| Title | Well-to-Well Two-Phase Injection using a 10in Diameter Line to Initiate Well Discharge in Mahanagdong Geothermal Field, Leyte, Philippines |
|---|---|
| Authors | Christine H. Siega, Virgilio S. Saw, Romeo P. Andrino Jr., and Garry F. CaÒete |
| Year | 2005 |
| Conference | World Geothermal Congress |
| Keywords | two-phase stimulation, well discharge, Philippines |
| Abstract | Most of the wells in the Mahanagdong Geothermal Field need to be induced in order to discharge. This is mainly because the field lies at a much higher elevation of 700-900 mASL and therefore producing wells have a low water level at the wellbore. Added to that is the absence of gas and two-phase pressure build-up in most of the Mahanagdong wells. To initiate well discharge in Mahanagdong wells with this condition, additional energy must be put into the water column of a static well to convert it to two-phase column and for pressure to build-up. There are several methods use for this purpose, namely; a) air (or gas) compression; b) gas lifting; and c) well-to-well two-phase injection. The most commonly used method at PNOC-EDC fields is the well-to-well two-phase injection. This paper discusses in details the procedures of a well-to-well two-phase injection using two different diameter sizes of injection lines. Previous practice is done through the use of a 2" diameter injection line connected to the wing valve of each well. Using this line size, injection time is longer, ~ 2 days, with the chances of a successful discharge seldom achieved. In contrast, the use of a 10in diameter line has greatly reduced the time for two-phase injection and improved significantly the chances of a successful well discharge. |