scholarly journals Method for determining the starting moment of hydrate formation on the basis of optical effects

2021 ◽  
Vol 230 ◽  
pp. 01003
Author(s):  
Nazar Pedchenko ◽  
Yuriy Vynnykov ◽  
Larysa Pedchenko ◽  
Mykhailo Pedchenko
Keyword(s):  
Gas Hydrates ◽  
Oil And Gas ◽  
Experimental Studies ◽  
Hydrate Formation ◽  
Light Sources ◽  
Interphase Surface ◽  
Laboratory Observation ◽  
Industrial Facilities ◽  
Optical Effects ◽  
Reservoir Systems

The problem is analyzed of hydrate formation in the systems of gathering and treating of oil and gas products. The methods are studied for prevention of complications associated with the gas hydrates accumulation in the pipelines and process lines. Attention is focused on the significant material costs to prevent the hydrate formation and ways to reduce them. The necessity of constant laboratory monitoring for reservoir systems at industrial facilities to determine the hydrate formation parameters has been substantiated. The need to improve the method for determining the hydrate formation parameters for complex reservoir systems based on a mixture of hydrate-forming gases has also been proved. The purpose of the work is to improve the research method of reservoir systems immediately at the facilities of products mining and treatment. The peculiarities are analyzed of the method of visual laboratory observation in the study of gas hydrates. During experimental studies, optical effects of image distortion are observed due to the formation of a gas hydrate layer in the form of a film on the interphase surface. The mechanism of their formation, as well as the processes determining them have been substantiated. Based on this effect, a method of fixing the hydrate formation initial stage (beginning of crystal growth – mass crystallization) is proposed. For increasing the informative ability of the obtained images of hydrate formation processes, it is proposed to “paint” them with the help of colored light sources, as well as to regulate the intensity and direction of illumination. A number of photos are presented, which clearly illustrate the processes described in the paper.

Self-preservation Effect of Gas Hydrates

2021 ◽  
Vol 23 ◽  
pp. 346-355
Author(s):  
Anatoliy Pavlenko
Keyword(s):  
Gas Hydrates ◽  
Gas Hydrate ◽  
Experimental Studies ◽  
Interphase Surface ◽  
Quantitative Characteristics ◽  
Nonequilibrium Conditions ◽  
Water Simulation ◽  
Gas Loss ◽  
Physical And Mathematical Models ◽  
And Storage

This work was performed to improve the storage and transportation technology of gas hydrates in nonequilibrium conditions. At atmospheric pressure and positive ambient temperature, they gradually dissociate into gas and water. Simulation of the gas hydrate dissociation will determine optimal conditions for their transportation and storage, as well as minimize gas loss. Thermodynamic parameters of adiabatic processes of forced preservation of pre-cooled gas hydrate blocks with ice layer were determined theoretically and experimentally. Physical and mathematical models of these processes were proposed. The scientific novelty is in establishing quantitative characteristics that describe the gas hydrates thermophysical parameters thermophysical characteristics influence on the heat transfer processes intensity on the interphase surface under conditions of gas hydrates dissociation. Based on the results of experimental studies, approximation dependences for determining the temperature in the depths of a dissociating gas hydrate array have been obtained. Gas hydrates dissociation mathematical model is presented.

scholarly journals Simulation of Hydrate Phase Boundary for Natural Gas Mixture with High CO2Content through Simulation

2019 ◽  
Vol 9 (2) ◽  
pp. 4030-4034
Keyword(s):  
Natural Gas ◽  
Gas Hydrates ◽  
Oil And Gas ◽  
Hydrate Formation ◽  
Gas Production ◽  
Gas Mixture ◽  
Oil And Gas Production ◽  
Equation Of States ◽  
Gas Molecules ◽  
Simulation Results

Gas hydrates are solid crystalline structures in which water molecules trap small guest gas molecules and encage them through hydrogen bonding. Gas hydrates are known to be problematic in flow assurance applications as they can form plug inside the pipelines during oil and gas production, transportation and processing. In order to inhibit hydrate formation thermodynamically, various chemicals including some alcohols e.g. methanol (MeOH), mono- ethylene glycol (MEG) are used as thermodynamic hydrate inhibitors (THIs). In this paper, a simulation study is performed using PVTsim software wherein it predicts the hydrate formation for pure CO2 solution mixture and CO2 -MEG solution mixture systems using different equation of states. These equations of states include Soave-Redlich-Kwong (SRK), SRK-Peneloux, Peng- Robinson (PR) and Peng-Robinson Peneloux. The simulation results obtained using these equation of states were validated with the experimental data and PRPenelouxEoS was found to be in better agreement. The hydrate formation regions are determined in between the pressure range of 10 to 110 bara for natural gas mixture containing high percentage of CO2 in it. The inhibitors are used in 5, 10 and 20 wt% concentrations. The hydrate inhibition efficiency increased with the increase in concentration. Simulation results showed that methanol performed better in comparison to the other inhibitors at all concentrations.

