Research on Preheating Temperature Field Test of Natural Gas Pipeline in Service Welding under Extreme Condition

When the natural gas pipeline is welding in service, the fast flowing medium with pressure in the pipe will take away a lot of heat, and the preheating temperature is not easy to be guaranteed, so it is easy to appear hydrogen-induced crack. In this paper, the in-service welding preheating temperature field of natural gas pipeline under the limit condition of unreduced volume was studied, and the pre-welding preheating test was carried out by using the medium frequency heating method. It is found that the temperature below the heating belt increases gradually with the increase of the intermediate frequency heating power, and the fitting shows a quadratic polynomial gradient. There are differences in preheating temperatures on the same circumference. The highest temperature mostly appears in the direction of 3 point of the pipeline, while the lowest temperature mostly appears in the direction of 0 point, which is related to the tightness of the heating belt, sunshine, blowing and other factors. In addition, the preheating temperature field of the pipeline in service is related to the gas flow in the pipeline. At the same heating power, the downstream temperature of the heating belt is higher than the upstream temperature at the same location, and the closer to the heating belt, the higher the temperature is. When the gas flow rate reaches 9.37m/s and the heating power is 160kW, the average measured temperature at 50mm upstream and downstream of the heating belt of Φ1016 pipeline is 107℃, and the average measured temperature at 50mm upstream of the heating belt is 71℃. When the gas flow rate reaches 8.91m/s and the heating power is 200kW, the average measured temperature at the downstream 50mm of the heating belt of Φ1219 pipeline is 72℃, the average measured temperature at the upstream 50mm of the heating belt is 52℃and the average measured temperature at the upstream 30mm of the heating belt is 71℃..

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Electric Heating Power Optimization of Natural Gas Pipeline

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.135-136.516 ◽

2011 ◽

Vol 135-136 ◽

pp. 516-521

Author(s):

Chun Liang Zhang

Keyword(s):

Heat Transfer ◽

Natural Gas ◽

Gas Flow ◽

Electric Heating ◽

Gas Pipeline ◽

Heating Power ◽

Analysis Model ◽

Flow Energy ◽

Heating Cable ◽

Transfer Thermodynamics

After the analysis of gas flow, energy consumption is mainly in the process of heating gas pipeline and natural gas throttle. For this problem, this paper, heat transfer, thermodynamics, computational fluid dynamics are used, the pipeline throttling, convection of natural gas in the pipe and the heat transfer between the gas, wall panels, heating cable, insulation, soil and the atmosphere are all considered, thermal analysis model between the wellhead and the gas gathering station is established, the electric heating power on the gas pipeline is optimized, the optimal electric heating power can be calculated when the temperature of wellhead and gas gathering station is expected to reach are known. The effect of tube diameter, gas volume, surface temperature on the heating power is analyzed.

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Numerical Simulation of Natural Gas Pipeline Transients

Journal of Energy Resources Technology ◽

10.1115/1.4043436 ◽

2019 ◽

Vol 141 (10) ◽

Cited By ~ 3

Author(s):

Abdoalmonaim S. M. Alghlam ◽

Vladimir D. Stevanovic ◽

Elmukhtar A. Elgazdori ◽

Milos Banjac

Keyword(s):

Natural Gas ◽

Gas Flow ◽

Computer Code ◽

Gas Pipeline ◽

Operating Conditions ◽

Transient Effects ◽

Natural Gas Pipeline ◽

Transmission Pipeline ◽

Variable Consumption ◽

Isothermal Gas

Simulations of natural gas pipeline transients provide an insight into a pipeline capacity to deliver gas to consumers or to accumulate gas from source wells during various abnormal conditions and under variable consumption rates. This information is used for the control of gas pressure and for planning repairs in a timely manner. Therefore, a numerical model and a computer code have been developed for the simulation of natural gas transients in pipelines. The developed approach is validated by simulations of test cases from the open literature. Detailed analyses of both slow and fast gas flow transients are presented. Afterward, the code is applied to the simulation of transients in a long natural gas transmission pipeline. The simulated scenarios cover common operating conditions and abrupt disturbances. The simulations of the abnormal conditions show a significant accumulation capacity and inertia of the gas within the pipeline, which enables gas packing and consumers supply during the day time period. Since the numerical results are obtained under isothermal gas transient conditions, an analytical method for the evaluation of the difference between isothermal and nonisothermal predictions is derived. It is concluded that the nonisothermal transient effects can be neglected in engineering predictions of natural gas packing in long pipelines during several hours. The prescribed isothermal temperature should be a few degrees higher than the soil temperature due to the heat generation by friction on the pipelines wall and heat transfer from the gas to the surrounding soil.

