The principle of operation of gas turbine plants
Fig.1. Scheme of a gas turbine unit with a single-shaft gas turbine engine of a simple cycle
Clean air is supplied to the compressor (1) of the gas turbine power unit. Under high pressure, air from the compressor is sent to the combustion chamber (2), where the main fuel, gas, is also supplied. The mixture ignites. When a gas-air mixture is burned, energy is generated in the form of a stream of hot gases. This flow rushes at high speed to the turbine wheel (3) and rotates it. rotational kinetic energy through the turbine shaft drives the compressor and electric generator (4). From the terminals of the power generator, the generated electricity, usually through a transformer, is sent to the power grid, to energy consumers.
Gas turbines are described by the Brayton thermodynamic cycle. The Brayton/Joule cycle is a thermodynamic cycle that describes the working processes of gas turbine, turbojet and ramjet internal combustion engines, as well as gas turbine external combustion engines with a closed loop of a gaseous (single-phase) working fluid.
The cycle is named after American engineer George Brighton, who invented the reciprocating internal combustion engine that operated on this cycle.
Sometimes this cycle is also called the Joule cycle - in honor of the English physicist James Joule, who established the mechanical equivalent of heat.
Fig.2. P,V diagram Brighton cycle
The ideal Brayton cycle consists of the processes:
- 1-2 Isentropic compression.
- 2-3 Isobaric heat input.
- 3-4 Isentropic expansion.
- 4-1 Isobaric heat removal.
Taking into account the differences between real adiabatic processes of expansion and contraction from isentropic ones, a real Brayton cycle is constructed (1-2p-3-4p-1 on the T-S diagram) (Fig. 3)
Fig.3. T-S chart Brighton cycle
Ideal (1-2-3-4-1)
Real (1-2p-3-4p-1)
The thermal efficiency of an ideal Brayton cycle is usually expressed by the formula:
- where P = p2 / p1 - the degree of pressure increase in the process of isentropic compression (1-2);
- k - adiabatic index (for air equal to 1.4)
It should be especially noted that this generally accepted way of calculating the cycle efficiency obscures the essence of the ongoing process. The limiting efficiency of the thermodynamic cycle is calculated through the temperature ratio using the Carnot formula:
- where T1 is the refrigerator temperature;
- T2 - heater temperature.
Exactly the same temperature ratio can be expressed in terms of the pressure ratios used in the cycle and the adiabatic index:
Thus, the efficiency of the Brayton cycle depends on the initial and final temperatures of the cycle in exactly the same way as the efficiency of the Carnot cycle. With an infinitesimal heating of the working fluid along the line (2-3), the process can be considered isothermal and completely equivalent to the Carnot cycle. The amount of heating of the working fluid T3 in the isobaric process determines the amount of work related to the amount of the working fluid used in the cycle, but in no way affects the thermal efficiency of the cycle. However, in the practical implementation of the cycle, heating is usually carried out to the highest possible values limited by the heat resistance of the materials used in order to minimize the size of the mechanisms that compress and expand the working fluid.
In practice, friction and turbulence cause:
- Non-adiabatic compression: for a given total pressure ratio, the compressor discharge temperature is higher than ideal.
- Non-adiabatic expansion: although the temperature of the turbine drops to the level necessary for operation, the compressor is not affected, the pressure ratio is higher, as a result, the expansion is not enough to provide useful work.
- Pressure losses in the air intake, combustion chamber and outlet: as a result, the expansion is not sufficient to provide useful work.
As with all cyclic heat engines, the higher the combustion temperature, the higher the efficiency. The limiting factor is the ability of the steel, nickel, ceramic or other materials that make up the engine to withstand heat and pressure. Much of the engineering work is focused on removing heat from parts of the turbine. Most turbines also try to recover heat from exhaust gases that are otherwise wasted.
Recuperators are heat exchangers that transfer heat from exhaust gases to compressed air before combustion. In a combined cycle, heat is transferred to the steam turbine systems. And in combined heat and power (CHP), waste heat is used to produce hot water.
Mechanically, gas turbines can be considerably simpler than reciprocating internal combustion engines. Simple turbines may have one moving part: shaft/compressor/turbine/alternate rotor assembly (see image below), not including the fuel system.
Fig.4. This machine has a single stage radial compressor,
turbine, recuperator, and air bearings.
More complex turbines (those used in modern jet engines) may have multiple shafts (coils), hundreds of turbine blades, moving stator blades, and an extensive system of complex piping, combustion chambers, and heat exchangers.
As a general rule, the smaller the motor, the higher the speed of the shaft(s) required to maintain the maximum linear speed of the blades.
The maximum speed of the turbine blades determines the maximum pressure that can be reached, resulting in maximum power regardless of engine size. Jet engine rotates at a frequency of about 10,000 rpm and a micro-turbine - at a frequency of about 100,000 rpm.
The development of new types of gas turbines, the growing demand for gas compared to other types of fuel, large-scale plans of industrial consumers to create their own capacities cause a growing interest in gas turbine construction.
R The small generation market has great development prospects. Experts predict an increase in demand for distributed energy from 8% (currently) to 20% (by 2020). This trend is explained by the relatively low tariff for electricity (2-3 times lower than the tariff for electricity from the centralized network). In addition, according to Maxim Zagornov, a member of the General Council, “ Business Russia”, President of the Association of Small-Scale Energy of the Urals, Director of the MKS Group of Companies, small generation is more reliable than the network: in the event of an accident on the external network, the supply of electricity does not stop. Additional advantage decentralized energy - commissioning speed: 8-10 months as opposed to 2-3 years for the creation and connection of network lines.
Denis Cherepanov, co-chairman of the Delovaya Rossiya committee on energy, claims that the future belongs to its own generation. According to the First Deputy Chairman of the Committee State Duma on Energy by Sergey Yesyakov, in the case of distributed energy in the chain "energy - consumer", it is the consumer, and not the energy sector, that is the decisive link. With its own generation of electricity, the consumer declares the necessary capacities, configurations and even the type of fuel, saving, at the same time, on the price of a kilowatt of energy received. Among other things, experts believe that additional savings can be obtained if the power plant is operated in cogeneration mode: thermal energy goes to heating. Then the payback period of the generating power plant will be significantly reduced.
