Proceedings of the 7th New Zealand Geothermal Workshop 1985. Calculation of calcite and anhydrite scaling potential in geothermal wells. New Zealand Geothermal Workshop [7, 6-8 Nov. 1985, New Zealand].

Cope, D.M. Bogie, I. Harvey, C.C.

1985

1067
CIENA

0-86869-065-1

Both calcite and anhydrite depositions occurs in geothermal wells in the Philippines. In an attempt to predict calcite deposition and determine a deposition mechanism for anhydrite the solubilities of these minerals have been calculated using a computer algorithm which calculates chemical speciation in saline fluids at high temperatures and which can model the processes of flashing and mixing. Calcite and anhydrite are both close to saturation in preflashed geothermal fluids in the Philippine geothermal fields studied. After flashing however, calcite is computed to become significantly oversaturated in the majority of wells studied whereas anhydrite is computed to become significantly undersaturated. Calcite scaling problems, however, have been restricted to low temperature wells. Mixing of high sulfate waters with moderately calcium rich reservoir fluids is concluded to be a strong depositional mechanism for anhydrite deposition in wells and may provide a technique to control high sulphate inflows. ABSTRACT. INTRODUCTION. METHOD. RESULTS OF WELL MODELLING. DISCUSSION. REFERENCES. ACKNOWLEDGEMENTS.

Presenta gráfs. y tbls.

FILIPINAS; ENERGIA GEOTERMICA; GEOTERMIA; POZOS GEOTERMICOS; MINERALES; GEOQUIMICA; DEPOSICIONES DE CALCITA;