Geothermal energy. Geothermal resources of Russia

Geothermal energy in Russia can provide the population with certain resources for municipal, industrial and agricultural needs.

Russia and the former Soviet Union have been drilling for hot water and steam from deep within the Earth for more than 60 years. Today, almost the entire territory of the country is well studied. It turned out that many regions have reserves of hot water and steam with temperatures from 50 to 200 0 C at depths from 200 to 3000 m.

Geothermal springs in Russia

The Central region, North Caucasus, Dagestan, Siberia, the Baikal Rift zone, Krasnoyarsk Territory, Chukotka, Sakhalin, Kamchatka Peninsula and the Kuril Islands have the richest geothermal energy resources to produce up to 2000 MW of electricity and more than 3000 MW of heat for the district heating system. The use of geothermal resources in Russia is especially important for supplying the northern territories of the country.

In Russia, due to the cold climate, more than 45% of the total energy resources are used to supply heat to cities, settlements and production complexes. Up to 30% of these energy resources in some areas can be provided by using heat from the bowels of the Earth.

The use of geothermal energy is planned to be carried out in the following regions of Russia: in the Krasnodar Territory (heat supply for the city of Labinsk, as well as a complex in the village of Rozovy), the Kaliningrad region and Kamchatka (heat supply for the Elizovskaya and Pauzhetskaya power plants with a capacity of 12 MW and the expansion of the existing Mutnovskaya GeoPP to 50 MW, where secondary steam is used to produce electricity.

Economic and political changes that have occurred in Russia greatly influence how the electric power industry develops.

Electricity in Russia is mainly based on the use of fossil fuels and the operation of nuclear and hydroelectric power plants. Currently, geothermal energy is relatively modest, although the country has significant resources.

The current economic situation in Russia depends on the development of its energy potential. Economic difficulties make the problem of energy supply significant, especially in the northern and eastern regions of the country. Under these circumstances, it is quite natural that regions should strive to use their own energy resources and develop renewable energy sources. In the regions of the Far East, Sakhalin, the Kuril Islands, and Kamchatka, the use becomes economically feasible.

There are several main regions that are promising for “direct” use (heat supply for residential buildings and industrial buildings, heating greenhouses and soil, in livestock farming, fishing, in industrial production, for production chemical elements, increasing oil recovery, for melting frozen rocks, in balneology, etc.), as well as for heat using heat pumps and generating electricity at a binary cycle geothermal power station (geothermal power plant).

One of them, the region (Kamchatka and the Kuril Islands) is located in the area of active volcanoes, the most promising area for the “direct” use of geothermal energy and the construction of geothermal power plants. So far, 66 thermal water and steam wells have been studied in Russia. Half of them are in operation, providing about 1.5 million Gcal of heat per year, which is equal to almost 300 thousand tons of standard fuel.

Southern part of Russia

Dagestan in the North Caucasus is one of the largest in the field of geothermal energy development. The total amount of resources at a depth of 0.5-5.5 km makes it possible to obtain approximately 4 million m 3 /day of hot water. Currently, more than 7.5 million m 3 /year of water with a temperature of 50-110 0 C is used in Dagestan. Among them, 17% are considered hot; 43% for district heating; 20% for greenhouses and 3% for balneology and mineral water production. In Dagestan, about 180 wells have been drilled at depths from 200 to 5500 m. Cities such as Kizlyar, Tarumovka and Yuzhno-Sukhokumsk have unique reserves of hot water. For example, the Tarumorskoye field has reserves of hot water of high mineralization (200 g/l) with temperatures up to 95 0 C. Six wells were drilled to a depth of about 5500 m, the deepest wells in Russia. Tests indicate high well reservoir permeability between 7500 and 11000 m 3 /day and wellhead pressure of 140-150 bar.

In the Caucasus and Ciscaucasia, thermal waters were formed due to multilayer artesian basins in sediments of the geological era of the Mesozoic and Cenozoic.

The mineralization and temperature of these waters vary significantly: at depths of 1-2 km - from 0.5 to 65 g/kg and from 70 to 100 0 C, respectively, while on the Scythian platform at depths of 4-5 km - from 1 to 200 g/kg and from 50°C to 170°C.

In Dagestan, the total amount of explored thermal water reserves is 278 thousand m3/day, and with the use of water reservoirs - 400 thousand m3/day. The thermal potential here is equivalent to the annual replacement of 600 thousand tons of standard fuel.

Geothermal energy uses resources at temperatures from 40-107 0 C and mineralization from 1.5-27 g/l located in Northern Dagestan. Over the past 40 years, 12 large thermal waters have been discovered and 130 wells have been drilled and prepared for production in the region.

However, only 15% of the potential known thermal water reserves are currently being used.

The Krasnodar region also has significant reserves of geothermal energy. The area has wide experience use of geothermal energy sources. About 50 wells are in operation, which receive water in a volume of up to 10 million m3 with a temperature of 75 to 110 °C. Wide areas of energy use in the Krasnodar Territory will make it possible to provide up to 10% of the demand for all heat and up to 3% of all energy needs in the region by 2020. In total, the thermal power of the fields in operation is 238 MW.

