Corrigendum to ‘Online monitoring, filtering, blocking ….What is the difference? Where to draw the line?’ [2013] 29 CLSR 702–712

2014 ◽  
Vol 30 (2) ◽  
pp. 223
Author(s):  
Sophie Stalla-Bourdillon
Keyword(s):  
Online Monitoring ◽  
The Difference

Downhole Heating Technology – New Solution for Paraffinic Wells

2021 ◽  
Author(s):  
Mihaela Vlaicu ◽  
Vasile Marius Nae ◽  
Patrick Christian Buerssner ◽  
Stefan Liviu Firu ◽  
Natalya Logashova
Keyword(s):  
Technology Implementation ◽  
Online Monitoring ◽  
New Technology ◽  
Internal Diameter ◽  
Technology Application ◽  
Production Wells ◽  
The Difference ◽  
Wax Crystallization ◽  
Heating Technology ◽  
Production Losses

Abstract Paraffin represents one of the main case of failures and production losses which facing the entire oil industry. Prevention of paraffin deposition on the subsurface/surface equipment can be achieved by keeping the paraffin dissolved in crude oil or minimizing the adhesion or aggregation process of wax crystals. The paraffin problems which occur, conduct to gradual reduction of the tubular and pipelines internal diameter, restriction or valves blockages, and reduce the equipment capacity until the production is stop. Problems due to paraffin deposition varies and is different according with each commercial field, sometime the difference is from a well to well which producing from the same reservoir with different consistency. How we shall proceed? Before or after paraffin is field on the equipment? How could be avoid the future paraffin deposition? How long the selected method is proper for well ? The decision represents a combination based on oil's chemical & physical characteristics, well's behavior, method selected for prevention or elimination and combined with economic analysis and field experience. The paraffin inhibition applying is a common practice in OMV Petrom, which cover majority of the production wells. For the special wells, which the paraffin inhibition didn't provided satisfying results (multiple intervention due to paraffin deposition) was selected the Down Hole Heating technology (DHH) which was successfully tested in our company since 2014 thanks according with the yearly New Technology Program. The operating principle consists in heating the fluid volume from tubing using the heating cable which can be installed inside tubing, for NF and ESP wells or outside tubing for SRP or PCP wells. The cable is designed and located at the interval of wax crystallization appearance and heats the fluid to the temperature higher than the wax crystallization point (WAT). Since then, the DHH technology had an upward course, proven by high run life (highest value 2500 days / average 813 days) of the technology at the total 47 wells equipped, until this moment. Based on the successful results, recorded of 64% of old production wells equipped, it was decided to apply the technology at first completion of the new wells (36%), thus ensuring the protection of the new equipment. The paper offers an overview of DHH technology implementation, achievements, benefits and online monitoring of technology implementation starting with 2014 until today. The total impact shown a decreasing of no.of failures with 73,8%, the cost of intervention with 76,5%. The production losses decreased only with 5%, which certifies the fact that the technology helping production maintaining during the exploitation in comparison with production losses due paraffin issues recorded at wells without equipped with DHH technology. During 6 years of down hole heating technology application were developed candidate selection decision tree, monitoring the electrical efficiency, using the adaptability capacity of the technology from one well to another and integrate the temperature parameters in online monitoring system as part of digitalization concept of OMV Petrom, aspects which will be present in this article.

scholarly journals Precision Prediction of Knitted Fabric Loop Length Through Online Monitoring of Yarn Input Tension and Course Length-A Mathematical Approach for Circular Weft Knitting With Positive Storage Feeding

2017 ◽  
Vol 13 (30) ◽  
pp. 463
Author(s):  
A.K.M. Mobarok Hossain ◽  
Abu Rayhan Md. Ali
Keyword(s):  
Online Monitoring ◽  
Knitted Fabric ◽  
Loop Length ◽  
Mathematical Approach ◽  
Feed System ◽  
P Values ◽  
Experimental Part ◽  
The Difference ◽  
Course Length ◽  
T Values

A model in the form of an equation has been developed based on the mechanical consideration of yarn during dynamic circular weft knitting process that runs with positive storage feed system. The predicted course length through this model has been compared with that found from actual fabric by a recognized apparatus, i.e. HATRA Course Length Tester. The ttest was carried out over the obtained results for statistical analysis purpose. It was observed that for spun polyester knitted fabric, as used in the experimental part, the model worked very effectively through precision prediction by showing very low average mean difference in predicted course length from that measured from the actual fabric. The t-values and corresponding p-values proved the difference between the predicted and actual results statistically significant and thus opened the scope for further investigation and calibration.

