Research progress on methane production from natural gas hydrates

Abstract

A review of the research on methane production from gas hydrates, including the research on the characteristics of gas hydrate reservoirs, production methods, numerical simulations and field production tests.

Exploring the effects of four important factors on oil–CO2 interfacial properties and miscibility in nanopores

“…In the oileld application of a CO 2 injection project, the injected pure CO 2 will likely contain some solution gas, the primary component of which is CH 4 . 32 In this study, the effects of CH 4 in an impure CO 2 sample on the IFTs, interfacial thicknesses, and MMPs are purposely studied by adding respective 0.10, 0.35, and 0.50 CH 4 in mole fraction into the pure CO 2 to obtain three different impure CO 2 samples. Fig.…”

Prevention of Potential Hazards Associated with Marine Gas Hydrate Exploitation: A Review

“…Choosing the most effective method for gas production from MGHs involves assessing a variety of factors to achieve the simplest, most practical, and environmentally safe method of production. Five methods are mentioned in the Introduction, their production benefits and risks are presented here as follows [6,60]: Figure 11. Volumetric method in resource appraisal [56].…”

“…The results of the production tests and sampling studies have found that the crystal structure, sediment morphology and occurrence characteristics of NGHs show great diversity ( Figure 3). This difference means that development of these resources will be complicated [6]. There is the potential for submarine landslides, climate warming, marine ecological damage and other hazards, if MGHs are not developed carefully.…”

“…The difficulty of developing MGH reservoirs varies in a continuum from low in sandy reservoirs, then permeable clay reservoirs, then cold spring-related massive reservoirs, to high in non-permeable clay reservoirs. Each reservoir-type can be subdivided into three types according to recoverable value: Class I, Class II and Class III [6,12]. Class I is that one hydrate bearing layer covers on a two-phase fluid zone with free gas which is considered to be the most suitable reservoir for natural gas production.…”

“…As a non-traditional fossil fuel, natural gas hydrates (NGHs) are the subject of increasing research since their discovery in the 1960s [3,4], because of their high calorific value and potential utilization. NGHs (combustible ice) are non-stoichiometric crystalline compounds that form ice-like solid structures of gas (i.e., usually methane, ethane, propane and lower order hydrocarbons [5]) and water in a low-temperature (2-18 • C) or high-pressure (3.5-14.5 MPa) environment [6][7][8]. These conditions occur in near-surface, deep-water marine sediments and in terrestrial permafrost areas that are widely distributed around the world (Figure 1).…”