Central Russia and Siberia

The economic feasibility of using geothermal resources for heat and electricity generation becomes more obvious if the resources are generally available at temperatures ranging from 30 to 80 0 C (sometimes even up to 100 0 C) at depths of 1-2 km. Such resources are located in the central part of the Central Russian basin (Moscow syneclise (section)), which includes 8 districts: Vologda, Ivanovo, Kostroma, Moscow, Nizhny Novgorod,

Novgorod, Tver and Yaroslavl. There are also promising opportunities for effective use thermal waters in the Leningrad region and especially in the Kaliningrad region. The efficiency of their use can be ensured through the use of heat pumps and binary circulation systems. Widespread use of geothermal energy is possible in the center of the European part of Russia.

Siberia also has heat reserves from its subsoil, which can be used for heat supply and agriculture. The thermal waters of the platform of Western Siberia have a large artesian basin over an area of almost 3 million km 2. At depths of up to 3 km there are thermal resources of water with temperatures from 35 to 75 0 C and mineralization from 1 to 25 g/kg and are estimated at 180 m 3 /sec.

The high salinity of these thermal waters requires their reinjection after using up the thermal potential to prevent environmental pollution.

Using even 5% of its reserves will allow producing 834 million Gcal/year, which will save 119 million tons of standard fuel.

There are many thermal springs on Baikal and the surrounding area, the energy of which can reach many thousands cubic meters per day with a temperature from 30 to 80 0 C and above. Typically, the mineralization of such waters does not exceed 0.6 g/l.

If we consider chemical composition thermal waters, they mainly have alkaline reaction, sodium sulfate or bicarbonate. Most of these resources are located in the Tunkin and Barguzin cavities and along the coast of Lake Baikal.

Kamchatka and Kuril Islands

The Kuril Islands are mainly powered by diesel electricity generators and heated by boiler houses burning imported coal. At the same time, the Kuril Islands are rich in geothermal energy. Their capacity is expected to reach 300 MW. Geothermal energy required power can be implemented in close proximity to every major settlement, existing or planned objects of the Kuril Islands - on Kunashir, Iturup, Paramushir Islands, etc.

Several sources of geothermal energy on the mentioned islands have been studied. For example, on Kunashir Island, according to geological exploration data, geothermal reserves are expected to be estimated at 52 MW. The expected reserves of the northernmost island of the Kuril ridge - Paramushir, calculated using various methods, can support the operation of geothermal power plants with a capacity of 15 - 100 MW.

Direct use of geothermal resources is mainly developed in the Kuril-Kamchatka region, Dagestan and Krasnodar Territory, and primarily for heat supply and heating of greenhouses. The development of geothermal resources is quite promising in regions such as Western Siberia, Baikal, Chukotka, Primorye, Sakhalin.

Economic feasibility of using geothermal resources with water temperatures between 30 and 80/even 100ºС at depths of 1-2 km.

Natural resources of Russia

Russia, unlike many other countries, has unique natural resources.

Fossil fuel reserves are huge in Russia, and compared to the world they are: 35% for gas, 33% for wood, 12% for oil, but at the same time they have a huge amount of hot water from the earth - heat from the subsoil.

The potential energy is 8-12 times higher than the energy potential of hydrocarbon fuels, which can radically change the energy balance.

Summarizing the situation with the use of geothermal energy in Russia, first of all, it should be noted once again that three geothermal power plants are successfully operating in Kamchatka: 12 MW and 50 MW (Verkhne-Mutnovskaya and Mutnovskaya) and 11 MW in the Pauzhetskaya region. On the Kuril Islands (Kunashir and Iturup) there are two small geothermal power plants with a capacity of 3.6 MW, which also operate successfully.

Geothermal energy is one of the types of renewable energy sources (RES). The history of the use of geothermal energy for balneotherapy begins with ancient Rome, for generating electrical energy - with late XIX century (city of Lorderollo, Italy). According to the World Geothermal Congress, by 2010, geothermal power plants with a total installed capacity of 10.7 GW and geothermal heat supply systems with a total thermal capacity of more than 50.6 GW were in operation in the world.

This type of renewable energy sources is practically inexhaustible; a fraction of a percent of the heat of the earth’s interior is enough to meet all the energy needs of mankind. for a long time. The source of geothermal energy is the magmatic heat of the Earth. Geothermal deposits are localized with zones of geological movement of layers earth's crust and associated volcanic processes. In these areas of the earth's surface, magmatic flows rise close to the surface and heat the overlying sedimentary water-saturated rocks.

For the emergence of a geothermal deposit, three main conditions are necessary: the supply of deep heat, the presence of water-saturated rocks and aquitards above them. Atmospheric precipitation in mountainous areas, where rocks are exposed, penetrates them and moves towards their slope with a decrease in depth, where they are heated by magmatic heat. Geothermal coolant from the well is supplied to a geothermal power plant (GeoPP) and then ends up in another well.

