Sensitivity Analysis of Parameters Governing the Recovery of Methane from Natural Gas Hydrate Reservoirs

Abstract

Naturally occurring gas hydrates are regarded as an important future source of energy and considerable efforts are currently being invested to develop methods for an economically viable recovery of this resource. The recovery of natural gas from gas hydrate deposits has been studied by a number of researchers. Depressurization of the reservoir is seen as a favorable method because of its relatively low energy requirements. While lowering the pressure in the production well seems to be a straight forward approach to destabilize methane hydrates, the intrinsic kinetics of CH 4 -hydrate decomposition and fluid flow lead to complex processes of mass and heat transfer within the deposit. In order to develop a better understanding of the processes and conditions governing the production of methane from methane hydrates it is necessary to study the sensitivity of gas production to the effects of factors such as pressure, temperature, thermal conductivity, permeability, porosity on methane recovery from naturally occurring gas hydrates. A simplified model is the base for an ensemble of reservoir simulations to study which parameters govern productivity and how these factors might interact. OPEN ACCESSEnergies 2014, 7 2149

Assessment of Gas Production Potential from Hydrate Reservoir in Qilian Mountain Permafrost Using Five-Spot Horizontal Well System

“…In order to realize the use of the methane gas trapped in gas hydrates as a kind of energy resource, people have proposed various kinds of production techniques for gas extraction from hydrate deposits, such as depressurization [9][10][11][12], thermal stimulation [13][14][15], inhibitor injection [16,17], and CO2 replacement [18,19]. In general, depressurization is considered to be the most practical and economic method for field-scale hydrate decomposition due to its technical effectiveness and the fast propagating rate of the pressure wave [12].…”

Cyclic methane hydrate production stimulated with CO2 and N2

“…This simulator was used to simulate hydrate reservoir production in the Mount Elbert area [27], and it obtained long-term production characteristics similar to other tested simulators. In addition, it has also been used for sensitivity studies of CH 4 hydrate production [28], economic studies [29], gas production behavior [30], and CO 2 hydrate formation in depleted gas reservoirs [31]. The base model was established using CMG-STARS by referring to the reservoir and operation parameters of the Ig_nik Sikumi Field production trial.…”

Permeability Models of Hydrate-Bearing Sediments: A Comprehensive Review with Focus on Normalized Permeability

“…However, the exponent N lacks a clear physical meaning, and its value is difficult to determine, ranging from 2.6-14 for different hydrate formation methods [44] and from 1.25-25 for different hydrate pore habits [40]. Therefore, there is still much controversy here regarding the determination of the value of exponent N. Compared to the widely used Tokyo model, the LBNL model [45], the CMG built-in model [46], and the Civan model [47] were less adopted but have also been written into some special simulators for gas production from hydrate reservoirs during NGH exploitation. For example, the LBNL model was incorporated into EOSHYDR/Tough2 [48,49] and the CMG built-in model was employed by CMG STARS.…”