This document summarizes a study on the kinetics of sII and sH gas hydrate formation from a surface phenomenon point of view. The study used experimental methods including atmospheric and high pressure hydrate formation in stirred reactors and interfacial tension measurements. Results showed that certain surfactants like Triton X-100 and NPE6EO significantly increased the hydrate formation rate by lowering the interfacial tension between gas hydrate formers and water. Specifically, these surfactants promoted the formation of methane sH hydrate at rates over 400% higher than without surfactants. The induction time for sH hydrate formation was also found to be independent of initial pressure.
Armfield Gas Absorption Column ExperimentHadeer Khalid
The absorption of CO2 from air to water was studied in Gas absorption column built by Armfield company. Lab report and experiment was part of Separation Lab.
Modelling and Simulation of Shell and Tube Heat Exchanger Using different Typ...IJMREMJournal
The shell and tube type of heat exchanger module is to be used for simulation study of various fluid systems on
rate of heat transfer. The ionic fluids are used to see the difference in outlet temperature of fluid as compared to
reference fluid. The cooling fluid is made by adding various amounts of solutes to water and the effect is observed
on rate. Also suggestions are made on the nature of heat transfer, rate of heat transfer and improved effectiveness
in the rate of heat transfer as compared to the normal process. The conclusions are made about the best simulated
results obtain from Chemcad software on rate of heat transfer.
Modelling and Simulation of Shell and Tube Heat Exchanger Using different Typ...IJMREMJournal
The shell and tube type of heat exchanger module is to be used for simulation study of various fluid systems on rate of heat transfer. The ionic fluids are used to see the difference in outlet temperature of fluid as compared to reference fluid. The cooling fluid is made by adding various amounts of solutes to water and the effect is observed on rate. Also suggestions are made on the nature of heat transfer, rate of heat transfer and improved effectiveness in the rate of heat transfer as compared to the normal process. The conclusions are made about the best simulated results obtain from Chemcad software on rate of heat transfer.
The document describes the process for selecting the German team for the International Chemistry Olympiad (IChO), which involves 4 rounds of testing. Students first complete problems at home, then the top scorers advance to chemistry camps involving theoretical and practical exams. The top 15 students then participate in a final week-long practical training camp, after which the IChO team is selected. The document also provides the problems and solutions for each round of the national competition.
The document summarizes research on the effect of cathode stoichiometric ratio on the performance of proton exchange membrane fuel cells (PEMFCs) under cold operating conditions. It describes the background on PEMFCs and motivation for studying cold start performance. The project investigated how output voltage of a PEMFC is affected by changing the cathode stoichiometric ratio at room temperature, 0°C, and -3°C. Results showed that increasing the ratio improved performance at room temperature and 0°C but had little effect at -3°C, likely due to ice formation blocking gas flow. Recommendations to address sources of error in the experiment are also provided.
This lab report summarizes an experiment conducted to calculate the overall heat transfer coefficient (U) of a shell and tube heat exchanger with uniflow configuration. Temperature and flow rate data was collected for the hot and cold water streams at various flow rates. The heat transfer rate (Q) was calculated using this data and equations for mass flow rate and log mean temperature difference. The overall heat transfer coefficient (U) was then calculated for each set of data using the equation U=Q/(A*ΔTlm). U values ranged from 1.696 to 92.05 W/m2K over the range of flow rates tested in the uniflow shell and tube heat exchanger.
This document is a report on natural gas dehydration processes submitted by students at Koya University. It discusses the importance of removing water from natural gas and describes various dehydration methods. The most common methods are absorption using glycol and adsorption using desiccants. Absorption using triethylene glycol is identified as the most economical and effective process, as it requires less energy and maintenance than adsorption while achieving the necessary low water levels. The report provides details on how each dehydration method works and the advantages and limitations of absorption and adsorption processes.
Armfield Gas Absorption Column ExperimentHadeer Khalid
The absorption of CO2 from air to water was studied in Gas absorption column built by Armfield company. Lab report and experiment was part of Separation Lab.
Modelling and Simulation of Shell and Tube Heat Exchanger Using different Typ...IJMREMJournal
The shell and tube type of heat exchanger module is to be used for simulation study of various fluid systems on
rate of heat transfer. The ionic fluids are used to see the difference in outlet temperature of fluid as compared to
reference fluid. The cooling fluid is made by adding various amounts of solutes to water and the effect is observed
on rate. Also suggestions are made on the nature of heat transfer, rate of heat transfer and improved effectiveness
in the rate of heat transfer as compared to the normal process. The conclusions are made about the best simulated
results obtain from Chemcad software on rate of heat transfer.
Modelling and Simulation of Shell and Tube Heat Exchanger Using different Typ...IJMREMJournal
The shell and tube type of heat exchanger module is to be used for simulation study of various fluid systems on rate of heat transfer. The ionic fluids are used to see the difference in outlet temperature of fluid as compared to reference fluid. The cooling fluid is made by adding various amounts of solutes to water and the effect is observed on rate. Also suggestions are made on the nature of heat transfer, rate of heat transfer and improved effectiveness in the rate of heat transfer as compared to the normal process. The conclusions are made about the best simulated results obtain from Chemcad software on rate of heat transfer.
The document describes the process for selecting the German team for the International Chemistry Olympiad (IChO), which involves 4 rounds of testing. Students first complete problems at home, then the top scorers advance to chemistry camps involving theoretical and practical exams. The top 15 students then participate in a final week-long practical training camp, after which the IChO team is selected. The document also provides the problems and solutions for each round of the national competition.
