Study on Natural Gas Drag Reduction Agent and Mechanism of Gas Pipelines Drag Reduction

2008 ◽  
Author(s):  
Guoping Li ◽  
Zhiheng Zhang ◽  
Bing Liu ◽  
Chunman Li ◽  
Weichun Chang ◽  
...  
Keyword(s):  
Natural Gas ◽  
Drag Reduction ◽  
Reduction Method ◽  
Radial Pulsation ◽  
Gas Pipelines ◽  
Oil Pipelines ◽  
Oil Flow ◽  
Pipeline Wall ◽  
Gas Drag ◽  
Long Chain

On the basis of the study on the principle of oil flow and that on mechanism of drag reduction and transportation promotion of oil pipelines, the article makes a further research on the Mechanism of Drag Reduction in the gas pipelines. It points out that the basic cause for gas pipelines drag reduction is to control effectively the radial pulsation of gas adjacent to pipeline wall. It is considered that the most effective drag reduction method is to reduce the pipeline wall’s roughness degree and pipeline wall’s undercoat and to make gas drag reduction agent adjacent to pipeline wall. The research shows that gas drag reduction agent should be a polymer and compound with polarity and nonpolarity long chain.

Synthesis, Performance Evaluation and Field Application of Polymer-Type Natural Gas Drag Reduction Agent

2012 ◽  
Author(s):  
Haihong Xu ◽  
Yanqing Gao ◽  
Guoping Li ◽  
Zhiheng Zhang ◽  
Weichun Chang
Keyword(s):  
Natural Gas ◽  
Drag Reduction ◽  
Radial Pulsation ◽  
Polar Group ◽  
Gas Pipelines ◽  
Natural Gas Pipelines ◽  
Increase Rate ◽  
Gas Drag ◽  
Polymer Type ◽  
Long Chain

Natural gas is gaining popularity in the world as a high quality, clean burning alternative to oil and coal. The Mechanism of Drag Reduction in the natural gas pipelines is to control the radial pulsation of gas adjacent to pipeline wall effectively. The way to lower the pulsation intension of the gas in the thin layer along the wall is to use gas drag reduction agents, whose polar end absorbs fixedly to the surface and whose non-polar long chain suspends in natural gas so as to have a function of restraining the gas’ radial pulsation. The drag reduction agent molecule absorbed to the protruding is mainly to weaken the gas pulsation producing by virtue of roughness degree. The drag reduction agent molecule absorbed to and collected in the dents also has the function of lowering the equivalent roughness degree of the wall surface. A polymer-type natural gas drag reduction agent with polarity as well as nonpolarity long chain was studied. We synthesized polymers that contain long chain fatty acid (F) or long chain ester (E) as soft chain, and alkoxy residues or acylations as polar group, then studied the effects of this polymer-type gas drag reduction agent on the pipe wall, natural gas quality, station processes and equipments as well as post-processing. A test loop with control software was developed for evaluating natural gas drag reduction agents. An on-line injected system for natural gas reduction agent was established. The product was applied on natural gas pipelines in China. In No.1 oil production plant of Changqing oilfield, the drag reducing efficiency is 19.5%, and the flow increase rate is 12.4%. In pipeline from Lanzhou to Yinchuan, the drag reducing efficiency is all above 10%, and the flow increase rate is all above 5%.

scholarly journals Experimental Study on Thermal Insulation Effect of the Buried Oil-Gas Pipelines in Permafrost Regions

Geofluids ◽  
2022 ◽  
Vol 2022 ◽  
pp. 1-19
Author(s):  
Deren Liu ◽  
Jiale Yang ◽  
Xu Wang ◽  
Junming Zhao ◽  
Shuochang Xu ◽  
...  
Keyword(s):  
Natural Gas ◽  
Thermal Insulation ◽  
Vertical Displacement ◽  
Positive Temperature ◽  
Gas Pipelines ◽  
Insulation Layer ◽  
Buried Pipelines ◽  
Pipeline Wall ◽  
Oil Gas ◽  
Permafrost Regions

In permafrost regions, long distance buried pipelines are widely used to transport oil and natural gas resources. However, pipeline problems occur frequently due to the complicated surrounding environment and transportation requirement of positive temperature. In this study, a thermal insulation layer was applied to mitigate permafrost degeneration around the buried oil-gas pipelines. Based on engineering background of the Sebei-Xining-Lanzhou natural gas pipeline in China, an indoor model test was designed and carried out in which many key indices, such as the temperature regime, vertical displacement, pipeline wall stress, and water content, were closely monitored. The test results indicate that the large heat loss of the buried pipeline produces a rapid increase in ground temperatures which seriously reduces the bearing capacity of the permafrost foundation. The buried oil-gas pipelines with a thermal insulation layer can effectively reduce the thawing range and vertical displacement of the permafrost foundation around the buried pipelines, so as to control the stress of the pipeline wall in the normal range and protect the safe and stable operation of the buried oil-gas pipelines. The experimental results can serve as a reference for the construction, operation, and maintenance of buried oil-gas pipelines in permafrost regions.