In international practice, a distinction is made between surface geothermy (up to 400 m) and deep geothermy. Surface geothermy uses heat groundwater and rocks with the installation of borehole umbrellas and tubular fields buried below the freezing depth. The article discusses the issues of geothermal wells with depths from 1500 to 4000 m with the extraction of geothermal coolant in liquid or vapor state.

According to the classification of the International Energy Agency (IEA), there are five types of geothermal deposits: dry steam, wet steam, geothermal water, dry hot rocks, magma. The resources of Russia's geothermal deposits provide good prospects for the development of electricity and heat supply. According to Dr.Sc. Professor P.P. Bezrukikh, their gross potential is 22.9 trillion t.e., technical potential - 11.87 trillion t.e., economic potential - 114.9 million t.e.

In total, 3,000 geothermal wells with a depth of 2.5-3.5 km have been drilled in Russia. In Fig. 1 shows the capacity values of geothermal heat supply systems in Russian regions in 2003; in Fig. 2 - power values of individual technologies for using geothermal waters. According to Dr.Sc. Professor O.A. Povarov, the total capacity of existing geothermal heat supply systems is up to 430 MW, promising up to 21 GW.

In some regions, their use can provide up to 10% of total energy consumption. Currently, thermal water intakes are operated mainly in three regions: Dagestan, Krasnodar Territory, and the Kamchatka Peninsula. In 1984, the enterprises of OJSC Podzemburgaz (Moscow) had about 250 geothermal wells up to 3 km deep.

Of all types of geothermal resources according to the IEC classification in Russia, there are deposits of wet steam (Kamchatka, Kuril Islands), geothermal water (Kamchatka, Kuril Islands, North Caucasus), and dry hot rocks. From explored deposits - most of contains geothermal water with a temperature on the earth's surface of 70-110 °C.

During the existence of the USSR, geothermal waters were used in the Krasnodar and Stavropol territories, Kabardino-Balkaria, North Ossetia, Checheno-Ingushetia, Dagestan, Kamchatka region, Crimea, Georgia, Azerbaijan and Kazakhstan. In 1988, 60.8 million m3 of geothermal water was extracted (in the Krasnodar, Stavropol Territories, Kabardino-Balkaria, Kamchatka Region).

In the USSR there was a system of exploration, development and exploitation of geothermal resources. The VSEGINGEO Institute developed an atlas of geothermal resources of the USSR with 47 deposits with geothermal water reserves of 240-1000 m3/day. and steam-hydrotherms with reserves of more than 105-103 m3/day. Based on it, NPO Soyuzburgeothermiya (Makhachkala) developed a scheme for the country’s promising geothermal heat supply.

In the USSR, research work on this problem was carried out by institutes of the Academy of Sciences, ministries of geology and gas industry. The functions of the leading research organizations were assigned: on the problems of geothermal power plants - to the Energy Institute named after. G.M. Krzhizhanovsky (Moscow), on problems of geothermal heat supply - at the Central Scientific Research Institute engineering equipment(Moscow), but operational problems are addressed to the Academy utilities(Moscow).

The development of fields, their development and operation, and the solution of all problems (cleaning, reinjection) were carried out by divisions of the Ministry of Gas Industry. It included five regional operational departments and the Soyuzgeotherm research and production association (Makhachkala).

The operation of geothermal heating and hot water supply systems for buildings was entrusted to the USSR State Construction Committee. In the USSR, the first regulatory document on geothermy VSN 36-77 “Instructions for the integrated use of geothermal waters for heat supply to buildings and structures” was developed in 1977. In 1987, at the TsNIIEP Engineering Equipment Institute, under the leadership of Ph.D. IN AND. Krasikov developed design standards “Geothermal heat supply for residential and public buildings and structures", VSN 56-87.

Currently, geothermal resources are practically used in three regions of the country: Kamchatka and the Kuril Islands, Krasnodar Territory and Dagestan. The total capacity of GeoPPs in Kamchatka and the Kuril Islands is 84.6 MW, including the largest in Russia Mutnovskaya GeoPP with a capacity of 50 MW. Geothermal deposits with water coolant are much more common.

In the Krasnodar Territory and Adygea, 18 geothermal water deposits have been explored, including 13 that are being exploited, and five that are idle without consumers. A total of 86 geothermal wells have been drilled in this region, of which 40 are in operation. According to 1986 data in Fig. Figure 3 shows the structure of geothermal water production in the fields of the Krasnodar Territory with a total volume of 8.5 million m3, in Fig. 4 - structure of their consumption for heating greenhouses with a total volume of 4.6 million m3, in Fig. 5 - structure of consumption for heating and hot water supply of facilities with a total volume of 3.9 million m3.

