scholarly journals Study on mixing interface of continuous large drop and U-shaped product pipeline

2021 ◽  
Vol 300 ◽  
pp. 01005
Author(s):  
Liang Feng ◽  
Huafeng Zhu ◽  
Junjiang Liu ◽  
Tianhao Liao
Keyword(s):  
Tracking Error ◽  
Diesel Oil ◽  
Previous Method ◽  
Mountainous Area ◽  
Large Drop ◽  
Long Distance ◽  
Oil Pipeline ◽  
Operation Control ◽  
Mixed Oil ◽  
Product Pipeline

In the long-distance pipeline of product oil, gasoline and diesel oil are transported in batches. Due to the large difference of physical properties between the two kinds of oil products, there will be oil mixing at each interface. Because the index parameters of mixed oil do not meet the sales standard, it is necessary to track the interface accurately, so as to provide necessary reference for cutting mixed oil. The topography of southwest mountainous area is characterized by continuous large drop and U-shape, which brings difficulties to batch tracking of product oil pipeline. The previous method is not suitable for this type of pipeline. Therefore, it is necessary to re study the batch tracking method of this type of product pipeline, and use vs2019 to write batch tracking software for continuous large drop and U-shaped product pipeline based on this method. The batch tracking error of the software for this type of pipeline is within the acceptable range, which can provide more accurate reference for the operation control personnel

scholarly journals Formation Mechanism of Trailing Oil in Product Oil Pipeline

Processes ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 7 ◽  
Author(s):  
Enbin Liu ◽  
Wensheng Li ◽  
Hongjun Cai ◽  
Shanbi Peng
Keyword(s):  
Formation Mechanism ◽  
Diesel Oil ◽  
Flow Speed ◽  
Oil Pipeline ◽  
Computational Fluid Dynamics Cfd ◽  
The Dead ◽  
Predicted Values ◽  
New Equation ◽  
Mixed Oil

Trailing oil is the tail section of contamination in oil pipelines. It is generated in batch transportation, for which one fluid, such as diesel oil follows another fluid, such as gasoline, and it has an effect on the quality of oil. This paper describes our analysis of the formation mechanism of trailing oil in pipelines and our study of the influence of dead-legs on the formation of trailing oil. We found that the oil replacement rate in a dead-leg is exponentially related to the flow speed, and the length of the dead-leg is exponentially related to the replacement time of the oil. To reduce the amount of mixed oil, the main flow speed should be kept at about 1.6 m/s, and the length of the dead-leg should be less than five times the diameter of the main pipe. In our work, the Reynolds time-averaged method is used to simulate turbulence. To obtain contamination-related experimental data, computational fluid dynamics (CFD) software is used to simulate different flow rates and bypass lengths. MATLAB software was used to perform multi-nonlinear regression for the oil substitution time, the length of the bypass, and the flow speed. We determined an equation for calculating the length of the trailing oil contamination produced by the dead-leg. A modified equation for calculating the length of the contamination was obtained by combining the existing equation for calculating the length of the contamination with new factors based on our work. The amounts of contamination predicted by the new equation is closer to the actual contamination amounts than predicted values from other methods suggested by previous scholars.

scholarly journals An Improved High-Intelligence Method of Gas and Oil Pipeline Prewarning System in Real Soil Environment

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fang Wang ◽  
Jichuan Xing ◽  
Jinxin Li ◽  
Feng Zhao ◽  
Shufeng Zhang
Keyword(s):  
Optical Fiber ◽  
Real Time ◽  
Recognition Accuracy ◽  
Signal Acquisition ◽  
Soil Environment ◽  
Long Distance ◽  
Vibration Signals ◽  
Oil Pipeline ◽  
Time Performance ◽  
High Intelligence

With the development of technology, the total extent of global pipeline transportation is also increased. However, the traditional long-distance optical fiber prewarning system has poor real-time performance and high false alarm rate when recognizing events threatening pipeline safety. The same vibration signal would vary greatly when collected in different soil environments and this problem would reduce the signal recognition accuracy of the prewarning system. In this paper, we studied this effect theoretically and analyzed soil vibration signals under different soil conditions. Then we studied the signal acquisition problem of long-distance gas and oil pipeline prewarning system in real soil environment. Ultimately, an improved high-intelligence method was proposed for optimization. This method is based on the real application environment, which is more suitable for the recognition of optical fiber vibration signals. Through experiments, the method yielded high recognition accuracy of above 95%. The results indicate that the method can significantly improve signal acquisition and recognition and has good adaptability and real-time performance in the real soil environment.

