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

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3361
Author(s):  
Basim Abu-Jdayil ◽  
Mamdouh Ghannam ◽  
Karam Alsayyed Ahmed ◽  
Mohamed Djama
Keyword(s):  
Yield Stress ◽  
Polymer Concentration ◽  
Grand Challenge ◽  
Drilling Mud ◽  
Gel Structure ◽  
Natural Properties ◽  
Clay Concentration ◽  
Bentonite Suspension ◽  
The Stability ◽  
Conventional Drilling

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.

scholarly journals Impact of organophilic clay on rheological properties of gasoil-based drilling muds

2020 ◽  
Vol 10 (8) ◽  
pp. 3533-3540
Author(s):  
Cheikh Bergane ◽  
Larbi Hammadi
Keyword(s):  
Shear Rate ◽  
Rheological Properties ◽  
Yield Stress ◽  
Drilling Mud ◽  
Flow Curves ◽  
Casson Model ◽  
Organophilic Clay ◽  
The Stability ◽  
Drilling Muds ◽  
The Impact

Abstract In this study, the impact of VG69 organophilic clay on the rheological properties of gasoil-based drilling muds (invert emulsions) was investigated. The flow curves of gasoil-based drilling muds as a function of the dose of VG69 organophilic clay were analyzed by the Casson model. The addition of VG69 organophilic clay with a quantity range between 0 and 5 g in gasoil-based drilling muds induces an increase in the yield stress and the viscosity at an infinite shear rate of drilling muds. It is also proven that the addition of VG69 organophilic clay leads to an increase in the viscoelastic and thixotropic properties of the drilling muds. The study of the stability of gasoil-based drilling muds by centrifugation showed that for a quantity of VG69 organophilic clay lower than 3 g, the stability of the drilling muds increases and for a quantity of VG69 organophilic clay higher than 3 g, their stability decreases. The results obtained showed that the addition of 3 g of VG69 organophilic clay to the gasoil-based drilling mud increased the yield stress by 230%, the viscosity at an infinite shear rate by 3.4% and it improved the mud stability by 70%.

Developing Stability of Posterior Mandibular Implants Placed With Osteotome Expansion Technique Compared With Conventional Drilling Techniques

2017 ◽  
Vol 43 (2) ◽  
pp. 131-138 ◽  
Author(s):  
Yen-Ting Lin ◽  
Adrienne Hong ◽  
Ying-Chin Peng ◽  
Hsiang-Hsi Hong
Keyword(s):  
Bone Density ◽  
Surgical Techniques ◽  
Primary Stability ◽  
Conventional Technique ◽  
Implant Stability ◽  
Implant Stability Quotient ◽  
Expansion Technique ◽  
The Stability ◽  
Conventional Drilling ◽  
Secondary Stability

Clinical decisions regarding the stability and osseointegration of mandibular implants positioned using the bone expansion techniques are conflicting and limited. The objective was to evaluate the stability of implants placed using 2 surgical techniques, selected according to the initial width of the mandibular posterior edentulous ridge, with D3 bone density, during a 12-week period. Fifty-eight implants in 33 patients were evaluated. Thirty-two implants in 24 patients were positioned using the osteotome expansion technique, and 26 fixtures in 17 patients were installed using the conventional drilling technique. The implant stability quotient values were recorded at weeks 0, 1, 2, 3, 4, 6, 8, 10, and 12 postsurgery and evaluated using analysis of variance, independent, and paired t tests. Calibrated according to the stability reading of a 3.3-mm diameter implant, the osteotome expansion group was associated with a lower bone density than the conventional group (64.96 ± 6.25 vs 68.98 ± 5.06, P = .011). The osteotome expansion group achieved a comparable primary stability (ISQb-0, P = .124) and greater increases in secondary stability (ISQb-12, P = .07) than did the conventional technique. A D3 quality ridge with mild horizontal deficiency is expandable by using the osteotome expansion technique. Although the 2 groups presented similar implant stability quotient readings during the study period, the osteotome expansion technique showed significant improvement in secondary stability. The healing patterns for these techniques are therefore inconsistent.

