An aging theory‐based mathematic model for estimating the wax content of wax deposits using the Fick's second law

AIChE Journal ◽  
2019 ◽  
Vol 66 (4) ◽  
Author(s):  
Rongbin Li ◽  
Qiyu Huang ◽  
Dongxu Zhang ◽  
Xiangrui Zhu ◽  
Jinxu Shan ◽  
...  
Keyword(s):  
Mathematic Model ◽  
Second Law ◽  
Aging Theory ◽  
Wax Content ◽  
Wax Deposits

scholarly journals TRANSITION AND EVOLUTION OF INFORMATION AT THE MICROSCOPIC LEVEL

T-Comm ◽  
2021 ◽  
Vol 15 (5) ◽  
pp. 62-66
Author(s):  
Aleksey V. Yudenkov ◽  
◽  
Aleksandr M. Volodchenkov ◽  
Liliya P. Rimskaya ◽  
◽  
...  
Keyword(s):  
Information Theory ◽  
Phase Space ◽  
Information Technologies ◽  
Second Law Of Thermodynamics ◽  
Mathematic Model ◽  
Second Law ◽  
Space Model ◽  
Discrete Phase ◽  
Markovian Systems ◽  
Phase Space Model

A simultaneous development of the fundamental research areas of the information theory is needed for efficient development in the information technologies. It is known that for the complicated macroscopic systems information evolution may be shaped on the basis of the principal thermodynamics laws (the second law of thermodynamics, etc). At the same time it is not known whether the fundamentals of the information theory for the macroscopic systems may be applicable to the microscopic systems. The study works out a mathematic model of the discrete phase space adapted to describing the evolution of information (entropy) of the microscopic systems. The discrete phase-space model rests on the indeterminacy principle and fundamental properties of the discrete continuous-time Markovian systems. The Kolmogorov equations represent the main mathematical tools technique. The suggested model refers to the smallest metric scale when the external macroscopic observation is possible. This scale can be viewed as a quasiclassical level. The research results are the following. The structure of the phase space of the elementary signal is revealed. It is demonstrated that the entropy of the microscopic systems increases, i.e. for the microscopic systems the second law of thermodynamics is true. There has been demonstrated transition from the microscopic model to the macroscopic one thus proving the former’s adequacy. The discrete phase-space model is promising in the aspect of further development. For example, it can be applied to the physical systems “particle – field”. The approach represented by the model will allow to study electromagnetic and gravity fields at the quasiclassical level. The above model of the discrete phase space and its application in the study of the evolution of the microscopic systems is a proprietary design of the authors.

Experimental Investigation of the Difference in Wax Deposition Aging Rate Between Polyethylene and Steel Pipes

2020 ◽  
Author(s):  
Rongbin Li ◽  
Yaping Li ◽  
Danfu Cao ◽  
Junfang Wang ◽  
Xin Liu
Keyword(s):  
Operating Conditions ◽  
Wax Deposition ◽  
Flow Loop ◽  
Waxy Crude Oil ◽  
Scanning Calorimetry ◽  
Aging Rate ◽  
Wax Content ◽  
The Difference ◽  
Dsc Method ◽  
Wax Deposits

Abstract Wax deposition is an intrinsic problem existing in the production and transportation of waxy crude oil. In the oilfield, non-metallic pipe especially high-density polyethylene pipe (HDPE) has been widely used to solve corrosion problems due to its excellent performance in intensity and corrosion. However, the wax deposition problem in polyethylene (PE) pipe has never been evaluated using dynamic and systemic apparatus. Only a few studies focus on the wax deposition on the coated polyethylene surface by using the cold finger apparatus in recent decades. In this study, the wax deposition experiments were performed using an in-door flow-loop with detachable PE and stainless steel (SS) test sections under the laminar flow regime at the same time to investigate the difference in wax deposition aging rate between the PE and SS pipes. The wax deposits under different operating conditions in both PE and SS pipes were sampled by three layers to study the aging rate at different radial locations during the wax deposition. The wax precipitation characteristics of the wax deposits were determined by using the differential scanning calorimetry (DSC) method. It was found that the wax contents of the wax deposits in PE pipe were lower than that in the SS pipe. And the difference of the wax content between PE pipe and SS pipe decreases with the depositing duration. Eventually, the wax contents of the wax deposits in PE pipe were almost the same as that in the SS pipe. The heat conduction and heat transfer processes in PE pipe and SS pipe were analyzed. The thermal gradient and the concentration gradient at wall were calculated and combined with the heat and mass transfer of wax during the wax deposition to illustrate the difference in wax content. It was found that the variations of the thermal and concentration gradients have significant effects on the diffusion process of wax molecules within the wax deposit layer and thus changing the aging rate. The comparisons and findings of wax deposition between the two kinds of pipes have provided a significant reference for the application of non-metallic pipe in the oilfield.

