Role of Propane, Methane and Oil Viscosity in Enhancing the Foamy Oil Phenomenon and Performance of Cyclic Solvent Injection (CSI); Experimental Studies

2017 ◽  
Author(s):  
A. Ahadi ◽  
F. Torabi ◽  
A. Abedini
SPE Journal ◽  
2019 ◽  
Vol 24 (06) ◽  
pp. 2695-2710
Author(s):  
Hongze Ma ◽  
Gaoming Yu ◽  
Yuehui She ◽  
Yongan Gu

Summary In this paper, we formulated an analytical material–balance model (MBM) to predict cumulative heavy–oil and gas-production data, as well as the average reservoir pressures, during the primary production and subsequent cyclic solvent injection (CSI) in a heavy–oil reservoir. The theoretical MBM considers the nonequilibrium foamy–oil phase behavior and foamy–oil flow by invoking two kinetic equations with nucleation and decay coefficients. In addition, we conducted four laboratory sandpack tests of the primary production and subsequent CSI to validate the new production model. It was found that the predicted cumulative heavy–oil production data and average reservoir pressures agreed reasonably well with the measured data during the primary production and subsequent CSI. However, there were large discrepancies between the predicted and measured cumulative gas-production data in the CSI owing to its strong gas channeling, which is a major technical issue to be studied further. Moreover, dissolved CH4 in the heavy oil became dispersed CH4 bubbles more quickly when the nucleation coefficient was larger at a higher pressure–drawdown rate or in less–viscous heavy oil. The foamy heavy oil with dispersed CH4 bubbles was more stable when the decay coefficient was smaller at a higher pressure–drawdown rate or in more–viscous heavy oil. It was also found that the foamy–oil isothermal compressibility increased by 10 to 1,000 times and that the dispersed–gas percentage in the foamy oil could reach as high as 14 vol% during the primary production. The foamy–oil viscosity was reduced by 36 to 55%, and the solution CH4/heavy–oil ratio was decreased by 41 to 76% at the end of the CSI.


Author(s):  
D. E. Newbury ◽  
R. D. Leapman

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).


2017 ◽  
Vol 16 (2) ◽  
pp. 61-76 ◽  
Author(s):  
Anaïs Thibault Landry ◽  
Marylène Gagné ◽  
Jacques Forest ◽  
Sylvie Guerrero ◽  
Michel Séguin ◽  
...  

Abstract. To this day, researchers are debating the adequacy of using financial incentives to bolster performance in work settings. Our goal was to contribute to current understanding by considering the moderating role of distributive justice in the relation between financial incentives, motivation, and performance. Based on self-determination theory, we hypothesized that when bonuses are fairly distributed, using financial incentives makes employees feel more competent and autonomous, which in turn fosters greater autonomous motivation and lower controlled motivation, and better work performance. Results from path analyses in three samples supported our hypotheses, suggesting that the effect of financial incentives is contextual, and that compensation plans using financial incentives and bonuses can be effective when properly managed.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 37-46 ◽  
Author(s):  
PEDRO E.G. LOUREIRO ◽  
SANDRINE DUARTE ◽  
DMITRY V. EVTUGUIN ◽  
M. GRAÇA V.S. CARVALHO

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.


2018 ◽  
Vol 12 (2) ◽  
pp. 60-63
Author(s):  
Mariana Sandu ◽  
Stefan Mantea

Abstract Agri-food systems include branching ramifications, which connect in the upstream the input suppliers with farmers, and downstream farmers, processors, retailers and consumers. In the last decades, at the level of the regions, food systems have undergone rapid transformation as a result of technological progress. The paper analyzes the changes made to the structure, behavior and performance of the agri-food system and the impact on farmers and consumers. Also, the role of agricultural research as a determinant factor of transformation of agri-food system is analyzed. The research objective is to develop technologies that cover the entire food chain (from farm to fork) and meet the specific requirements of consumers (from fork to farm) through scientific solutions in line with the principles of sustainable agriculture and ensuring the safety and food safety of the population.


2019 ◽  
Vol 85 (1(I)) ◽  
pp. 64-71 ◽  
Author(s):  
M. M. Gadenin

The cycle configuration at two-frequency loading regimes depends on the number of parameters including the absolute values of the frequencies and amplitudes of the low-frequency and high-frequency loads added during this mode, the ratio of their frequencies and amplitudes, as well as the phase shift between these harmonic components, the latter having a significant effect only with a small ratio of frequencies. Presence of such two-frequency regimes or service loading conditions for parts of machines and structures schematized by them can significantly reduce their endurance. Using the results of experimental studies of changes in the endurance of a two-frequency loading of specimens of cyclically stable, cyclically softened and cyclically hardened steels under rigid conditions we have shown that decrease in the endurance under the aforementioned conditions depends on the ratio of frequencies and amplitudes of operation low-frequency low-cycle and high-frequency vibration stresses, and, moreover, the higher the level of the ratios of amplitudes and frequencies of those stacked harmonic processes of loading the greater the effect. It is shown that estimation of such a decrease in the endurance compared to a single frequency loading equal in the total stress (strains) amplitudes can be carried out using an exponential expression coupling those endurances through a parameter (reduction factor) containing the ratio of frequencies and amplitudes of operation cyclic loads and characteristic of the material. The reduction is illustrated by a set of calculation-experimental curves on the corresponding diagrams for each of the considered types of materials and compared with the experimental data.


2020 ◽  
Author(s):  
nurul atika

Abstrak- In general, this study aims to determine and analyze the role of supervision in an education. This research uses the literature study method by collecting literature (material materials) sourced from books, journals, and other sources related to the science of Educational Administration. Supervision comes from the word super and vision, which means to see and review from above or view and assess from above, which is carried out by superiors on the activities, creativity and performance of subordinates. In terms of terms, in Carter's Good Dictionary Education, supervision is all the efforts of school officials in leading teachers and other education personnel to improve teaching. These include stimulating, selecting the growth and development of teachers' positions, selecting and revising educational goals, teaching materials and teaching methods, and evaluating teaching. Educational supervision has very important goals and benefits. The scope of educational supervision includes the following: Managerial supervision of the curriculum, Managerial supervision of student affairs, Managerial supervision of educators and education personnel, Managerial supervision of facilities and infrastructure, Managerial supervision of finance, Managerial supervision of public relations, Managerial supervision of administration, Administration supervision academics about learning, related to methods, sourcing strategies, and evaluations.


2020 ◽  
Author(s):  
Małgorzata Kossowska

One might assume that the desire to help (here described as Want) is the essential driver of helping declarations and/or behaviors. However, even if desire to help is low, helping behavior may still occur if the expectancy regarding the perceived effectiveness of helping is high. We tested these predictions in a set of three experimental studies. In all three, we measured the desire to help (Want) and the Expectancy that the aid would be impactful for the victim; in addition, we manipulated Expectancy in Study 3. In Studies 1 and 3, we measured the participants’ declaration to help while in Study 2, their helping behavior was examined. In all three studies, we used variations of the same story about a victim. The results supported our hypothesis. Thus, the studies help to tease apart the determinants of helping behavior under conditions of lowered desire to do so, an issue of great importance in public policymaking.


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