| Title | Inventory of Steam Sources at Mindanao Geothermal Production Field |
|---|---|
| Authors | Gabriel M. Aragon and Benson G. Sambrano |
| Year | 2007 |
| Conference | PNOC-EDC Geothermal Conference |
| Keywords | |
| Abstract | The different sources of steam production were quantified using the H2S-H2 gas pair from the latest geochemical data obtained from the geothermal wells in Mindanao Geothermal Production Field. The calculation was based on the method developed by Arnosson in 1990 in evaluation the boiling processes and initial steam fraction in the geothermal reservoirs. The calculations showed that more that 50% of the steam being produced by the geothermal field was attributed to enhanced vaporization due to heat flow from the rock to the boiling water. The production well affected by the reinjection returns coming from Matingao and Kullay injection sinks have minimal steam produced through enhanced vaporization and bulk of the steam production is mainly ascribed to plain adiabatic boiling. This shows that there is significant cooling at the reservoir rock in the Marbel production sector brought by the persistent inflow of cooler injected fluids. The wells drilled in Sandawa sector, the hottest region and postulated upflow zone of the geothermal field, gave higher % steam produced by enhanced vaporization which ranged from 40 to as high as 80. The vapor dominated and high enthalpy wells of the field are by products of enhanced vaporization and phase segregation of steam from water. The phase segregation is very evident to vapor dominated wells wherein the steam dominates in the discharge because the water component was left behind in the reservoir due to faster mobility of vapor that the liquid phase. |