Photo: Thorkild Christensen


Chemicals for Gas Processing

Traditionally cubic equations of state have been applied to describe phase equalibria in an oil-gas mixture. Cubic equations of state are relatively simple and hold an outstanding track record within gas-liquid phase equilibria solutions related to oil recovery. However, current oil recovery depends on a range of chemicals needed to facilitate production, i.e. polymers, surface active substances, emulsion breakers and hydrate inhibitors.
The major purpose of CERE’s joint industrial project Chemicals for Gas Processing (CHIGP) is to develop and maintain a rigorous thermodynamic model, the CPA (Cubic-Plus-Association) equation of state. CPA is a model useful for thermodynamic calculations for mixtures of relevance to the petroleum and chemical industries e.g. mixtures of oil and gas with gas hydrate inhibitors (methanol, glycols) and organic acids.

Such polar and hydrogen bonding compounds are difficult to handle with conventional models and CPA offers a successful alternative and is a good compromise between accuracy and simplicity.

The CPA and other tools developed in the project have also proved their worth in other contexts outside the oil industry.

The current industrial participants are Statoil, GASSCO, BP and PETROBRAS. The project was initiated in 2003. Total, Mærsk Oil and Dong Energy have been previously participated tin the project. The project is coordinated by Professor Georgios Kontogeorgis, CERE.

Results from CHIGP are disseminated to the participants via CERE’s web-site and a special project web-site The deliverables include software in form of CAPE-OPEN compliant modules and user-models for the ASPEN process simulator. In this way the results can be used by industry almost as soon as they are produced. Moreover, the results are presented in progress meetings held twice per year.

Head of project: Prof. Georgios Kontogeorgis,

PhD: Bjørn Maribo-Mogensen,

PhD student: Michael Frost,

PhD student: Alay Aria,

PhD student: Anders Schlaikjer,

Post Doc: Xiaodong Liang,


CHIGP website


Georgios Kontogeorgis
DTU Chemical Engineering
+45 45 25 28 59


Xiaodong Liang
Associate Professor
DTU Chemical Engineering
+45 45 25 28 77