Experimental Study on Wax Removal With Real Wax Deposits

2018 ◽  
Author(s):  
Weidong Li ◽  
Qiyu Huang ◽  
Xue Dong ◽  
Xuedong Gao ◽  
Lei Hou
Keyword(s):  
Test Section ◽  
Wax Deposition ◽  
Flow Loop ◽  
Gravity Settling ◽  
Experimental Apparatus ◽  
Field Practice ◽  
Force Profile ◽  
Wax Content ◽  
Wax Deposits ◽  
Wax Removal

Pipeline pigging is one of the most widely used wax remediation techniques in field practice. However, it still depends heavily on “rule-of-thumb” due to the limited understanding of wax deposit properties and wax removal mechanisms. By far, laboratory studies on pipeline pigging generally suffer a gross defect in test materials, i.e., the big discrepancy between the experimental wax samples and real wax deposits. To this end, this paper aims to explore the wax removal in pigging with naturally deposited wax, using a self-designed experimental facility. Wax deposit mass and wax content, two decisive indexes affecting wax removal, were also investigated. The experimental apparatus consists of two parts: a flow loop equipped with a detachable test section to achieve real wax deposits and a wax removal apparatus to perform pigging operations. The test section can be conveniently detached from the flow loop and/or mounted onto the wax removal apparatus for a quick conversion between wax deposition and pigging operation. The results indicate that a higher bulk flow temperature decreases the wax deposit mass and increases the wax content of deposit. Additionally, the distributions of wax content and wax layer thickness suggest that gravity settling plays no role in wax deposition. Moreover, the wax resistive force profile of naturally deposited wax presents four distinct stages, i.e., the build-up phase, the pre-plug phase, the plug phase and the production phase. To the best of the authors’ knowledge, this is the first study on wax removal with real wax deposits. It paves the way for the application of previous artificial-wax-based researches to real wax deposit scenarios.

Investigation of thickness and wax content of wax deposits in polyethylene pipe using a flow loop

AIChE Journal ◽  
2020 ◽  
Vol 67 (1) ◽  
Author(s):  
Rongbin Li ◽  
Qiyu Huang ◽  
Dongxu Zhang ◽  
Xiangrui Zhu ◽  
Jinxu Shan ◽  
...  
Keyword(s):  
Flow Loop ◽  
Polyethylene Pipe ◽  
Wax Content ◽  
Wax Deposits

Quality caracterisation of propolis tinctures by pharmacopoeial parameters and wax content

Planta Medica ◽  
2006 ◽  
Vol 72 (11) ◽  
Author(s):  
J Cvek ◽  
S Zubčic ◽  
D Vitali ◽  
I Vedrina-Dragojevic ◽  
S Tomic ◽  
...  
Keyword(s):  
Wax Content

Quality caracterisation of propolis tinctures by pharmacopoeial parameters and wax content

Planta Medica ◽  
2006 ◽  
Vol 72 (11) ◽  
Author(s):  
J Cvek ◽  
S Zubčic ◽  
D Vitali ◽  
I Vedrina-Dragojevic ◽  
S Tomic ◽  
...  
Keyword(s):  
Wax Content

Effect of Rainfall Exposure on Leaf Wettability in Near-Isogenic Barley Lines with Different Leaf Wax Content.

1998 ◽  
Vol 54 (2) ◽  
pp. 155-160 ◽  
Author(s):  
Shigemi TANAKAMARU ◽  
Toshihiko TAKEHANA ◽  
Kazuyoshi KIMURA
Keyword(s):  
Leaf Wax ◽  
Wax Content ◽  
Leaf Wettability
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