Thickness Investigation and Prevention Strategy of Hydrate Deposition During Avoidance Typhoon for Deep Water Gas Well

2021 ◽  
Author(s):  
Shikun Tong ◽  
Zhiyuan Wang ◽  
Jianbo Zhang ◽  
Zhangrui Chen ◽  
Yingchao Li ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Management Program ◽  
Prevention Strategy ◽  
Gas Wells ◽  
Gas Well ◽  
Hydrate Deposition ◽  
Induced Flow ◽  
The Cost ◽  
Intrinsic Kinetic ◽  
Water Gas

Abstract The investigation of hydrate deposition is a significant basis for the hydrate prevention strategy during avoidance typhoons for deepwater gas wells. Shut-in operation is a necessary procedure due to avoidance typhoon, the hydrate intrinsic kinetic potential increases the growth rate under shut-in conditions. We establish the model of hydrate thickness investigation and the simulations illustrate that the hydrate thickness layer is relatively minor during avoidance typhoon. Meanwhile, hydrate is aggravated by the environment of low temperature and strong disturbance near the mud line due to production after avoidance typhoon. We discuss the variation of temperature profile and concentration of ethylene glycol during restart operation. The concentration variation of the ethylene glycol on the induced flow show after restart operation that the hydrate inhibitor satisfies the hydrate prevention requirements. This research provides a significant design for the hydrate management program during avoidance typhoon for deepwater gas wells, which is useful to the development of traditional avoidance strategy and decreased the cost of hydrate inhibitors.

Hydrate deposition prediction model for deep-water gas wells under shut-in conditions

Fuel ◽  
2020 ◽  
Vol 275 ◽  
pp. 117944 ◽  
Author(s):  
Zhiyuan Wang ◽  
Shikun Tong ◽  
Chao Wang ◽  
Jianbo Zhang ◽  
Weiqi Fu ◽  
...  
Keyword(s):  
Prediction Model ◽  
Deep Water ◽  
Gas Wells ◽  
Hydrate Deposition ◽  
Water Gas

Numerical Simulation Study on the Key Influencing Factors of Water-Invasion Performance for the Gas Wells with Bottom-Water

2014 ◽  
Vol 884-885 ◽  
pp. 104-107
Author(s):  
Zhi Jun Li ◽  
Ji Qiang Li ◽  
Wen De Yan
Keyword(s):  
Numerical Simulation ◽  
Influencing Factors ◽  
Bottom Water ◽  
Simulation Method ◽  
Gas Production ◽  
Production Performance ◽  
Gas Wells ◽  
Two Phase ◽  
Gas Well ◽  
Water Gas

For the water-sweeping gas reservoir, especially when the water-body is active, water invasion can play positive roles in maintaining formation pressure and keeping the gas well production. But when the water-cone break through and towards the well bottom, suffers from the influencing of gas-water two phase flows, permeability of gas phase decrease sharply and will have a serious impact on the production performance of the gas well. Moreover, the time when the water-cone breakthrough will directly affect the final recovery of the gas wells, therefore, the numerical simulation method is used to conduct the research on the key influencing factors of water-invasion performance for the gas wells with bottom-water, which is the basis of the mechanical model for the typical gas wells with bottom-water. It indicate that as followings: (1) the key influencing factors of water-invasion performance for the gas wells with bottom-water are those, such as the open degree of the gas beds, well gas production and the amount of Kv/Kh value; and (2) the barrier will be in charge of great significance on the water-controlling for the bottom water gas wells, and its radius is the key factor to affect water-invasion performance for the bottom water gas wells where the barriers exist nearby.

Laboratory Methods for Evaluation Of Inhibitors for Use in Oil and Gas Wells★

CORROSION ◽  
1954 ◽  
Vol 10 (3) ◽  
pp. 103-109 ◽  
Author(s):  
E. C. GRECO ◽  
J. C. SPALDING
Keyword(s):  
Drop Size ◽  
Corrosion Inhibitors ◽  
Oil And Gas ◽  
Size Ratio ◽  
Laboratory Evaluation ◽  
Manufacturing Companies ◽  
Gas Wells ◽  
Gas Well ◽  
Chemical Manufacturing ◽  
The Cost

