Korelacja skuteczności działania środków dyspergujących o różnym mechanizmie upłynniania

Nafta-Gaz ◽  
2020 ◽  
Vol 76 (11) ◽  
pp. 816-826
Author(s):  
Marcin Kremieniewski ◽  
Keyword(s):  
Chemical Structure ◽  
Research Work ◽  
Rheological Parameters ◽  
Cement Slurry ◽  
Specific Group ◽  
Rheological Models ◽  
Dispersing Agent ◽  
Efficient Performance ◽  
Fluidizing Agent ◽  
Polymer Dispersant

Effective borehole sealing depends on many properties of the cement slurry. The rheological parameters are the most important. Designing the cement slurry with the required values of plastic viscosity, yield point or consistency coefficient contributes to the efficient performance of the cementing procedure and allows for effective filling of the cemented space outside the tubing. In order to adjust rheological parameters to technological requirements, dispersants are used. The operation of these plasticizers or superplasticizers is related to their chemical structure, which determines their liquefaction mechanism. Therefore, in order to properly select a fluidizing agent, it is beneficial to become familiar with its mechanism of operation, thanks to which it will be possible to use the optimal amounts for a given cement slurry recipe. The publication discusses the effectiveness of dispersing agents depending on their liquefaction mechanism. The research work carried out consisted in the modification of the cement slurry with the use of sodium salts of polycondensates of naphthalene sulfonic acids and a polymer dispersant based on carboxylates. Amounts of dispersant ranging from 0.05% (bwoc) to 1.0% (bwoc) were used. The rheological parameters described by means of five rheological models, i.e. Newton, Bingham, Ostwald de Waele, Casson and Herschele-Bulkley, were tested for the cement slurries. The main goal of the work presented in the article was to conduct a correlation analysis of the change in rheological parameters of slurries modified with dispersants belonging to different groups depending on their liquefaction mechanism. Thanks to this, it was possible to indicate the effectiveness of the dispersing additives depending on the amount of the fluid used belonging to a specific group. The work carried out is helpful in determining the optimal amount of dispersing agent depending on its type (mechanism of action).

scholarly journals Influence of Graphene Oxide on Rheological Parameters of Cement Slurries

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5441
Author(s):  
Marcin Kremieniewski
Keyword(s):  
Graphene Oxide ◽  
Plastic Viscosity ◽  
Rheological Parameters ◽  
Rheological Parameter ◽  
Cement Composites ◽  
Cement Slurry ◽  
Rheological Models ◽  
Industrial Sectors ◽  
Flow Limit ◽  
Parameter Values

In recent years, graphene-based nanomaterials have been increasingly and widely used in numerous industrial sectors. In the drilling industry, graphene oxide in cement slurry has significantly improved the mechanical parameters of cement composites and is a future-proof solution. However, prior to placing it in a borehole ring space, cement slurry must feature appropriate fluidity. Graphene oxide has a significant influence on rheological parameters. Therefore, it is necessary to study graphene oxide’s influence on the rheological parameters of cement slurries. Thus, this paper presents rheological models and the results of studies on rheological parameters. A basic cement slurry and a slurry with a latex addition were used. The latex admixture was applied at concentrations of 0.1%, 0.03%, and 0.06%. In total, studies were carried out for six slurries with graphene oxide and two basic slurries. The obtained results of studies on the slurries with graphene oxide were compared with the control slurry. It was found that the smallest graphene oxide concentration increased slurry value, some rheological parameter values, plastic viscosity, and the flow limit. Surprisingly, a concentration up to 0.03% was an acceptable value, since the increase in plastic viscosity was not excessively high, which allowed the use of cement slurry to seal the hole. Once this value was exceeded, the slurry caused problems at its injection to the borehole.

Modelling of Flow Properties of Asphalt Mastics

2013 ◽  
Vol 752 ◽  
pp. 209-216 ◽  
Author(s):  
Róbert Géber ◽  
László A. Gömze
Keyword(s):  
Research Work ◽  
Road Construction ◽  
Test Results ◽  
Flow Properties ◽  
Rheological Models ◽  
Fine Grained ◽  
Mineral Particles ◽  
Asphalt Mastics ◽  
Rheological Modelling ◽  
Mineral Fillers

The present research work deals with the examination and rheological modelling of flow properties of asphalt mastics which are the most important components of asphalt concretes. Asphalt mastics are mixtures of fine grained mineral filler particles (d<0,063 mm) and bitumen, having a stabilizing role in asphalt mixtures and largely determining the cohesion between mineral particles and bitumen. During our examinations two types of mineral fillers – limestone and dolomite – as well as standard bitumen were tested, which are extensively used in Hungarian road construction. Asphalt mastic mixtures were prepared out of these materials and they were tested with dynamic shear rheometer (DSR). According to the test results, rheological models of mastics were determined. It has been established that at different test temperatures and shear rate ranges asphalt mastics behave as Herschel-Bulkley and Bingham-type materials.

