| Title | Antiscalant Injection Trial at Kawerau Geothermal Field, New Zealand |
|---|---|
| Authors | Robson, Quentin; Blair, Alan; Perales, Ken |
| Year | 1990 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Brine Technology; Production; Power Generation; New Zealand; Kawerau; Calcium Carbonate; CaCO3; Inhibitor; Scale; Capillary Tubing; Chemical Inhibiting; Brine Technology; Calcite; Phosphonates; Polymers |
| Abstract | Scale formation is one of the main problems associated with the exploitation of water dominated geothermal fields. The deposition of calcium carbonate scale is a severe operational problem in the Kawerau field in New Zealand, necessitating annual workovers to cleanout the calcite in the casings. Investigations into alternative methods of scale control were conducted. The most promising appeared to be the use of scale inhibitors injected down hole via capillary tubing to a depth below the flash point. Laboratory tests were conducted to find an inhibitor that would not degrade at the high temperatures encountered in the Kawerau field. Upon selection of a suitable chemical a field trial followed. Teething problems with the surface injection system has resulted in well rundown, however at time of writing the run down was 35% of that expected with no injection of inhibitor. |