GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 3.1 GNGTS 2024 Fig. 1 – Simplifed scheme of the adopted approach The frst three objectves aimed at gaining a body of knowledge on the chemical, physical and geotechnical propertes of marine natural gas hydrates and on the CH4-CO2 replacement mechanism. For the actvites in these three objectves, laboratory facilites of UNIPG and UNICAM are used. In additon, laboratory facilites of “D’Annunzio” University of Chiet-Pescara (UNICH) are employed since UNICH has available a patented reactor to study the kinetcs of the hydrate formaton process. Objectve 4 concerns the design and constructon of a scalable device for methane extracton and CO2 replacement. It is integrated with a methane purifcaton and CO2 recirculaton secton and tested in a seafoor simulator, where water-rich natural gas hydrates sediment reproducton and in-situ measurements will be performed. Finally the last objectve focuses on the development of a theoretcal geophysical model of the marine natural gas hydrates reservoir and fnal evaluatons on energy, environmental and economic impact of the proposed process and technological soluton. The startng point for the development of a theoretcal model is the method proposed by Tinivella (1999), which is based on the Biot-Geerstma-Smit equatons. The input data are the results of laboratory analysis, which provide various parameters such as bulk density, P-wave velocity, S-wave velocity and porosity. To estmate the stfness and compressibility of the sediments and the hydrate, these two parameters were varied untl obtaining the P-wave and S-wave velocity obtained in the laboratory.