The most actively developing area of distributed energy is the construction of low-capacity gas turbine power plants. Gas turbine power plants are designed for operation in any climatic conditions as the main or backup source of electricity and heat for industrial and domestic facilities. The use of such power plants in remote areas allows you to get significant savings by eliminating the costs of building and operating long power lines, and in central areas - to increase the reliability of electrical and heat supply to both individual enterprises and organizations, and territories as a whole. Consider some gas turbines and gas turbine units that are offered by well-known manufacturers for the construction of gas turbine power plants in the Russian market.
General Electric
GE's wind turbine solutions are highly reliable and suitable for applications in a wide range of industries, from oil and gas to utilities. In particular, GE gas turbine units of the LM2500 family with a capacity of 21 to 33 MW and an efficiency of up to 39% are actively used in small generation. The LM2500 is used as a mechanical drive and a power generator drive, they work in power plants in simple, combined cycle, cogeneration mode, offshore platforms and pipelines.
For the past 40 years, GE turbines of this series have been the best-selling turbines in their class. In total, more than 2,000 turbines of this model have been installed in the world with a total operating time of more than 75 million hours.
Key features of the LM2500 turbines: lightweight and compact design for quick installation and easy maintenance; reaching full power from the moment of launch in 10 minutes; high efficiency (in a simple cycle), reliability and availability in its class; the possibility of using dual-fuel combustion chambers for distillate and natural gas; the possibility of using kerosene, propane, coke oven gas, ethanol and LNG as fuel; low NOx emissions using DLE or SAC combustion chambers; reliability factor - more than 99%; readiness factor - more than 98%; NOx emissions - 15 ppm (DLE modification).
To provide customers with reliable support throughout the life cycle of generating equipment, GE opened a specialized Energy Technology Center in Kaluga. It offers customers modern solutions for maintenance, inspection and repair of gas turbines. The company has implemented a quality management system in accordance with ISO standard 9001.
Kawasaki Heavy Industries
Japanese company Kawasaki Heavy Industries, Ltd. (KHI) is a diversified engineering company. important place in her production program occupied by gas turbines.
In 1943, Kawasaki created Japan's first gas turbine engine and is now one of the world's recognized leaders in the production of gas turbines of small and medium power, having accumulated references for more than 11,000 installations.
With environmental friendliness and efficiency as a priority, the company has made great strides in the development of gas turbine technologies and is actively pursuing promising developments, including in the field of new energy sources as an alternative to fossil fuels.
Having good experience in cryogenic technologies, technologies for the production, storage and transportation of liquefied gases, Kawasaki is actively researching and developing in the field of using hydrogen as a fuel.
In particular, the company already has prototypes of turbines that use hydrogen as an additive to methane fuel. In the future, turbines are expected, for which, much more energy-efficient and absolutely environmentally friendly, hydrogen will replace hydrocarbons.
GTU Kawasaki GPB series are designed for baseload operation, including both parallel and isolated network interaction schemes, while the power range is based on machines from 1.7 to 30 MW.
IN model range there are turbines that use steam injection to suppress harmful emissions and use the DLE technology modified by the company's engineers.
Electrical efficiency, depending on the generation cycle and power, respectively, from 26.9% for GPB17 and GPB17D (M1A-17 and M1A-17D turbines) to 40.1% for GPB300D (L30A turbine). Electric power - from 1700 to 30 120 kW; thermal power - from 13,400 to 8970 kJ / kWh; exhaust gas temperature - from 521 to 470°C; exhaust gas consumption - from 29.1 to 319.4 thousand m3/h; NOx (at 15% O2) - 9/15 ppm for gas turbines M1A-17D, M7A-03D, 25 ppm for turbine M7A-02D and 15 ppm for turbines L20A and L30A.
In terms of efficiency, Kawasaki gas turbines, each in its class, are either the world leader or one of the leaders. The overall thermal efficiency of power units in cogeneration configurations reaches 86-87%. The company produces a number of GTUs in dual-fuel (natural gas and liquid fuel) versions with automatic switching. At the moment, three models of gas turbines are most in demand among Russian consumers - GPB17D, GPB80D and GPB180D.
Kawasaki gas turbines are distinguished by: high reliability and long service life; compact design, which is especially attractive when replacing equipment of existing generating facilities; ease of maintenance due to the split design of the body, removable burners, optimally located inspection holes, etc., which simplifies inspection and maintenance, including by the user's personnel;
Environmental friendliness and economy. The combustion chambers of Kawasaki turbines are designed using the most advanced methods to optimize the combustion process and achieve best performance turbine efficiency, as well as to reduce the content of NOx and other harmful substances in the exhaust. Environmental performance is also improved through the use of advanced dry emission suppression technology (DLE);
Ability to use a wide range of fuels. Natural gas, kerosene, diesel fuel, type A light fuel oils, as well as associated petroleum gas can be used;
Reliable after-sales service. High level of service, including free system online monitoring (TechnoNet) with the provision of reports and forecasts, technical support by highly qualified personnel, as well as replacement by trade-in gas turbine engine during overhaul(downtime of GTU is reduced to 2-3 weeks), etc.
In September 2011, Kawasaki introduced latest system combustion chamber, which has reduced NOx emissions to less than 10 ppm for the M7A-03 gas turbine engine, which is even lower than current regulations require. One of the company's approaches to design is to create new technology, which meets not only modern, but also future, more stringent, requirements for environmental performance.
The highly efficient 5 MW GPB50D gas turbine with a Kawasaki M5A-01D turbine uses the latest proven technologies. High efficiency installation makes it optimal for electricity and cogeneration. Also, the compact design of the GPB50D is particularly advantageous when upgrading existing plants. The rated electrical efficiency of 31.9% is the best in the world among 5 MW plants.
The M1A-17D turbine, through the use of an original combustion chamber design with dry emission suppression (DLE), has excellent environmental performance (NOx< 15 ppm) и эффективности.
The ultra-low weight of the turbine (1470 kg), the lowest in the class, is due to the widespread use of composite materials and ceramics, from which, for example, the impeller blades are made. Ceramics are more resistant to operation at elevated temperatures, less prone to contamination than metals. The gas turbine has an electrical efficiency close to 27%.