Zaczyny cementowe z dodatkiem nanorurek węglowych do uszczelniania otworów wiertniczych o wysokiej temperaturze i ciśnieniu złożowym (150°C, 90 MPa)

Nafta-Gaz ◽  
2021 ◽  
Vol 77 (5) ◽  
pp. 323-331
Author(s):  
Miłosz Kędzierski ◽  
◽  
Marcin Rzepka ◽  
Keyword(s):  
Carbon Nanotubes ◽  
Compressive Strength ◽  
High Temperature ◽  
Rheological Parameters ◽  
External Diameter ◽  
Mechanical Parameters ◽  
Cement Slurry ◽  
Significant Information ◽  
High Temperature And Pressure ◽  
Temperature And Pressure

The article presents the results of the influence of carbon nanotubes on the mechanical parameters of cement stones under high temperature and pressure conditions (150°C, 90 MPa). The tests used multi-walled carbon nanotubes (MWCNTs) with an external diameter of 10–20 nm and a length of 10–30 μm. Cement slurries contained 0.1% of CNTs bwoc (by the weight of cement). Laboratory tests of cement slurries were carried out at the Oil and Gas Institute – National Research Institute. The tests were carried out under conditions of increased pressure and temperature at 150°C, 90 MPa. Cement slurries were prepared on the basis of class G drilling cement. Developing recipes were guided by the requirements to be met by cement slurry for the cementing of casing in the conditions of high temperature and reservoir pressures. The densities of tested slurries ranged from 1900 kg/m3 to 2250 kg/m3 (slurries with the addition of hematite). The cement slurries were tested for density, fluidity, rheological parameters, filtration and thickening time. Compressive strength tests and measuring adhesion were carried out after 2, 7, 14 and 28 days. Cement slurry recipes with very good technological parameters were developed and after curing (after 28 days of hydration) had very high values of compressive strength, reaching up to 45 MPa. Cements were characterized by high values of adhesion to pipes reaching up 7 MPa after 28 days. The research showed significant information about possible applications of carbon nanotubes to modify the cement slurry under conditions of high temperature and pressure. The conducted tests confirmed that the addition of even small amounts of CNTs improves the mechanical parameters of the cement stone compared to the base sample without such addition, and also reduces the thickening time of cement slurries and reduces filtration. It is investigated that CNTs addition increases the viscosity and yield point of cement slurry. As a result, slurries with the addition of MWCNTs will more effectively displace the mud from the borehole and significantly affect the quality of cementation.

Enhancement lubricity properties of water-based mud with nanoparticles

2020 ◽  
pp. 70-74
Author(s):  
V.V. Guliyev ◽  
◽  
◽  
Keyword(s):  
Yield Point ◽  
Coefficient Of Friction ◽  
Drilling Fluid ◽  
Research Work ◽  
Shear Thinning ◽  
Rheological Parameters ◽  
Drilling Process ◽  
Drilling Mud ◽  
Pseudoplastic Fluid ◽  
Water Based

Currently, a great number of drilling fluids with different additives are used all over the world. Such additives are applied to control the properties of the drilling mud. The main purpose for controlling is to achieve more effective and safe drilling process. This research work aims to develop Water-Based Mud (WBM) with a Coefficient of Friction (CoF) as low as Oil-Based Mud (OBM) and better rheological properties. As it is known, produced CoF by WBM is higher than OBM, which means high friction between wellbore or casing and drill string. It was the reason for studying the effect of nanosilica on drilling fluid properties such as lubricity, rheological parameters and filtrate loss volume of drilling mud. The procedures were carried out following API RP 13B and API 13I standards. Five concentrations of nanosilica were selected to be tested. According to the results obtained, it was defined that adding nanosilica into the mud decreases CoF of basic WBM by 26 % and justifies nanosilica as a good lubricating agent for drilling fluid. The decreasing trend in coefficient of friction and plastic viscosity for nanosilica was obtained until the concentration of 0.1 %. This reduction is due to the shear thinning or pseudoplastic fluid behavior. After 0.1 %, an increase at PV value trend indicates that it does not follow shear thinning behavior and after reaching a certain amount of dissolved solids in the mud, it acts like normal drilling fluid. The yield point of the mud containing nanoparticles was higher than the basic one. Moreover, a growth in the concentration leads to an increase in yield point value. The improvement of this fluid system cleaning capacity via hydraulics modification and wellhole stability by filter cake endurance increase by adding nanosilica is shown as well. The average well construction data of “Neft Dashlary” field was used for the simulation studies conducted for the investigation of hydraulics parameters of reviewed fluids for all series of experiments. The test results were accepted reliable in case of at least 3 times repeatability.