Rheological and Hydraulic Properties of Drilling, Completion, and Stimulation Fluids in Straight and Coiled Tubings

2002 ◽  
Author(s):  
Y. Zhou ◽  
S. N. Shah
Keyword(s):  
Drag Reduction ◽  
Guar Gum ◽  
Polymer Concentration ◽  
Hydroxyethyl Cellulose ◽  
Test Facility ◽  
Drilling Mud ◽  
Polymeric Fluids ◽  
Pressure Losses ◽  
Coiled Tubing ◽  
Friction Pressure

The rheological properties and friction pressure losses of several fluids that are most commonly used as well drilling, completion, and stimulation fluids have been investigated experimentally. These fluids include polymeric fluids – Xanthan gum, partially hydrolyzed polyacrylamide (PHPA), guar gum, and hydroxyethyl cellulose (HEC), bentonite drilling mud, oil-based drilling mud, and guar-based fracturing slurries. Rheological measurements using a Bohlin CS 50 rheometer and a model 35 Fann viscometer showed that these fluids exhibit shear thinning and thermal thinning behavior except the bentonite drilling mud whose viscosity increased as the temperature was raised. Flow experiments using a full-scale coiled tubing test facility showed that the friction pressure loss in coiled tubing is significantly higher than in straight tubing. Since the polymeric fluids displayed drag reducing property, their drag reduction behavior in straight and coiled tubings was analyzed and compared. It was found that the drag reduction (DR) in coiled tubing is much lower than that in straight tubing. Plots of drag reduction vs. generalized Reynolds number indicate that the drag reduction in coiled tubing was not affected by polymer concentration as much as in straight tubing. The onsets of turbulence and drag reduction in coiled tubing were significantly delayed as compared with straight tubing. The effect of solids content on the friction pressure losses in coiled tubing is also briefly discussed.

On the stability of Poiseuille flow of a Bingham fluid

1994 ◽  
Vol 263 ◽  
pp. 133-150 ◽  
Author(s):  
I. A. Frigaard ◽  
S. D. Howison ◽  
I. J. Sobey
Keyword(s):  
Yield Stress ◽  
Poiseuille Flow ◽  
Linear Instability ◽  
Bingham Fluid ◽  
Additional Parameter ◽  
Two Dimensional ◽  
Plane Poiseuille Flow ◽  
Bingham Number ◽  
The Stability ◽  
Drilling Muds

The stability to linearized two-dimensional disturbances of plane Poiseuille flow of a Bingham fluid is considered. Bingham fluids exhibit a yield stress in addition to a plastic viscosity and this description is typically applied to drilling muds. A non-zero yield stress results in an additional parameter, a Bingham number, and it is found that the minimum Reynolds number for linear instability increases almost linearly with increasing Bingham number.

A Tracked Robot for Complex Environment Detecting

2014 ◽  
Vol 670-671 ◽  
pp. 1389-1392
Author(s):  
Fan Wu ◽  
Shi Liu ◽  
Wen Jing Mu
Keyword(s):  
Control Function ◽  
Experimental Tests ◽  
Grand Challenge ◽  
Complex Environment ◽  
Wireless Location ◽  
Network Nodes ◽  
Target Capture ◽  
The Stability ◽  
Control Terminal ◽  
Detection Search

The complex geographical environment put forward grand challenge to most current detecting robot on the problem of communication control and moving obstacle avoidance.This paper proposed a crawler robot for complex environment detecting.Information acquisition was achieved by Labview programming,the collected sensor information was debugged by fusing and displaying in the Labview interface , in order to realize the stability of the system.The positioning part adopted wireless location technology of ZigBee networks,which can support a large number of network nodes, fast, and reliable security etc.In addition, the upper part of the robot body was equipped with camera and mechanical arm to achieve target capture, carrying something and other tasks. According to the situation of accident, remote control terminal through wireless control function can control the further action of the robot. Through experimental tests, this paper proposes this kind of detection robot had great advantages in detection, search and rescue, it can complete the search under complex and dangerous environment.

scholarly journals Simultaneous Operations of Pregrouting and Shaft Drilling in Shaft Construction