In Russia, by now, Kawasaki Heavy Industries, Ltd. in collaboration with Russian companies implemented a number of successful projects:
Mini-TPP "Central" in Vladivostok
By order of JSC "Far Eastern Energy management company(JSC DVEUK) 5 GTU GPB70D (M7A-02D) were delivered for TPP Tsentralnaya. The station provides electricity and heat to consumers in the central part of the development of Russky Island and the campus of the Far Eastern Federal University. TPP Tsentralnaya is the first power facility in Russia with Kawasaki turbines.
Mini-CHP "Oceanarium" in Vladivostok
This project was also carried out by JSC "DVEUK" for the power supply of the scientific and educational complex "Primorsky Oceanarium" located on the island. Two GPB70D gas turbines have been delivered.
GTU manufactured by Kawasaki in Gazprom PJSC
Kawasaki's Russian partner, MPP Energotechnika LLC, based on gas turbine M1A-17D produces a containerized power plant "Korvette 1.7K" for installation in open areas with an ambient temperature range of -60 to + 40 °C.
Within the framework of the cooperation agreement, developed and production facilities MPP Energotechnika assembled five EGTEPS KORVET-1.7K. Areas of responsibility of companies in this project distributed as follows: Kawasaki supplies the M1A-17D gas turbine engine and turbine control systems, Siemens AG supplies the high-voltage generator. MPP Energotechnika LLC manufactures a block container, an exhaust and air intake device, a power unit control system (including the SHUVGM excitation system), electrical equipment - main and auxiliary, completes all systems, assembles and supplies a complete power plant, and also sells APCS.
EGTES Korvet-1.7K has passed interdepartmental tests and is recommended for use at the facilities of Gazprom PJSC. The gas turbine power unit was developed by LLC MPP Energotechnika according to the terms of reference of PJSC Gazprom within the framework of the Scientific and Technical Cooperation Program of PJSC Gazprom and the Japan Natural Resources and Energy Agency.
Turbine for CCGT 10 MW at NRU MPEI
Kawasaki Heavy Industries Ltd., has manufactured and delivered a complete gas turbine plant GPB80D with a nominal power of 7.8 MW for the National Research University "MPEI" located in Moscow. CHP MPEI is a practical training and, generating electricity and heat on an industrial scale, provides them with the Moscow Power Engineering Institute itself and supplies them to the utility networks of Moscow.
Expansion of the geography of projects
Kawasaki, drawing attention to the advantages of developing local energy in the direction of distributed generation, proposed to start implementing projects using gas turbines of minimum capacity.
Mitsubishi Hitachi Power Systems
The model range of H-25 turbines is presented in the power range of 28-41 MW. Full complex turbine manufacturing work, including R&D and a remote monitoring center, is being carried out at the plant in Hitachi, Japan by MHPS (Mitsubishi Hitachi Power Systems Ltd.). Its formation falls on February 2014 due to the merger of the generating sectors of the recognized leaders in mechanical engineering Mitsubishi Heavy Industries Ltd. and Hitachi Ltd.
H-25 models are widely used around the world for both simple cycle operation due to high efficiency (34-37%), and combined cycle in 1x1 and 2x1 configuration with 51-53% efficiency. Having high temperature indicators of exhaust gases, the GTU has also successfully proven itself to operate in the cogeneration mode with a total station efficiency over 80%.
Many years of expertise in the production of gas turbines for a wide range of capacities and a well-thought-out design of a single-shaft industrial turbine distinguish the N-25 with high reliability with an equipment availability factor of more than 99%. The total operating time of the model exceeded 6.3 million hours in the second half of 2016. The modern gas turbine is made with a horizontal axial split, which ensures ease of maintenance, as well as the possibility of replacing parts of the hot path at the place of operation.
The countercurrent tubular-annular combustion chamber provides stable combustion on various types of fuel, such as natural gas, diesel fuel, liquefied petroleum gas, flue gases, coke oven gas, etc. pre-mixing of the gas-air mixture (DLN). The H-25 gas turbine engine is a 17-stage axial compressor coupled to a three-stage active turbine.
An example of reliable operation of the N-25 GTU at small generation facilities in Russia is the operation as part of a cogeneration unit for own needs JSC "Ammoniy" plant in Mendeleevsk, Republic of Tatarstan. The cogeneration unit provides the production site with 24 MW of electricity and 50 t/h of steam (390°C / 43 kg/cm3). In November 2017, the first inspection of the turbine combustion system was successfully carried out at the site, which confirmed the reliable operation of the machine components and assemblies at high temperatures.
In the oil and gas sector, N-25 GTUs were used to operate the Sakhalin II Onshore Processing Facility (OPF) site of the Sakhalin Energy Investment Company, Ltd. The OPF is located 600 km north of Yuzhno-Sakhalinsk in the landfall area offshore gas pipeline and is one of the most important facilities of the company, responsible for the preparation of gas and condensate for subsequent transmission through the pipeline to the oil export terminal and the LNG plant. The technological complex includes four H-25 gas turbines located in industrial operation Since 2008, the cogeneration unit based on the N-25 GTU has been maximally integrated into the integrated energy system of the OPF, in particular, the heat from the exhaust gases of the turbine is used to heat crude oil for the needs of oil refining.
Siemens Industrial Gas Turbine Generator Sets (hereinafter referred to as GTU) will help to cope with the difficulties of the dynamically developing market of distributed generation. Gas turbines with a unit rated power from 4 to 66 MW fully meet the high requirements in the field of industrial combined energy production, in terms of plant efficiency (up to 90%), operational reliability, service flexibility and environmental safety, ensuring low life cycle costs and high return on investment. Siemens has more than 100 years of experience in the construction of industrial gas turbines and thermal power plants based on them.