Abstract The need for a compilation of methods for laboratory evaluation of oil and gas well corrosion inhibitors was recognized at the national meeting of the NACE in 1952. At that time, the chairman of TP-1 appointed the authors as a committee to contact those companies, both producing and chemical manufacturing companies, known to be interested in the problem of oil and gas well inhibitors. Subsequently, inquiries were sent to all major producing companies that were members of NACE, and several of the chemical manufacturing companies that were known to be working on the development of oil and gas well corrosion inhibitors. As a result, methods used by some ten major producing companies and four chemical manufacturing companies along with methods used in one of the research departments of a university were gathered. The general classification of tests used in the laboratory are presented along with some meager information as to the correlation of such tests with field experience. The short range purpose of this article is to present to all interested in the problem the possible methods that may be used in the laboratory for such evaluation work and at the same time to solicit from all those receiving this report information that may lead TP-1 to the adoption of or, at least, recommendation of standardized laboratory procedure. The latter action, of course, is the long range purpose of this work. Data gathered from companies canvassed indicate the majority working in this field still rely upon corroding systems as set up in the laboratory (whether reflecting field conditions or entirely synthetic) to produce weight loss upon coupons made from material expected to be used in the field. In addition, there are a few companies working on such varied methods of laboratory evaluation as the determination of: 1. film resistivity; 2. hydrogen evolution; 3. drop size ratio, etc. One discusser deals with static tests and sessile drop tests. He points to several theoretical and practical objections to the drop test, asserting that the drop test is unreliable because wettability criteria cannot be translated always into inhibitor efficiencies. The question of interfacial tensions between metals and fluids is considered with the conclusion that the distinction between adsorptive and oil wetting inhibitors is not clear. The discusser does not believe that contact angle measurements can be used theoretically to predict the extent of oil or water wetting of a surface or that it can be assumed that oil-wet surfaces will not corrode. A second discusser outlines the methods used by one company in determining the efficiency and economics of inhibitors. The principal objection the discusser has to the committee's aim is that the number of variables in producing well systems are so great that laboratory tests cannot be considered conclusive until backed by field experience. Tests with wetting agents are described in which the rate of adsorption of water dispersable inhibitors may be checked. The discusser also says that the effectiveness of an inhibitor should be measured by the cost of well equipment that must be replaced, pointing out by examples several instances when the cost of equipment replaced was materially reduced as a result of the use of an inhibitor. He concludes selection of inhibitors by the drop-size ratio or oil-wetting tests is reliable for oil and gas wells but not for gas condensate wells. Speed of the drop size ratio method and the possibility of quantitative recommendations are assets also. This factor is important as indicated by a study which showed a range of inhibitor costs per barrel from $0.009 to $0.224.

Application of Ejector Technology to the Efficient Exploitation in the Low-Pressure Gas Well

2013 ◽  
Vol 433-435 ◽  
pp. 2196-2202
Author(s):  
Xue Yuan Long ◽  
Zhi Jun Li ◽  
Yuan Tian
Keyword(s):  
Numerical Simulation ◽  
Design Method ◽  
Field Tests ◽  
Low Pressure ◽  
Structure Design ◽  
Building Structure ◽  
Gas Wells ◽  
Gas Well ◽  
The Cost ◽  
Dynamics Method

According to the research status of spray and drainage technology at home and abroad, based on the basic design of the ejector, this paper designs the ejector geometry, and do numerical simulation and analysis for ejection and combination flow field inside the ejector by using computational fluid dynamics method, building structure design of ejectors with pressure-gain for low-pressure gas wells. Verified by numerical simulation and field tests, the results showed that ejector design method is reliable. The operation of the device at the scene is safe and stable, achieving such goals as using energy from high-pressure wells to drive the low-pressure wells to work stably; delaying pressurization and exploitation for gas wells, reducing the cost of production and management. Field experiment is very effective, providing a new channel for us to increase the pressure of low-pressure gas wells and exploit them.

scholarly journals Economic burden of childhood diarrhea in Burundi

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Fulgence Niyibitegeka ◽  
Arthorn Riewpaiboon ◽  
Sitaporn Youngkong ◽  
Montarat Thavorncharoensap
Keyword(s):  
Economic Burden ◽  
Cost Model ◽  
Primary Treatment ◽  
Management Program ◽  
Community Based ◽  
Factors Affecting ◽  
Hospitalization Costs ◽  
Illness Study ◽  
The Cost ◽  
Substantial Economic Burden