In Fig. Figure 6 shows a graph of geothermal water production in the Krasnodar region with a decrease of almost three times compared to the Soviet period. Potential thermal power and thermal energy production of geothermal deposits in the Krasnodar Territory and Adygea are presented in Fig. 7. The first stage of the Geothermal Heating Demonstration Project with a capacity of 5 MW has been implemented in this region.

123 wells were drilled in Dagestan, of which 58 wells were operated at eight water intakes. The maximum amount of geothermal water was produced in 1988 - 9.4 million m3. Currently, 4.1 million m3 of geothermal water is produced annually in this region. Most large deposit Dagestan is Kizlyarskoye, where 1.4 million m3 of geothermal water is produced annually from nine wells.

This field is successfully reinjecting two wells in the amount of 0.8 million m3 per year of waste geothermal coolant, which is 57% of the total volume of produced water. Heat supply systems are double-circuit. In the first circuit, the heating fluid is water from the so-called “Chokrak” horizon with a temperature of 115 °C, in the second circuit it is water from the Absheron horizon with a temperature of 48 °C.

With a population of 45 thousand people in the city of Kizlyar, 70% of the residents are provided with geothermal heating and hot water supply. There is a project to increase the capacity of this geothermal system based on meeting 100% of the city’s needs with the reinjection of all waste coolant. The cost of implementing this project is about $1 million. The payback period is seven years.

In Makhachkala, six geothermal wells with a total flow rate of 13.6 thousand m3/day are used for hot water supply to multi-storey residential buildings. at a temperature of 95-100 °C. The city's geothermal thermal water intake has a capacity of about one million m3/year with a storage tank with a capacity of 4000 m3. In Russia, with large reserves of geothermal resources, their practical use is limited.

There is no government policy in geothermal energy. Regulatory documents are outdated, new technologies have limited application.

Geothermal resources

The surface of the planet is usually divided into three geothermal regions: hyperthermal, semithermal and normal. A hyperthermal region, with a temperature gradient of more than 80 o C/km, is most preferable for the construction of geothermal power stations. The semi-thermal region has a temperature gradient from 40 to 80 o C/km. The quality of geothermal energy is usually low, and it is better to use it directly to supply heat to buildings and other structures. A normal thermal area with a temperature gradient of less than 40 o C/km is considered unpromising for using the Earth's heat. Such areas occupy the most extensive territory; the heat flow averages 0.06 W/m2.

All sources of geothermal energy are divided into petrothermal and hydrothermal. Petrothermal springs are found in those areas of the earth's crust where there is no water. At a depth of more than 3 km, the temperature is quite high. By driving water into such a source one well at a time, steam can be obtained from another. The use of the “dry” heat of the Earth is based on this principle.

Hydrothermal springs, in turn, are divided into water, steam-water and steam. Water sources lie at different depths. One of the main conditions for their existence is the presence of an impenetrable layer of rock above the water. Being under high pressure, water can heat up to a temperature above 100 o C and exit to the surface of the earth in the form of a steam-water mixture.

In steam-water and steam deposits, aquifers are located between two waterproof layers. The lower one transfers heat from the Earth's core, and the upper one prevents it from reaching the surface of the earth. In such places, water turns into steam, and at high pressure - into superheated water. Extracting steam to the surface of the earth is only possible through drilling.

Geothermal resources have been explored in many countries around the world: the USA, Italy, Iceland, New Zealand, Russia, the Philippines, etc. The identified reserves of geothermal waters in Russia can provide approximately 14 million m 3 of hot water per day, which is equivalent to 30 million tons of equivalent fuel. At the same time, 5% of the geothermal water reserves brought to the earth's surface are used. In our country, geothermal water deposits are exploited in Sakhalin, Kamchatka and the Kuril Islands, in the Krasnodar and Stavropol Territories, Dagestan, and Ingushetia. The Kuril-Kamchatka zone of young volcanism is distinguished by the maximum proximity of geothermal systems to the earth's surface. The largest and most promising field in Kamchatka is the Mutnovskoye field, located 130 km from Petropavlovsk-Kamchatsky. Drilling work has been going on here since 1978. To date, about 90 wells have been drilled with depths ranging from 250 to 2500 m. Total reserves are estimated at 245 MW.

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TEST

on the topic: “Geothermal resources”

1. Concept and classification of geothermal resources

2. Stages and stages of geological study of subsoil

3. Principles and methods for studying and assessing geothermal resources

4. Geothermal station in Belarus

Conclusion

Bibliography

subsoil geothermal resource station

1. Concept and classidentification of geothermal resources

Geothermal energy is the production of electricity, as well as thermal energy, using the energy contained in the bowels of the earth.

The advantage of geothermal energy is its almost complete safety for environment. The amount of CO2 released during the production of 1 kW of electricity from high-temperature geothermal sources ranges from 13 to 380 g (for example, for coal it is 1042 g per 1 kW/h).

