| Title | Thermal Structure of Kuju Volcano, Central Kyushu, Japan and an Estimation of the Heat Extraction Rate from the Volcanic Geothermal Reservoir |
|---|---|
| Authors | Sachio Ehara and Koji Morita |
| Year | 1995 |
| Conference | World Geothermal Congress |
| Keywords | thermal structure, volcano, hydrothermal system, volcano energy, heat extraction, heat exchanger |
| Abstract | Kuju volcano is situated in the Reppu Shimabara volcanic graben in central Kyushu, Japan. Geophysical and geochemical studies indicate the most of the magma body is not molten at present hilt still maintains high temperatures of 400-700oC at a death of 5km. It is also suggested that the volcanic hydrothermal reservoir beneath the solfatara field and the central part of the magma body is a two phase reservoir heated by magma origin fluids. Based on the above thermal model, the rate of heat extraction with downhole Coaxial. Heat Exchanger (DCHE) was estimated by a numerical simulation. As a result it is indicated that more than 16MW of thermal energy can be extracted from a single well of 3000m in depth by the DCHE. |