Abstract Background In 2016, diarrhea killed around 7 children aged under 5 years per 1000 live births in Burundi. The objective of this study was to estimate the economic burden associated with diarrhea in Burundi and to examine factors affecting the cost to provide economic evidence useful for the policymaking about clinical management of diarrhea. Methods The study was designed as a prospective cost-of-illness study using an incidence-based approach from the societal perspective. The study included patients aged under 5 years with acute non-bloody diarrhea who visited Buyenzi health center and Prince Regent Charles hospital from November to December 2019. Data were collected through interviews with patients’ caregivers and review of patients’ medical and financial records. Multiple linear regression was performed to identify factors affecting cost, and a cost model was used to generate predictions of various clinical and care management costs. All costs were converted into international dollars for the year 2019. Results One hundred thirty-eight patients with an average age of 14.45 months were included in this study. Twenty-one percent of the total patients included were admitted. The average total cost per episode of diarrhea was Int$109.01. Outpatient visit and hospitalization costs per episode of diarrhea were Int$59.87 and Int$292, respectively. The costs were significantly affected by the health facility type, patient type, health insurance scheme, complications with dehydration, and duration of the episode before consultation. Our model indicates that the prevention of one case of dehydration results in savings of Int$16.81, accounting for approximately 11 times of the primary treatment cost of one case of diarrhea in the community-based management program for diarrhea in Burundi. Conclusion Diarrhea is associated with a substantial economic burden to society. Evidence from this study provides useful information to support health interventions aimed at prevention of diarrhea and dehydration related to diarrhea in Burundi. Appropriate and timely care provided to patients with diarrhea in their communities and primary health centers can significantly reduce the economic burden of diarrhea. Implementing a health policy to provide inexpensive treatment to prevent dehydration can save significant amount of health expenditure.

Assessment of hydrate flow obstacles during the initial restarting period of deep-water gas wells

2021 ◽  
Author(s):  
Weiguo Zhang ◽  
Hao Jin ◽  
Qingjie Du ◽  
Kai Xie ◽  
Binbin Zhang ◽  
...  
Keyword(s):  
Deep Water ◽  
Gas Wells ◽  
Water Gas

Openhole Multistage Completion Evaluation Incorporating Deployment of Downhole Shut-in Tool Application in Sour Carbonate Gas Wells, Field Application

2021 ◽  
Author(s):  
Mauricio Espinosa ◽  
Jairo Leal ◽  
Ron Zbitowsky ◽  
Eduardo Pacheco
Keyword(s):  
Gas Flow ◽  
Operational Risk ◽  
Tool Design ◽  
Lessons Learned ◽  
Differential Pressure ◽  
Gas Wells ◽  
Flow Area ◽  
Gas Well ◽  
Heterogeneous Rocks ◽  
The Impact

Abstract This paper highlights the first successful application of a field deployment of a high-temperature (HT) downhole shut-in tool (DHSIT) in multistage fracturing completions (MSF) producing retrograde gas condensate and from sour carbonate reservoirs. Many gas operators and service providers have made various attempts in the past to evaluate the long-term benefit of MSF completions while deploying DHSIT devices but have achieved only limited success (Ref. 1 and 2). During such deployments, many challenges and difficulties were faced in the attempt to deploy and retrieve those tools as well as to complete sound data interpretation to successfully identify both reservoir, stimulation, and downhole productivity parameters, and especially when having a combination of both heterogeneous rocks having retrograde gas pressure-volume-temperature (PVT) complexities. Therefore, a robust design of a DHSIT was needed to accurately shut-in the well, hold differential pressure, capture downhole pressure transient data, and thereby identify acid fracture design/conductivity, evaluate total KH, reduce wellbore storage effects, properly evaluate transient pressure effects, and then obtain a better understanding of frac geometry, reservoir parameters, and geologic uncertainties. Several aspects were taken into consideration for overcoming those challenges when preparing the DHSIT tool design including but not limited to proper metallurgy selection, enough gas flow area, impact on well drawdown, tool differential pressure, proper elastomer selection, shut-in time programming, internal completion diameter, and battery operation life and temperature. This paper is based on the first successful deployment and retrieval of the DHSIT in a 4-½" MSF sour carbonate gas well. The trial proved that all design considerations were important and took into consideration all well parameters. This project confirmed that DHSIT devices can successfully withstand the challenges of operating in sour carbonate MSF gas wells as well as minimize operational risk. This successful trial demonstrates the value of utilizing the DHSIT, and confirms more tangible values for wellbore conductivity post stimulation. All this was achieved by the proper metallurgy selection, maximizing gas flow area, minimizing the impact on well drawdown, and reducing well shut-in time and deferred gas production. Proper battery selection and elastomer design also enabled the tool to be operated at temperatures as high as 350 °F. The case study includes the detailed analysis of deployment and retrieval lessons learned, and includes equalization procedures, which added to the complexity of the operation. The paper captures all engineering concepts, tool design, setting packer mechanism, deployment procedures, and tool equalization and retrieval along with data evaluation and interpretation. In addition to lessons learned based on the field trial, various recommendations will be presented to minimize operational risk, optimize shut-in time and maximize data quality and interpretation. Utilizing the lessons learned and the developed procedures presented in this paper will allow for the expansion of this technology to different gas well types and formations as well as standardize use to proper evaluate the value of future MSF completions and stimulation designs.