Modeling of Gas Hydrate Formation in a High Pressure Reactor

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Ajay Mandal ◽  
Sukumar Laik
Keyword(s):  
Kinetic Model ◽  
Gas Hydrates ◽  
Gas Hydrate ◽  
Oil And Gas ◽  
Hydrate Formation ◽  
System A ◽  
Gas Hydrate Formation ◽  
Simple Kinetic Model ◽  
Geometric Variables ◽  
Order Rate Equation

Gas hydrates are now gaining importance in oil and gas industries because they are considered a future source of energy and a means for the transport of natural gas. On the other hand gas hydrates create problems by plugging the pipelines during transportation. Obviously, predicting the conditions in which hydrates are formed would be valuable. In the present study, experiments were performed to observe the conditions, which favor the formation of an ethane gas hydrate. The results of the hydrate formation are elucidated with the help of a conceptual kinetic model. An empirical correlation is developed to predict the rate of formation of the hydrate in terms of the operating and geometric variables of the system. A simple kinetic model based on the dissolved ethane gas is also developed which shows that the hydrate formation follows the first order rate equation.

Surfactant Effect of Promoting Research on Hydrate Formation

2015 ◽  
Vol 1092-1093 ◽  
pp. 220-225
Author(s):  
Lei Wang ◽  
Shu Li Wang ◽  
Tian Tian Kang
Keyword(s):  
Gas Hydrates ◽  
Induction Time ◽  
Oil And Gas ◽  
Formation Rate ◽  
Technical Problem ◽  
Hydrate Formation ◽  
Oil And Gas Industry ◽  
Research Direction ◽  
Equal Concentration ◽  
Observation Method

Gas hydrates are a major concern in oil and gas industry, Gas hydrates form in small amounts of water, gas, and the appropriate pressure and temperature conditions. Gas hydrate storage and transportation technology starts a new way for energy storage and transportation industry. The most critically technical problem is how to improve the hydrate formation rate, storage capacity and form continuously. The influences of surfactants on induction time in three types of solution with equal concentration were studied by means of visual hydrate experimental equipment, and generalized induction time was measured by direct observation method. Specific effects of different surfactants on hydrate formation were summarized, as well as the hydrate formation mechanism of surfactants . The lack of research and the research direction of the future were concluded . The further study of surfactant mechanism and build kinetics model containing surfactant have important theoretical value . The result shows that the gas molecules saturated due to the solubilization of surfactant, which promotes the progress of mass transfer in the hydrates. And driving force is provided for the complexation of host molecules and guest molecules during the formation progress of gas hydrates.

scholarly journals Thermodynamic Modeling Of Electrolytic Solutions of Ionic Liquids for Gas Hydrates Inhibition Applications

2021 ◽  
Vol 81 (2) ◽  
pp. 110-123
Author(s):  
Ali Qasim ◽  
Jeremy Heurtas ◽  
Muhammad Saad Khan ◽  
Bhajan Lal ◽  
Azmi Mohammad Shariff ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Gas Hydrates ◽  
Oil And Gas ◽  
Binary Solution ◽  
Hydrate Formation ◽  
Absolute Error ◽  
Economic Loss ◽  
Average Absolute Error ◽  
Mixed Gas ◽  
Gas Hydrate Formation