The document summarizes research on the effect of cathode stoichiometric ratio on the performance of proton exchange membrane fuel cells (PEMFCs) under cold operating conditions. It describes the background on PEMFCs and motivation for studying cold start performance. The project investigated how output voltage of a PEMFC is affected by changing the cathode stoichiometric ratio at room temperature, 0°C, and -3°C. Results showed that increasing the ratio improved performance at room temperature and 0°C but had little effect at -3°C, likely due to ice formation blocking gas flow. Recommendations to address sources of error in the experiment are also provided.
This lab report summarizes an experiment conducted to calculate the overall heat transfer coefficient (U) of a shell and tube heat exchanger with uniflow configuration. Temperature and flow rate data was collected for the hot and cold water streams at various flow rates. The heat transfer rate (Q) was calculated using this data and equations for mass flow rate and log mean temperature difference. The overall heat transfer coefficient (U) was then calculated for each set of data using the equation U=Q/(A*ΔTlm). U values ranged from 1.696 to 92.05 W/m2K over the range of flow rates tested in the uniflow shell and tube heat exchanger.
This document is a report on natural gas dehydration processes submitted by students at Koya University. It discusses the importance of removing water from natural gas and describes various dehydration methods. The most common methods are absorption using glycol and adsorption using desiccants. Absorption using triethylene glycol is identified as the most economical and effective process, as it requires less energy and maintenance than adsorption while achieving the necessary low water levels. The report provides details on how each dehydration method works and the advantages and limitations of absorption and adsorption processes.
This document discusses potential improvements in methanol synthesis. It summarizes recent research on clarifying the chemistry of methanol synthesis, studying mass transfer limitations, and investigating catalyst deactivation and regeneration. Regarding the chemistry, experiments showed methanol synthesis proceeds primarily via CO2 hydrogenation. Mass transfer experiments in a slurry reactor characterized the effects of temperature, pressure, impeller speed and other variables on the overall gas-liquid mass transfer coefficient. Further improvements may come from developing catalyst regeneration processes and understanding all factors affecting catalyst life.
EFFECT OF CONCENTRATION OF LITHIUM BROMIDE MIXTURE ON COP FOR SINGLE EFFECT L...Editor IJMTER
In this paper effect of concentration of lithium bromide mixture on Co-efficient of
performance (COP) for single effect LiBr-H2O absorption chillers is calculated. Then find out how
the cop varies with the concentration of lithium bromide. For finding cop temperature of condenser
varies and the other parameter (temperature of generator, temperature of absorber, capacity of
evaporator, temperature of evaporator temperature of absorber) remains constant. Optimal value of
COP obtained 0.65 varying temperature of condenser.
This document reviews recent advances in using gas hydrates to capture carbon dioxide (CO2). It discusses how chemical additives and mechanical methods have been investigated to improve the efficiency of hydrate-based CO2 capture (HBCC) technology. Chemical additives like tetrahydrofuran and surfactants can act as promoters, reducing the pressure and time needed to form CO2 hydrates and increasing CO2 uptake. Mechanical methods aim to enhance gas-water contact and mass transfer. The review evaluates how these approaches impact important parameters like gas consumption, hydrate formation rates, and CO2 recovery and separation from gas mixtures. It also considers the limitations and challenges of HBCC compared to conventional CO2 capture technologies.
The document discusses proposed improvements to the circulating water treatment system at NLC TPS II power plant. It analyzes water parameters from the current system and identifies high hardness, alkalinity, dissolved solids and oxygen that promote corrosion and scaling. A new treatment system is proposed using increased chlorine dosing to control microbes, along with corrosion and scale inhibitors. Annual chemical consumption and costs are estimated for different cycles of concentration to reduce specific water consumption below 3.5 m3/MWh. Improving the treatment process aims to control corrosion, scaling and fouling in the circulating water system.
This document summarizes research on using electrodialysis and reverse osmosis to recover dissolved organic carbon from seawater. The researchers developed a process to concentrate seawater using reverse osmosis, followed by electrodialysis to remove salt, producing a desalinated sample for analysis. Over 15 experiments were conducted using seawater and brackish water samples, recovering 60-90% of dissolved organic carbon. Preliminary results found differences in the recovered high molecular weight fraction compared to previous methods. The combined process allows treatment of large volumes of seawater samples for scientific study of marine dissolved organic carbon.
The document discusses the use of variant question papers for some of CIE's most popular assessments. It explains that CIE uses two closely related variants of some question papers to provide more past examination material to students. For each variant, there is a corresponding mark scheme and examiner's report. The document contains both variants of the materials so that all centers have access to them. It provides guidance on how to identify which variant a particular paper belongs to based on labels at the top of the page. Anyone with additional questions should contact CIE's customer service team.
The document discusses CIE's use of variant question papers for some popular assessments with large candidatures. It explains that while the content and question types remain the same, there are now two variants of the question paper, mark scheme, and principal examiner's report for one component. Centres will use only one variant, but this provides access to more past examination material. It includes a diagram showing the relationship between the question papers, mark schemes, and reports for the two variants. The document also provides contact information for questions about these changes.
The document discusses the use of variant question papers for some of CIE's most popular assessments. It explains that CIE uses two closely related variants of some question papers to provide more past examination material to students. For each variant, there is a corresponding mark scheme and examiner's report. The document contains both variants of the materials so that all centers have access to them. It provides information on how to identify which variant a particular paper belongs to based on labels at the top of the page. Anyone with additional questions should contact CIE customer services.
This document provides information about an advanced chemical engineering thermodynamics course, including:
1) The course covers basic definitions, concepts, relationships for pure components and mixtures including pvT relationships and thermodynamic property relationships.
2) Relevant textbooks are listed for reference.
3) Methods for determining pvT properties of pure components and mixtures are discussed, including experimental determination, databases, equations of state, and process simulators.
4) The Lydersen and Pitzer methods for corresponding states are summarized, which use critical compressibility factor and acentric factor respectively as third parameters to determine compressibility factor from reduced temperature and pressure.
