The Impact of Irreducible Water on Stress-Sensitivity of Gas Reservoir Rocks

2012 ◽  
Vol 246-247 ◽  
pp. 472-475
Author(s):  
Hao Xu ◽  
Zhi Ping Li ◽  
Hua Jun Hu

According to many researches, the presence of stress-sensitivity has been confirmed in reservoir rocks. Because it will create huge damage to the permeability of reservoirs, sufficient attention should be made. In this paper, through the experiment, the permeability value change with effective pressure in the condition of saturated with irreducible water and dry environment were compared. The study showed that the stress-sensitivity of core sample was more obvious in the condition of saturated with irreducible water.

2020 ◽  
Vol 213 ◽  
pp. 02001
Author(s):  
Quan Hua Huang ◽  
Hong Jun Ding ◽  
Xing Yu Lin

At present, multiphase flow productivity calculation requires many parameters, and most of them only consider oil and gas two-phase flow, which is complicated and limited. Therefore, a reasonable productivity formula of condensate gas reservoir with producing water is needed. The three-zone model of condensate gas reservoirs is generally applied to the physical model for inferring productivity. On this basis, an improved model is established, which includes that different seepage characteristics are considered for different zones. Moreover, the effects of inclined angle and water production on gas wells are regarded as pseudo-skin factors and additional-skin factors. In addition, Zone I considers the effects of high-speed nonDarcy effect(HSND), starting pressure gradient, stress sensitivity, inclined angle and water production; Zone II is the same way excepting starting pressure gradient and stress sensitivity ; Zone III only considers the effects of inclined angle and water production. As a result, a productivity equation with multiple factors for condensate gas wells is established. Through analysing cases and influences in H gas reservoir X1 well, the HSND, starting pressure gradient, stress sensitivity and water production have a negative impact on gas well productivity, but the inclined angle is opposite. Founded that the starting pressure gradient impacts on productivity is less than the HSND because of the limited radius of Zone I; the impact of the HSND on productivity increases with the decreasing of bottom hole pressure; the impact of water production on gas well productivity is much higher. When the angle is over 60°, the effect of gas


2013 ◽  
Vol 634-638 ◽  
pp. 3577-3581
Author(s):  
Li Li ◽  
Gao Ning Zhou

By measuring the change of confining pressure penetration on sandstone samples of a gas reservoir in Daqing Oil Field, it has been proven that stress sensitivity existed in this gas reservoirs. The measuring results also show that the stress sensitivity levels of mafic is from weak to medium weak due to the better glutinosity and the greater rock hardness. However, some sandstone samples generally do not have stress sensitivity. The impact of stress sensitivity should be thoroughly considered during the development of natural gas, because the existence of cracks which often result in stronger stress sensitivity.


Author(s):  
Mihail Zver'kov

To the article the results of the theoretical and experimental researches are given on questions of estimates of the dynamic rate effect of raindrop impact on soil. The aim of this work was to analyze the current methods to determine the rate of artificial rain pressure on the soil for the assessment of splash erosion. There are the developed author’s method for calculation the pressure of artificial rain on the soil and the assessment of splash erosion. The study aims to the justification of evaluation methods and the obtaining of quantitative characteristics, prevention and elimination of accelerated (anthropogenic) erosion, the creation and the realization of the required erosion control measures. The paper considers the question of determining the pressure of artificial rain on the soil. At the moment of raindrops impact, there is the tension in the soil, which is called vertical effective pressure. It is noted that the impact of rain drops in the soil there are stresses called vertical effective pressure. The equation for calculation of vertical effective pressure is proposed in this study using the known spectrum of raindrops. Effective pressure was 1.4 Pa for the artificial rain by sprinkler machine «Fregat» and 5.9 Pa for long distance sprinkler DD-30. The article deals with a block diagram of the sequence for determining the effective pressure of rain drops on the soil. This diagram was created by the author’s method of calculation of the effective pressure of rain drops on the soil. The need for an integrated approach to the description of the artificial rain impact on the soil is noted. Various parameters characterizing drop erosion are considered. There are data about the mass of splashed soil in the irrigation of various irrigation machinery and installations. For example, the rate (mass) of splashed soil was 0.28…0.78 t/ha under irrigation sprinkler apparatus RACO 4260–55/701C in the conditions of the Ryazan region. The method allows examining the environmental impact of sprinkler techniques for analyzes of the pressure, caused by raindrops, on the soil. It can also be useful in determining the irrigation rate before the runoff for different types of sprinkler equipment and soil conditions.


Diagnosis ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Justin B. Searns ◽  
Manon C. Williams ◽  
Christine E. MacBrayne ◽  
Ann L. Wirtz ◽  
Jan E. Leonard ◽  
...  

