SU1254813A1 - Geothermal heat power plant - Google Patents

Description

(21) 3826816 / 24-06, 3827026 / 24-06

(22) 12/18/84

(46) 03/15/87. Bksh. Number 10

(71) State Research Energy Institute named after G.M. Krzhizhanovsky

(72) R. B. Ahmedov, M. A. Berchenko and V. A. Vasiliev

(53) 621.311.22 (088.8)

(56) Itskovsky A.A. and others. Auxiliary equipment of geoTES turbine installations operating on highly mineralized thermal water. - V. sb. Use of geothermal energy. M .: ENIN, 1983, pp. 1336-143.

USSR author's certificate number 1038543, Kji. F 03 G 7/00, 1983.

(54) (57) 1. GEOTHERMAL HEAT-AND-ELECTRIC POWER STATION, containing production and injection wells and a degasser connected between them and a cascade of steam generators communicated by steam to a steam turbine, the condenser of which is connected through cooling water to a cooling pond characterized in that , in order to increase heat and power generation, extend service life and reduce cooling water consumption, the cooling pond is made in the form of a sectional solar pond, each section of which is equipped with a vapor pool A lem with an inclined transparent screen above the water surface, the latter in a cascade along geothermal water, the steam generator is installed at the outlet to the pool-evaporator, and at the inlet to the bottom part of at least one section of the solar pond.

2. Thermal power plant according to claim 1, characterized in that, in order to improve efficiency by reducing the consumption of make-up water, solar pond water in a single-circuit thermal power plant, a steam turbine condenser is connected to a condenser pool with an evaporator pool.

112

The invention relates to a power system and can be used in thermal power plants that absorb electricity and heat due to renewable energy sources — deep heat and solar radiation.

The aim of the invention is to increase heat and power generation, prolong the service life and reduce the consumption of cooling water, as well as improve efficiency by reducing the consumption of make-up water in a single-circuit thermal power plant. of

Figure 1 presents the scheme of a single-circuit geothermal power plant, figure 2 - scheme of a double-circuit geothermal station.

The geothermal heat and power station contains a production well 2 brought to a thermal-water bearing formation 1 and connected to it via a degasser 3 and a valve 4 a cascade of steam generators 5-7, made in the form of expanders (figure 1) or surface heat exchangers (figure 2). Steam generators 5-7 reported on the generated steam from the steam turbine 8.

The station cooling pond is made in the form of a sectional solar pond, section 9 of which has an evaporator pool 10, and section 11 - an evaporator pool 12. A transparent inclined screen 13 is installed above the water surface of the evaporator pools 10, 12.

Degasser 3 through valve 14 soy | Dinen with the entrance to the pool-evaporator 10. The last steam generator 7 in the cascade along geothermal water is connected to the outlet with pool-evaporator 10, through valve 15 with the pool-evaporator 12, and through valve 16 and a pump 17 with an injection well 18, which opens the thermal-water bearing 1. The outlets from the evaporator pools 10, 12 through heat exchangers 19, 20 are connected to the entrances to the bottom part of sections 9, 11 of the solar pond. The output from section 9 through the pump 21 is connected to the water inlet of the steam generator 7. The condenser 22 of the turbine 8 is connected by condensate to the cooling water drain line communicated with the collector of the screen 13 of the evaporator pool 10 in the case of a single-circuit thermal power plant (Fig. 1 or with steam generators 5 -7 with two 132

contour (figure 2). A pump 23 connected to section 9 of the solar pond serves to supply cooling water to the condenser 22.

Geothermal thermal power plant operates as follows.

Under the action of reservoir pressure, hot reservoir brine from thermal water bearing layer 1 through production well 2 enters the surface and is delivered to degasser 3, where the dissolved gases, including combustible ones, are separated. The degassed brine is fed through valve 4 (valve 14 is closed) to sequentially connected steam generators 5-7 with decreasing operating pressures.

When the initial temperature of the reservoir brine, less than the calculated temperature in the steam generators 5-7, the brine is fed through the valve 14 (valve 4 is closed) in the pool-evaporator 10.

Part of the brine flow from the steam generator 7 circulates through the pool 10, where the brine is evaporated to a salt concentration of 20-25%, heat exchanger 19, where the brine transfers excess heat to external consumers, the bottom part of the solar pond section 9, where the brine is heated by solar radiation to a temperature of 95 -100s, steam generator 7.

In the case of a single-circuit thermal power plant, the brine in the steam generator 7 evaporates, and the additional steam generated by this enters the low pressure part of the steam turbine 8. In a double-circuit thermal power plant, the heat obtained in section 9 of the solar pond is transferred to the steam generator 7 to the working body of the second circuit. In this way, the electrical power generated is increased.

The remaining brine flow from the steam generator 7, depending on the magnitude of the reservoir pressure in the thermal-water bearing formation 1, is directed to filling the solar pond section 11 (via valve 15, evaporator pool 12 and heat exchanger 20), to re-inject into formation 1 (through valve 16, injection pump 17 in injection well 18) to maintain reservoir pressure and extract heat from water-bearing rocks.

3125

Low-mineralized water is taken from the near-surface part of section 9 of the solar pond to cool the condenser 22. Condenser 22 water enters the upper surface of the transparent screen 13 and then enters section 9 (into the near-surface layer). On the lower surface of the transparent screen 13, vapor generated in the pool-evaporator 10 under the action of solar radiation is condensed. Fresh water collecting in the transparent screen collector is directed to the make-up of section 9 of the solar pond, compensating for the evaporation of water from its surface and maintaining the salinity gradient to eliminate convective mixing with the brine from the bottom layer. Fresh water can also be dispensed by external consumers. In evaporation pools x 10, 12, poorly soluble salts are also precipitated from the brine, which can be used for the chemical and building industries. Transparent screens also serve as protection against the wind mixing of water in a solar pond.

The flow of condensate after the condenser 22 to the outer surface of the screen 13 of the pool-evaporator 10. Together with the cooling water (figure 1) allows 34

It significantly reduces the consumption of make-up water from the solar pond, which increases efficiency.

At the first stage of operation of a geothermal station, expensive injection wells are not needed. An additional section of the solar pond with the area required for cooling the condenser is constructed. For several years, the re-injection of the spent brine into the formation, which requires a large amount of electricity, is not carried out. Brine is used to fill new sections of the solar pond. As the reservoir pressure decreases, additional wells are drilled to maintain a constant total brine production. Then comes the stage of operation of the station with partial injection of spent brine (15-20 years), the increase in the area of solar ponds continues. Subsequently, when the temperature of the extracted brine begins to drop as a result of cooling of the formation with injected water, solar ponds make the main contribution to the production of electricity, geothermal energy is used to maintain the station's power at night and in winter.