(215b) Drag Model Development and 3-Phase Simulation of Methane Production from a Gas Hydrate Reservoir

Deniz Hinz, Hamid Arastoopour and Javad Abbasian

Department of Chemical and Biological Engineering

Wanger Institute for Sustainable Energy Research (WISER)

Illinois Institute of Technology, Chicago, IL

ABSTRACT

Global estimates of resource-grade natural gas from hydrates range from 10,000 trillion cubic feet (tcf) to greater than 100,000 tcf. When compared with the approximately 2200 tcf of U.S. technically recoverable natural gas reserves as of 2012, one can grasp the incredible scale and conceivable global impact of hydrates. In recent years, the 570 tcf of technically recoverable shale gas resources has provided the U.S. considerable economic stimulus and affordable means of decreasing coal consumption. This means the potential impact of hydrate resources will result in very significant economic growth. As the world undergoes the transition into a sustainable energy society, natural gas is the cleanest fossil energy option.

The theoretical potential of hydrates is immense, but production testing and research remain lacking, which has led to the development of numerous hydrate production numerical simulators for consolidated porous medium hydrate reservoirs; however considerable evidence exists suggesting unconsolidated flow behavior. Production data from the JOGMEC Mallik 2L-38 well in Alaska reported extensive sand production, leading to repeated pump failure in the 2007 testing period and the installation of sand screens prior to the successful 2008 testing period.

Pore-scale inhomogeneities intrinsic to the reservoir are magnified during the hydrate dissociation and sand production processes, causing homogeneous permeability models such as the Kozeny-Carman equation to deviate significantly from experimental results. Therefore, a three-phase flow model which includes momentum and continuity equations for each phase and constitutive models for the drag force between gas and liquid phases with the hydrate-bearing sediment were developed. Our drag force models quantify the pore-scale inhomogeneity and simulate the evolution of high-permeability regions in the reservoir. Our numerical simulation prediction of the methane production agreed with the production data from the JOGMEC Mallik 2L-38 well in Alaska.