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Zhipeng Xu ◽  
Xuhai Feng ◽  
Shengsheng Li ◽  
Liming Fan ◽  
Changwu Liu
Keyword(s):  
Ground Improvement ◽  
Ground Vibration ◽  
Drilled Shaft ◽  
Residual Water ◽  
Drilling Mud ◽  
Construction Time ◽  
Sinking Rate ◽  
Simultaneous Operations ◽  
Technical Challenges ◽  
The Stability

In shaft construction, conducting shaft drilling and pregrouting simultaneously is expected to speed up the sinking rate and save the cost. Reasonable determination of the spatial locations of the drilled shaft and grouting holes and proper defining of the start time of each construction work are the crucial techniques. To smoothly execute the simultaneous operations, the bedrock to be grouted is divided into two sections. The upper bedrock is injected first using straight grouting holes to act as a tight cover to protect shaft drilling. Then, the lower formations are grouted using S-shaped grouting holes, which are performed simultaneously with shaft drilling. The construction time of simultaneous operations of pregrouting for the lower bedrock using S-shaped holes and shaft drilling is the saved time. The main technical challenges include the stability of grouting holes and safety of shaft walls, as well as the disposal of the contaminative waste drilling mud. The stability of grouting holes which might affect by the shaft drilling-induced ground vibration could be evaluated according to the penetration of ground vibration caused by TBM tunnelling. If the grouting hole is in the range of ground vibration, protective measures including casing and ground improvement should be utilized to ensure the stability of grouting holes. The stability of unlined walls of the drilled shaft caused by the increased groundwater pressure can be achieved by a tight cover between the drilled shaft and pregrouting holes. The thickness of the cover is actually the length of the straight holes. The cover should have sufficient thickness and impermeability, which can considerably reduce or even completely stop the increased groundwater pressure in vicinity of the drilled shaft. The thickness and permeability of the cover could be determined using Maag’s solution for penetration of grouts in porous media. On the other hand, the waste drilling mud with proper modifications can be reutilized to prepare clay-cement-like grouts, which could provide an eco-friendly and cheap solution to harmlessly treat the huge volume of waste drilling mud. The properties of waste drilling mud and behaviors of grouts prepared using the waste mud should be experimentally investigated before reutilization, owing to uncertainties of geology in various cases. The construction time using the simultaneous operation method is just about 60% of that of the traditional excavation method, and the low value of measured residual water inflow shows the reliability of reusing the waste drilling mud as grouting materials. The proposed method could virtually improve the shaft sinking rate and save the construction cost. The principles developed for these technical challenges have been proved to be applicable in practices, which are believed to strongly support the applicability of this new method in other cases.

scholarly journals Improvement of the Rheological and Filtration Properties of Drilling Mud Using the Syrian Clay

2020 ◽  
Vol 26 (5) ◽  
pp. 211-230
Author(s):  
Adnan Ibrahim Barodi
Keyword(s):  
Xanthan Gum ◽  
Drilling Fluid ◽  
Drilling Fluids ◽  
Drilling Mud ◽  
Clay Concentration ◽  
Fluid Properties ◽  
Drilling Operations ◽  
Solid Part ◽  
Time Required ◽  
Filtration Properties

Drilling fluid properties and formulation play a fundamental role in drilling operations. The Classical water-based muds prepared from only the Syrian clay and water without any additives((Organic and industrial polymers) are generally poor in performance. Moreover, The high quantity of Syrian clay (120 gr / l) used in preparing drilling fluids. It leads to a decrease in the drilling speed and thus an increase in the time required to complete the drilling of the well. As a result, the total cost of drilling the well increased, as a result of an increase in the concentration of the solid part in the drilling fluid. In this context, our study focuses on the investigation of the improvement in drilling mud   Prepared from the Syrian clay by reducing the clay concentration to (50 gr / L). And compensate for the remaining amount (70 gr / l) of clay by adding (natural and industrial polymers) The rheological properties and filtration are measured at different concentrations of polymers .. In light of the experiments, we determine the polymers' concentrations that gave good results in improving the flow properties and controlling the Filter. It is polymers that have given good results:، HEC، HEC and Xanthan Gum  PAC and HEC، CMCHV، PolyAcryl Amid ، Xanthan Gum .