The formation of hydrates in oil and gas transmission pipelines can cause blockage inside them and disrupt the normal flow. It may cause safety problems along with economic loss. To avoid these problems, it is necessary to have knowledge about gas hydrate formation. In this regard, hydrate liquid vapor equilibrium (HLVE) modeling can prove to be of significance as it predicts the phenomenon accurately. Dickens and Quinby-Hunt model is used to predict HLVE points. The experimental data has been obtained from open literature concerning inhibition of gas hydrates. The electrolytic binary solution mixtures of ionic liquids and quaternary ammonium salts (QAS) with commercial hydrate inhibitors have been taken into consideration. Methanol and mono ethylene glycol (MEG) are commercially used inhibitors. The gases forming hydrates include CO2, CH4 and mixed gas (CO2/CH4/N2). The experimental results are compared with the results obtained through modeling. The results show the applicability of the model as in case of QAS+MEG solution mixture hydrates with CO2, it shows a good fit. The HLVE findings by model for CH4 hydrates with EMIM-Cl+MEG solution mixture showed an average absolute error of less than 1% which is acceptable. The binary solution mixtures of NaCl+MEG, NaCl+MeOH and CaCl2+MeOH with tertiary gas mixture rich in CO2 were also modeled to find and compare the HLVE points from literature. It is found that the selected model is more suitable to be used in low pressure conditions and at high pressure, average absolute error (AAE) between experimental and modeling values is also high. It shows the suitability of the model and it can be further used in case of ionic compounds to predict hydrate inhibition behavior.

scholarly journals Surface Coatings and Treatments for Controlled Hydrate Formation: A Mini Review

Physchem ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 272-287
Author(s):  
Tausif Altamash ◽  
José M. S. S. Esperança ◽  
Mohammad Tariq
Keyword(s):  
High Pressure ◽  
Gas Hydrates ◽  
Atmospheric Pressure ◽  
Oil And Gas ◽  
Hydrate Formation ◽  
Oil And Gas Industry ◽  
Surface Coatings ◽  
Chemical Methods ◽  
Gas Industry ◽  
Made In

Gas hydrates (GHs) are known to pose serious flow assurance challenges for the oil and gas industry. Neverthless, over the last few decades, gas hydrates-based technology has been explored for various energy- and environmentally related applications. For both applications, a controlled formation of GHs is desired. Management of hydrate formation by allowing them to form within the pipelines in a controlled form over their complete mitigation is preferred. Moreover, environmental, benign, non-chemical methods to accelerate the rate of hydrate formation are in demand. This review focused on the progress made in the last decade on the use of various surface coatings and treatments to control the hydrate formation at atmospheric pressure and in realistic conditions of high pressure. It can be inferred that both surface chemistry (hydrophobicity/hydrophilicity) and surface morphology play a significant role in deciding the hydrate adhesion on a given surface.

Investigation of Drilling Problems in Gas Hydrate Formations

2008 ◽  
Author(s):  
Catalin Teodoriu ◽  
Gioia Falcone ◽  
Amodu Afolabi
Keyword(s):  
Gas Hydrates ◽  
Gas Hydrate ◽  
Oil And Gas ◽  
Drilling Fluid ◽  
Hydrate Formation ◽  
Oil And Gas Industry ◽  
Lessons Learned ◽  
Drilling Fluids ◽  
Drilling Mud ◽  
Gas Hydrate Formation

Gas hydrates are ice-like crystalline systems made of water and methane that are stable under high pressure and low temperature conditions. Gas hydrates have been identified as strategic resources and may surpass all known oil and gas reserves combined. However, these resources will become reserves only if the gas contained therein can be produced economically. In the oil and gas industry, gas hydrates may be encountered while drilling sediments of the subsea continental slopes and in the subsurface of permafrost regions. They also represent a flow assurance issue, as they may form in the well and in the flowlines, causing blockages. Deepwater drilling programmes have experienced problems when encountering gas hydrate formations. A major issue is that of phase transition, where gas hydrate goes from a solid state to dissociated gas and water, as there are rapid changes in fluid volumes and pressure. This can cause drilling equipment failure, borehole instability and formation collapse. After dissociation of water and gas, hydrates may be prevented from forming in the well by using appropriate inhibitors in the drilling mud. There is a need to develop fluids specifically for drilling through gas hydrate formations, either to unlock the unconventional reserves trapped in the crystalline gas hydrate structures or to safely reach underlying conventional reserves. To drill wells in a gas hydrate formation, a conductor casing is needed to allow close loop circulation of the mud, if different from seawater. The search for the ideal mud for drilling through gas hydrate formations must start with a review of past experiences worldwide and of the lessons learned. This paper presents a review of the problems encountered while drilling through gas hydrate formations. It identifies the key requirements for drilling fluids, based on the interaction between the drill bit, the drilling fluid and the formation. An evaluation of the environmental risk associated with drilling through gas hydrate formations is also presented.