The document describes experimental studies of two cylindrical latent heat energy storage systems (LHESS) using lauric acid as the phase change material (PCM). The first is a horizontal cylinder with one finned copper pipe passing through the center. The second is a vertical cylinder with two finned copper pipes allowing for simultaneous charging and discharging. Experiments were conducted to study the phase change behavior of the PCM and heat transfer processes during charging, discharging, and simultaneous charging/discharging. Results show natural convection plays an important role in melting and simultaneous charging/discharging but less so in solidification.
Gas hydrate
To prepare natural gas for sale, its undesirable components (water, H2S and CO2) must be removed. Most natural gas contains substantial amounts of water vapor due to the presence of connate water in the reservoir rock. At reservoir pressure and temperature, gas is saturated with water vapor
Preliminary Study on biogas production from POME by DBD plasmaTELKOMNIKA JOURNAL
A new technology to produce biogas using a dielectric barrier discharge (DBD) plasma system
from palm oil mill effluent (POME) was investigated. The batch experiments were examined at applied
voltages of 15, 20 and 25 kV. The results showed that the highest yields of hydrogen and methane were
achieved at an applied voltage of 25 kV after 1 hour were 2.42 and 1.32 mL/mL of POME, respectively.
The biogas was composed of 65% hydrogen and 35% methane. In order to make the results of this study
applicable to biogas plants, the effects of flowrate and consumed energy are important parameters that
should be further investigated in a future study.
Gas HydratesGas HydratesGas HydratesGas HydratesGas Hydratesminaapascal
This document discusses gas hydrates as an energy resource. It begins with an overview of the global energy situation and increasing demand. Gas hydrates are then defined as naturally occurring structures where gas molecules are trapped within ice crystals under certain pressure and temperature conditions. The document outlines the significant worldwide reserves of gas hydrates, particularly in ocean sediments, and different exploitation methods including depressurization, inhibitor injection, and thermal stimulation. Mathematical models for fluid flow, heat transfer, and species transport during gas hydrate dissociation are also presented. The document concludes that gas hydrates represent an important potential energy source and that further research is needed to safely exploit methane from hydrate reservoirs.
This document summarizes a study on the kinetics of methanol synthesis from carbon dioxide hydrogenation over copper-zinc oxide catalysts. Experiments were conducted in a fixed bed reactor between 200-230°C, 50-80 bar, and gas hourly space velocities of 7,800-23,400 h-1 using feeds with H2:CO2 ratios of 2-6 without CO. Kinetic parameters from a previous study were optimized to model the experimental data using a Langmuir–Hinshelwood–Hougen–Watson mechanism. The influences of catalyst support (alumina vs zirconia) and operating conditions on kinetics were examined. The goal was to determine optimized parameters to reliably scale-up the
The document presents a study on the hydrodynamic behavior of an external loop airlift reactor for two-phase systems. Experiments were conducted to determine the gas holdup and pressure drop characteristics of various electrolyte and solvent solutions at different concentrations and flow rates. The results show that gas holdup increases with superficial gas velocity and solvent concentration but decreases with electrolyte concentration, while pressure drop increases with gas velocity, liquid flow rate, and solution concentration.
The document summarizes an experiment studying factors that affect CO2 absorption in a NaOH solution. The experiment tested how absorption is affected by flow rate of CO2 gas, CO2 concentration, volume of NaOH solution, and pH. Absorption increased with lower flow rates, higher NaOH volumes, and higher pH. The results supported theories that more CO2 absorbs at higher pressures and NaOH concentrations. Future studies could optimize flow rates to maximize both absorption capacity and breakthrough time.
This document discusses various processes for separating and enriching the tritium isotope. It begins by introducing tritium isotope separation and some key concepts. It then describes several processes that have been used to enrich tritium for analytical purposes, including water electrolysis, water distillation, thermal diffusion, and permeation through membranes. The document also discusses processes that have been used to recover and enrich tritium from nuclear power plants, such as water distillation, thermal diffusion, adsorption, and chromatography. It emphasizes that effective tritium separation and control is important for both the nuclear power and potential fusion power industries.
This document summarizes a study on the thermal performance of a shell and tube heat exchanger using nanofluids. Finite volume modeling was used to analyze heat transfer and flow characteristics. Various nanofluids including Ag, Al2O3, CuO, SiO2, and TiO2 suspensions in water were tested and compared to pure water. The objectives were to analyze temperature profiles, heat transfer coefficients, pressure drops, and effectiveness. Results showed nanofluids had higher overall temperatures indicating more heat transfer compared to water alone. This study analyzed the potential for nanofluids to enhance heat exchanger performance.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
This document discusses potential improvements in methanol synthesis. It summarizes recent research on clarifying the chemistry of methanol synthesis, studying mass transfer limitations, and investigating catalyst deactivation and regeneration. Regarding the chemistry, experiments showed methanol synthesis proceeds primarily via CO2 hydrogenation. Mass transfer experiments in a slurry reactor characterized the effects of temperature, pressure, impeller speed and other variables on the overall gas-liquid mass transfer coefficient. Further improvements may come from developing catalyst regeneration processes and understanding all factors affecting catalyst life.
EFFECT OF CONCENTRATION OF LITHIUM BROMIDE MIXTURE ON COP FOR SINGLE EFFECT L...Editor IJMTER
In this paper effect of concentration of lithium bromide mixture on Co-efficient of
performance (COP) for single effect LiBr-H2O absorption chillers is calculated. Then find out how
the cop varies with the concentration of lithium bromide. For finding cop temperature of condenser
varies and the other parameter (temperature of generator, temperature of absorber, capacity of
evaporator, temperature of evaporator temperature of absorber) remains constant. Optimal value of
COP obtained 0.65 varying temperature of condenser.