scholarly journals Safety Study on Wax Deposition in Crude Oil Pipeline

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1572
Author(s):  
Bin Yao ◽  
Deyin Zhao ◽  
Zhi Zhang ◽  
Cheng Huang
Keyword(s):  
Crude Oil ◽  
Cloud Point ◽  
Freezing Point ◽  
Development Trend ◽  
Wax Deposition ◽  
Scanning Calorimetry ◽  
Long Distance ◽  
Wax Precipitation ◽  
Oil Pipeline ◽  
Precipitation Characteristics

The Shunbei crude oil pipeline is prepared to use the unheated transportation process to transport waxy crudes. However, the wax formation in the pipeline is unknown. In order to predict the wax deposition of the pipeline, the physical property experiment of Shunbei crude oil was carried out through field sampling. The density, freezing point, hydrocarbon composition, and viscosity–temperature characteristics of crude oil are obtained. The cloud point and wax precipitation characteristics of the crude oil were obtained using the differential scanning calorimetry (DSC) thermal analysis method. Then, the wax deposition rate of the pipeline was predicted by two methods: OLGA software and wax deposition kinetic model. Finally, the optimal pigging cycle of the pipeline was calculated on this basis. The results show that: Shunbei crude oil is a light crude oil with low wax content, a low freezing point, and a high cloud point. Comparing the OLGA simulation results with the calculation results of the Huang Qiyu model, the development trend of wax deposition along the pipeline was the same under different working conditions. The relative error of the maximum wax layer thickness was 6%, proving that it is feasible for OLGA to simulate wax deposition in long-distance crude oil pipelines. Affected by the wax precipitation characteristics of Shunbei crude oil, there was a peak of wax precipitation between the pipeline section where crude oil temperature was 9.31–13.31 °C and the recommended pigging cycle at the lowest throughput was 34 days in winter and 51 days in spring and autumn.

Oil Temperature Prediction of Long-Distance Hot-Crude-Oil Pipeline Based on GA-BP Optimization

2020 ◽  
Author(s):  
Tao Yu ◽  
Peng Dong ◽  
Yang Yu ◽  
Jinzhou Song ◽  
Jie Zhang
Keyword(s):  
Prediction Model ◽  
Crude Oil ◽  
Pour Point ◽  
Theoretical Formula ◽  
Production Data ◽  
Influence Coefficient ◽  
Long Distance ◽  
Temperature Prediction ◽  
Oil Pipeline ◽  
Actual Production

Abstract Due to the high pour point of the oil products transported in the long-distance high wax crude oil pipeline, in order to ensure the operation safety, it is necessary to adopt heating transmission technology, so as to ensure that the oil temperature along the pipeline is 3–5 °C higher than the pour point, that is to say, the oil temperature is the most important operation parameter of the long-distance hot oil pipeline, and the accurate prediction and control of the oil temperature is the premise of the pipeline safety optimization. Aiming at the problems of large prediction error and poor applicability of the previous theoretical formula, this paper studies the establishment of oil temperature prediction model by using data mining algorithms such as Back Propagation (BP) neural network, and improves the prediction efficiency and accuracy of the model by using Genetic Algorithm (GA) optimization. The correlation coefficient formula is used to calculate the influence coefficient of oil temperature, ground temperature, pipeline transportation and other parameters on the inlet oil temperature of the downstream station, so as to obtain the input parameters of the model. The actual production data training model is downloaded through SCADA system, and the prediction accuracy of the control model is ±0.5 °C. Compared with BP model and other theoretical formulas, the accuracy and efficiency of GA-BP oil temperature prediction model are greatly improved, and the adaptability is better. The GA-BP oil temperature prediction model trained according to the actual production data can be effectively applied to the future pipeline big data platform, which lays a theoretical foundation for the intelligent control of the pipeline.

scholarly journals Study on Asymmetry Concentration of Mixed Oil in Products Pipeline

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6398
Author(s):  
Yi Wang ◽  
Baoying Wang ◽  
Yang Liu ◽  
Yongtu Liang
Keyword(s):  
Energy Consumption ◽  
Concentration Curve ◽  
Adsorption Coefficient ◽  
Long Distance ◽  
Estimation Errors ◽  
Mean Velocity ◽  
Adsorption Effect ◽  
The Asymmetry ◽  
Products Pipeline ◽  
Mixed Oil

