Natural gas hydrate is a new potential energy, so how the gas can be effectively produced from hydrate deposits becomes a hot research topic. Heat stimulation is regarded as another important way for producing hydrate besides depressurization. However, production efficiency and economic feasibility of gas production by heat stimulation are not well understood. In this paper, a physical model for predicting gas production from hydrate deposits by heat stimulation through a vertical well is constructed. The model defines a laminar hydrate system of unit thickness. The reservoir system is discretized densely. We numerically simulate the production potential of hydrate deposit through thermal stimulation by employing the TOUGH+HYDRATE simulator with the characteristic parameters of Shenhu hydrate on the northern continental slope of the South China Sea. Then, we compare and analyze the efficiency of heat stimulations with a pure depressurization operation. Our research shows that the radioactive radius of the high-temperature heat source at the well is very small and that the hydrate dissociation rate is slow. The contribution of thermal injection operation is very small in the inter-productions of heat stimulation and depressurization, and the hydrate dissociation in the processes are mainly aroused by the operation of depressurization.
SU Zheng
,
HE Yong
,
WU Neng-you
. Numerical simulation on production potential of hydrate deposits by thermal stimulation[J]. Journal of Tropical Oceanography, 2012
, 31(5)
: 74
-82
.
DOI: 10.11978/j.issn.1009-5470.2012.05.011
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