Researches of technological mode of operation of gas wells with a single-lift elevator at a critical speed of upper flow

2021 ◽  
pp. 97-103
Author(s):  
R.A. Gasumov ◽  
◽  
E.R. Gasumov ◽  
Keyword(s):  
Gas Flow ◽  
Operating Conditions ◽  
Physical Parameters ◽  
Gas Wells ◽  
Gas Well ◽  
Field Development ◽  
Mode Of Operation ◽  
Water Drops ◽  
Liquid Flows ◽  
Technological Mode

The article discusses the modes of movement of gas-liquid flows in relation to the operating conditions of waterlogged gas wells at a late stage of field development. Algorithms have been developed for calculating gas well operation modes based on experimental work under conditions that reproduce the actual operating conditions of flooded wells of Cenomanian gas deposits. The concept of calculating the technological mode of operation of gas wells with a single-row elevator according to the critical velocity of the upward flow is considered based on the study of the equilibrium conditions of two oppositely directed forces: the gravity of water drops directed downward and the lifting force moving water drops with a gas flow directed upward. A calculation was made according to the method of the averaged physical parameters of formation water and natural gas in the conditions of flooded Cenomanian gas wells in Western Siberia. The results of a study of the dependence of the critical flow rate of Cenomanian wells on bottomhole pressure and diameter of elevator pipes are presented.

Flow Assurance in Deep-Water Gas Pipelines: Locating Hydrate Plugging Position in a Fast Way

2021 ◽  
Author(s):  
Jing Yu ◽  
Cheng Hui ◽  
Chao Wen Sun ◽  
Zhan Ling Zou ◽  
Bin Lu Zhuo ◽  
...  
Keyword(s):  
Pressure Drop ◽  
Deep Water ◽  
Pipe Wall ◽  
Gas Pipeline ◽  
Flow Assurance ◽  
Gas Pipelines ◽  
Long Distance ◽  
Hydrate Layer ◽  
Hydrate Deposition ◽  
Water Gas

Abstract Hydrate-associated issues are of great significance to the oil and gas sector when advancing the development of offshore reservoir. Gas hydrate is easy to form under the condition featuring depressed temperature and elevated pressure within deep-water gas pipeline. Once hydrate deposition is formed within the pipelines, the energy transmission efficiency will be greatly reduced. An accurate prediction of hydrate-obstruction-development behavior will assist flow-assurance engineers to cultivate resource-conserving and environment-friendly strategies for managing hydrate. Based on the long-distance transportation characteristics of deep-water gas pipeline, a quantitative prediction method is expected to explain the hydrate-obstruction-formation behavior in deep-water gas pipeline throughout the production of deep-water gas well. Through a deep analysis of the features of hydrate shaping and precipitation at various locations inside the system, the advised method can quantitatively foresee the dangerous position and intensity of hydrate obstruction. The time from the start of production to the dramatic change of pressure drop brought about by the deposition of hydrate attached to the pipe wall is defined as the Hydrate Plugging Alarm Window (HPAW), which provides guidance for the subsequent hydrate treatment. Case study of deep-water gas pipeline constructed in the South China Sea is performed with the advised method. The simulation outcomes show that hydrates shape and deposit along pipe wall, constructing an endlessly and inconsistently developing hydrate layer, which restricts the pipe, raises the pressure drop, and ultimately leads to obstruction. At the area of 700m-3200m away from the pipeline inlet, the hydrate layer develops all the more swiftly, which points to the region of high risk of obstruction. As the gas-flow rate increases, the period needed for the system to shape hydrate obstruction becomes less. The narrower the internal diameter of the pipeline is, the more severe risk of hydrate obstruction will occur. The HPAW is 100 days under the case conditions. As the concentration of hydrate inhibitor rises, the region inside the system that tallies with the hydrate phase equilibrium conditions progressively reduces and the hydrate deposition rate slows down. The advised method will support operators to define the location of hydrate inhibitor injection within a shorter period in comparison to the conventional method. This work will deliver key instructions for locating the hydrate plugging position in a fast way in addition to solving the problem of hydrate flow assurance in deep-water gas pipelines at a reduced cost.

Case History: Lessons learned From Retrieval of Coiled Tubing Stuck by Massive Hydrate Plug When Well Testing in an Ultra Deep Water Gas Well in Mexico

2011 ◽  
Author(s):  
Victor Gerardo Vallejo ◽  
Aciel Olivares ◽  
Pablo Crespo Hdez ◽  
Eduardo R. Roman ◽  
Claudio Rogerio Tigre Maia ◽  
...  
Keyword(s):  
Deep Water ◽  
Case History ◽  
Lessons Learned ◽  
Well Testing ◽  
Gas Well ◽  
Coiled Tubing ◽  
Hydrate Plug ◽  
Water Gas
Sign in / Sign up

Export Citation Format

Share Document