According to the classification of the International Energy Agency, geothermal energy sources are divided into 5 types:

Geothermal dry steam deposits are relatively easy to develop, but quite rare; however, half of all geothermal power plants operating in the world use heat from these sources;

Sources of wet steam (mixtures of hot water and steam) are more common, but when developing them, it is necessary to solve the issues of preventing corrosion of geothermal power plant equipment and environmental pollution (removal of condensate due to its high degree of salinity);

Geothermal water deposits (contain hot water or steam and water) are so-called geothermal reservoirs, which are formed as a result of filling underground cavities with precipitation water heated by nearby magma;

Dry hot rocks heated by magma (at a depth of 2 km or more) - their energy reserves are the greatest;

Magma, which is molten rock heated to 1300 °C.

The experience accumulated by various countries relates mainly to the use of natural steam and thermal waters, which remain the most realistic base for geothermal energy. However, its large-scale development in the future is possible only with the development of petrogeothermal resources, i.e. thermal energy of hot rocks, the temperature of which at a depth of 3-5 km usually exceeds 100 °C.

When compared with traditional energy sources, the following advantages of geothermal resources are obvious: inexhaustibility, ubiquity, proximity to the consumer, local supply of heat and electricity to the consumer, belonging to local resources, full automation, safety and practical unpopulation of geothermal energy production, economic competitiveness, the possibility of building low-power installations, environmental cleanliness.

However, the specificity of geothermal resources also includes a number of disadvantages: low temperature potential of the coolant, non-transportability, storage difficulties, dispersed sources, limited industrial experience.

Currently, it is customary to distinguish 2 main classes of geothermal resources - hydro- and petrogeothermal. The former represent that part of geothermal energy resources that is confined to natural reservoirs and is represented by natural coolants: groundwater, steam or steam-water mixtures. They are industrially operated by circulation systems (France, USA, Germany, Denmark, Ukraine, Poland, Switzerland, Russia, etc.). Petrogeothermal - that part of the thermal energy of the subsoil that is associated directly with the skeleton of water-bearing rocks or with practically impenetrable rocks. The technology for extracting petrogeothermal resources (drilling depth up to 10 km) is at an experimental level. Only a few experimental circulation systems with artificial collectors have been created in the USA, England, Japan, Russia (Tyrnyauz), Germany, and France.

Operating reserves (resources) of hydrogeothermal energy generally mean the amounts of heat and water that can be obtained from the assessed aquifer (complex) by water intake structures that are rational in technical, economic and environmental terms under a given mode of operation and the corresponding quality of the coolant (temperature, chemical and gas composition) throughout the entire design life. Operating heat reserves are expressed either in units of power or in tons of fuel (conventional) per year; operational reserves of thermal water have the dimension of volumetric flow rate for water (l/s, m3/day) or weight flow rate for steam and steam-water mixtures (kg/ s, t/day).

Most full classification resources and reserves of geothermal energy was developed by E. I. Boguslavsky.

It is advisable to take 20° C as the lower limit of thermal water temperature, taking into account possible application heat pumps and availability in many industries National economy needs for subthermal coolants with temperatures of 20-40º C.

Low-potential waters (with a temperature of 20-100°C), within which it is advisable to distinguish a subclass of waters with temperatures of 20-40°C. These waters can be consumed for heating needs, mainly using heat pumps. They can also be effectively used for thawing frozen rocks and washing placers, intensifying fishing, heating open ground, injection into oil-bearing formations, technological processes, requiring low-potential coolants. The main purpose is heat supply for industrial, agricultural and municipal facilities.

Medium-potential (100-150º C) water can be effectively used both for heat supply to industrial, agricultural and municipal facilities, and for generating electricity using intermediate working fluids.

High-potential (more than 150º C) water can be effectively used to generate electricity in a direct cycle. In the composition of such waters, it is advisable to distinguish overheated waters (150-250°C), highly overheated (250-350°C) and extremely overheated (more than 350°C).

The quality of thermal waters intended for medicinal use (in terms of temperature, salinity, ionic and gas composition, gas saturation, content of pharmacologically active microelements in water, radioactivity, pH) should be assessed in accordance with special requirements to the study and classification of mineral medicinal waters.

2. Stages and stages of studying geothermal resources of the subsoil

Sources of geothermal subsoil resources are:

Underground geothermal waters;

The heat of the mountain massif.

Geothermal resources of the subsoil can be used for:

Receiving electricity;

Hot water supply;

Heat supply for residential and industrial premises;

Medical, recreational and other purposes determined by the value, usefulness and other characteristics of geothermal resources of the subsoil.

1) Regional geological study of the subsoil is carried out in the following stages:

Small-scale geological survey work;

Medium-scale geological survey work;

Large-scale geological survey work.

2) The search for geothermal resources of the subsoil and the assessment of the deposit are carried out in order to identify and preliminary assess the deposit suitable for development. The search for geothermal resources of the subsoil and the assessment of the deposit are carried out in the following stages: - prospecting work; - assessment of the deposit.

