Modification of Nanoclay Systems: An Approach to Stabilizing Drilling Fluids

2013 ◽  
Vol 829 ◽  
pp. 818-824
Author(s):  
Sahar Kafashi ◽  
Ramin Taghdimi ◽  
Gholamreza Karimi

This study was aimed to investigate the rheological properties and the possibility of nano(Na, Ca )- bentonites nanoproducts to meet the required drilling mud properties. Sepiolite (Sp) and the mixture of 2% nanoNaB with 1% Sp were collected and prepared from Irans oil Company (NIOC). The nanoclay performance evaluation involved the experimental tests of the rheological properties, filtration and gel strength. According to the results obtained from flow properties tests for the mixture, it was indicated that the mixture was not adequate to be a suitable drilling fluid. The main objective was to make stable dispersions with nanobentonite and sepiolite by using a water soluble polymer as stabilizer. The changes in the rheological properties of bentonite were investigated at various concentrations of polyvinyl alcohol (PVA) to discover the stability of the dispersions. The standard API tests were applied for drilling fluid to determine the properties of dispersions.

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jinliang Liu ◽  
Fengshan Zhou ◽  
Fengyi Deng ◽  
Hongxing Zhao ◽  
Zhongjin Wei ◽  
...  

Abstract Most of bentonite used in modern drilling engineering is physically and chemically modified calcium bentonite. However, with the increase of drilling depth, the bottom hole temperature may reach 180 °C, thus a large amount of calcium bentonite used in the drilling fluid will be unstable. This paper covers three kinds of calcium bentonite with poor rheological properties at high temperature, such as apparent viscosity is greater than 45 mPa·s or less than 10 mPa·s, API filtration loss is greater than 25 mL/30 min, which are diluted type, shear thickening type and low-shear type, these defects will make the rheological properties of drilling fluid worse. The difference is attributed to bentonite mineral composition, such as montmorillonite with good hydration expansion performance. By adding three kinds of heat-resistant water-soluble copolymers Na-HPAN (hydrolyzed polyacrylonitrile sodium), PAS (polycarboxylate salt) and SMP (sulfomethyl phenolic resin), the rheological properties of calcium bentonite drilling fluids can be significantly improved. For example, the addition of 0.1 wt% Na-HPAN and 0.1 wt% PAS increased the apparent viscosity of the XZJ calcium bentonite suspension from 4.5 to 19.5 mPa·s at 180 °C, and the filtration loss also decreased from 20.2 to 17.8 mL.


2021 ◽  
Vol 58 (2) ◽  
pp. 121-126
Author(s):  
R. M. Farag ◽  
A. M. Salem ◽  
A. A. El-Midany ◽  
S. E. El-Mofty

Abstract Invasion of fluids into porous media during drilling can lead to irreparable damage and reduced well productivity. Hence, minimizing the filtration loss of the drilling fluid into the formation is very important. The stability of colloidal suspensions plays a crucial role in controlling the interfacial forces and consequently on minimizing the filtration. The zeta potential is an indicator of the stability of colloids with respect to their electrostatic interactions. In this study, the rheological properties of bentonite suspensions are investigated with and without additives. The starch and CMC were used as additives to enhance the rheological properties of bentonite. The effects of these additives on the drilling fluid filtration were examined. Zeta-potential, viscosity, gel strength and yield point were measured to characterize the extent to which control of the filtration loss of the drilling fluids can be achieved. The zeta-potential and the amount of filtration loss of water-bentonite suspensions were correlated. Finally, the results showed that the addition of either starch or carboxymethyl cellulose (CMC) enhances the filtration properties of water-bentonite suspensions.


2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Feng-shan Zhou ◽  
Ting-ting Wang ◽  
Zheng-qiang Xiong ◽  
Wen-yue Guo ◽  
Xi Xiang ◽  
...  

An oil-in-water nanomicron wax emulsion with oil phase content 45 wt% was prepared by using the emulsifying method of surfactant-in-oil. The optimum prepared condition is 85°C, 20 min, and 5 wt% complex emulsifiers. Then the abovementioned nanomicron emulsifying wax was immersed into a special water-soluble polymer in a certain percentage by the semidry technology. At last, a solidified self-dispersed nanomicron emulsified wax named as Ewax, a kind of solid lubricant for water based drilling fluid, was obtained after dried in the special soluble polymer containing emulsifying wax in low temperature. It is shown that the adhesion coefficient reduced rate(ΔKf)is 73.5% and the extreme pressure (E-P) friction coefficient reduced rate(Δf)is 77.6% when the produced Ewax sample was added to fresh water based drilling fluid at dosage 1.0 wt%. In comparison with other normal similar liquid products, Ewax not only has better performances of lubrication, filtration loss control property, heat resistance, and tolerance to salt and is environmentally friendly, but also can solve the problems of freezing in the winter and poor storage stability of liquid wax emulsion in oilfield applications.