Experimental Research on the Drag Reduction Mechanism of Natural Gas Drag Reduction Agent and Its Industrial Field Test

2014 ◽  
Vol 53 (31) ◽  
pp. 12494-12501 ◽  
Author(s):  
Zhiqiang Huang ◽  
Zhen Chen ◽  
Qin Li ◽  
Ronggai Zhu ◽  
Shuang Jing ◽  
...  
Keyword(s):  
Natural Gas ◽  
Drag Reduction ◽  
Field Test ◽  
Experimental Research ◽  
Reduction Mechanism ◽  
Gas Drag

Drag Reduction and Velocity Profiles Distribution of Crude Oil Flow in Spiral Pipes

2015 ◽  
Vol 9 (1) ◽  
pp. 1 ◽  
Author(s):  
Yanuar Yanuar ◽  
Kurniawan T. Waskito ◽  
Gunawan Gunawan ◽  
Budiarso Budiarso
Keyword(s):  
Drag Reduction ◽  
Crude Oil ◽  
Velocity Profiles ◽  
Oil Flow

scholarly journals Role of Shearing Dispersion and Stripping in Wax Deposition in Crude Oil Pipelines

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4325
Author(s):  
Zhihua Wang ◽  
Yunfei Xu ◽  
Yi Zhao ◽  
Zhimin Li ◽  
Yang Liu ◽  
...  
Keyword(s):  
Crude Oil ◽  
Flow Rate ◽  
Critical Flow ◽  
Wax Deposition ◽  
Dominant Effect ◽  
Critical Flow Rate ◽  
Oil Pipelines ◽  
Oil Flow ◽  
Shearing Mechanism

Wax deposition during crude oil transmission can cause a series of negative effects and lead to problems associated with pipeline safety. A considerable number of previous works have investigated the wax deposition mechanism, inhibition technology, and remediation methods. However, studies on the shearing mechanism of wax deposition have focused largely on the characterization of this phenomena. The role of the shearing mechanism on wax deposition has not been completely clarified. This mechanism can be divided into the shearing dispersion effect caused by radial migration of wax particles and the shearing stripping effect caused by hydrodynamic scouring. From the perspective of energy analysis, a novel wax deposition model was proposed that considered the flow parameters of waxy crude oil in pipelines instead of its rheological parameters. Considering the two effects of shearing dispersion and shearing stripping coexist, with either one of them being the dominant mechanism, a shearing dispersion flux model and a shearing stripping model were established. Furthermore, a quantitative method to distinguish between the roles of shearing dispersion and shearing stripping in wax deposition was developed. The results indicated that the shearing mechanism can contribute an average of approximately 10% and a maximum of nearly 30% to the wax deposition process. With an increase in the oil flow rate, the effect of the shearing mechanism on wax deposition is enhanced, and its contribution was demonstrated to be negative; shear stripping was observed to be the dominant mechanism. A critical flow rate was observed when the dominant effect changes. When the oil flow rate is lower than the critical flow rate, the shearing dispersion effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. When the oil flow rate is higher than the critical flow rate, the shearing stripping effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. This understanding can be used to design operational parameters of the actual crude oil pipelines and address the potential flow assurance problems. The results of this study are of great significance for understanding the wax deposition theory of crude oil and accelerating the development of petroleum industry pipelines.

Validation of EMAT ILI for Management of Stress Corrosion Cracking in Natural Gas Pipelines

2014 ◽  
Author(s):  
Toby Fore ◽  
Stefan Klein ◽  
Chris Yoxall ◽  
Stan Cone
Keyword(s):  
High Resolution ◽  
Natural Gas ◽  
Stress Corrosion ◽  
Stress Corrosion Cracking ◽  
Corrosion Cracking ◽  
Probability Of Detection ◽  
Gas Pipelines ◽  
Line Pipe ◽  
Natural Gas Pipelines ◽  
Electro Magnetic

Managing the threat of Stress Corrosion Cracking (SCC) in natural gas pipelines continues to be an area of focus for many operating companies with potentially susceptible pipelines. This paper describes the validation process of the high-resolution Electro-Magnetic Acoustical Transducer (EMAT) In-Line Inspection (ILI) technology for detection of SCC prior to scheduled pressure tests of inspected line pipe valve sections. The validation of the EMAT technology covered the application of high-resolution EMAT ILI and determining the Probability Of Detection (POD) and Identification (POI). The ILI verification process is in accordance to a API 1163 Level 3 validation. It is described in detail for 30″ and 36″ pipeline segments. Both segments are known to have an SCC history. Correlation of EMAT ILI calls to manual non-destructive measurements and destructively tested SCC samples lead to a comprehensive understanding of the capabilities of the EMAT technology and the associated process for managing the SCC threat. Based on the data gathered, the dimensional tool tolerances in terms of length and depth are derived.

Sign in / Sign up

Export Citation Format

Share Document