The Chemical Structure Association Trust

2016 ◽  
Vol 38 (2) ◽  
Author(s):  
Bonnie Lawlor
Keyword(s):  
Chemical Structure ◽  
Scientific Discovery ◽  
Research Work ◽  
50Th Anniversary ◽  
The United States ◽  
Chemical Information ◽  
Structure Information ◽  
Chemical Structures ◽  
Grant Program ◽  
Structure Association

AbstractThe Chemical Structure Association Trust (CSA Trust) is an internationally-recognized, registered charity that promotes and supports the advancement of scientific discovery through the application of computer technologies in the management and analysis of chemical structure information. In support of its Charter, the Trust provides grants specifically to nurture young scientists, ages thirty-five or younger, who have demonstrated excellence in research related to the storage, retrieval, and analysis of chemical structures, reactions, and compounds. Since its inception in 1988, almost one hundred students and researchers worldwide have benefited from travel bursaries and the CSA Trust Grant Program to further their education and research work, but the organization has a rich history that predates the formalization of its charity status. Its roots were planted half a century ago in 1965, when the Chemical Notation Association (CNA) was formed in the United States. It has been an interesting journey from the CNA to the CSA Trust and I have been blessed to have been a part of it almost from the beginning, along with other members of the American Chemical Society’s Division of Chemical Information. In honor of the organization’s 50th Anniversary, I’d like to give a brief overview of its past and its present activities.

scholarly journals Ultra-Lightweight Cement Slurry to Seal Wellbore of Poor Wellbore Stability

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3124 ◽  
Author(s):  
Marcin Kremieniewski
Keyword(s):  
Control Sample ◽  
Wellbore Stability ◽  
Rheological Parameters ◽  
Light Weight ◽  
Technological Parameters ◽  
Cement Slurry ◽  
Sedimentation Stability ◽  
Cement Sheath ◽  
Sheath Structure ◽  
Poor Stability

The article presents the recipe for ultra-lightweight cement slurry for wellbore sealing. In ordinary lightweight cement slurries, the addition of microspheres and a large amount of water are used to maintain rheological parameters. This is a problem because the light particles of microspheres segregate. The cement sheath from such a cement slurry has an anisotropic microstructure and does not stabilize the casing column. In the new ultra-light cement slurry, 60% aluminosilicate microspheres and a large amount of water were used. The ultra-light weight slurry has a density below 1.2 g/cm3. This cement slurry does not segregates and in the sedimentation stability test has the same density at all measuring points. The cement slurry, despite the larger amount of water, has the same filtration as the control sample. The technological parameters of the slurry are adapted to the borehole conditions. Cement slurry is a ready-made application to seal a borehole with poor wellbore stability under conditions of 40 °C and 10 MPa pressure. The cement sheath structure in the wellbore after binding is homogeneous. The use of such slurry allows to reduce the risk of wall damage in wellbores of poor stability.

scholarly journals A novel ensemble based recommendation approach using network based analysis for identification of effective drugs for Tuberculosis

2021 ◽  
Vol 19 (1) ◽  
pp. 873-891
Author(s):  
Rishin Haldar ◽  
◽  
Swathi Jamjala Narayanan
Keyword(s):  
Chemical Structure ◽  
Research Work ◽  
Computational Techniques ◽  
Chemical Structures ◽  
Pharmacokinetic Properties ◽  
Resistant Strains ◽  
Drug Resistant Strains ◽  
Effective Drugs ◽  
Ranking Technique ◽  
Initial List

<abstract> <p>Tuberculosis (TB) is a fatal infectious disease which affected millions of people worldwide for many decades and now with mutating drug resistant strains, it poses bigger challenges in treatment of the patients. Computational techniques might play a crucial role in rapidly developing new or modified anti-tuberculosis drugs which can tackle these mutating strains of TB. This research work applied a computational approach to generate a unique recommendation list of possible TB drugs as an alternate to a popular drug, EMB, by first securing an initial list of drugs from a popular online database, PubChem, and thereafter applying an ensemble of ranking mechanisms. As a novelty, both the pharmacokinetic properties and some network based attributes of the chemical structure of the drugs are considered for generating separate recommendation lists. The work also provides customized modifications on a popular and traditional ensemble ranking technique to cater to the specific dataset and requirements. The final recommendation list provides established chemical structures along with their ranks, which could be used as alternatives to EMB. It is believed that the incorporation of both pharmacokinetic and network based properties in the ensemble ranking process added to the effectiveness and relevance of the final recommendation.</p> </abstract>

Degradation of safranin by heterogeneous Fenton processes using peanut shell ash based catalyst

