Marlene LUND, Graduate Researcher at EQUINOR, 2018Marlene LUND, graduate reseacher at EQUINOR ASA, presented (PDF, 998 Kbytes) on the simulation of new gas processing concepts at the CAPE-OPEN 2018 Annual Meeting.

Logo of Equinor ASAMarlene began by explaining where Equinor comes from. The Norwegian oil and gas giant Statoil changed its name to Equinor on May 16, 2018. Equinor was formed by combining “equi”, the starting point for words like equal, equality and equilibrium, and “nor” signaling a company proud of its Norwegian origin, and who wants to use this actively in its positioning.

Equinor conducts major projects like subsea compression and offshore floating wind (in operation) or the unmanned production platform, supported from host (UPP™)in which the values carried by the new name are reflected.

The Unmanned Production Platform (UPP™) calls for new technologies like simpler processes with less maintenance such as Gas-2-Pipetm. It is a concept for treating gas to rich gas quality in a unmanned facility. The objective for Gas-2-Pipe™ is to reduce capex/opex intensive topside modifications and topside weight and space constraints by utilizing the established infrastructure and host facilities in a flexible way. The process concept treats a gas dominated well stream in order to meet the so called rich gas transport specifications. Gas is treated in two steps where hydrocarbon dew point is obtained by sea water cooling and pressure reduction to form a gas and a liquid phase. Water content in the separated gas is reduced by injecting lean glycol through a compact mixer unit and separating out the rich glycol from the gas in a separation unit. Gas is also cooled by sea water in the dehydration process. A single- or two-stage dehydration process may be used.

Gas-2-Pipe™ relies on a fundamental understanding of the efficiency of the water removal process and on the ability to predict the solubility of glycols in natural gas. Improved thermodynamics for hydrocarbon/water/glycol systems are necessary in simulations for the design and monitoring of gas treatment plants.

In order to fill the technology gaps, Equinor relies on collaboration with Denmark Technical University and on Equinor in-house thermodynamic model, called Neqsim. Developed in Java, the core code has been wrapped as a CAPE-OPEN Process Modelling Component about five years ago, using C# as a programming language.

A number of CAPE-OPEN related challenges need to be overcome: speed of simulations is too slow when using Neqsim in a process simulator, stability and speed of convergence of algorithms need to be improved, interpretation of errors remains too difficult while the experience in development of the CAPE-OPEN layer is limited.