This document reviews recent advances in using gas hydrates to capture carbon dioxide (CO2). It discusses how chemical additives and mechanical methods have been investigated to improve the efficiency of hydrate-based CO2 capture (HBCC) technology. Chemical additives like tetrahydrofuran and surfactants can act as promoters, reducing the pressure and time needed to form CO2 hydrates and increasing CO2 uptake. Mechanical methods aim to enhance gas-water contact and mass transfer. The review evaluates how these approaches impact important parameters like gas consumption, hydrate formation rates, and CO2 recovery and separation from gas mixtures. It also considers the limitations and challenges of HBCC compared to conventional CO2 capture technologies.
The document discusses proposed improvements to the circulating water treatment system at NLC TPS II power plant. It analyzes water parameters from the current system and identifies high hardness, alkalinity, dissolved solids and oxygen that promote corrosion and scaling. A new treatment system is proposed using increased chlorine dosing to control microbes, along with corrosion and scale inhibitors. Annual chemical consumption and costs are estimated for different cycles of concentration to reduce specific water consumption below 3.5 m3/MWh. Improving the treatment process aims to control corrosion, scaling and fouling in the circulating water system.
This document summarizes research on using electrodialysis and reverse osmosis to recover dissolved organic carbon from seawater. The researchers developed a process to concentrate seawater using reverse osmosis, followed by electrodialysis to remove salt, producing a desalinated sample for analysis. Over 15 experiments were conducted using seawater and brackish water samples, recovering 60-90% of dissolved organic carbon. Preliminary results found differences in the recovered high molecular weight fraction compared to previous methods. The combined process allows treatment of large volumes of seawater samples for scientific study of marine dissolved organic carbon.
The document discusses the use of variant question papers for some of CIE's most popular assessments. It explains that CIE uses two closely related variants of some question papers to provide more past examination material to students. For each variant, there is a corresponding mark scheme and examiner's report. The document contains both variants of the materials so that all centers have access to them. It provides guidance on how to identify which variant a particular paper belongs to based on labels at the top of the page. Anyone with additional questions should contact CIE's customer service team.
The document discusses CIE's use of variant question papers for some popular assessments with large candidatures. It explains that while the content and question types remain the same, there are now two variants of the question paper, mark scheme, and principal examiner's report for one component. Centres will use only one variant, but this provides access to more past examination material. It includes a diagram showing the relationship between the question papers, mark schemes, and reports for the two variants. The document also provides contact information for questions about these changes.
The document discusses the use of variant question papers for some of CIE's most popular assessments. It explains that CIE uses two closely related variants of some question papers to provide more past examination material to students. For each variant, there is a corresponding mark scheme and examiner's report. The document contains both variants of the materials so that all centers have access to them. It provides information on how to identify which variant a particular paper belongs to based on labels at the top of the page. Anyone with additional questions should contact CIE customer services.
This document provides information about an advanced chemical engineering thermodynamics course, including:
1) The course covers basic definitions, concepts, relationships for pure components and mixtures including pvT relationships and thermodynamic property relationships.
2) Relevant textbooks are listed for reference.
3) Methods for determining pvT properties of pure components and mixtures are discussed, including experimental determination, databases, equations of state, and process simulators.
4) The Lydersen and Pitzer methods for corresponding states are summarized, which use critical compressibility factor and acentric factor respectively as third parameters to determine compressibility factor from reduced temperature and pressure.
The document describes experimental studies of two cylindrical latent heat energy storage systems (LHESS) using lauric acid as the phase change material (PCM). The first is a horizontal cylinder with one finned copper pipe passing through the center. The second is a vertical cylinder with two finned copper pipes allowing for simultaneous charging and discharging. Experiments were conducted to study the phase change behavior of the PCM and heat transfer processes during charging, discharging, and simultaneous charging/discharging. Results show natural convection plays an important role in melting and simultaneous charging/discharging but less so in solidification.
Gas hydrate
To prepare natural gas for sale, its undesirable components (water, H2S and CO2) must be removed. Most natural gas contains substantial amounts of water vapor due to the presence of connate water in the reservoir rock. At reservoir pressure and temperature, gas is saturated with water vapor
Preliminary Study on biogas production from POME by DBD plasmaTELKOMNIKA JOURNAL
A new technology to produce biogas using a dielectric barrier discharge (DBD) plasma system
from palm oil mill effluent (POME) was investigated. The batch experiments were examined at applied
voltages of 15, 20 and 25 kV. The results showed that the highest yields of hydrogen and methane were
achieved at an applied voltage of 25 kV after 1 hour were 2.42 and 1.32 mL/mL of POME, respectively.
The biogas was composed of 65% hydrogen and 35% methane. In order to make the results of this study
applicable to biogas plants, the effects of flowrate and consumed energy are important parameters that
should be further investigated in a future study.
Gas HydratesGas HydratesGas HydratesGas HydratesGas Hydratesminaapascal
This document discusses gas hydrates as an energy resource. It begins with an overview of the global energy situation and increasing demand. Gas hydrates are then defined as naturally occurring structures where gas molecules are trapped within ice crystals under certain pressure and temperature conditions. The document outlines the significant worldwide reserves of gas hydrates, particularly in ocean sediments, and different exploitation methods including depressurization, inhibitor injection, and thermal stimulation. Mathematical models for fluid flow, heat transfer, and species transport during gas hydrate dissociation are also presented. The document concludes that gas hydrates represent an important potential energy source and that further research is needed to safely exploit methane from hydrate reservoirs.