scholarly journals INVESTIGATING BETANIN STABILITY, RELEASE PROFILE AND ANTIOXIDANT ACTIVITY OF ETHYL CELLULOSE MICROPARTICLE CONTAINING BEETROOT (BETA VULGARIS, LINN) EXTRACT

2021 ◽  
pp. 133-138
Author(s):  
ANITA SUKMAWATI ◽  
SETYO NURWAINI ◽  
UMI BUDI RAHAYU ◽  
APRILIANA P. C. WIDAWAN ◽  
ANITA SAFITRI ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Beta Vulgaris ◽  
Active Substance ◽  
Ethyl Cellulose ◽  
Encapsulation Efficiency ◽  
Polymer Concentration ◽  
Physical Characteristics ◽  
Release Profile ◽  
The Stability ◽  
Active Substances

Objective: The objective of this research is to evaluate the ability of ethyl cellulose (EC) microparticle to protect the beetroot (Beta vulgaris, Linn) active substance. In addition, this research also investigates the effect of polymer concentration during microparticle preparation toward physical characteristics of microparticle, release profile of betanin as well as antioxidant activity of microparticle. Methods: The microparticle was produced using the emulsification method using various concentrations of EC in the organic phase and beetroot extract as the active substances. The physical characterization was carried out including the imaging of microparticle using scanning electron microscope (SEM), zeta potential and encapsulation efficiency (EE). The stability test for an active substance in microparticle was carried out at temperature 40 °C for 28 d. The release profile was evaluated using the dissolution method and the antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH).Results: The result showed that the EC concentration strongly influenced the physical characteristics and EE of beetroot extract in microparticle. The microparticles also had good protection for betanin during storage. The release of active substance from microparticle following Higuchi kinetic. The highest antioxidant activity was found in the microparticle using EC 20%. Conclusion: The EC microparticle is the potential to protect the degradation of antioxidant substance from natural product. However, the physical properties, EE, the ability to prevent degradation of active substance, release rate and antioxidant activity, are strongly influenced by the EC polymer concentration during microparticle preparation.

Scaling Behavior in Electrohydrodynamic Jetting of Polymeric Solutions

2019 ◽  
Author(s):  
Abhishek K. Singh ◽  
Kaushlendra Dubey ◽  
Rajiv K. Srivastava ◽  
Supreet Singh Bahga
Keyword(s):  
Flow Rate ◽  
Flow Behavior ◽  
Polymer Concentration ◽  
Viscoelastic Behavior ◽  
Scaling Behavior ◽  
Jet Stability ◽  
Polymeric Solutions ◽  
Newtonian Liquids ◽  
The Stability ◽  
Viscoelastic Liquids

Abstract An electrohydrodynamic (EHD) jet forms when a leaky-dielectric liquid issuing out of a needle is accelerated and stretched by electrostatic forces. Stability and scaling behavior of the EHD jet of polymeric solutions depend on electrostatics, fluid mechanics and rheology of the liquid. While EHD jetting of Newtonian liquids have been described in the literature, the effect of non-Newtonian rheology on EHD jetting is still not well-understood. Therefore, we present a detailed experimental investigation of the stability and scaling behavior of EHD jets of polymeric solutions that exhibit non-Newtonian flow behavior. The stability of cone-jet was analyzed by varying flow rate, electric field and polymer concentration. Experiments were performed for polymeric solutions of polycaprolactone (PCL) dissolved in acetic acid. Our experiments show that non-Newtonian viscoelastic behavior can significantly alter the stability characteristics of the EHD jet. We have found that increase of elasticity of polymeric solutions results in enhanced jet stability. Finally, we present the dependence of experimentally measured diameter dj of the EHD jet on the flow rate Q. Experimentally measured diameter of the EHD jet scales as dj ∼ Q0.65 for both Newtonian and non-Newtonian viscoelastic liquids, which can be attributed to dominant inertia forces in our experiment.

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