Localization of fugitive methane emission from natural gas distribution network of Titas Gas

Abstract The aim of this paper is to localize the fugitive leaks from the above ground facilities of the existing system of Titas Gas (TG) after developing mathematical model for fugitive emission. Soap screening techniques and Gasurveyor 500 series instrument were used in this study for detecting potential leaks. Leaked gas was quantified using either Hi-Flow gas sampler or bagging measurements system. The results show that the respective potential gas leaking point of City Gate Station (CGS), commercial Regulating and Metering Station (RMS), industrial RMS, residential RMS and Town Bordering Station (TBS)/ District Regulating Station (DRS) are scrubber dump valve (average leak rate 217.00 L/min), insulating point (average leak rate 4.04 L/min), tube fitting connector (average leak rate 8.00 L/min), connector (average leak rate 1.55 L/min) and pressure relief valve (average leak rate 437.92 L/min). Fugitive methane emission can be reduced by stopping leaks of fittings or components having high KLeak value.

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The static and dynamic characteristics of a pressure relief valve with a proportional solenoid-controlled pilot stage

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1243/0959651021541516 ◽

2002 ◽

Vol 216 (2) ◽

pp. 143-156 ◽

Cited By ~ 19

Author(s):

R Maiti ◽

R Saha ◽

J Watton

Keyword(s):

Mathematical Model ◽

Dynamic Characteristics ◽

Dynamic Behaviour ◽

Practical Experience ◽

Pressure Relief Valve ◽

Relief Valve ◽

Pressure Relief ◽

Static And Dynamic Characteristics ◽

Good Comparison ◽

The Mathematical Model

The steady state and dynamic characteristics of a two-stage pressure relief valve with proportional solenoid control of the pilot stage is studied theoretically as well as experimentally. The mathematical model is studied within the MATLAB-SIMULINK environment and the non-linearities have been considered via the use of appropriate SIMULINK blocks. The detailed modelling has resulted in a good comparison between simulation and measurement, albeit assumptions had to be made regarding the solenoid dynamic characteristic based upon practical experience. The use of this characteristic combined with additional dynamic terms not previously considered allows new estimations of internal characteristics to be made such as the damping flowrate. The overall dynamic behaviour has been shown to be dominated by the solenoid characteristic relating force to applied voltage.

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Bond Graph Modeling of a Two-Stage Pressure Relief Valve

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4023768 ◽

2013 ◽

Vol 135 (4) ◽

Cited By ~ 5

Author(s):

Osama Gad

Keyword(s):

Mathematical Model ◽

Graph Model ◽

Bond Graph ◽

Fluid Power ◽

Pressure Relief Valve ◽

System Component ◽

Bond Graphs ◽

Relief Valve ◽

Two Stage ◽

Pressure Relief

This study examined the use of bond graphs for the modeling and simulation of a fluid power system component. A new method is presented for creating the bond graph model, based upon a previously developed mathematical model. A nonlinear dynamic bond graph model for a two-stage pressure relief valve has been developed in this paper. Bond graph submodels were constructed considering each element of the studied valve assembly. The overall bond graph model of the valve was developed by combining these submodels using junction structures. Causality was then assigned in order to obtain a computational model, which could be simulated. The simulation results of the causal bond graph model were compared with those of a mathematical model, which had been also developed in this paper based on the same assumptions. The results were found to correlate very well both in the shape of the curves, magnitude, and response times. The causal bond graph model was verified experimentally in the dynamic mode of operation. As a result of comparison, bond graphs can quickly and accurately model the dynamics in a fluid power control system component. During the simulation study, it was found that nonlinearity occur due to three factors: changes in pressure, which cause nonlinear velocity changes of the flow rate; changes in the throttling area of the valve restriction, which usually changes nonlinearly; and changes in the discharge coefficient of the throttling area of the valve restriction, which does not remain constant.

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