scholarly journals Analysis of gas preparation processes for improvement of gas transportation technology

2021 ◽  
pp. 48-56
Author(s):  
Abdulaga Gurbanov ◽  
Ijabika Sardarova ◽  
Javida Damirova
Keyword(s):  
Liquid Phase ◽  
Gas Flow ◽  
Low Pressure ◽  
Dew Point ◽  
Offshore Platforms ◽  
Regression Equations ◽  
Gas Temperature ◽  
Working Pressure ◽  
Phase Displacement ◽  
Study Results

At production, collection and transport of low – pressure gas to deep water offshore platforms in sea conditions because of thermodynamic indices change in the system, complications are generated in connection with liquid phases – separation. These complications disturb normal operational well behavior, gas preparation unit and trunk (main) pipeline conditions. As a result of these phenomena high – volume losses of gas, gas condensate and chemical reagent take place. In the process of testing, the following process parameters were determined: pressure, gas temperature, facility performance, regeneration temperature, amount of absorbent injected into the gas flow, concentration of regenerated and saturated absorbent, dry gas dew point and so on. In the process of investigating the effect of the amount of inhibitor on the degree of corrosion prevention, hydrate formation and salt deposit at the facilities, regression equations. That is why, to guarantee uninterrupted transportation of low-pressure gas in field conditions, new methods are required for these phenomena prevention. On the basis of field study results some variants of calculation were given to increase efficiency of low-pressure gas transportation system in offshore oil and gas field’s conditions. Results of high-pressure gas optimal working pressure calculation for precipitated liquid phase displacement at low-pressure petroleum gas transportation to deepwater offshore platforms are shown in the article. As well, method for precipitated liquid phase displacement from low-pressure gas pipeline with usage of high-viscosity elastic gelling compositions on the basis of domestic petrochemical products

Numerical study of the effect of gas flow in low pressure inductively coupled Ar/N2 plasmas

Open Physics ◽  
2012 ◽  
Vol 10 (4) ◽  
Author(s):  
Lizhu Tong
Keyword(s):  
Gas Flow ◽  
Numerical Study ◽  
Low Pressure ◽  
Input Power ◽  
Gas Flows ◽  
Gas Temperature ◽  
Plasma Discharges ◽  
Power Losses ◽  
Inductively Coupled ◽  
Plasma Species

AbstractThe effect of gas flow in low pressure inductively coupled Ar/N2 plasmas operating at the rf frequency of 13.56 MHz and the total gas pressure of 20 mTorr is studied at the gas flows of 5–700 sccm by coupling the plasma simulation with the calculation of flow dynamics. The gas temperature is 300 K and input power is 300 W. The Ar fractions are varied from 0% to 95%. The species taken into account include electrons, Ar atoms and their excited levels, N2 molecules and their seven different excited levels, N atoms, and Ar+, N+, N2 +, N4 + ions. 51 chemical reactions are considered. It is found that the electron densities increase and electron temperatures decrease with a rise in gas flow rate for the different Ar fractions. The densities of all the plasma species for the different Ar fractions and gas flow rates are obtained. The collisional power losses in plasma discharges are presented and the effect of gas flow is investigated.

INFLUENCE OF FORCED CONVECTION IN LIQUID INSIDE THE TIN ON DURATION OF STERILIZATION IN THE COURSE OF FISH PROCESSING

2017 ◽  
pp. 137-144
Author(s):  
Gennadiy Valentinovich Alexeev ◽  
Elena Igorevna Verboloz
Keyword(s):  
High Temperature ◽  
Liquid Phase ◽  
Forced Convection ◽  
Thermal Process ◽  
Processing Time ◽  
Fish Processing ◽  
Study Results ◽  
Equipment Modernization ◽  
Bottom To Top