GTU "Siemens" with a capacity of 4 to 66 MW are used by small energy companies, independent manufacturers electricity (for example, industrial enterprises), as well as in oil and gas industry. The use of technologies for distributed generation of electricity with combined generation of thermal energy makes it possible to refuse from investing in multi-kilometer power lines, minimizing the distance between the energy source and the facility that consumes it, and achieve serious cost savings by covering the heating of industrial enterprises and infrastructure facilities through heat recovery. A standard Mini-TPP based on a Siemens GTU can be built anywhere where there is access to a fuel source or its prompt supply.
SGT-300 is an industrial gas turbine with a rated electric power of 7.9 MW (see Table 1), which combines a simple, reliable design with the latest technology.
Table 1. Specifications of SGT-300 for Mechanical Drive and Power Generation
|
Energy production |
mechanical drive |
||
|---|---|---|---|
|
7.9 MW |
8 MW |
9 MW |
|
|
Power in ISO |
|||
|
Natural gas / liquid fuel / dual fuel and other fuels on request; Automatic fuel change from main to reserve, at any load |
|||
|
Oud. heat consumption |
11.773 kJ/kWh |
10.265 kJ/kWh |
10.104 kJ/kWh |
|
Power turbine speed |
5.750 - 12.075 rpm |
5.750 - 12.075 rpm |
|
|
Compression ratio |
|||
|
Exhaust gas consumption |
|||
|
Exhaust gas temperature |
542°C (1.008°F) |
491°C (916°F) |
512°C (954°F) |
|
NOX emissions Gas fuel with DLE system |
|||
1) Electrical 2) Shaft mounted
Rice. 1. Structure of the SGT-300 gas generator
For industrial power generation, a single-shaft version of the SGT-300 gas turbine is used (see Fig. 1). It is ideal for the combined production of thermal and electrical energy(TPP). The SGT-300 gas turbine is an industrial gas turbine, originally designed for generation and has the following operational advantages for operating organizations:
Electrical efficiency - 31%, which is on average 2-3% higher than the efficiency of gas turbines of lower power, thanks to a higher efficiency value, economic effect on saving fuel gas;
The gas generator is equipped with a low-emission dry combustion chamber using DLE technology, which makes it possible to achieve levels of NOx and CO emissions that are more than 2.5 times lower than those established by regulatory documents;
The GTP has good dynamic characteristics due to its single-shaft design and ensures stable operation of the generator in case of fluctuations in the load of the external connected network;
The industrial design of the gas turbine provides a long overhaul life and is optimal in terms of organizing service work that is carried out at the site of operation;
A significant reduction in the building footprint, as well as investment costs, including the purchase of plant-wide mechanical and electrical equipment, its installation and commissioning, when using a solution based on SGT-300 (Fig. 2).
Rice. 2. Weight and size characteristics of the SGT-300 block
The total operating time of the installed fleet of SGT-300 is more than 6 million hours, with the operating time of the leading GTU 151 thousand hours. Availability/availability ratio - 97.3%, reliability ratio - 98.2%.
OPRA (Netherlands) is a leading supplier of energy systems based on gas turbines. OPRA develops, manufactures and markets state-of-the-art gas turbine engines around 2 MW. The key activity of the company is the production of electricity for the oil and gas industry.
The reliable OPRA OP16 engine delivers higher performance at lower cost and longer life than any other turbine in its class. The engine runs on several types of liquid and gaseous fuels. There is a modification of the combustion chamber with a reduced content of pollutants in the exhaust. The OPRA OP16 1.5-2.0 MW power plant will be a reliable assistant in harsh operating conditions.
OPRA gas turbines are the perfect equipment for power generation in off-grid electric and small-scale cogeneration systems. The design of the turbine has been under development for more than ten years. The result is a simple, reliable and efficient gas turbine engine, including a low emission model.
A distinctive feature of the technology for converting chemical energy into electrical energy in OP16 is the COFAR patented fuel mixture preparation and supply control system, which provides combustion modes with minimal formation of nitrogen and carbon oxides, as well as a minimum of unburned fuel residues. The patented geometry of the radial turbine and the generally cantilever design of the replaceable cartridge, including the shaft, bearings, centrifugal compressor and turbine, are also original.
The specialists of OPRA and MES Engineering developed the concept of creating a unique unified technical complex for waste processing. Of the 55-60 million tons of all MSW generated in Russia per year, a fifth - 11.7 million tons - falls on the capital region (3.8 million tons - the Moscow region, 7.9 million tons - Moscow). At the same time, 6.6 million tons of household waste are removed from Moscow outside the Moscow Ring Road. Thus, more than 10 million tons of garbage settle in the Moscow region. Since 2013, out of 39 landfills in the Moscow Region, 22 have been closed. incinerators. The same situation occurs in most other regions. However, the construction of large waste processing plants is not always profitable, so the problem of waste processing is very relevant.
The developed concept of a single technical complex combines fully radial OPRA units with high reliability and efficiency with the MES gasification / pyrolysis system, which allows for efficient conversion various kinds waste (including MSW, oil sludge, contaminated land, biological and medical waste, wood waste, sleepers, etc.) into an excellent fuel for generating heat and electricity. As a result of long-term cooperation, a standardized waste processing complex with a capacity of 48 tons / day has been designed and is under implementation. (Fig. 3).
Rice. 3. General layout of a standard waste processing complex with a capacity of 48 tons/day.
The complex includes a MES gasification unit with a waste storage site, two OPRA GTUs with a total electric power of 3.7 MW and a thermal power of 9 MW, as well as various auxiliary and protective systems.
The implementation of such a complex makes it possible on an area of 2 hectares to obtain an opportunity for autonomous energy and heat supply to various industrial and communal facilities, while solving the issue of recycling various types of household waste.
The differences between the developed complex and existing technologies stem from the unique combination of the proposed technologies. Small (2 t/h) volumes of consumed waste, along with a small required area of the site, allow placing this complex directly near small settlements, industrial enterprises, etc., significantly saving money on the constant transportation of waste to their disposal sites. Complete autonomy of the complex allows you to deploy it almost anywhere. The use of the developed standard project, modular structures and the maximum degree of factory readiness of the equipment makes it possible to minimize the construction time to 1-1.5 years. The use of new technologies ensures the highest environmental friendliness of the complex. The MES gasification unit simultaneously produces gas and liquid fraction fuel, and due to the dual-fuel nature of the GTU OPRA, they are used simultaneously, which increases fuel flexibility and reliability of power supply. The low demands of the OPRA GTU on fuel quality increase the reliability of the entire system. The MES unit allows the use of waste with a moisture content of up to 85%, therefore, waste drying is not required, which increases the efficiency of the entire complex. The high temperature of the exhaust gases of the OPRA GTU makes it possible to provide reliable heat supply with hot water or steam (up to 11 tons of steam per hour at 12 bar). The project is standard and scalable, which allows for the disposal of any amount of waste.