2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Issham Ismail ◽  
Nur Suriani Mamat ◽  
Baihaqi Mamat ◽  
Ahmad Shamsulizwan Ismail ◽  
Azmi Kamis ◽  
...  

An underbalanced drilling using foam drilling fluid is one of the most effective solutions which are capable of preventing formation damage, differential sticking, or circulation lost. Nevertheless, the limitation of using foam drilling fluid is the stability of its rheological properties which would affect its lubricity characteristics. Therefore, a research study was carried out to determine the stability and effectiveness of water soluble polymers as an additive in foam drilling fluid. To produce the required and most stable foam, four types of surfactants had been tested, namely sodium dodecyl sulfate (anionic), cetyltrimethylammonium bromide (cationic), T×100 (non ionic), and n-alkyl betaines (amphoteric). Then, the water soluble polymers, namely xanthan gum, hydroxyethyl cellulose, guar gum, and carboxymethyl cellulose, were evaluated as a stabilizer in the said foam drilling fluid. The laboratory works involved lubricity and rheological properties tests, which were conducted at ambient condition. The experimental results showed that the use of xanthan gum with anionic surfactant produced the most stable foam drilling fluid compared to other polymers. Rheological properties of the polymer foam drilling fluid were compared with water-based mud, and it was revealed that polymer foam drilling fluid could perform as effective as the latter. The significant advantage of using polymer foam drilling fluid was its coefficient of friction which was found to be lower than the water-based mud. 


2020 ◽  
Vol 4 (2) ◽  
pp. 18
Author(s):  
Bayan Qadir Sofy Hussein ◽  
Khalid Mahmood Ismael Sharbazheri ◽  
Nabil Adiel Tayeb Ubaid

The rheological properties of drilling fluids have an important role in providing a stable wellbore and eliminating the borehole problems. Several materials including polymers (xanthan gum) can be used to improve these properties. In this study, the effect of the local Katira, as a new polymer, on the rheological properties of the drilling fluids prepared as the bentonite-water-based mud has been investigated in comparison with the conventional xanthan gum. Experimental work was done to study of rheological properties of several gums such as, local katira gum, and xanthan gum bentonite drilling mud. Different samples of drilling fluids are prepared adding the xanthan gum and local katira to the base drilling fluid at different concentrations using Hamilton Beach mixer. The prepared samples are passed through rheological property tests including the apparent viscosity, plastic viscosity, and yield point (YP) under different temperature conditions. The obtained results show that the viscosity is increased from 5 to 8.5 cp and YP is increased from 18.5 to 30.5 lb/100 ft2, with increasing the concentration of the xanthan gum from 0.1 to 0.4. However, the effect of the local katira in increasing the viscosity and YP is lower compared with the xanthan gum, which are ranged between 5–6 cp and 18.5–20.5 cp.


2014 ◽  
Vol 641-642 ◽  
pp. 447-450 ◽  
Author(s):  
Long Li ◽  
Xu Bo Yuan ◽  
Cha Ma ◽  
Rong Chao Cheng ◽  
Yu Ping Yang

A new type of humic acid acetamide FLHA was synthesized by chemical modification of humic acid with long chain fatty amine, and the effect of humic acid acetamide on the rheological properties of gas-to-liquid (GTL) based drilling fluids was investigated. The results indicated that FLHA had good capacity of filtration reduction under 150 °C. Moreover, FLHA can improve the stability of GTL-based drilling fluids. As a result, FLHA is an good fluid loss additive for GTL-based drilling fluids, and it can optimizate drilling fluid system formulation to make drilling fluids have good rheological properties, filtration properties and environmental protection function.