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Managing the Pressure to Increase the H2 Capacity Through a Natural Gas Transmission Network

Volume 9: Oil and Gas Applications; Organic Rankine Cycle Power Systems; Steam Turbine ◽

10.1115/gt2020-14043 ◽

2020 ◽

Author(s):

Francis Bainier ◽

Rainer Kurz ◽

Philippe Bass

Keyword(s):

Natural Gas ◽

Partial Pressure ◽

Gas Flow ◽

Network Capacity ◽

Hydrogen Gas ◽

Gas Pipeline ◽

Pipeline Network ◽

Gas Network ◽

Natural Gas Pipeline ◽

Partial Pressures

Abstract Gas Transmission System Operators (TSO1) are considering injecting hydrogen gas into their networks. Blending hydrogen into the existing natural gas pipeline network appears to be a strategy for storing and delivering renewable energy to markets [1], [2], [3]. In the paper GT2019-90348 [4], the authors have explored the efficiency of H2-blending in a natural gas pipeline network. The conclusion of the paper is: the energy transmission capacity and the efficiency decrease with the introduction of H2, nevertheless, the authors conclude that it is not an obstacle, but the way of using transmission natural gas networks should be closely studied to find an economic optimum, based both on capital and operating expenses. To establish the comparison, the paper did not take into account the limits of the equipment; all equipment was considered as compatible with any load of hydrogen blending. In the current paper, the idea is to consider the hypothesis that the only factor which has impact on the infrastructure is the partial pressure of H2. The idea is not new, in 1802, Dalton published a law called Dalton’s Law of Partial Pressures [5]. Dalton established empirically that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual component gases. The partial pressure is the pressure that each gas would exert when it alone occupied the volume of the mixture at the same temperature. Independent of the limits of the equipment, the authors explore the relationships between a network capacity and its associated pressures in regards to the H2 partial pressure. Within the partial pressure constraint, the goal is to find the maximum H2 flowrate. This flowrate is then compared with a flowrate which is a function of % H2. Nevertheless, steel is subjected to hydrogen invasion while being exposed to hydrogen containing environments during mechanical loading: resulting in hydrogen embrittlement (HE). HE also depends on the textured microstructure. In the final results [6] [7], the measured fatigue data reveals that the fatigue life of steel pipeline is degraded by the added hydrogen. The H2 has an effect on the steel fatigue which is not simply due to the partial pressure. The idea of the authors through the results of their 2 papers is to give the key points to help to find the optimum points for introducing H2 into a natural gas network, because, for them, the idea is that partial pressure is a factor in the equilibrium between H2 capacity and the remaining lifetime of the equipment. This paper shows the interest of the pressure management. With this management, it is possible to reach a constant H2 injection flow independently of the natural gas flow in the pipeline. In conclusion, to optimize the H2 capacity in their current network, a proposal to the TSOs is to adjust their dispatching methodology and their Pipeline Integrity Management (PIM) [8] [9].

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SCIENTIFIC AND ENGINEERING PRINCIPLES OF EFFICIENT FUEL USE AND ENVIRONMENTALLY FRIENDLY GAS COMBUSTION IN STOVE PLATES. PART 1. MODERN STATE-OF-THE-ART AND DIRECTIONS FOR IMPROVEMENT THE GAS BURNING IN DOMESTIC GAS COOKERS

Energy Technologies & Resource Saving ◽

10.33070/etars.3.2017.01 ◽

2017 ◽

pp. 3-18 ◽

Cited By ~ 1

Author(s):

B.S. Soroka ◽

V.V. Horupa

Keyword(s):

Natural Gas ◽

Flow Rate ◽

Gas Flow ◽

Renewable Energy Sources ◽

Combustion Process ◽

Orifice Diameter ◽

Firing Process ◽

Gas Flow Rate ◽

Gas Combustion ◽

Gas Stoves

Natural gas NG consumption in industry and energy of Ukraine, in recent years falls down as a result of the crisis in the country’s economy, to a certain extent due to the introduction of renewable energy sources along with alternative technologies, while in the utility sector the consumption of fuel gas flow rate enhancing because of an increase the number of consumers. The natural gas is mostly using by domestic purpose for heating of premises and for cooking. These items of the gas utilization in Ukraine are already exceeding the NG consumption in industry. Cooking is proceeding directly in the living quarters, those usually do not meet the requirements of the Ukrainian norms DBN for the ventilation procedures. NG use in household gas stoves is of great importance from the standpoint of controlling the emissions of harmful components of combustion products along with maintenance the satisfactory energy efficiency characteristics of NG using. The main environment pollutants when burning the natural gas in gas stoves are including the nitrogen oxides NOx (to a greater extent — highly toxic NO2 component), carbon oxide CO, formaldehyde CH2O as well as hydrocarbons (unburned UHC and polyaromatic PAH). An overview of environmental documents to control CO and NOx emissions in comparison with the proper norms by USA, EU, Russian Federation, Australia and China, has been completed. The modern designs of the burners for gas stoves are considered along with defining the main characteristics: heat power, the natural gas flow rate, diameter of gas orifice, diameter and spacing the firing openings and other parameters. The modern physical and chemical principles of gas combustion by means of atmospheric ejection burners of gas cookers have been analyzed from the standpoints of combustion process stabilization and of ensuring the stability of flares. Among the factors of the firing process destabilization within the framework of analysis above mentioned, the following forms of unstable combustion/flame unstabilities have been considered: flashback, blow out or flame lifting, and the appearance of flame yellow tips. Bibl. 37, Fig. 11, Tab. 7.

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