The calculations carried out show that the cost of electricity generation will be from 0.01 to 0.03 euros per 1 kWh, which shows a high economic efficiency project. Thus, the OPRA company once again confirmed its focus on expanding the range of fuels used and increasing fuel flexibility, as well as focusing on the maximum use of "green" technologies in its development.
§ 45. Turbine installations
Marine turbines are used to convert the thermal energy of steam or gas into mechanical work. The method of energy conversion in the turbine does not depend on the working fluid that is used in the turbine. Therefore, the working processes occurring in steam turbines do not differ significantly from the working processes occurring in gas turbines, and the basic design principles for steam and gas turbines are the same.Fresh steam or gas, entering the nozzle, which is the guide vane, expands, potential energy is converted into kinetic energy, and the steam or gas acquires a significant speed. Upon exiting the nozzle, steam or gas enters the channels of the working blades mounted on the rim of the turbine disk, which sits on the turbine shaft. The working fluid presses on the curved surfaces of the rotor blades, causing the disk with the shaft to rotate. The set of such guide vanes (nozzles) and rotor blades under consideration on the turbine disk is called turbine stage. Turbines with only one stage are called single stage Unlike multistage turbines.
Turbines according to the principle of operation of the working fluid (steam or gas) are divided into two main groups. Turbines in which the expansion of steam or gas occurs only in stationary guide vanes, and only their kinetic energy is used on the rotor blades are called active. Turbines in which the expansion of steam or gas also occurs during movement working fluid in the channels of the rotor blades are called reactive. Turbines rotate only in one direction and are non-reversible, i.e. they cannot change the direction of rotation. Therefore, on the same shaft with the main forward turbines, reverse turbines are usually provided. The power of ship reverse turbines does not exceed 40-50% of the power of forward turbines. Since these turbines do not have to provide high efficiency in operation, the number of stages in them is small.
Marine steam turbine plants operating at an initial steam pressure of 40–50 atm and a steam temperature of 450–480°C have an economic efficiency of 24–27%.
economic(effective) efficiency is the ratio of heat converted into useful work to the heat developed during the complete combustion of the consumed fuel. Effective efficiency characterizes the efficiency of the engine. With an increase in pressure to 70-80 atm and a steam temperature of up to 500-550 ° C, the economic efficiency increases to 29-31%. A further increase in the initial steam pressure and the improvement of installations will increase the efficiency of a marine steam turbine plant by about 35%.
Work on ship gas turbine plants (GTP) is essentially still experimental in nature, since their serial design has not yet been created.
gas turbine differs from steam in that its working fluid is not steam from boilers, but gases formed during the combustion of fuel in special chambers.
The structure and operation of a gas turbine are similar to those of a steam turbine. They can also be active or reactive, single-hull, multi-hull, etc. Gas turbines differ from steam turbines in higher temperature loads: the temperature of hot gases is in the range of 700-800 ° C. The difference in temperature reduces the resources of the gas turbine operation time.
Depending on the method of air compression and the formation of hot gases, gas turbine plants with a combustion chamber and gas turbine units with free piston gas generators(SPGG). The negative quality of gas turbines is a large loss of heat during the removal of exhaust gases.
The method of increasing the efficiency of gas turbines is the use of exhaust gas heat to heat the air entering the combustion chamber, the so-called regeneration.
The use of regeneration with simultaneous two-stage air compression increases the effective efficiency of the installation up to 28-30%. Such gas turbines are used as ship power plants.
In a ship gas turbine plant with a combustion chamber (Fig. 69), atmospheric air is sucked in, compressed by a compressor low pressure 1, located on the same shaft with the gas turbine 5, and is sent to the cooler 2, cooled by sea water. The cooled air enters the high-pressure compressor 3, where it is again compressed to a higher pressure, after which it is fed into the regenerator 4, from where it is heated by the exhaust gases and goes into the combustion chamber 6, where the fuel supplied there burns out. The combustion products expand in the gas turbine 5 and through the regenerator, having given up part of the heat to the air in it, they go out into the atmosphere or are used in a waste-heat boiler.
Rice. 69. Scheme of a gas turbine plant with regeneration and two-stage air compression.
The energy developed in the gas turbine is not fully used for its main purpose, but is partially spent on driving compressors. To start a gas turbine, it must be untwisted by starting electric motors.
A gas turbine plant with a free-piston gas generator (SPGG) is an active or jet turbine and a diesel cylinder in which fuel is burned. The combined gas turbine plant with SGSG is shown in fig. 70.
The SPGG cylinder 1 has two working pistons 2 on the same rods with the pistons of the compressors 3. When the mixture of air and fuel supplied through the nozzle 11 is burned, the gases in the cylinder expand, pushing the pistons apart. A vacuum is created in the cavities 6 of the compressor cylinders 5 and atmospheric air is sucked in through the valves 7. At the same time, air is compressed in the cavity of 4 compressor cylinders and the working pistons return to their original position.
When the pistons in the cylinder diverge, first the exhaust windows 9 open, and then the windows 10 are blown through. The exhaust gases enter the receiver 8 through the exhaust windows and from there into the gas turbine 12.
During the reverse stroke of the compressor pistons, the exhaust and purge windows are closed, air from cavity 6 is injected into the purge receiver, and the air in the working cylinder is compressed. At the end of compression, the air temperature rises and the fuel injected at that moment by the nozzle ignites. A new cycle of operation of the free-piston gas generator begins.
The effective efficiency of such a combined gas turbine plant with SGSG approaches 40%, which makes it advantageous to install them on ships. Gas turbine plants with SGSG are promising and will be widely used on ships as main engines.