The article focuses on the process of intensive mixing of liquid phase in the tin during high-temperature sterilization, i.e. sterilization when temperature of the heat carrier reaches 150-160°C. It has been stated that for intensification of the thermal process during sterilization of tinned fish with liquid filling it is preferable to turn a tin from bottom to top. This operation helps to increase the driving power of the process and to shorten warming time. Besides, high-temperature sterilization carried out according to experimental modes, where the number of tin turnovers is calculated, greatly shortens processing time and improves quality of the product. In this case there is no superheating, all tins are evenly heated. The study results will contribute to equipment modernization and to preserving valuable food qualities.

scholarly journals Experimental Study of Bubble Formation from a Micro-Tube in Non-Newtonian Fluid

Micromachines ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 71
Author(s):  
Georgia Kontaxi ◽  
Yorgos G. Stergiou ◽  
Aikaterini A. Mouza
Keyword(s):  
Liquid Phase ◽  
Shear Rate ◽  
Newtonian Fluid ◽  
Gas Flow ◽  
Bubble Formation ◽  
Release Time ◽  
Internal Diameter ◽  
Asymptotic Value ◽  
Shear Thinning Fluids ◽  
A Value

Over the last few years, microbubbles have found application in biomedicine. In this study, the characteristics of bubbles formed when air is introduced from a micro-tube (internal diameter 110 μm) in non-Newtonian shear thinning fluids are studied. The dependence of the release time and the size of the bubbles on the gas phase rate and liquid phase properties is investigated. The geometrical characteristics of the bubbles are also compared with those formed in Newtonian fluids with similar physical properties. It was found that the final diameter of the bubbles increases by increasing the gas flow rate and the liquid phase viscosity. It was observed that the bubbles formed in a non-Newtonian fluid have practically the same characteristics as those formed in a Newtonian fluid, whose viscosity equals the asymptotic viscosity of the non-Newtonian fluid, leading to the assumption that the shear rate around an under-formation bubble is high, and the viscosity tends to its asymptotic value. To verify this notion, bubble formation was simulated using Computational Fluid Dynamics (CFD). The simulation results revealed that around an under-formation bubble, the shear rate attains a value high enough to lead the viscosity of the non-Newtonian fluid to its asymptotic value.

Study on the Deposition Profile Characteristics in the Micron-Scale Trench Using Direct Simulation Monte Carlo Method

1998 ◽  
Vol 120 (2) ◽  
pp. 296-302 ◽  
Author(s):  
Masato Ikegawa ◽  
Jun’ichi Kobayashi ◽  
Morihisa Maruko
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Boundary Conditions ◽  
Gas Flow ◽  
Direct Simulation Monte Carlo ◽  
Low Pressure ◽  
Sputter Deposition ◽  
Direct Simulation ◽  
Simulation Monte Carlo ◽  
Profile Characteristics

As integrated circuits are advancing toward smaller device features, step-coverage in submicron trenches and holes in thin film deposition are becoming of concern. Deposition consists of gas flow in the vapor phase and film growth in the solid phase. A deposition profile simulator using the direct simulation Monte Carlo method has been developed to investigate deposition profile characteristics on small trenches which have nearly the same dimension as the mean free path of molecules. This simulator can be applied to several deposition processes such as sputter deposition, and atmospheric- or low-pressure chemical vapor deposition. In the case of low-pressure processes such as sputter deposition, upstream boundary conditions of the trenches can be calculated by means of rarefied gas flow analysis in the reactor. The effects of upstream boundary conditions, molecular collisions, sticking coefficients, and surface migration on deposition profiles in the trenches were clarified.

Behavior of Radial Incompressible Flow in Pneumatic Dimensional Control Systems

2003 ◽  
Vol 125 (5) ◽  
pp. 843-850 ◽  
Author(s):  
G. Roy ◽  
D. Vo-Ngoc ◽  
D. N. Nguyen ◽  
P. Florent
Keyword(s):  
Gas Flow ◽  
Flow Behavior ◽  
Pressure Gauge ◽  
Axisymmetric Flow ◽  
Low Pressure ◽  
Industrial Applications ◽  
Nozzle Geometry ◽  
Machined Surface ◽  
Flow Area ◽  
Simpler Algorithm