AbstractObjectivesFew studies describe the impact of antimicrobial stewardship programs (ASPs) on recognizing and preventing diagnostic errors. Handshake stewardship (HS-ASP) is a novel ASP model that prospectively reviews hospital-wide antimicrobial usage with recommendations made in person to treatment teams. The purpose of this study was to determine if HS-ASP could identify and intervene on potential diagnostic errors for children hospitalized at a quaternary care children’s hospital.MethodsPreviously self-identified “Great Catch” (GC) interventions by the Children’s Hospital Colorado HS-ASP team from 10/2014 through 5/2018 were retrospectively reviewed. Each GC was categorized based on the types of recommendations from HS-ASP, including if any diagnostic recommendations were made to the treatment team. Each GC was independently scored using the “Safer Dx Instrument” to determine presence of diagnostic error based on a previously determined cut-off score of ≤1.50. Interrater reliability for the instrument was measured using a randomized subset of one third of GCs.ResultsDuring the study period, there were 162 GC interventions. Of these, 65 (40%) included diagnostic recommendations by HS-ASP and 19 (12%) had a Safer Dx Score of ≤1.50, (Κ=0.44; moderate agreement). Of those GCs associated with diagnostic errors, the HS-ASP team made a diagnostic recommendation to the primary treatment team 95% of the time.ConclusionsHandshake stewardship has the potential to identify and intervene on diagnostic errors for hospitalized children.


Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 585
Author(s):  
Catalina Iticescu ◽  
Puiu-Lucian Georgescu ◽  
Maxim Arseni ◽  
Adrian Rosu ◽  
Mihaela Timofti ◽  
...  

The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were monitored and optimal solutions for their treatment were suggested so as to allow that the sludge could be used in agriculture according to the characteristics of the soils. The content of heavy metals in the sewage sludge was closely monitored because the use of sewage sludge as a fertilizer does not allow for any increases in the concentrations of these in soils. The article identifies those agricultural areas which are suitable for the use of sludge, as well as ways of correcting some parameters (e.g., pH), which allow the improvement of soil quality and obtained higher agricultural production.


2021 ◽  
Vol 11 (14) ◽  
pp. 6537
Author(s):  
Marian Łupieżowiec

The article presents the concept of monitoring buildings and infrastructure elements located near large construction investments (the construction of high-rise buildings of the Oak Terraces housing estate in Katowice and the construction of a tunnel under the roundabout in Katowice along the intercity express road DTŚ). The impacts include deep excavation, lowering of the groundwater level over a large area, and dynamic influences related to the use of impact methods of soil improvement. The presented monitoring includes observation of the groundwater level with the use of piezometers, geodetic measurements of settlement and inclinations, as well as the measurement of vibration amplitudes generated during the works involving shocks and vibrations. It was also important to observe the development of cracks on the basis of a previously made inventory of damage. The results of the monitoring allow corrections to be made in the technology of works (e.g., reduction of vibration amplitudes, application of additional protections at excavations, etc.) or the use additional safety measures. Currently, there are also monitoring systems used during the operation of completed facilities.


2019 ◽  
Vol 24 (2) ◽  
pp. 199-217 ◽  
Author(s):  
Boy Lüthje

The article examines the development of advanced digital manufacturing (as outlined in the ‘Made-in-China 2025’ government plan) from the perspective of the changing socio-technical paradigms of production. The analysis focuses on the transformations of value chains and work, based on theories of social shaping of technology, regulation theory and regimes of production. Analytically, the author proposes to distinguish between ‘production-driven’ and ‘distribution-driven’ pathways of manufacturing digitalisation. The transformation of semi-rural industrial areas (‘Taobao villages’, named after China’s largest e-commerce platform Taobao) into mass production clusters for e-commerce is depicted as a paradigmatic model of distribution-driven transformation and as a characteristic Chinese strategy in this field. The article examines the impact on industry supply chains and work, leading to ever-more precarious conditions of employment. Policy recommendations focus on local strategies to stabilise supply chain structures and working conditions, as an alternative to the present top-down approaches to manufacturing modernisation in China.


2002 ◽  
Vol 283 (5) ◽  
pp. F861-F875 ◽  
Author(s):  
Saulo Klahr ◽  
Jeremiah Morrissey

Interstitial fibrosis has a major role in the progression of renal diseases. Several animal models are available for the study of renal fibrosis. The models of aminonucleoside-induced nephrotic syndrome, cyclosporin nephrotoxicity, and passive Heyman nephritis are characterized by molecular and cellular events similar to those that occur in obstructive nephropathy. Additionally, inhibition of angiotensin-converting enzyme exerts salutary effects on the progression of renal fibrosis in obstructive nephropathy. Unilateral ureteral obstruction (UUO) has emerged as an important model for the study of the mechanisms of renal fibrosis and also for the evaluation of the impact of potential therapeutic approaches to ameliorate renal disease. Many quantifiable pathophysiological events occur over the span of 1 wk of UUO, making this an attractive model for study. This paper reviews some of the ongoing studies that utilized a rodent model of UUO. Some of the findings of the animal model have been compared with observations made in patients with obstructive nephropathy. Most of the evidence suggests that the rodent model of UUO is reflective of human renal disease processes.


1991 ◽  
Vol 85 (3) ◽  
pp. 905-920 ◽  
Author(s):  
Harold D. Clarke ◽  
Nitish Dutt

During the past two decades a four-item battery administered in biannual Euro-Barometer surveys has been used to measure changing value priorities in Western European countries. We provide evidence that the measure is seriously flawed. Pooled cross-sectional time series analyses for the 1976–86 period reveal that the Euro-Barometer postmaterialist-materialist value index and two of its components are very sensitive to short-term changes in economic conditions, and that the failure to include a statement about unemployment in the four-item values battery accounts for much of the apparent growth of postmaterialist values in several countries after 1980. The aggregate-level findings are buttressed by analyses of panel data from three countries.


Sign in / Sign up

Export Citation Format

Share Document