This document summarizes a study on the kinetics of methanol synthesis from carbon dioxide hydrogenation over copper-zinc oxide catalysts. Experiments were conducted in a fixed bed reactor between 200-230°C, 50-80 bar, and gas hourly space velocities of 7,800-23,400 h-1 using feeds with H2:CO2 ratios of 2-6 without CO. Kinetic parameters from a previous study were optimized to model the experimental data using a Langmuir–Hinshelwood–Hougen–Watson mechanism. The influences of catalyst support (alumina vs zirconia) and operating conditions on kinetics were examined. The goal was to determine optimized parameters to reliably scale-up the
The document presents a study on the hydrodynamic behavior of an external loop airlift reactor for two-phase systems. Experiments were conducted to determine the gas holdup and pressure drop characteristics of various electrolyte and solvent solutions at different concentrations and flow rates. The results show that gas holdup increases with superficial gas velocity and solvent concentration but decreases with electrolyte concentration, while pressure drop increases with gas velocity, liquid flow rate, and solution concentration.
The document summarizes an experiment studying factors that affect CO2 absorption in a NaOH solution. The experiment tested how absorption is affected by flow rate of CO2 gas, CO2 concentration, volume of NaOH solution, and pH. Absorption increased with lower flow rates, higher NaOH volumes, and higher pH. The results supported theories that more CO2 absorbs at higher pressures and NaOH concentrations. Future studies could optimize flow rates to maximize both absorption capacity and breakthrough time.
This document discusses various processes for separating and enriching the tritium isotope. It begins by introducing tritium isotope separation and some key concepts. It then describes several processes that have been used to enrich tritium for analytical purposes, including water electrolysis, water distillation, thermal diffusion, and permeation through membranes. The document also discusses processes that have been used to recover and enrich tritium from nuclear power plants, such as water distillation, thermal diffusion, adsorption, and chromatography. It emphasizes that effective tritium separation and control is important for both the nuclear power and potential fusion power industries.
This document summarizes a study on the thermal performance of a shell and tube heat exchanger using nanofluids. Finite volume modeling was used to analyze heat transfer and flow characteristics. Various nanofluids including Ag, Al2O3, CuO, SiO2, and TiO2 suspensions in water were tested and compared to pure water. The objectives were to analyze temperature profiles, heat transfer coefficients, pressure drops, and effectiveness. Results showed nanofluids had higher overall temperatures indicating more heat transfer compared to water alone. This study analyzed the potential for nanofluids to enhance heat exchanger performance.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
International Conference on NLP, Artificial Intelligence, Machine Learning an...gerogepatton
International Conference on NLP, Artificial Intelligence, Machine Learning and Applications (NLAIM 2024) offers a premier global platform for exchanging insights and findings in the theory, methodology, and applications of NLP, Artificial Intelligence, Machine Learning, and their applications. The conference seeks substantial contributions across all key domains of NLP, Artificial Intelligence, Machine Learning, and their practical applications, aiming to foster both theoretical advancements and real-world implementations. With a focus on facilitating collaboration between researchers and practitioners from academia and industry, the conference serves as a nexus for sharing the latest developments in the field.
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
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presentation.pptx
1. Formation kinetics of sII and sH gas
hydrates, surface phenomenon point
of view
AMIR ERFANI
SUPERVISOR: DR. F. VARAMINIAN
SEPTEMBER 2015
Semnan University
2. Scopes
1. Gas hydrate: an introduction
(Hydrate formers and hydrate structures, pros and cons)
2. Experimental
(Atmospheric and high pressure hydrate formations, pendant drop method)
3. Results and discussion
4. Conclusions and future plans
2
3. 1. Gas hydrate: an introduction
Gas hydrate or clathrate hydrates: crystalline ice-like solid [1-2]
Guest molecules are trapped in cages formed by water molecules
Formed at:
Low temperatures (slightly above freezing point of water)
High pressures
Guest molecules:
C1,C2,C3, CO2, H2S, …..
3
4. 1. Gas hydrate: an introduction
Gas hydrate Structures [3-4]:
1. sI: 46 water molecules, cages: 2 small (512) and 6 large (51262)
2. sII: 136 water molecules: 16 small (512 ) cages 8 large cages (51264).
3. sH: 34 water molecules: 3 small 512,
2 small ones of type 435663 and
one huge of type 51268
4
5. 1. Gas hydrate: an introduction
Structures:
the quest molecule define which structure is formed
The equilibrium pressure of hydrate formation is different for these structures
The water content is different!
5
sH gas hydrate
6. 1.Gas hydrate: an introduction
Why study of gas hydrates is of importance:
1. natural gas hydrates: potentially vast energy resource [1]
(6.4×1012 tonnes of methane is trapped on ocean floor)
2. cause problems for the petroleum industry [1,5]
(form inside gas pipelines, drilling operations)
3. Gas separation [6-7]
4. CO2 capture [8-9]
5. Transportation of natural gas or hydrogen [10-13]
6. Gas hydrate as cold storage material [14-17]
7. Desalination of water [18-20]
Why kinetics of hydrate formation is of importance??
Help us introducing new technologies!!!
6
7. 1.Gas hydrate: an introduction
Among these technologies we are concerned with:
Use of gas hydrate as a medium for
1. Gas transportation and storage: sH is best structure [21]
2. Cold storage material: hydrate that form at moderate conditions
7
8. 1. Gas hydrate: an introduction
The kinetics of sII and sH hydrate are poorly understood.
No account for promotion of sH hydrate in published literature
The promotion (and inhibition) mechanisms: not well understood
8
Kinetics of hydrate formation for
MCH/methane/ water system at 3°C
[11]
9. 1. Gas hydrate: an introduction
In promotion section we deal with surfactant!