The formation of gas hydrates under shock wave impact on the bubble media (two-dimensional case)

2010 ◽  
Vol 7 ◽  
pp. 90-97
Author(s):  
M.N. Galimzianov ◽  
I.A. Chiglintsev ◽  
U.O. Agisheva ◽  
V.A. Buzina
Keyword(s):  
Shock Wave ◽  
Gas Hydrates ◽  
Hydrate Formation ◽  
Dimensional Case ◽  
Two Dimensional ◽  
Wave Impact ◽  
Bubble Liquid ◽  
One Dimensional ◽  
Bubble Media ◽  
Main Factors

Formation of gas hydrates under shock wave impact on bubble media (two-dimensional case) The dynamics of plane one-dimensional shock waves applied to the available experimental data for the water–freon media is studied on the base of the theoretical model of the bubble liquid improved with taking into account possible hydrate formation. The scheme of accounting of the bubble crushing in a shock wave that is one of the main factors in the hydrate formation intensification with increasing shock wave amplitude is proposed.

Mathematical model of multiphase flow propagation for the case of underwater pipeline damage

2019 ◽  
Vol 14 (2) ◽  
pp. 142-147
Author(s):  
S.R. Kildibaeva ◽  
E.T. Dalinskij ◽  
G.R. Kildibaeva
Keyword(s):  
Oil And Gas ◽  
Control Volume ◽  
Hydrate Formation ◽  
Initial Moment ◽  
Hydrate Shell ◽  
Surrounding Water ◽  
Vertical Coordinate ◽  
Associated Gas ◽  
First Case ◽  
Underwater Pipeline

The paper deals with the case of damage to the underwater pipeline through which oil and associated gas are transported. The process of oil and gas migration is described by the flow of a multiphase submerged jet. At the initial moment, the temperature of the incoming hydrocarbons, their initial velocity, the temperature of the surrounding water, the depth of the pipeline is known. The paper considers two cases of different initial parameters of hydrocarbon outflow from the pipeline. In the first case, the thermobaric environmental conditions correspond to the conditions of hydrate formation and stable existence. Such a case corresponds to the conditions of the hydrocarbons flow in the Gulf of Mexico. In the second case, hydrate is not formed. Such flows correspond to the cases of oil transportation through pipelines in the Baltic sea (for example, Nord stream–2). The process of hydrate formation will be characterized by the following dynamics of the bubble: first, it will be completely gas, then a hydrate shell (composite bubble) will begin to form on its surface, then the bubble will become completely hydrate, which will be the final stage. The integral Lagrangian control volume method will be considered for modeling the dynamics of hydrocarbon jet propagation. According to this method, the jet is considered as a sequence of elementary volumes. When modeling the jet flow, the laws of conservation of mass, momentum and energy for the components included in the control volume are taken into account. The equations are used taking into account the possible formation of hydrate. Thermophysical characteristics of hydrocarbons coming from the damaged pipeline for cases of deep-water and shallow-water pipeline laying are obtained. The trajectories of hydrocarbon migration, the dependence of the jet temperature and density on the vertical coordinate are analyzed.

Thermodynamic Modelling of Gas Hydrate Formation in the Presence of Inhibitors and the Consideration of their Effect

2014 ◽  
Vol 14 (1) ◽  
pp. 45
Author(s):  
Peyman Sabzi ◽  
Saheb Noroozi
Keyword(s):  
Gas Hydrates ◽  
Gas Hydrate ◽  
Low Temperatures ◽  
Hydrate Formation ◽  
Transportation Systems ◽  
Flow Lines ◽  
Main Approach ◽  
Efficient Inhibitor ◽  
System A ◽  
Gas Hydrate Formation

Gas hydrates formation is considered as one the greatest obstacles in gas transportation systems. Problems related to gas hydrate formation is more severe when dealing with transportation at low temperatures of deep water. In order to avoid formation of Gas hydrates, different inhibitors are used. Methanol is one of the most common and economically efficient inhibitor. Adding methanol to the flow lines, changes the thermodynamic equilibrium situation of the system. In order to predict these changes in thermodynamic behavior of the system, a series of modelings are performed using Matlab software in this paper. The main approach in this modeling is on the basis of Van der Waals and Plateau's thermodynamic approach. The obtained results of a system containing water, Methane and Methanol showed that hydrate formation pressure increases due to the increase of inhibitor amount in constant temperature and this increase is more in higher temperatures. Furthermore, these results were in harmony with the available empirical data.Keywords: Gas hydrates, thermodynamic inhibitor, modelling, pipeline blockage

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