Long-distance pipelines transporting multiple product oils such as gasoline, diesel and jet fuel, are important facilities for transporting fossil energy. One major concern in operation is the energy consumption of the pipeline. Energy consumption should be made optimized tracking batches of oils and cutting mixed oil, which requires an accurate prediction of concentration curve. In engineering, the concentration curve is usually assumed to be symmetric, but it is actually asymmetric, which may lead to estimation errors. Thus, the asymmetric concentration of mixed oil should be studied. The formation mechanism of the asymmetry of concentration curve has not been clearly clarified. A new method is proposed to measure the asymmetry of the concentration curve. Quantitative analysis is carried out for each factor on the asymmetry distribution of concentration curve. Based on the convection–diffusion equation, a modified oil-mixing model considering near wall adsorption effect is established. The model shows a good agreement with the Jablonski empirical formula. The error, compared with the experimental results, is less than 5%. The main findings are: (1) deviation volume has a negative correlation with pipe diameter and mean velocity; (2) adsorption coefficient has a greater impact on the length ratio of front and tail oil than diffusion coefficient; (3) the influence of all factors considered on the total length of mixed oil, front oil, tail oil and trail oil are basically the same; (4) if the limit of adsorption concentration in adsorption layer is 1, the reasonable value of adsorption coefficient a and b should be around 0.4. The results reveal the mechanism of asymmetric concentration of product oils and can provide practical suggestions to deal with the mixed oil.

Analysis of Hot Oil Pipeline Stress Influencing Factors

2014 ◽  
Vol 887-888 ◽  
pp. 899-902
Author(s):  
Xiao Nan Wu ◽  
Shi Juan Wu ◽  
Hong Fang Lu ◽  
Jie Wan ◽  
Jia Li Liu ◽  
...  
Keyword(s):  
Crude Oil ◽  
High Viscosity ◽  
Analysis Model ◽  
Long Distance ◽  
Oil Pipeline ◽  
Software Analysis ◽  
Key Points ◽  
Temperature And Pressure ◽  
Pressure Changes ◽  
The Impact

In order to reduce the viscosity of crude oil for transport, we often use the way of heating delivery for high pour point, high wax, and high viscosity oil. Crude oil at high temperature, through long-distance transmission, the temperature and pressure changes on the piping stress greater impact. In this paper, in order to explore the main factor of hot oil pipeline stress and the location of key points, we build the XX hot oil pipeline stress analysis model used CAESAR II software, analysis of the impact of changes in temperature and pressure on piping stress when hot oil pipeline running, draw hot oil pipeline stress distribution, clearly identifies the location of key points of stress concentration, and we have come to that temperature is a major factor in generating pipe stress.

The Research of Character of Control Valve on Pipeline

2008 ◽  
Author(s):  
Jing Gong ◽  
Jian Cai
Keyword(s):  
Operating Characteristic ◽  
Control Valve ◽  
Basic Program ◽  
Fluid Viscosity ◽  
Operating Characteristics ◽  
Oil Pipeline ◽  
Actual Operation ◽  
Operation Control ◽  
Coefficient Of Discharge ◽  
The Relationship

Regulating valves are the important components of control system on oil pipeline. The opening of the valves is changed to regulate flow and pressures of pipelines. Operating characteristic of valves is the most important factor influencing the regulating quality, and the distortion is great in actual operation with the variation of working conditions. Beginning with the inherent flow and resistance characteristics of regulating valves, the coefficient of discharge was adjusted considering the influence of fluid viscosity. The relationship between the deformity characteristics of valves and ratio of pressure cut down or turndown ratio was discussed. The system made up by a pump, a valve and a tank was an example to analyze the factors affected the operating characteristic of valves in the actual operation. The influences of different closing valve times, different closing valve laws and different ratio of pressure cut down or turndown ratio on the operating characteristic of valves were analyzed by simulation using Visual Basic program. The results indicated that the operating characteristics of valves were different. And the method of two-stage closing valve was adopted according to the changes of operating characteristic of valves by different closing valve time, different shutting valve laws. The distortion degree of valves in the operation of pipeline was decreased mostly. Then the selection measures of regulating valves were discussed. The factors influencing operating characteristic of valves were analyzed comprehensively. Theory criteria can be provided for selecting regulating valves of pipeline correctly. It is also the key to stable and economically operation control of pipelines.

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