ForDiMHy-PP Project

Oil transportation in deep sea pipelines encounters regularly pressure and temperature conditions which correspond to the thermo dynamical condition of hydrate formation. The formation of hydrate plugs is firstly a problem of flow insurance. The best strategy is to avoid their formation (see ARCHIMEDE project) by means of different technologies (thermodynamic additives or kinetic additives, insulation of pipelines, cold flow,…etc). But, once the plug is formed, one need to proceed to its dissociation.
The Formation and Dissociation of Methane Hydrate Plugs in Pipeline is a project which aims at producing experimental data and modelling to estimate the timedissociation of hydrate plugs.

It is sequenced in the following parts :

2001-2004 : The project has produced experimental data coupled with a numerical model and a approximate solution to predict dissociation time of low size hydrate plugs (heat transfer limited model). The model is coupled to an experimental approach where hydrate plugs are dissociated by the method of symmetric depressurisation, both in a specially designed apparatus and a classical batch reactor. The agreement between the estimation of the model and the experimental data. The model has been also validated on literature data. The simplicity of the approximate equation presents an advantage in estimating the time of hydrate plug dissociation in pipelines without computing (see NGuyen Duc et al, 2006)

2004- 2007 : The project aims at coupling heat and mass transfer to be able to model large scale plugs in which a pressure gradient appears during dissociation and modify the driving forces and mass transfer. This project is couple with the work ForDiMHy-S project.