Rice. 70. Scheme of a gas turbine plant with a free-piston gas generator (SPGG).
Marine nuclear installations are used to generate thermal energy as a result of the fission of the nuclei of fissile elements, which occurs in apparatuses called nuclear reactors. Vessels with such installations have an almost unlimited cruising range.
The energy released by the nuclear fission reaction when using 1 kg of uranium is approximately equal to the energy obtained by burning 1400 tons of fuel oil. The daily consumption of nuclear fuel on transport ships is estimated at only tens of grams. The replacement period for fuel elements in shipboard reactors is two to three years. Despite big weight nuclear installation, caused by the large weight of biological protection, the payload capacity of ships with nuclear installations, much more than the carrying capacity of ships of equal dimensions with generally accepted power plants. The increase in carrying capacity on these ships is due to the lack of conventional fuel on them.
To increase the speed of ships, the use of installations operating on nuclear energy, is cost-effective, allows you to increase the power of power plants without a sharp increase in their weight. The decisive advantage of shipboard nuclear installations is the absence of the need for air during their operation. This feature solves the problem of long-term movement of ships under water. As you know, ships, swimming under water in a homogeneous environment, encounter less resistance than surface ships, and, therefore, with equal engine power, they can reach high speeds. Underwater transports of large displacement can be much more profitable in operation than surface vessels of the same displacement.
As a nuclear fuel for modern ship reactors, artificially enriched uranium containing the U 235 isotope in an amount of 3-5% is used.
The part of the reactor where the chain reaction takes place is called the core. A special substance is introduced into this zone - a neutron moderator, which slows down the movement of neutrons to the speed of thermal movement. Simple water (H 2 0), heavy water (D 2 0), beryllium or graphite is used as a moderator.
According to the type of core, reactors are divided into homogeneous and heterogeneous. In homogeneous reactors nuclear fuel and moderator are a homogeneous mixture. In heterogeneous reactors, nuclear fuel is located in the moderator in the form of rods or plates called fuel elements. In ship nuclear power plants, only one type is used - heterogeneous reactors.
When a nuclear reaction takes place, about 80% of the energy is converted into heat, and 20% is released in the form of radiation (a, b and y), a- and b-radiation do not pose a particular danger. But y-radiation and neutron radiation, which have a high penetrating power, cause secondary radiation in many materials. With this radiation, serious diseases occur in the human body. To prevent such radiation, nuclear power plants must have reliable protection, called biological. Biological protection is usually made of metal, water and concrete, it has significant dimensions and weight.
The most powerful and technically advanced marine nuclear power plant on civilian ships is the power plant on the Lenin icebreaker, the most powerful icebreaker in the world.
The power of its four turbines is 44,000 liters. With.
The main power plant of the icebreaker "Lenin" is made according to the following scheme (Fig. 71). The icebreaker has three reactors 1 with pressure stabilizers 2 in the primary circuit. The moderator and coolant is ordinary water under a pressure of about 200 atm. Reactor water is supplied to the steam generators 3 at a temperature of about 325 ° C by circulating electric pumps 4. In the steam generators, steam is obtained from the second circuit at a pressure of 29 atm and a temperature of 310 ° C, which drives four steam turbine generators 5. The exhaust steam passes through the condensers 6 in the form condensate and is used again, doing work in a closed cycle.
Reactors, steam generators and core pumps are surrounded by biological protection from a layer of water and steel plates 300-420 mm thick.
Marine turbojet engines are used in hydrofoils or special purpose ships. A common diagram of a turbojet engine is shown in Fig. 72.
Rice. 71. Scheme of the power plant of the icebreaker "Lenin"
When the engine moves to the left (along arrow A), air enters its housing and is compressed by turbocharger 1. Compressed air is supplied to combustion chamber 2, in which the fuel simultaneously supplied is burned. From chamber 2, the combustion products are sent to the gas turbine 3. In the turbine, the gases partially expand, thereby doing work to drive the turbocharger. Further expansion of the gas occurs in nozzle 4, from where it escapes into the atmosphere at high speed. The reaction of the outflowing jet ensures the movement of the vessel.
A steam-gas turbine plant operating on the Walther cycle was used on German submarines in World War II in order to increase their speed while submerged. A boat with such an installation could develop high underwater speeds for 5-6 hours, reaching up to 22-25 knots.
The oxidizing agent in this cycle was high (80%) hydrogen peroxide, which, in the presence of a catalyst, decomposes in a special chamber into water vapor and oxygen, releasing a significant amount of heat. In the combustion chamber, liquid fuel was burned in oxygen with simultaneous injection of fresh water into the same place. The energy of the resulting vapor-gas mixture with high pressure and high temperature used in a steam turbine. The spent gas-vapor mixture was cooled in the condenser, where the water vapor turned into water and entered again into the feed water system, and carbon dioxide was pumped overboard.
The main disadvantages of these installations were the short sailing range of boats with maximum speeds, increased fire hazard due to the presence of a large amount of hydrogen peroxide on the boat, the dependence of their normal operation on the immersion depth, and the high cost of both the installation itself and its operation.
In England in post-war years the submarine "Exilorer" was built with a power plant of this type. During the tests, it was determined that the cost of one running hour is equivalent to the cost of 12.5 kg of gold.
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In autonomous generation - small power generation in Lately considerable attention is given gas turbines different power. Power plants at the base gas turbines are used as the main or backup source of electricity and heat for industrial or domestic facilities. gas turbines as part of power plants are designed for operation in any climatic conditions of Russia. Areas of use gas turbines practically unlimited: oil and gas industry, industrial enterprises, structures housing and communal services.
Positive use factor gas turbines in the housing sector is that the content of harmful emissions in the exhaust gases of NO x and CO is at the level of 25 and 150 ppm, respectively (for piston plants, these values are much higher), which allows you to install a power plant near residential areas. Usage gas turbines as power units of power plants avoids the construction of high chimneys.
Depending on the needs gas turbines equipped with steam or hot water waste heat boilers, which allows you to receive from the power plant either steam (low, medium, high pressure) for process needs, or hot water (DHW) with standard temperature values. You can get steam and hot water at the same time. The power of thermal energy produced by a power plant based on gas turbines, as a rule, is twice that of electricity.
