Predictive Modelling of Gas Diffusion and Solubility in Polymers for Offshore Pipelines

For the last 35 years flexible pipes have been a key component in offshore oil and gas production. The pipeline has a polymeric inner liner that has the function of preventing the escape of gases and damage to the other layers in the structure. Inside the pipeline, the carbon dioxide will be transported at high temperature and pressure.

The propose of the study is:

Experimental measurements of solubility and permeability of gases (CO2 and CH4) as well as theirs mixtures in selected polymers (XLPE, PVDF and PA11) as a function of temperature, pressure, pressure drop and composition. The tests will carried at a range of temperatures up to 90 °C and pressures up to 650 bar.

The solubility is measured through a Magnetic Suspension Balance (MSB) and the permeability is obtained from a 2-D permeation cell; both equipment are suitable for the desired range of pressures and temperatures;

Prediction through modelling the above properties based on the equation of state sPC-SAFT. It is intention that the model will also account for volumetric properties of the polymer (such as polymer swelling). A model for transport of gases in polymers will also be developed. 

The emphasis for the model will be on its predictive ability and the possibility of gaining physical insight into the processes described (solubility, diffusion, swelling), i.e. going beyond correlation and data-fitting. The project will therefore have a considerable experimental component running concurrently with and supporting the model development, the experimental measurements will be carried at DTU and possibly at NOV.

Supervisor: Assoc. Prof. Nicolas von Solms, nvs@kt.dtu.dk

Co-supervisor: Prof. Georgios Kontogeorgis, gk@kt.dtu.dk


Contact

Nicolas von Solms
Professor
DTU Chemical Engineering
+45 45 25 28 67

Contact

Georgios Kontogeorgis
Professor
DTU Chemical Engineering
+45 45 25 28 59