EXPERIMENTAL SIMULATION OF METHANE HYDRATE EXTRACTION AT HIGH PRESSURE CONDITIONS: RISK AND SAFETY ASSESSMENT

Abstract

Methane hydrate (MH) is a clathrate solid, consisting of methane molecules enclosed in frozen water, usually found in deep ocean floor at low temperature and high pressure. The deposits of this solid, similar to ice, represent more than 50% of estimated carbonaceous fuel reserves. MH is thus currently considered as one of the most potentially important future source of hydrocarbon fuel, being a more environmentally clean alternative to other fossil fuels. The low thermodynamic stability of MH, makes the exploitation hard due to a potential geo-hazard. To research various phenomena of MH, a high pressure simulator, which mimics the submarine conditions on deep ocean, has been installed. The design of this simulator includes 8 sapphire windows that ensure the best optical accessibility for using non-invasive optical methods to track the MH stability during the experiments. The goal of this study is to establish the corresponding safety precautions while using this simulator for MH production. Firstly, the amount of methane gas inside the simulator was evaluated throughout a set of experiments for the purposes of TNT equivalent method. The methane gas consumption can be measured by a pressure drop on the vessel. Moreover, MH nucleation inside sediment pores was investigated based on a pore-size vessel for microscopic observation. Finally, multi energy method could be used to establish the safety precautions.