| Title | Experiences with Different Calcite Inhibitors in the Mahanagdong Geothermal Field |
|---|---|
| Authors | Lorena M. Daco-ag and Katrina A. Belas-Dacillo |
| Year | 2010 |
| Conference | World Geothermal Congress |
| Keywords | inhibitor, calcite inhibitor, calcite scaling, calcite inhibition system, Mahanagdong Geothermal Field, Leyte |
| Abstract | There are two existing Calcite Inhibition Systems (CIS) installed in Mahanagdong sector of Leyte Geothermal Production Field. The calcite saturation indices (CSI) of wells MG1 and MG19 reached around 0.4-0.7 (log Q/K>0 indicates calcite supersaturation) and calcite mineral deposition were observed in these wells requiring periodic mechanical clearing during the initial commercial utilization in 1998. Thereafter, CIS installations were commissioned in 2001 to minimize calcite deposition and prolong the utilization of the wells before a work-over. The calcite inhibition systems have continuously functioned effectively in minimizing calcite deposition in the wellbore, extending the wells’ productivity for a longer period of almost 4 years before CIS tubing replacement and opportunity mechanical clearing is conducted. Since commissioning, the two wells have been dosed at different times with four types of calcite inhibitors chemically known to be aqueous solution of polyacrylates (3 inhibitors) and polymaleic anhydrides (1 inhibitor). This paper discusses the experiences and performances of the calcite inhibition systems in Mahanagdong in the utilization of these different calcite inhibitors. |