3) Exploration of geothermal subsoil resources and preparation of the deposit for development are carried out in order to obtain information about the phenomena and processes occurring in the subsoil, the geological structure of the deposit, technological and other features of the deposit, the quality and quantity of geothermal subsoil resources located in it, and the conditions for development of the deposit , allowing for a geological and economic assessment of this deposit. Exploration of subsoil geothermal resources and preparation of the field for development is carried out in the following stages:

Preliminary exploration of geothermal subsoil resources, carried out in order to obtain reliable data for a preliminary assessment of the quality and quantity of identified reserves of geothermal subsoil resources, obtaining an economically feasible industrial assessment of the deposit, justifying the feasibility of financing further geological exploration work;

Detailed exploration of geothermal resources of the subsoil, carried out in order to prepare a field for development. Based on the results of detailed exploration of subsoil geothermal resources, permanent exploration standards for subsoil geothermal resources are developed, according to which reserves of subsoil geothermal resources are calculated;

Additional exploration of geothermal resources of the subsoil, carried out in a field that has been explored in detail, but not transferred for development in case of insufficient exploration of this field, as well as in a developed field if additional study is necessary in connection with a revision of the volumes and technology of production, primary processing (purification, enrichment) use geothermal resources of the subsoil;

Operational exploration of geothermal subsoil resources, carried out during the development of a deposit to clarify the quantity and quality of reserves of geothermal subsoil resources, obtaining other geological information necessary for drawing up annual mining development plans.

3. Principles and methods of studyand geothermal resource assessments

An important goal in the cycle of widely involving hydrogeothermal resources in the country’s fuel and energy balance is to increase the efficiency of prospecting and exploration work, which, in turn, is possible subject to constant improvement of the principles and methodological foundations of their planning and implementation. The methodology for planning prospecting and exploration work for thermal waters, as well as for other types of minerals, should be based on the fundamental principle of environmental and economic feasibility. Its effective implementation is possible if the leading general principles study of deposits: completeness of research, sequential approximation, equal reliability, minimization of socially necessary labor, material and time costs.

One of the most important is the requirement of staged exploration work, which allows, with a minimum of socially necessary costs, to carry out a stage-by-stage geological and economic assessment of deposits and areas.

The ultimate goal of the entire research cycle is the discovery, geological, economic and environmental assessment of natural coolant deposits, i.e. establishing the value of their operational reserves and thermal energy potential, as well as assessing the conditions and integrated technical and economic indicators for the development of productive aquifers, complexes or fractured zones.

When studying geothermal resources, a fairly wide range of methods is used, which is determined in each specific case the complexity and characteristics of the object being studied and the degree of its study in the previous period.

In general, the main types of field work are: geological and hydrological surveys, special surveys (geothermal, gas-hydrochemical, etc.), reconnaissance survey of the exploration area, drilling and thermohydrodynamic studies of wells, geophysical and hydrological work, stationary observations of the natural and disturbed regimes of thermal and cold waters, inspection of previously drilled deep wells and existing water intake structures, sampling of water and core material, special types research (geophysical, hydrogeochemical, geothermal, isotope, nuclear physical, etc.).

Geological and hydrogeological surveys, depending on the size and complexity of the objects being studied, are carried out on a scale of 1:50,000 - 1:10,000 (in some cases 1:5000), mainly when searching for deposits of the fissure-vein type. The purpose of the survey is to study the geological structure, geothermal and hydrogeological conditions of the field and adjacent areas, and delineate the most productive areas. Particular attention should be paid to studying the conditions for the discharge of thermal and cold waters, steam-gas jets, heated areas and zones of altered rocks, as well as identifying zones of tectonic disturbances.

Special surveys are carried out, as a rule, in combination with geological and hydrogeological surveys, or as independent species work at the exploration stage (usually when geological and hydrogeological surveys were carried out earlier). The objectives of these surveys are to map individual (or complex) parameters that are direct or indirect search indicators (criteria): temperature, components of the chemical and isotopic composition of gases, ground and surface waters. These studies are carried out by conducting thermometric (borehole or shallow wells), aerospace (IR photography) and gas-hydrochemical surveys (testing of all steam, gas and water manifestations, sampling of subsoil gas, etc.).

Reconnaissance survey of exploration areas is carried out mainly at the beginning of exploration work (built-up area, forest cover, trafficability, availability of communications, energy supply, etc.).

Drilling operations include drilling prospecting, exploration, exploration and production, observation and (if necessary) injection wells. The main type of research in order to obtain the information necessary to assess operational coolant reserves is special experimental filtration work. The methodology for carrying out these works is determined by their purpose, the staged nature of the research, and the complexity of the hydrogeological and hydrogeothermal conditions. Experimental filtration works, according to the method of their implementation, are divided into releases carried out through the use of elastic energy of the formation (fracture zone), thermal lift (steam lift), gas lift, pumping performed using special water-lifting equipment, and injection.

Depending on the intended purpose releases (pumping) are divided into trial, experimental and pilot-operational.

