Application of the Snhc Gas Equilibria Method in Monitoring Reservoir Processes in Tongonan Geothermal Field, Philippines

Abstract

The SNHC gas equilibriamethod involves three reactions, namely the Fischer-Tropsch the pyrite-magnetite (HSH), and the pyrite-magnetite-ammonia (SNHC). Solving simultaneously the equilibrium equations of these reactions generatesthe reservoir temperature the reservoir steam fraction and the partial pressure of The variation in the trends of the calculated reservoir parameters with time indicates specific physical process. Selected wells in the production sector demonstrated the processes of interplay of feed zone with varying well dischargepressure, the reservoir pressure drawdown, and the mixing of reinjected fluids. On field-widebasis, the contours of these three parameters depicted the temperature, pressure and steam fraction distribution, thereby, delineatingthe areas affectedby reservoir-widedrawdown.