Damage Detection of Pipes Based on PVDF

2012 ◽  
Vol 198-199 ◽  
pp. 158-161 ◽  
Author(s):  
Yu Xiang Zhang ◽  
Yun Zhou ◽  
Fu Hou Xu ◽  
Hua Cheng Li
Keyword(s):  
Finite Element Method ◽  
Polyvinylidene Fluoride ◽  
Online Monitoring ◽  
Detection Method ◽  
Mechanical Impedance ◽  
Mean Square ◽  
Mean Square Deviation ◽  
The Finite Element Method ◽  
Damage Extent ◽  
The Difference

To detect the pipes, this paper introduces the electro-mechanical impedance (EMI) method into online monitoring for the pipes. The pipes model with a Polyvinylidene Fluoride (PVDF) bonded on it is built. The finite element method is employed to analyze the electro-mechanical impedance of the PVDF, the conductance curves of PVDF are obtained with different damaging phase of the pipes, the root-mean-square deviation (RMSD) is used to assess the damage extent. The result indicates that EMI as a new detection method is effective in identifying the existence and severity of cracks in pipes. As the corrosion area increases, the difference of conductance curves becomes more obvious and the RMSD becomes larger.

Online Computing Model of Temperature Field of Turbine Rotor

2006 ◽  
Author(s):  
Qing He ◽  
Dongmei Du ◽  
Yuesheng Chen
Keyword(s):  
Temperature Field ◽  
Finite Difference Method ◽  
Boundary Conditions ◽  
Axisymmetric Problem ◽  
Online Monitoring ◽  
Turbine Rotor ◽  
Two Dimension ◽  
Computing Model ◽  
The Finite Difference Method ◽  
The Difference

Computation of temperature field of turbine rotor is a two-dimension axisymmetric problem. A two-dimension computing model of rotor temperature field is obtained by the analysis and simplification of rotor geometry structure and boundary conditions. The finite difference method is used to compute two-dimension temperature field of turbine rotor in this paper, which has enough precision and low amount of computation for online monitoring. By simplifying the structure and boundary conditions of turbine rotor, the fifteen node types of rotor are obtained. The difference calculating formulas for all node types are given. According to the model and difference formulas, an online computing program of temperature field of turbine rotor has been developed and applied to a 200MW turbine. Color cloud picture of temperature field of turbine rotor is released online via Internet.

The Origin of the Moon

1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
The Moon ◽  
The Earth ◽  
The Difference ◽  
Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

Influence of Cell Wall Composition on the Fossilisation of Bacteria and the Implications for the Search for Early Life Forms

1997 ◽  
Vol 161 ◽  
pp. 491-504 ◽  
Author(s):  
Frances Westall
Keyword(s):  
Cell Wall ◽  
Life Forms ◽  
Cation Binding ◽  
Positive Bacterium ◽  
Gram Positive ◽  
Gram Positive Bacteria ◽  
Transmission Electron ◽  
Hydrothermal Sediments ◽  
Identification Of Bacteria ◽  
The Difference

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.

Structuring, Motions and Shapes of Corona Emission Line Profiles

1994 ◽  
Vol 144 ◽  
pp. 421-426
Author(s):  
N. F. Tyagun
Keyword(s):  
Emission Line ◽  
Filling Factor ◽  
Direct Relationship ◽  
Coronal Plasma ◽  
Line Of Sight ◽  
Line Profiles ◽  
The Difference ◽  
Yellow Line ◽  
Red Line

AbstractThe interrelationship of half-widths and intensities for the red, green and yellow lines is considered. This is a direct relationship for the green and yellow line and an inverse one for the red line. The difference in the relationships of half-widths and intensities for different lines appears to be due to substantially dissimilar structuring and to a set of line-of-sight motions in ”hot“ and ”cold“ corona regions.When diagnosing the coronal plasma, one cannot neglect the filling factor - each line has such a factor of its own.

Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

1982 ◽  
Vol 40 ◽  
pp. 74-75
Author(s):  
Jules S. Jaffe ◽  
Robert M. Glaeser
Keyword(s):  
Purple Membrane ◽  
Data Set ◽  
High Resolution Data ◽  
X Ray ◽  
X Ray Crystallography ◽  
Fourier Techniques ◽  
Versus Protein ◽  
The Difference ◽  
Difference Fourier ◽  
Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

Destruction of Actin Filaments by Osmium Tetroxide

1977 ◽  
Vol 35 ◽  
pp. 466-467
Author(s):  
P. Maupin-Szamier ◽  
T. D. Pollard
Keyword(s):  
Actin Filaments ◽  
Time Course ◽  
Osmium Tetroxide ◽  
Rabbit Muscle ◽  
Muscle Actin ◽  
Sodium Phosphate Buffer ◽  
Transmission Electron ◽  
The Difference ◽  
Rates Of Decay ◽  
Short Time

We have studied the destruction of rabbit muscle actin filaments by osmium tetroxide (OSO4) to develop methods which will preserve the structure of actin filaments during preparation for transmission electron microscopy.Negatively stained F-actin, which appears as smooth, gently curved filaments in control samples (Fig. 1a), acquire an angular, distorted profile and break into progressively shorter pieces after exposure to OSO4 (Fig. 1b,c). We followed the time course of the reaction with viscometry since it is a simple, quantitative method to assess filament integrity. The difference in rates of decay in viscosity of polymerized actin solutions after the addition of four concentrations of OSO4 is illustrated in Fig. 2. Viscometry indicated that the rate of actin filament destruction is also dependent upon temperature, buffer type, buffer concentration, and pH, and requires the continued presence of OSO4. The conditions most favorable to filament preservation are fixation in a low concentration of OSO4 for a short time at 0°C in 100mM sodium phosphate buffer, pH 6.0.

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