Trial releases (pumpings) are carried out at the stage of exploration; in some cases - at the stages of preliminary and detailed exploration. At the exploration stage, the task of trial releases (pumping) is to obtain preliminary information about the filtration and capacitive properties of rocks, their water abundance, the quality and temperature of thermal waters, steam-water mixtures and steam.

Experimental releases (pumping) are carried out at the stages of preliminary and detailed exploration and are divided into single, cluster and group. Their tasks are: determining the calculated hydrogeological parameters of productive horizons and filtration features of fracture zones, identifying patterns of their changes in plan and section; establishing a relationship between well flow and water level decline; determination of cut-off values when estimating reserves using the hydraulic method, etc.

Experimental production releases (pumping) are carried out at fissure-vein type deposits in order to obtain initial information for assessing the operational reserves of thermal waters using the hydraulic method. The main task comes down to identifying the dependence of the level decrease over time at a given design flow rate. They are carried out until stable patterns of changes in water levels and (or) quality in observation wells over time are obtained, allowing for a forecast of their depletion at the end of the estimated life of the field (site).

Before carrying out trial, experimental and pilot-operational releases (pumping out), the positions of the levels must be measured groundwater in a natural environment (or reservoir and excess pressure), water temperature at the wellhead and in reservoir conditions, and water samples are taken for general analysis.

Hydrological studies are carried out during the search and exploration of deposits of thermal waters of the fissure-vein type, which are to one degree or another connected with surface waters. In the process of research, data should be obtained on the flow regime, level, temperature and chemical regime of rivers, cold springs in the field area and in adjacent areas upstream and downstream of the waterway.

Stationary observations of the natural regime of thermal waters are carried out both at wells and at thermal water sources. They include observations of the flow regime of sources, steam-gas jets, chemical (including gas) composition and temperature. Tasks:

Clarification of the conditions for the relationship between underground thermal and surface cold waters;

Determination of seasonal and long-term changes in spring flow of thermal waters;

Study of the nature of changes in mineralization, chemical and gas composition, temperature of thermal waters in annual and long-term sections;

Determination of parameters of the relationship between thermal waters of individual fissure zones.

Observations of the disturbed regime of thermal waters in areas of operating water intake structures should include observations of water levels in operational and specially equipped observation wells, the chemical and gas composition of thermal waters, the temperature of water at the outlet and along the wellbore, and the flow rate of water intake wells.

Special research methods (hydrogeochemical, geothermal, isotope, nuclear physical) are intended to clarify the conditions for the formation of operational reserves of thermal waters, identify and localize areas of recharge and discharge, study the conditions of interaction between aquifers through separating low-permeability layers and interaction between fracture zones, as well as to study the processes of movement of injected water into formations, its cooling, etc. This also includes geobotanical studies that are carried out at the exploratory stage in fissure-vein type deposits. They consist in the study of plant communities, which are used to identify and delineate areas of heating and hidden thermal manifestations.

Geophysical methods. When studying thermal water deposits, almost all types of geophysical methods are used: borehole, ground, aerographic, etc. With their help, it is clarified geological structure study area (especially deep), hydrogeological stratification and correlation of sections are carried out, hydrogeodynamic, hydrogeochemical and hydrogeothermal characteristics of the studied strata are studied.

Ground, aquatic (sea) and aerographic methods provide an almost complete study of the territory. They include electrical, seismic, gravitational-magnetic prospecting, radio and thermometry, most often carried out in a land-based version, but can be carried out at the bottom of reservoirs or from the water surface: these same methods, with the exception of seismic prospecting, are implemented using aircraft. Like geophysical surveys of wells (GIS), ground and aerographic work is carried out by making special field observations, or on the basis of re-interpretation of available multi-purpose materials.

Landscape-indication methods in relation to the research object are divided into ground-based and remote.

Ground-based methods are used in geothermal research to a very limited extent, only for geological reference and interpretation of anomalies identified by remote methods. At the same time, problems of the general geological-hydrogeological plan and special geothermal directions are solved.

When searching for thermal waters and other types of geological work, remote (aerospace) methods are widely used. With their help, they take pictures of the earth's surface, registering light, infrared and decimeter electromagnetic fields, i.e. having a length from 0.3 microns to 1.0 m. modern remote sensing methods are essentially a complex of methods for electrical prospecting, thermometry, and landscape science, using both the listed methods and visual observations.

When remotely studying the Earth's surface, both aerial vehicles (planes, helicopters) and space vehicles (manned spaceships, artificial earth satellites, orbital scientific stations). The height of aerial observations varies from several tens of meters to several kilometers, and space observations - from 300 to 3000 km.

Especially important In forecasting, searching and exploration of thermal waters, aerospace photography (AFS and CFS) and IR photography are used.

Aerospace photography is currently the main type of remote observation. When filming from spacecraft, a huge area is covered, measured in hundreds of thousands of square kilometers, while from aircraft - only tens of square kilometers. In general, APS and CFS make it possible to solve a series of geological and hydrogeological problems, however, this information is not always sufficient for hydrogeothermal studies.