At the power plant gas turbines in this configuration, the fuel efficiency increases to 90%. High usage efficiency gas turbines as power units is provided during long-term operation with maximum electrical load. With enough power gas turbines there is the possibility of combined use of steam turbines. This measure allows to significantly increase the efficiency of using the power plant, increasing the electrical efficiency up to 53%.
How much does a gas turbine power plant cost? What is its full price? What is included in the turnkey price?
Autonomous thermal power plant based on gas turbines has a lot of additional expensive, but often, just necessary equipment(a real-life example is a completed project). With the use of first-class equipment, the cost of a power plant of this level, on a turnkey basis, does not exceed 45,000 - 55,000 rubles per 1 kW of installed electric capacity. The final price of a power plant based on gas turbines depends on the specific tasks and needs of the consumer. The price includes design, construction and commissioning works. Gas turbines themselves, as power units, without additional equipment, depending on the manufacturer and power, cost from 400 to 800 dollars per 1 kW.
To obtain information on the cost of building a power plant or thermal power plant in your particular case, you must send a completed questionnaire to our company. After that, after 2-3 days, the customer-client receives a preliminary technical and commercial proposal - TCH (short example). Based on the TCH, the customer makes the final decision on the construction of a power plant based on gas turbines. As a rule, before making a decision, the client visits an existing object in order to see firsthand modern power plant and "touch everything with your hands." Directly at the facility, the customer receives answers to existing questions.
The concept of block-modular construction is often taken as the basis for the construction of power plants based on gas turbines. Block-modular design provides high level factory readiness of gas turbine power plants and reduces the construction time for energy facilities.
Gas turbines - some arithmetic on the cost of energy produced
To produce 1 kW of electricity, gas turbines consume only 0.29–0.37 m³/h of gas fuel. When burning one cubic meter of gas, gas turbines generate 3 kW of electricity and 4–6 kW of thermal energy. With the price (averaged) for natural gas in 2011, 3 rubles. per 1 m³, the cost of 1 kW of electricity received from a gas turbine is approximately 1 ruble. In addition to this, the consumer receives 1.5–2 kW of free thermal energy!
With autonomous power supply from a power plant based on gas turbines, the cost of electricity and heat produced is 3–4 times lower than the tariffs in force in the country, and this does not take into account the high cost of connecting to state power grids (60,000 rubles per 1 kW in the Moscow region, 2011).
Construction of autonomous power plants based on gas turbines allows for significant savings Money By eliminating the costs of construction and operation of expensive power lines (TL), power plants based on gas turbines can significantly increase the reliability of electrical and heat supply for both individual enterprises or organizations, and regions as a whole.
The degree of automation of a power plant based on gas turbines makes it possible to abandon a large number of service personnel. During the operation of a gas power plant, only three people ensure its operation: an operator, an electrician on duty, and a mechanic on duty. In case of emergencies, reliable protection systems are provided to ensure the safety of personnel, the safety of systems and units of the gas turbine.
Atmospheric air through an air intake equipped with a filter system (not shown in the diagram) is supplied to the input of a multistage axial compressor. The compressor compresses atmospheric air and delivers it at high pressure to the combustion chamber. At the same time, a certain amount of gas fuel is supplied to the combustion chamber of the turbine through the nozzles. Fuel and air mix and ignite. The air-fuel mixture burns, releasing a large number of energy. The energy of the gaseous products of combustion is converted into mechanical work due to the rotation of the turbine blades by jets of hot gas. Part of the energy received is used to compress the air in the turbine compressor. The rest of the work is transferred to the electric generator through the drive axle. This work is the useful work of the gas turbine. The combustion products, which have a temperature of about 500-550 °C, are removed through the exhaust tract and the turbine diffuser, and can be further used, for example, in a heat exchanger, to obtain thermal energy.
Gas turbines, as engines, have the highest specific power among internal combustion engines, up to 6 kW/kg.
As a gas turbine fuel, kerosene, diesel fuel, gas can be used.
One of the advantages of modern gas turbines is the long life cycle- engine life (full up to 200,000 hours, before overhaul 25,000–60,000 hours).
Modern gas turbines are highly reliable. There is evidence of continuous operation of some units for several years.
Many gas turbine suppliers perform field overhauls, replacing individual components without transporting them to the factory, which significantly reduces time costs.
The possibility of long-term operation in any power range from 0 to 100%, the absence of water cooling, operation on two types of fuel - all this makes gas turbines popular power units for modern autonomous power plants.
The use of gas turbines is most effective at medium power plants, and at capacities above 30 MW, the choice is obvious.
Gritsyna V.P.
In connection with the multiple growth of electricity tariffs in Russia, many enterprises are considering the construction of their own low-capacity power plants. In a number of regions, programs are being developed for the construction of small or mini thermal power plants, in particular, as a replacement for obsolete boiler houses. At a new small CHP plant with a fuel utilization rate of up to 90% with a full use of the body in production and for heating, the cost of electricity received can be significantly lower than the cost of electricity received from the power grid.
When considering projects for the construction of small thermal power plants, power engineers and specialists of enterprises are guided by the indicators achieved in the large power industry. Continuous improvement of gas turbines (GTU) for use in large-scale power generation has made it possible to increase their efficiency up to 36% or more, and the use of a combined steam-gas cycle (CCGT) has increased the electrical efficiency of thermal power plants up to 54% -57%.
However, in the small-scale power industry it is inappropriate to consider the possibility of using complex schemes of combined cycles of CCGT for the production of electricity. In addition, gas turbines, in comparison with gas engines, as drives for electric generators, lose significantly in terms of efficiency and performance characteristics, especially at low powers (less than 10 MW). Since in our country neither gas turbines nor gas piston engines have yet been widely used in small-scale stationary power generation, the choice of a specific technical solution is a significant problem.
This problem is also relevant for large-scale energy, i.e. for power systems. In modern economic conditions, in the absence of funds for the construction of large power plants on obsolete projects, which can already be attributed to domestic project CCGT 325 MW, designed 5 years ago. Energy systems and RAO UES of Russia should pay special attention to the development of small-scale power generation, at whose facilities new technologies can be tested, which will make it possible to begin the revival of domestic turbine-building and machine-building plants and, in the future, switch to large capacities.
