7635–1.1329 J/g.oC, and 4.134–4.324 J/g.oC, respectively. These experimental heat capacity values are recommended for accurate oil & gas well heat transfer behavior modeling and simulation predictions and related studies.

Karotlu sondaj kulelerinde sorunlu formasyonlar için uygulanan çamur sistemleri

The two most important features of drilling rigs based on the core drilling principles are the drill set rotating at high speeds and the very precise spacing between the pipe and the well wall. Formation pieces that swell, flow into the well, spill or collapse during the drilling of problematic formations mix into the mud or narrow the annulus and cause well problems by restraining the rotation of the drill string and circulation. The spilled formation pieces cause an excessive solid material increase in the mud structure and due to the effect of centrifugal force, the solids adhere to the inner wall of the pipes near the surface and form a cake. Excessive cake thickness in the pipes obstruct the descent of the core barrel inner tube catcher into the well. During the removal of the inner tube, a vacuum occurs in the well due to the mud discharged from the rod and the problematic formations are poured into the annulus and block the core between the core barrel and the well wall. In this study, the performance of mud systems determined by trial and error method against the problems encountered in unconsolidated claystone, mudstone (shale), siltstone and sand - pebble stones in core coal exploration drillings in Çorum - Amasya region were evaluated. Monitoring and regular improvement of the rheological values of the mud compositions, changing the mud composition according to the well conditions, keeping the gel strength high and increasing its density with salt was found to play an important role in keeping the unconsolidated formations physically balanced. Salt mud also minimized the formation of cake in the pipe.

Development of an inhibitory drilling mud to reduce environmental pollution

During the drilling of oil and gas wells, drilling fluids are used to transport the drilled cuttings to the surface. The most commonly used drilling fluids are water-based with the addition of various polymers. Such mud systems are used not only for transporting cuttings, but also for drilling in unstable formations. When drilling clay rocks, they are hydrated and then dispersed, which leads to various accidents. Therefore, there is a need for the correct selection of the composition of the drilling fluid with high inhibitory properties. Since polymer solutions contain a large number of toxic chemical reagents, in order to reduce harm to the outside world, it is necessary to select a solution that performs all the necessary functions, but with a smaller amount of toxic chemical reagents. This paper discusses modern drilling fluids that are currently used in production, as well as developed new compositions of more environmentally friendly fluids.

Drilling waste management using zero discharge technology with Drill Cutting Re-injection (DCRI) method for environmental preservation

The energy requirement level in Indonesia is quite high. The increasing oil and gas upstream industries to fulfil energy requirement in the future is highly connected with the escalation of wastes, especially drilling wastes. Drilling is one of the main operations in upstream oil and gas industries, which can harm the environment with its various types of wastes. The drilling process produces millions of barrels of wastes each year. However, with the industries being rapidly developed to fulfil national energy requirement, environmental-related regulations for drilling activities have been firmly tightened. Drilling and drilling mud system technology is more sophisticated and the majority of oil drilling companies are starting to adopt environmentally friendly drilling options. The objective of writing this article is to acknowledge the method of drilling waste processing by considering environmentally friendly aspect. Drill Cutting Re-Injection (DCRI) is one of the developing environmentally friendly processing techniques with zero discharge in oil and gas industries. With the utilization of the DCRI process, the companies can produce positive outcomes such as low environmental impact, low safety risks, low transportation problems, and economically cleaning responsibility.

Utilizing A Dual Use Local Materials Instead of Imported Foreign Materials for Drilling Mud Conditioning

The most important constituents of drilling operation success is keeping the drillingfluid rheological properties within a certain limit to maintain continuity of theirfunctions in a good manner. To achieve that, the drilling mud system needs continuousand direct supervision such as measuring its rheological properties and treating anydeviation in their values. Viscosity is the most important property in hydraulic programsuccess due to its direct relation with a bottom hole cleaning during well drilling, thusrelated with the drilling rate, so this property should be kept essentially to ensurebottom hole cleaning and high drilling rate at the same time.Some chemicals should be added to the mud system to keep both viscosity and otherproperties within certain standards and the required limit ,the high cost of suchchemicals increase both the metric cost and the final cost of such wells.The aim of this research is to test the physical and chemical properties of a localmaterial, as a thinner and a filtration rate reducer, which tends to decrease therheological properties of drilling mud. Twenty six samples of different types of drillingmud are tested with both the local and imported foreign materials.The results for both additive materials are compared and it is found that the localthinner has the same trend as the foreign material to a certain extent. Also, in this work,the ideal rheological model is detected among six rheological models by preparing anexcel system program to determine the Average Absolute Percentage Error (AAPE).This program compares the calculated shear stress values and the measured valuesobtained from high pressure high temperature viscometer.The selected models are Bingham plastic model, Power law model, Modified powerlaw model, Robertson stiff model, and Modified Robertson stiff model and Cassonmodel.
 The most important constituents of drilling operation success is keeping the drillingfluid rheological properties within a certain limit to maintain continuity of theirfunctions in a good manner. To achieve that, the drilling mud system needs continuousand direct supervision such as measuring its rheological properties and treating anydeviation in their values. Viscosity is the most important property in hydraulic programsuccess due to its direct relation with a bottom hole cleaning during well drilling, thusrelated with the drilling rate, so this property should be kept essentially to ensurebottom hole cleaning and high drilling rate at the same time.Some chemicals should be added to the mud system to keep both viscosity and otherproperties within certain standards and the required limit ,the high cost of suchchemicals increase both the metric cost and the final cost of such wells.The aim of this research is to test the physical and chemical properties of a localmaterial, as a thinner and a filtration rate reducer, which tends to decrease therheological properties of drilling mud. Twenty six samples of different types of drillingmud are tested with both the local and imported foreign materials.The results for both additive materials are compared and it is found that the localthinner has the same trend as the foreign material to a certain extent. Also, in this work,the ideal rheological model is detected among six rheological models by preparing anexcel system program to determine the Average Absolute Percentage Error (AAPE).This program compares the calculated shear stress values and the measured valuesobtained from high pressure high temperature viscometer.The selected models are Bingham plastic model, Power law model, Modified powerlaw model, Robertson stiff model, and Modified Robertson stiff model and Cassonmodel.

A New Alternative Thinner in the Drilling Fluid System

The most important constituent of drilling operation success is keeping the drilling fluidrheological properties within a certain limit to maintain continuing their functions in a goodmanner. To achieve that, the drilling mud system needs continuous and direct supervision such asmeasuring its rheological properties and treating any deviation in their values. Viscosity is themost important property in hydraulic program success due to its direct relation with bottom holecleaning during drilling, thus related with the drilling rate, so this property should be keptbasically to ensure bottom hole cleaning and high drilling rate at the same time.Some chemicals such as thinner should be added to the mud system to keep both viscosity andother properties within certain standards and required limits; these materials have a high cost,increasing both the metric cost and the final cost of such well.The aim of this research is to test the physical and chemical properties for a local material, as athinner, which tends to decrease the rheological properties of drilling mud .Thirty nine samplesof different types of drilling mud are tested with both the native and foreign imported materials.The results for both additive materials are compared and concluded that the local thinner has thesame trend with the imported material to a certain limit.