Surfactant types : anionic, cationic, non-ionic [22-24]
Non-ionic surfactants: more environmental friendly and less toxic
Macroscopic properties of surfactants [25-26]
9
HLB =
𝑚𝑜𝑙𝑒 𝐸𝑂 ×44
𝐴𝑣𝑒𝑟𝑎𝑔𝑒.𝑚𝑜𝑙𝑒𝑐𝑢𝑙𝑎𝑟.𝑤𝑡
× 20
10. 1. Gas hydrate: an introduction
Our research goals:
A better understanding of hydrate formation and promotion mechanism
How surfactants affect the interfacial tension and hydrate formation
Help introducing hydrate based technologies
10
11. 2. Experimental
2.1. Atmospherics hydrate formation in stirred reactor
2.2. Atmospheric hydrate formation on subcooled cylinder
2.3. High pressure hydrate formation in stirred reactor
2.4. liquid-liquid interfacial tension measurements
2.5. Materials
11
12. 2. Experimental
2.1. Atmospherics hydrate formation in stirred
reactor
Mixture: 100 cc
Ratios: hydrate stoichiometric ratio
Stirrer speed: 550 rpm
Procedure
12
14. 2. Experimental
2.3 High pressure hydrate formation in stirred
reactor
600 cc stirred reactor
Controllable stirrer speed
Calibrated temperature and pressure transmitters
With 0.1°C and 0.1 bar accuracies
Stirrer speed: 650 rpm
Solution: 250 or 300 cc
14
15. 2. Experimental
2.3 High pressure hydrate formation in stirred reactor
15
Pressure vs. time for the system of water/MCH/Methane at 2°C in
presence of 1%w/wNPE6EO
16. 2. Experimental
2.4. liquid-liquid surface tension measurements
2.4 liquid-liquid surface tension measurements [27-29]
16
𝛾 =
∆𝜌𝑔𝑑𝑒
2
𝐻
1
𝐻
= 𝑓
𝑑𝑠
𝑑𝑒
e
s
d
d
S
0
1
2
2
3
3
4
1
B
S
B
S
B
S
B
S
B
H a
17. 2. Experimental
2.4. liquid-liquid surface tension measurements
Pendant drop apparatus:
1. Liquid pump
2. Pendant drop
3. Sessile bubble
4. Small cylinder
5. Gas supply
6. Digital microscope
7. Light source
8. 8,9,12: pressure and temperature transmitter
10. Temperature controlled bath
13. Drain
14. To vacuum pump
15. Computer
16. Needle valve
17
21. Methodology
Methodology:
Firstly the hydrate formation reactions are conducted
Secondly the interfacial tension of desired systems are measured
Finally the hydrate formation rates are compared with the interfacial tension datas.
21
22. 3. Results and discussion:
3.1. interfacial tension
CP/water system:
CP droplet in continuous water phase
Left: in presence of TritonX100,
Interfacial tension: 3.7 mN/m
Right: no surfactants,
interfacial tension: 31 mN/m
22
Needle outer diameter: 1.22 mm
23. 3. Results and discussion:
3.1. interfacial tension
CP/water system:
23
CP/water interfacial tension, surfactants at 1%w/w
26. 3. Results and discussion:
3.1. interfacial tension
Highest interfacial tension: MCP
Lowest interfacial tension: TBME
Lower interfacial tension: due to hydrogen bounding (ether
oxygen and water hydrogen)
At high temperatures: the hydrogen bounding less
important
26
27. 3. Results and discussion:
3.2. CP hydrate
Effect of surfactants on CP hydrate formation:
(Family of NPE)
Steeper slope: higher rate
27
28. 3. Results and discussion:
3.2. CP hydrate
Surfactants at 1% w/w
28
29. 3. Results and discussion:
3.2. CP hydrate
Effect of studied polymers:
29
30. 3. Results and discussion:
3.2. CP hydrate
best promoters : TritonX-100, NPE6EO and LAE8EO;
Rate : 1533% increase
Induction time: 0.04 of its original value
The rate is mass transfer controlled
30
Rate
(°C/60sec)
Induction time
(sec)
System
0.3
1244
No surfactant
2.8
94
LAE2EO
2.9
4
LAE3EO
3.9
41
LAE7EO
3.7
31
LAE8EO
4.6
56
TritonX100
4
7
NPE6EO
3.7
42
NPE10EO
0.6
113
NPE30EO
1.3
50
NPE40EO
2
50
EO/PO
copolymer
0.3
210
PEG 600
1.9
120
Tween40
31. 3. Results and discussion:
3.2. CP hydrate
On the promotion mechanism:
Bancroft's law: the phase which the emulsifier is more soluble is the continuous phase
of an emulsion
Best promoters: optimum O/W emulsifiers
31
32. 3. Results and discussion:
3.2. CP hydrate
Visual observations:
Hydrate are in form of aggregates
The hydrate formed in presence of surfactants: more slurry-ish
The surfactants can affect the particle adhesion forces
32
CP hydrate aggregates,
light microscopy 100X magnification left: the cyclopentane and water Right: addition of NPE6EO
33. 3. Results and discussion:
3.3. THF hydrate
THF hydrate formation
Mechanisms: Rayleigh number [30]
Ra=590
Thus: only conduction!
ρCp
𝜕T
𝜕t
=𝛻. k𝛻T
An enthalpy based heat transfer model is developed
33
Thickness of hydrate formed, T (out): 4°C
L
L
H
eq
i
L D
T
T
g
Ra
3
)
(
34. 3. Results and discussion:
3.4. THF hydrate
34
A. Thot=8.2 ℃ ,Tini=8.2℃ , Tcold=0.1 ℃, relative
absolute error:12.2%
B. Thot=Tini=6.7 ℃ ,Tcold=0.1 ℃, relative absolute
error: 8.6%
C. Tcold=3.5 ℃ , Thot=Tini=4.5, relative absolute
error: 12.1%
D. Tcold=2.35 ℃ , Thot=Tini=4.5 ℃, relative absolute
error:11.7%
E. Tcold=1.3 ℃ , Thot=Tini=4.5 ℃, relative absolute
error: 10.5%
F. Tcold=0.35 ℃ , Thot=Tini=4.5 ℃, relative absolute
error:11.3%
THF hydrate formation: (a soluble hydrate
former)Is heat transfer controlled!!!!