2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Arild Saasen

Controlling the annular frictional pressure losses is important in order to drill safely with overpressure without fracturing the formation. To predict these pressure losses, however, is not straightforward. First of all, the pressure losses depend on the annulus eccentricity. Moving the drillstring to the wall generates a wider flow channel in part of the annulus which reduces the frictional pressure losses significantly. The drillstring motion itself also affects the pressure loss significantly. The drillstring rotation, even for fairly small rotation rates, creates unstable flow and sometimes turbulence in the annulus even without axial flow. Transversal motion of the drillstring creates vortices that destabilize the flow. Consequently, the annular frictional pressure loss is increased even though the drilling fluid becomes thinner because of added shear rate. Naturally, the rheological properties of the drilling fluid play an important role. These rheological properties include more properties than the viscosity as measured by API procedures. It is impossible to use the same frictional pressure loss model for water based and oil based drilling fluids even if their viscosity profile is equal because of the different ways these fluids build viscosity. Water based drilling fluids are normally constructed as a polymer solution while the oil based are combinations of emulsions and dispersions. Furthermore, within both water based and oil based drilling fluids there are functional differences. These differences may be sufficiently large to require different models for two water based drilling fluids built with different types of polymers. In addition to these phenomena washouts and tool joints will create localised pressure losses. These localised pressure losses will again be coupled with the rheological properties of the drilling fluids. In this paper, all the above mentioned phenomena and their consequences for annular pressure losses will be discussed in detail. North Sea field data is used as an example. It is not straightforward to build general annular pressure loss models. This argument is based on flow stability analysis and the consequences of using drilling fluids with different rheological properties. These different rheological properties include shear dependent viscosity, elongational viscosity and other viscoelastic properties.


2021 ◽  
Author(s):  
Emmanuel Ayodele ◽  
David Ekuma ◽  
Ikechukwu Okafor ◽  
Innocent Nweze

Abstract Drilling fluid are complex fluids consisting of several additives. These additives are added to enhance and control the rheological properties (such as viscosity, gel strength and yield point) of the mud. These properties are controlled for effective drilling of a well. This research work is focused on determining the rheological behavior of drilling mud using industry-based polymer and Irvingia Gabonensis (ogbono) as viscosifiers. Water based muds were formulated from the aforementioned locally sourced viscosifier and that of the conventional used viscosifier (Carboxylmetyl cellulose, CMC). Laboratory tests were carried out on the different muds formulated and their rheological properties (such as yield stress, shear stress, plastic viscosity and shear rate) are evaluated. The concentration of the viscosifiers were varied. The expected outcome of the research work aims at lowering the total drilling cost by reducing the importation of foreign polymer which promotes the development of local content in the oil and gas industry. The research compares the rheology of mud samples and the effect of varying the concentration (2g, 4g, 6g, 8g, and 10g) of both CMC and Ogbono and determining the changes in their rheological properties. The total volume of each mud sample is equivalent to 350ml which represent one barrel (42gal) in the lab. From the result, at concentration of 2g, the ogbono mud has a better rheology than the CMC mud, but at a concentration above 2g, CMC mud shows a better rheology than ogbono mud, that is, as the concentration of CMC is increased, the rheological properties of the mud increased while as the concentration of ogbono is increased the rheological properties decreased. The viscosity of the drilling fluid produced from the ogbono were lower than that of CMC, it could be used together with another local product such as cassava starch, offor or to further improve the rheology and then be a substitute to the conventional viscosifiers.


2021 ◽  
Author(s):  
Mehrdad Gharib Shirangi ◽  
Roger Aragall ◽  
Reza Ettehadi ◽  
Roland May ◽  
Edward Furlong ◽  
...  

Abstract In this work, we present our advances to develop and apply digital twins for drilling fluids and associated wellbore phenomena during drilling operations. A drilling fluid digital twin is a series of interconnected models that incorporate the learning from the past historical data in a wide range of operational settings to determine the fluids properties in realtime operations. From several drilling fluid functionalities and operational parameters, we describe advancements to improve hole cleaning predictions and high-pressure high-temperature (HPHT) rheological properties monitoring. In the hole cleaning application, we consider the Clark and Bickham (1994) approach which requires the prediction of the local fluid velocity above the cuttings bed as a function of operating conditions. We develop accurate computational fluid dynamics (CFD) models to capture the effects of rotation, eccentricity and bed height on local fluid velocities above cuttings bed. We then run 55,000 CFD simulations for a wide range of operational settings to generate training data for machine learning. For rheology monitoring, thousands of lab experiment records are collected as training data for machine learning. In this case, the HPHT rheological properties are determined based on rheological measurement in the American Petroleum Institute (API) condition together with the fluid type and composition data. We compare the results of application of several machine learning algorithms to represent CFD simulations (for hole cleaning application) and lab experiments (for monitoring HPHT rheological properties). Rotating cross-validation method is applied to ensure accurate and robust results. In both cases, models from the Gradient Boosting and the Artificial Neural Network algorithms provided the highest accuracy (about 0.95 in terms of R-squared) for test datasets. With developments presented in this paper, the hole cleaning calculations can be performed more accurately in real-time, and the HPHT rheological properties of drilling fluids can be estimated at the rigsite before performing the lab experiments. These contributions advance digital transformation of drilling operations.


Sign in / Sign up

Export Citation Format

Share Document