The application of pneumatic metrology to control dimensional accuracy on machined parts is based on the measurement of gas flow resistance through a restricted section formed by a jet orifice placed at a small distance away from a machined surface. The backpressure, which is sensed and indicated by a pressure gauge, is calibrated to measure dimensional variations. It has been found that in some typical industrial applications, the nozzles are subject to fouling, e.g., dirt and oil deposits accumulate on their frontal areas, thus requiring more frequent calibration of the apparatus for reliable service. In this paper, a numerical and experimental analysis of the flow behavior in the region between an injection nozzle and a flat surface is presented. The analysis is based on the steady-state axisymmetric flow of an incompressible fluid. The governing equations, coupled with the appropriate boundary conditions, are solved using the SIMPLER algorithm. Results have shown that for the standard nozzle geometry used in industrial applications, an annular low-pressure separated flow area was found to exist near the frontal surface of the nozzle. The existence of this area is believed to be the cause of the nozzle fouling problem. A study of various alternate nozzle geometries has shown that this low-pressure recirculation area can be eliminated quite readily. Well-designed chamfered, rounded, and reduced frontal area nozzles have all reduced or eliminated the separated recirculation flow area. It has been noted, however, that rounded nozzles may adversely cause a reduction in apparatus sensitivity.

Abstract W P302: Assessment of a New Method of Warfarin Management vs the New Oral Anticoagulants and Conventional Warfarin Management in Atrial Fibrillation

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Henry I Bussey ◽  
Edith Nutescu
Keyword(s):  
Atrial Fibrillation ◽  
Oral Anticoagulants ◽  
New Oral Anticoagulants ◽  
Target Range ◽  
Regression Equations ◽  
Major Event ◽  
Cost Avoidance ◽  
Study Results ◽  
Event Rates ◽  
The Impact

PURPOSE: To assess the impact of International Normalized Ratio (INR) self testing and online remote monitoring and management (STORM2) on clinical events and costs vs. traditional warfarin management and the new oral anticoagulants (NOACs) in atrial fibrillation (AF). METHODS: Seven STORM2 trials had a weighted mean INR time in the target range (TTR) of 77.2%. Thromboembolism (TE) and major bleeding (MB) rates at 30%, 45%, 55%, 65%, and 75% TTR were calculated using linear regression equations from a systematic review of 38 AF studies. MB = 10.104 - 0.120x[TTR], (p = 0.004) and TE = 8.313 - 0.098x[TTR], (p = 0.03). MB and TE rates were sub-divided based on the distribution in the NOAC trials. TTR-based mortality was calculated based on a 6%/yr rate multiplied by the adjusted relative risks from a data base analysis of approximately 38,000 AF patients. Projected event rates at 75% TTR, expressed as number per 1,000 patient-years, were compared to event rates at lower TTR ranges and to rates reported in the NOAC trials. Differences in major event rates were used to calculate cost avoidance. RESULTS: Projected event rates with STORM2 (TTR of 75%) when compared to “conventional ” TTR of 55% to 65% were 64% to 71% lower for MB, 47% to 64% lower for TE, and 47% to 57% lower for mortality. Compared to the NOAC study results, the projected rates were 48% to 70% lower for MB, 41% to 66% lower for TE, and 40% to 53% lower for mortality. Projected cost avoidance was $10.4 million vs. a TTR of < 30%, $2.2 million vs. a TTR of 65%; and from $1.4 to $3.1 million vs the NOACs. Costs of “other” MB and TE , drug costs, and monitoring costs were not included in the estimates. CONCLUSIONS: STORM2 management of warfarin is projected to produce a 50% or greater reduction in major event rates with a cost avoidance of $1.4 to $10.4 million per 1,000 patients per year. CLINICAL IMPLICATIONS: STORM2 management may transform the safety and efficacy of anticoagulation for the millions of people with AF while substantially reducing costs. These findings warrant randomized, prospective trials in AF and other indications for anticoagulation.

scholarly journals Ethylene Glycol Regeneration Plan: A Systematic Approach to Troubleshoot the Common Problems