36. Results and discussion:
3.4. sH methane hydrate
First account for sH promotion:
Effect of TritonX-100
Much lower induction time
Higher rate
Single stage process
36
37. Results and discussion:
3.4. sH methane hydrate
Effect of other additives:
SDS in not a sH promoter
This might be due to affect of identical charge repulsion
37
38. Results and discussion:
3.4. sH methane hydrate
NPE6EO and Triton X-100:best promoters
The tritonX-100 also exhibit the lowest
interfacial tension
The induction time is lower to 0.04 of its
original value
Rate: 424% increase
38
Rate
(bar/3000sec)
Induction
time
(sec)
Surfactant
concentration
w/w
surfactant
System
2.5
50000
--
--
MCH+ water
4.7
12000
--
--
MCH+ water
(twice
stoichiometric
ratio)
12.2
2100
1%
TritonX100
MCH+ water
(twice
stoichiometric
ratio)
12.5
17100
1%
TritonX100
MCH+ water
12.2
16800
0.5%
TritonX100
MCH+ water
12.5
21100
0.25%
TritonX100
MCH+ water
10.2
12300
1%
LAE8EO
MCH+ water
12.3
4670
1%
NPE6EO
MCH+ water
10.6
2550
1%
EO/PO block
copolymer
MCH+ water
8.7
31000
1%
Tween40
MCH+ water
13.1
2150
0.5% + 0.5%
NPE6EO+
Tritonx100
MCH+ water
39. Results and discussion:
3.4. sH methane hydrate
MCP/methane water:
The sH hydrate does nor form in timescale of the experiment
(more than 16 hours)
Effect of NPE6EO :
39
Rate
(bar/3000sec)
Induction time
(sec)
Surfactant
concentration
w/w
surfactant
System
1.5
27100
--
--
MCP+ water
1.7
5420
--
--
MCP+ water
(twice
stoichiometric
ratio)
2.8
16500
1%
NPE6EO
MCP+ water
40. Results and discussion:
3.4. sH methane hydrate
MCP/methane water:
Effect of initial pressure:
The induction time is not pressure dependent!!
Higher pressures: higher rate!
For sI: induction time is pressure dependent!
The liquid/liquid solubility control the induction time
40
41. Results and discussion:
3.4. sH methane hydrate
Kinetics of TBME/methane/water
Effect of surfactants:
Two stage hydrate formation!
41
42. Results and discussion:
3.4. sH methane hydrate
Kinetics of three studied systems
42
In presence of 1% NPE6EO at 2°C
43. Results and discussion:
3.4. sH methane hydrate
The TBME is kinetically favorable
The MCH and MCP are thermodynamical favorable
Mixture of two large guest molecules
43
44. Conclusions:
NPE6EO, TritonX-100 and LAE8EO can significantly promote CP hydrate
formation kinetics: much higher interfacial surface
The presence of surfactant can lower the particle adhesion forces: more slurry-
ish
THF hydrate formation is a heat transfer controlled process due to its high
solubility in water
Proposed enthalpy based heat transfer model can easily predict THF hydrate
formation rate
44
45. Conclusions:
The CP/water MCP/water and MCH/water interfacial tension can be
lowered by an order of magnitude using non-ionic surfactants
While the EO/PO can increase the effective diffusivity of the CP in water,
anionic surfactant might lower the effective diffusivity
Mixed TBME/MCH and TBME/MCP systems are kinetically and
thermodynamically favorable systems
Presence of surfactants: can change kinetic path for sH hydrate formation
45
46. Future plans:
Experimental an modeling investigation of THF hydrate formation: falling
film
Study of rheology and particle adhesion force for THF,TBAB and CP
hydrate
with and without additives
Study of sH and sII hydrogen clathrate hydrate for hydrogen
transportation and storage
Study of hydrate formation in CP/methane/ water and CP/CO2/water
systems
46
47. References
1. Sloan Jr ED, Koh C.2007. Clathrate hydrates of natural gases. CRC.
2. Sloan ED. 2006.Fundamental principles and applications of natural gas hydrates, Nature.
3. Ripmeester, John A., S. Tse John, Christopher I. Ratcliffe, and Brian M. Powell. 1987. A new clathrate hydrate structure. Nature, 325:
135-136.
4. Susilo, Robin, Saman Alavi, Igor L. Moudrakovski, Peter Englezos, and John A. Ripmeester. 2009. Guest–Host Hydrogen Bonding in
Structure H Clathrate Hydrates. ChemPhysChem 10: 824-829.
5. Naeiji Parisa, Akram Arjomandi, and Farshad Varaminian.2014. Amino acids as kinetic inhibitors for tetrahydrofuran hydrate formation:
experimental study and kinetic modeling. Journal of Natural Gas Science and Engineering, 21: 64-70.
6. Eslamimanesh A, Mohammadi AH, Richon D, Naidoo P, Ramjugernath D. 2012. Application of gas hydrate formation in separation
processes: A review of experimental studies. The Journal of Chemical Thermodynamics.
7. Naeiji, Parisa, Mona Mottahedin, and Farshad Varaminian. 2014. Separation of methane–ethane gas mixtures via gas hydrate
formation. Separation and Purification Technology.
8. ZareNezhad Bahman, and Mona Mottahedin. 2012. A rigorous mechanistic model for predicting gas hydrate formation kinetics: the case
of CO 2 recovery and sequestration. Energy Conversion and Management, 53: 332-336
47
48. References
9. Jerbi, Salem, Anthony Delahaye, Laurence Fournaison, and Philippe Haberschill. 2010. Characterization of CO2 hydrate formation and
dissociation kinetics in a flow loop. International journal of refrigeration.
