Baca geothermal demonstration project. Equation-of-state for water-carbon dioxide mixtures: implications for Baca reservoir

Abstract

An equation-of-state package for water-carbon dioxide mixtures has been constructed from available thermodynamic data that covers the range interest to the Baca reservoir system. The package has been to examine the thermodynamic state of the Baca reservoir fluid for conditions o f temperature, pressure and C02 content believed to bracket conditions existing at the production depth of the wells in the Redondo Creek area. It is shown that the reservoir fluid may be either all-1 iquid or two-phase at various well locations and depths, depending on the C02 content. It i s also shown that the C02 content at reservoir conditions cannot be re1 iably inferred from pressureltemperature measurements made on flowing wells. The eq on-of -state package has been incorporated into a general purpose thermal reservoir simulator and a series of calculations made which show that the C02 content of the produced fluid be less than or greater than that of the reservoir fluid, The char of the produced fluid are sensitive to the GO2 content TABLE OF CONTENTS SECTION 1 INTROOUCTION 1.1 . Introduction 1.2 Scope of the Report 1.3 Summary and Conclusions 1.4 Recommendations for Future Study SECTION 2 EQ U AT I ON-OF4 TATE PACKAGE 2.1 Introduction 2.2 Summary 2.3 Calculational Procedure 2.4 Partition of Carbon Oioxide 2.5 Specific Volume and Energy of Mixture Components 2.6 Viscosity of Mixture Components 2.7 Thermal Conductivity of Mixture Components 2.8 Energy of Solution SECTION 3 EFFECTS OF C02 ON BACA RESERVOIR STATES P a g e 3.1 Introduction 3.2 Summary 3.3 Effects of CO2 on Thermodynamic States 30 3.5 EFFECTS OF C02 ON WELL FLOWING TESTS 3.4 Effects o f CO on Baca Reservoir Conditions Need for Chem ? cal Measurements of Baca Discharge F1 ui ds SECTION 4

Long‐term variations of the Campi Flegrei, Italy, volcanic system as revealed by the monitoring of hydrothermal activity

“…Dissolution of CO 2 in water is described according to Henry's law and the heat of solution effects are taken into account. Thermophysical properties of CO 2 are evaluated based on the model by Sutton and McNabb [1977], and the viscosities of water vapor-carbon dioxide mixtures are described following Pritchett et al [1981]. Heat is transferred both by conduction and convection and the model includes sensible and latent heat effects.…”

A Numerical Model of Tracer Transport in a Non-isothermal Two-Phase Flow System for $${\text{ CO}}_2$$ Geological Storage Characterization

“…For the dynamic viscosity of CO 2 , we use the model utilized in the TOUGH2 simulator (Pruess et al 1999;Battistelli et al 1997), where viscosity of CO 2 is a function of pressure and temperature and calculated using the correlation quoted by Pritchett et al (1981). This formula is based on data tabulated by Vargaftik (1975).…”

TOUGH2 software qualification

“…It accounts for non-ideal behavior of gaseous CO,, and dissolution of CO, in the aqueous phase according to Henry's law with heat-of-solution effects. The thermophysical property correlations are based on the model of Sutton and McNabb (1977); a formulation from Pritchett et al (1981) is used for the viscosity of vapor-CO, mixtures. Specifications and parameters of EOS2 are summarized in Table 5.…”