2019 ◽  
Vol 79 (7) ◽  
pp. 1367-1375
Author(s):  
Amir Ikhlaq ◽  
Hafiza Zara Anwar ◽  
Farhan Javed ◽  
Saba Gull
Keyword(s):  
Research Work ◽  
Agitation Speed ◽  
Peanut Shell ◽  
H2o2 Concentration ◽  
Fenton Process ◽  
Heterogeneous Fenton ◽  
Initial Concentration ◽  
Industrial Sectors ◽  
Efficient Performance ◽  
Maximum Decolorization

Abstract Today, dyes are one of the major problematic pollutants in the environment and are broadly used in several industrial sectors. In the current research work, decolorization of safranin (basic dye) from aqueous solution was investigated using iron-impregnated peanut shell ash (Fe-PSA) as a catalyst in the UV-assisted heterogeneous Fenton process (Fe-PSA/H2O2/UV). The effect of parameters such as H2O2 concentration, catalyst dose, pH, initial dye concentration, temperature, and agitation speed was studied. The maximum decolorization of safranin was achieved at optimum parametric values of reagent dose = 8 mM, catalyst dose = 0.5 g, pH = 3, initial concentration of safranin = 50 ppm, temperature = 25 °C, and agitation speed = 200 rpm. The results revealed the efficient performance of Fe-PSA as catalyst in the Fe-PSA/H2O2/UV process for safranin treatment.

scholarly journals Grouting Reinforcement Technique in Wind Oxidation Zone by Power Law Superfine Cement Slurry Considering the Time-Varying Rheological Parameters

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Dengxing Zhu ◽  
Yu Guo ◽  
Wei Wang ◽  
Gangye Guo ◽  
Tieliang An
Keyword(s):  
Power Law ◽  
Coal Mine ◽  
Effective Diffusion ◽  
Oxidation Zone ◽  
Rheological Parameters ◽  
Time Varying ◽  
Cement Slurry ◽  
Permeability Characteristics ◽  
Grouting Pressure ◽  
Roof Strata

With the recovery of the wind oxidation zone in 13116 working face of Gubei Coal Mine as the engineering background, the occurrence condition of coal seam and the bedrock wind oxidation zone characteristics were analyzed. On this basis, the time-varying rheological parameters of superfine cement slurry and the permeability characteristic parameters of roof strata in wind oxidation zone were measured; then, a grout diffusion equation was established with the parameters obtained previously for the permeability characteristics of roof strata in the wind oxidation zone of Gubei Coal Mine. The grouting design was applied in actual engineering projects and its engineering effect has been proved to be satisfactory. The results indicate that superfine cement slurry whose water-cement ratio is 0.6 is a typical power-law slurry consistent with time-varying rheological parameters. It has better rheological properties during pumpable period, and its rheological parameters can be controlled by highly dispersive nano-SiO2 and polycarboxylate superplasticizer. For grouting in wind oxidized zone, comprehensive consideration must be given to effective permeability Ke, porosity  ∅ , and time-varying rheological parameters c0, k, and n. To realize effective diffusion of grouting in coal and rock mass, grouting pressure and diffusion time must be reasonably designed rather than excessively increased.

Effects of composition, temperature and shear rate on chocolate milk rheology: an empirical modeling approach incorporating yield behavior

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Asif A. Qaiser ◽  
Rabia Nazar ◽  
Mehroz Anjum ◽  
Anem Saeed ◽  
Muhmmad Zeeshan ◽  
...  
Keyword(s):  
Xanthan Gum ◽  
Model Fitting ◽  
Empirical Modeling ◽  
Rheological Parameters ◽  
Model Parameters ◽  
Chocolate Milk ◽  
Rheological Models ◽  
Shear Rates ◽  
Milk Processing ◽  
Semi Empirical

Abstract This study elucidates the effects of composition and temperature on the rheological behavior of chocolate milk formulation. The fat [0.5, 1 and 1.5 g] and xanthan gum contents [0.05, 0.1 and 0.15 g] varied and shear stress-strain rate data were recorded at varying temperature [21.4, 65 and 80 °C]. All compositions showed predominantly a pseudoplastic behavior [i.e., pseudoplasticity index, n < 1] with a strong influence on composition and temperature. Three semi-empirical rheological models, i.e. Power-law, Herschel–Bulkely, and Casson models were fitted on the data using an in-house developed computer program for the best statistical fit. The pseudoplasticity index [n] varied with the composition that initially decreased with temperature and subsequently increased. The other model parameters such as consistency index [k], Casson and Herschel–Bulkely yield stress, and Casson viscosity [at a specified rate i.e., 34.7 s−1] were computed through model fitting and correlated to the microstructural changes inside the fluid keeping in view the composition and temperature. This study helps in correlating chocolate milk processing and quality control based on complex microstructure to the rheological parameters measured at simulated temperatures and shear rates.

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