10. Hao W, Wang J, Fan S, Hao W.2008. Evaluation and analysis method for natural gas hydrate storage and transportation
processes", Energy conversion and management.
11. Mazraeno M. Seyfi, and Farshad Varaminian. 2013. Experimental and modeling investigation on structure H hydrate formation kinetics"
Energy Conversion and Management.
12. Karimi Reza, Farshad Varaminian, Amir A. Izadpanah, and Amir H. Mohammadi. 2014. Effects of two surfactants sodium dodecyl sulfate
(SDS) and polyoxyethylene (20) sorbitan monopalmitate (Tween (R) 40) on ethane hydrate formation kinetics: Experimental and
modeling studies. Journal of Natural Gas Science and Engineering.
13. Roosta H., S. Khosharay, and F. Varaminian. 2013. Experimental study of methane hydrate formation kinetics with or without additives
and modeling based on chemical affinity. Energy Conversion and Management.
14. Darbouret, Myriam, Michel Cournil, and Jean-Michel Herri. 2005. Rheological study of TBAB hydrate slurries as secondary two-phase
refrigerants. International Journal of Refrigeration.
15. Li, Gang, Yunho Hwang, and Reinhard Radermacher.2012.Review of cold storage materials for air conditioning application. International
journal of refrigeration.
16. Tomlinson, John J.1982. Heat-pump cool storage in a clathrate of freon. 1982. Presented at the Energy Storage Contractors Rev.
Meeting, Arlington.
48
49. References
17. Ogoshi, Hidemasa, and Shingo Takao. 2004.Air-conditioning system using clathrate hydrate slurry." JFE Tech. Rep 3.
18. Javanmardi, M. Moshfeghian.2003. Energy consumption and economic evaluation of water desalination by hydrate phenomenon.
Applied thermal engineering.
19. Karamoddin Maryam, and Farshad Varaminian. 2014. Study on the growth process of HCFC141b hydrate in isobaric system by a
macroscopic kinetic model. International Journal of Refrigeration.
20. Karamoddin Maryam, Farshad Varaminian.2014. The modeling of hydrate growth kinetics in tetrahydrofuran–water mixture based on
subcooling driving force. Journal of Industrial and Engineering Chemistry.
21. Ohmura Ryo, Shigetoyo Kashiwazaki, Saburo Shiota, Hideyuki Tsuji, and Yasuhiko H. Mori.2002.Structure-I and structure-H hydrate
formation using water spraying. Energy & Fuels, 16: 1141-1147.
22. Rosen M.J. 1989. Surfactants and interfacial phenomena, John Wiley and Sons,
23. Butt H.J., Graf K, Kappl M., 2003.Physics and chemistry of interfaces, Wiley-VCH.
24. Schuster D. 1987.Encyclopedia of Emulsion Technology: Basic theory, measurement, applications. Vol. 3. CRC Press.
49
50. References
25. Amarda K.V., Bonnell B.W., Maranas C.D., Nagarajan R. 1999. Design of surfactant solutions with optimal macroscopic properties.
Computers & Chemical Engineering.
26. Griffin WC.1946. Classification of surface-active agents by HLB", Cosmetic Chemists.
27. Bikkina, Prem Kumar, O. Shoham, and R. Uppaluri. 2011. Equilibrated Interfacial Tension Data of the CO2–Water System at High
Pressures and Moderate Temperatures. Journal of Chemical & Engineering Data, 10: 3725-3733.
28. Yakhshi Tafti, Ranganathan Kumar, and Hyoung J. Cho. 2001. Measurement of Surface Interfacial Tension as a Function of
Temperature Using Pendant Drop Images. International Journal of Optomechatronics, 5: 393-403.
29. Kahl, Heike, Tino Wadewitz, and Jochen Winkelmann. 2003. Surface tension of pure liquids and binary liquid mixtures. Journal of
Chemical & Engineering Data 48: 580-586.
30. Getling, Alexander V.1998. Rayleigh-Bénard convection: structures and dynamics”, World Scientific.
50
51. Thank you for your attention
(a.erfani@students.semnan.ac.ir)
51
53. Results and discussion:
3.4. sH methane hydrate
Induction time is lowere to 0.15 of its original value
Rate: 162% increase
53
Rate
(bar/3000sec)
Induction time
(sec)
Surfactant
concentration
w/w
surfactant
System
11
670
--
--
TBME+ water
17
420
--
--
TBME+ water
(twice
stoichiometric
ratio)
18.8
68
1%
TritonX100
TBME+ water
(twice
stoichiometric
ratio)
17.8
100
1%
TritonX100
TBME+ water
12.4
80
1%
LAE8EO
TBME+ water
11.6
150
1%
NPE6EO
TBME+ water
Editor's Notes
Rate
(bar/3000sec)
Induction time
(sec)
Surfactant concentration w/w
surfactant
System
11
670
--
--
TBME+ water
17
420
--
--
TBME+ water
(twice stoichiometric ratio)
18.8
68
1%
TritonX100
TBME+ water
(twice stoichiometric ratio)
17.8
100
1%
TritonX100
TBME+ water
12.4
80
1%
LAE8EO
TBME+ water
11.6
150
1%
NPE6EO
TBME+ water
Rate
(bar/3000sec)
Induction time
(sec)
Surfactant concentration w/w
surfactant
System
11
670
--
--
TBME+ water
17
420
--
--
TBME+ water
(twice stoichiometric ratio)
18.8
68
1%
TritonX100
TBME+ water
(twice stoichiometric ratio)
17.8
100
1%
TritonX100
TBME+ water
12.4
80
1%
LAE8EO
TBME+ water
11.6
150
1%
NPE6EO
TBME+ water