2013 ◽  
Vol 27 ◽  
pp. 21-26 ◽  
Author(s):  
Md Emdadul Haque
Keyword(s):  
Ethylene Glycol ◽  
Gas Flow ◽  
Salt Content ◽  
Dew Point ◽  
Circulation Rate ◽  
Water Volume ◽  
Processing Plant ◽  
Regeneration System ◽  
Column Temperature ◽  
Flow Rates

Mono Ethylene Glycol (MEG) is used primarily at low-temperature processing plant for extracting natural gas liquids. Typically a physical process plant comprises with gas dehydration system which allows for physical separation of water saturated gas by simple dew point depression and water condensation brought about by chilling from cross exchange with propane refrigerant. The resultant wet gas is prevented from freezing by injection of liquid desiccants to inhibit hydrate formation. The resulting dehydrated gas stream will have a dew point preciously equal to the saturated water volume of the gas at its coolest temperature. Mono Ethylene Glycol has been chosen as hydrate inhibitor because of its low volatility, low toxicity, low flammability, good thermodynamic behavior, and simple proven technology requirement and availability. But it has two common characteristic problems in regeneration plant that is fouling of equipment by iron carbonate, Ca+2/Mg+2 salt deposits and cross contamination of MEG and condensate contamination. MEG in condensate causes condensate specification problems, fouling of condensate stabilization equipment and contamination of wastewater streams. Condensate in MEG causes stripping effect due to condensate vaporization, lower operating temperature, higher MEG purities, and contamination of wastewater streams from MEG Regeneration system and burping of column due to condensate buildup. Another common problem is glycol losses due to carryover with dehydrated gas and which finally accumulates in pipelines and causes corrosion. Other reasons of glycol losses are higher column temperature, foaming, leaks at pump or pipe fittings, operated with excessive gas flow rates and rapid changes in gas flow rates. Column Flooding occurred if feed glycol circulation rate exceeded design limit and it does not allow proper separation of glycol and water separator and much glycol losses through vent line. This paper presents an experimental study of glycol losses. Effort has been made to investigate the causes and the study suggests some mitigation plans. Current study suggests the efficiency of the dehydration process depends on a large extent on the cleanliness of the glycol and the regular monitoring of glycol parameters such as glycol concentration, hydrocarbon content, salt content, solids content, pH stabilization, iron content, foaming tendency etc. Losses due to vaporization from reboiler can be minimized by adjusting operating parameters. By developing monitoring procedure and periodic maintenance about 90% operating problems of Glycol Regeneration Plant can be reduced. DOI: http://dx.doi.org/10.3329/jce.v27i1.15853 Journal of Chemical Engineering, IEB Vol. ChE. 27, No. 1, June 2012: 21-26

scholarly journals Diagnostics of low-pressure capacitively coupled RF discharge argon plasma

2019 ◽  
Vol 13 (27) ◽  
pp. 76-82
Author(s):  
Kadhim A. Aadim
Keyword(s):  
Electron Temperature ◽  
Electron Density ◽  
Langmuir Probe ◽  
Gas Flow ◽  
Low Pressure ◽  
Gas Pressure ◽  
Rf Discharge ◽  
Electrode Gap ◽  
Probe Characteristic ◽  
Capacitively Coupled

Low-pressure capacitively coupled RF discharge Ar plasma has been studied using Langmuir probe. The electron temperature, electron density and Debay length were calculated under different pressures and electrode gap. In this work the RF Langmuir probe is designed using 4MHz filter as compensation circuit and I-V probe characteristic have been investigated. The pressure varied from 0.07 mbar to 0.1 mbar while electrode gap varied from 2-5 cm. The plasma was generated using power supply at 4MHz frequency with power 300 W. The flowmeter is used to control Argon gas flow in the range of 600 standard cubic centimeters per minute (sccm). The electron temperature drops slowly with pressure and it's gradually decreased when expanding the electrode gap. As the gas pressure increases, the plasma density rises slightly at low gas pressure while it drops little at higher gas pressure. The electron density decreases rapidly with expand distances between electrodes.

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