Geothermal fields in Iceland

To find the mass ratio of vapor to liquid produced, we note the discharge enthalpy //tot and sampling pressure Ps from Table 23.2. From the steam tables (Keenan et al., 1969), we find the sampling temperature 7) corresponding to the boiling point at Ps, and the enthalpies //uq and Hyap of liquid water and steam at this 

enthalpy is given in kcal kg-1, temperature in °C, and pressure in atm. Note that the sampling temperatures are considerably lower than subsurface temperatures because of the energy used to produce the vapor phase. 

we need to calculate the amount of each component in the vapor phase. At room temperature, the vapor separates into a condensate that is mostly water and a gas phase that is mostly CO2. Table 23.2 provides the composition of each. The mole number of each component (H2O, CO2, and H2S) in the condensate, expressed per kg H2O in the liquid, is derived by multiplying the concentration (g kg-1) by the vapor fraction Xvap and dividing by the component s mole weight. 

The mole numbers per kg liquid for the gases (H2O, CO2, H2S, H2, and CH4) that separated from the condensate are obtained by multiplying the volume fraction of each by (7) the volume of gas per kg condensate, (2) the mass fraction Zvap of the vapor phase produced, and (3) the number of moles per liter of gas. The latter value can be calculated from the ideal gas law PV = R7k at 20 °C and 1 atm pressure, there are 0.0416 moles per liter of gas. The final values for each well, 

To run REACT for the Reykjanes 8 well, we start by defining the initial system TDS = 39124 

TABLE 17.2 Chemical compositions of water and steam discharged from wet-steam geothermal wells in Iceland (Arnorsson et al., 1983) 

---

Geothermal power plant located in a lava field in Blue Lagoon, Iceland. (Corbis-Bettmann)... 

Brandsdottir, B., Franzson, H., Einarsson, P., Arnason, K. Kristmannsdottir. H. 2002. Seismic monitoring during an injection experiment in the Svartsengi geothermal field, Iceland. Jokull, 51, 43-52. 

Eysteinsson, H. 2000. Elevation and gravity changes at geothermal fields on the Reykjanes Peninsula, SW-Iceland. In Proceedings World Geothermal Congress, 2000, Kyushu-Tohoku, Japan, 28 May-10 June 2000, 559-564. 

Hardardottir, V., Kristmannsdottir, H. Armannsson, H. 2001. Scale Formation in Wells RN-9 and RN-8 in the Reykjanes Geothermal Field, Iceland. Water-Rock Interaction (WRI-I0). Balkema, Rotterdam, 851-854. 

The Larderello field in Tuscany, Italy, first began to produce electricity in 1904 and developed over the next 10 yr to a capacity of 250 KW. In Japan, Beppu was the first site for experimental geothermal work in 1919 and these experiments effected a pilot plant in 1924 producing 1 KW of electricity. Somewhat earlier than this the Japanese began to use geoheat to heat their greenhouses. In Iceland, municipal heating was... 

Fig. 10. Na+/H+ (a) and Ca+2/(H+)2 (b) activity ratios in selected springs (circles) and geothermal aquifer waters (dols). Individual ion activity ratios are in moles/kg. The data for springs are from Yellowstone, Wyoming, USA, and Iceland (many different fields). The drillhole data are from Guatemala (Zunil), Iceland (many different fields), Japan (Onuma, Fusime), New Zealand (Ngawha, Wairakei), and Nicaragua (Momotombo).

---