Correlation of Gas Quality with Hydrodynamic Parameters in Transmission Networks

Abstract

Natural gases are a mixture of hydrocarbons. Their composition determines the basic variables that need to be taken into account in the calculation of transport or gathering systems. In the daily operation of gas gathering and transport networks, the available composition measured by online systems is reduced. In the usual composition a pseudo-component called C6+ (or C7+) is used. If this component is defined from the complete chromatograph analysis of gas, the properties are established through a lumping procedure. Online chromatographic analysis is done on a small group of basic components, usually for heavy components by introducing a pseudo-component, in this paper called C6+. In this paper we will show how to determine the properties of the pseudo-component according to the measured density of the mixture and its dynamics through the network. Generally, transport networks operators are interested in operating them so as to maximize the benefit and reduce any penalties. For this they have SCADA systems, which provide information on transport parameters and gas quality at the monitored points. The overall picture of the network and its short and medium-term evolution is achieved with a powerful simulator. Managing the gas quality from the entry points to the exit points must be made dynamically by the simulator. In this paper we will present results obtained with the ADMODUNET simulator produced by NetGas R&D based on the company’s agreement.