Infrared photography is based on the ability of natural bodies to emit infrared rays. Their intensity is determined by the temperature and emissivity of these bodies. IR photography is the most important remote sensing method in geothermal research, especially when studying volcanism and hydrothermal activity occurring in the near-surface part of the section. In conditions of haze and fog, IR photography has a significant advantage over AFS and CFS and allows you to obtain an image good quality. Using IR photography, you can solve a series of hydrogeological problems: assess soil moisture, determine groundwater levels, identify zones of groundwater discharge within water areas, trace tectonic faults, delineate talik zones, detect heated areas of the earth's surface, identify thermal water outlets.

4 . Ggeothermal station in Belarus

In the republic, two territories were discovered in the Gomel and Brest regions with reserves of geothermal water with a density of more than 2 tons conventional. t./mI and a temperature of 50°C at a depth of 1.4-1.8 km and 90-100°C at a depth of 3.8-4.2 km. But temperature conditions The subsoil of the republic's territory has not been sufficiently studied. The great depth of thermal waters, their relatively low temperature, high salinity and low flow rate of wells (100-1150 cubic meters/day) do not currently allow us to consider the thermal waters of the republic as a noteworthy source of energy.

In February 2010, the Brest enterprise launched the first geothermal station in Belarus.

The work of the country's first geothermal station has begun. The pilot project was carried out by the Berestye greenhouse complex. In fact, this is a new word in the use of alternative energy sources.

A well was drilled on the territory of the plant to a depth of 1520 meters, where the water temperature exceeds 40 degrees. True, the volume of the source turned out to be small. In progress further work It was found that at a depth of 1000-1100 meters there are very thick layers of water quite warm, about 30 degrees, suitable for industrial use. It's unsalted High Quality. The next stage was the purchase of heat pumps and other special equipment.

A geothermal station is an electronic-mechanical system that allows, relatively speaking, from 1000 liters of water at a temperature of 30 degrees, to obtain, for example, 300 liters of water with a temperature of 65 degrees and 700 liters with a temperature of 4 degrees. hot the water is flowing for heating greenhouses. And cold water, according to the project, will be purified and supplied to the city’s drinking network in the amount of one and a half thousand tons per day. It will be bottled and sold.

The system currently provides 1.5 hectares of greenhouses and is linked to a common cycle with the boiler system. Natural heat is distributed to part of the area occupied by flowers, salad line, cucumbers and tomatoes. It is made so that if the air temperature drops sharply, the central boiler room will immediately connect. According to calculations, 1 million cubic meters of gas will be replaced per year, which will save more than 200 thousand dollars. For example, the saved fuel can heat more than one and a half hundred two-story cottages. The power of the station is one gigacalorie per hour. The station produces more heat than designed according to the design.

The entire control system operates in automatic mode, and all necessary parameters are displayed on a monitor in the central boiler room.

The main difficulty was and still remains that there are practically no specialists in the design and adjustment of such systems.

The well was drilled by Belgeology to search for oil, gas and other minerals. The work was financed by the Ministry of Natural Resources and Environmental Protection of the Republic of Belarus. Two powerful heat pumps cost about 100 thousand euros. Helped the regional executive committee, used own funds. By by and large, the project was inexpensive. In addition, it should pay for itself in 5 years.

If water is pumped out from the depths, then in no case is a vacuum created there. Sand layers saturated with water are constantly renewed. And heating occurs due to the temperature of the earth.

Conclusion

Geothermal resources - the amount of heat contained in the lithosphere or its sections, to a depth technically achievable by drilling means for the forecast period.

The main stages of studying geothermal resources of the subsoil are:

Regional geological study of subsoil;

Search for geothermal subsoil resources and field assessment;

Exploration of geothermal subsurface resources (including trial exploitation of hydrocarbon deposits or individual drilling wells), preparation of the field for development.

The main types of field work are: geological and hydrological surveys, special surveys (geothermal, gas-hydrochemical, etc.), reconnaissance survey of the exploration area, drilling and thermohydrodynamic studies of wells, geophysical and hydrological work, stationary observations of the natural and disturbed regimes of thermal and cold waters, examination of previously drilled deep wells and existing water intake structures, sampling of water and core material, special types of research (geophysical, hydrogeochemical, geothermal, isotope, nuclear physical, etc.).

The temperature conditions of the subsoil of the territory of the Republic of Belarus have not been sufficiently studied. The great depth of thermal waters, their relatively low temperature, high salinity and low flow rate of wells (100-1150 cubic meters/day) do not currently allow us to consider the thermal waters of the republic as a noteworthy source of energy.

Bibliography

1. A.A. Shpak, I.M. Melkanovitsky, A.I. Serezhnikov “Methods for studying and assessing geothermal resources.” M.: Nedra, 1992. - 316 p.

3. www.baltfriends.ru

4. www.news.tut.by

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