Review of Sand Control and Sand Production in a Gas Hydrate Reservoir

Abstract

Natural gas hydrate is a kind of clean energy that is still in the preliminary exploitation test stage. In recent years, research of exploration, experiment, and trial production has shown that sand production is one of the crucial issues restricting the commercial exploitation of hydrate. However, the construction of a research system for sand production and sand control of hydrate reservoirs is still incomplete. To better study the sand production mechanism and optimize the design of sand control methods in the production of gas hydrate, this review evaluates the recent research advances of sand control for hydrate production, summarizes the mechanical characteristics and dynamic response of hydrate sediment, and proposes that the analysis of the hydrate sand control design and sand production mechanism should be combined with the fluid–solid thermal coupling theory on the exploitation and that the comprehensive influence of saturation, confining pressure, temperature, pore pressure, and limited production pressure should also be considered. All of these field operation methods and parameters, using the comprehensive integration of sand control methods of production wells as the analysis boundary condition, are evaluated in depth on the influence of sand production and the degree of settlement and consolidation of a hydrate reservoir. Therefore, it will provide reference for the subsequent commercial exploitation of a hydrate reservoir and industrial application of safety production.

A Review on Submarine Geological Risks and Secondary Disaster Issues during Natural Gas Hydrate Depressurization Production

“…During depressurization production, the temperature within hydrate reservoirs changes drastically, and the thermal expansion and contraction effect causes hydrates to undergo volumetric strain, which causes sand particles in formation to move and release the constraints of the sediment skeleton, and then free flow with the fluid occurs. Sand production results from the expansion of the depressurization range and the increase in effective stress in reservoirs, so that the sand grains are stripped from the skeleton due to the destruction of the sediments [34,35]. Low production pressure is commonly used in production to promote hydrate decomposition, but increased production rates can reduce the mechanical stability of reservoir sediment, leading to extensive plastic damage.…”

“…of the sediment skeleton, and then free flow with the fluid occurs. Sand production results from the expansion of the depressurization range and the increase in effective stress in reservoirs, so that the sand grains are stripped from the skeleton due to the destruction of the sediments [34,35]. Low production pressure is commonly used in production to promote hydrate decomposition, but increased production rates can reduce the mechanical stability of reservoir sediment, leading to extensive plastic damage.…”

Micromechanism of Sand Production in the Process of Hydrate Exploitation on Depressurization in Sandy Reservoirs: A Coupled Fluid-Solid Modeling

“…3,6,11,12 Therefore, inves-tigating the mechanisms of sand production during the exploitation of hydrate reservoirs is crucial for understanding the patterns of sand production and the evolution of the physical properties within the reservoir, promoting efficient sand management. 13 It is also fundamental for the long-term and safe exploitation of gas hydrates. 13,14 Due to the high costs, high risks, and long duration associated with production trials, laboratory experiments, and numerical simulations are the main methods to explore sand production during the exploitation of gas hydrate.…”

“…13 It is also fundamental for the long-term and safe exploitation of gas hydrates. 13,14 Due to the high costs, high risks, and long duration associated with production trials, laboratory experiments, and numerical simulations are the main methods to explore sand production during the exploitation of gas hydrate. 14 The laboratory experiments have revealed the macroscale phenomenon of sand production and microscale sand production pattern.…”

Enhanced Gas Recovery for Tight Gas Reservoirs with Multiple-Fractured Horizontal Wells in the Late Stages of Exploitation: A Case Study in Changling Gas Field

“…However, currently, these studies are restricted to laboratory experiments and numerical simulations; influenced by the economics and immaturity of the technology, there are rare pilot tests carried out in practice. In addition, apart from the above technologies, to reduce the formation damages that are caused by water blocking, some researchers have developed the drying agents for EGR in tight gas reservoirs, and evaluated the basic properties, injection modes and drying effects for this type of agent [33][34][35][36][37][38]. Though it shows that this agent can greatly reduce water saturation, and improve the gas seepage capacity and the productivity, this study is an exploratory work, and is not currently used in practice.…”