In the last decade, large diesel or gas engine thermal power plants with a capacity of 100-200 MW have been built abroad. The electrical efficiency of diesel or gas engine power plants (DTPP) reaches 47%, which exceeds the performance of gas turbines (36%-37%), but is inferior to the performance of CCGTs (51%-57%). CCGT power plants include a large range of equipment: a gas turbine, a waste heat steam boiler, a steam turbine, a condenser, a water treatment system (plus a booster compressor if low or medium pressure natural gas is burned. Diesel generators can run on heavy fuel, which is 2 times cheaper than gas turbine fuel and can operate on low-pressure gas without the use of booster compressors.According to S.E.M.T. PIELSTICK, the total cost of operating a diesel power unit with a capacity of 20 MW over 15 years is 2 times less than for a gas turbine thermal power plant of the same capacity when using liquid fuel by both power plants.
Promising Russian manufacturer diesel power units up to 22 MW is the Bryansk Machine-Building Plant, which offers customers power units with increased efficiency up to 50% for operation both on heavy fuel with a viscosity of up to 700 cSt at 50 C and a sulfur content of up to 5%, and for operation on gaseous fuel.
The option of a large diesel thermal power plant may be preferable to a gas turbine power plant.
In small-scale power generation, with unit capacities of less than 10 MW, the advantages of modern diesel generators are even more pronounced.
Let us consider three variants of thermal power plants with gas turbine plants and gas piston engines.
The fuel utilization factor for the first two options of power plants (with different electrical efficiency) due to heat supply can reach 80% -94%, both in the case of gas turbines and for motor drives.
The profitability of all variants of power plants depends on the reliability and efficiency, first of all, of the "first stage" - the drive of the electric generator.
Enthusiasts for the use of small gas turbines are campaigning for their widespread use, noting the higher power density. For example, in [1] it is reported that Elliot Energy Systems (in 1998-1999) is building a distribution network of 240 distributors in North America providing engineering and service support for the sale of "micro" gas turbines. The power grid ordered a 45 kW turbine to be ready for delivery in August 1998. It also stated that the electrical efficiency of the turbine was as high as 17%, and noted that gas turbines were more reliable than diesel generators.
This statement is exactly the opposite!
If you look at Table. 1. then we will see that in such a wide range from hundreds of kW to tens of MW, the efficiency of the motor drive is 13% -17% higher. The indicated resource of the motor drive of the company "Vyartsilya" means a guaranteed resource until a complete overhaul. The resource of new gas turbines is a calculated resource, confirmed by tests, but not by statistics of work in real operation. According to numerous sources, the resource of gas turbines is 30-60 thousand hours with a decrease with a decrease in power. The resource of diesel engines of foreign production is 40-100 thousand hours or more.
Table 1
Main technical parameters of electric generator drives
G-gas-turbine power plant, D-gas-piston generating plant of Vyartsilya.
D - diesel from the Gazprom catalog
* The minimum value of the required pressure of the fuel gas = 48 ATA!!
Performance characteristics
Electrical efficiency (and power) According to Värtsilä data, when the load is reduced from 100% to 50%, the efficiency of an electric generator driven by a gas engine changes little.
The efficiency of a gas engine practically does not change up to 25 °C.
The power of the gas turbine drops evenly from -30°C to +30°C.
At temperatures above 40 °C, the reduction in gas turbine power (from nominal) is 20%.
Start time gas engine from 0 to 100% load is less than a minute and emergency in 20 seconds. It takes about 9 minutes to start a gas turbine.
Gas supply pressure for a gas turbine it should be 16-20 bar.
The gas pressure in the network for a gas engine can be 4 bar (abs) and even 1.15 bar for a 175 SG engine.
Capital expenditures at a thermal power plant with a capacity of about 1 MW, according to Vartsila specialists, they amount to $1,400/kW for a gas turbine plant and $900/kW for a gas piston power plant.
Combined cycle application at small CHPPs, by installing an additional steam turbine is impractical, since it doubles the number of thermal and mechanical equipment, the area of the turbine hall and the number of maintenance personnel with an increase in power only 1.5 times.
With a decrease in the capacity of the CCGT from 325 MW to 22 MW, according to the data of the NPP "Mashproekt" plant (Ukraine, Nikolaev), the front efficiency of the power plant decreases from 51.5% to 43.6%.
The efficiency of a diesel power unit (using gas fuel) with a capacity of 20-10 MW is 43.3%. It should be noted that in the summer, at a CHPP with a diesel unit, hot water supply can be provided from the engine cooling system.
Calculations on the competitiveness of power plants based on gas engines showed that the cost of electricity at small (1-1.5 MW) power plants is approximately 4.5 cents / kWh), and at large 32-40 MW gas-powered plants 3, 8 US cents/kWh
According to a similar calculation method, electricity from a condensing nuclear power plant costs approximately 5.5 US cents/kWh. , and coal IES about 5.9 cents. US/kWh Compared to a coal-fired CPP, a plant with gas engines generates electricity 30% cheaper.
The cost of electricity produced by microturbines, according to other sources, is estimated at between $0.06 and $0.10/kWh
The expected price for a complete 75 kW gas turbine generator (US) is $40,000, which corresponds to the unit cost for larger (more than 1000 kW) power plants. The big advantage of power units with gas turbines is their smaller dimensions, 3 or more times less weight.
It should be noted that the unit cost of Russian-made electric generator sets based on automobile engines with a capacity of 50-150 kW may be several times less than the mentioned turbo blocks (USA), given the serial production of engines and the lower cost of materials.
Here is the opinion of Danish experts who evaluate their experience in the implementation of small power plants.
"Investment in a completed, turnkey CHP plant operating on natural gas, with a capacity of 0.5-40 MW are 6.5-4.5 million Danish crowns per 1 MW (1 crown was approximately equal to 1 ruble in the summer of 1998). Combined cycle CHP plants below 50 MW will achieve an electrical efficiency of 40-44%.
Operating costs for lubricating oils, Maintenance and the maintenance of personnel at CHPs reach 0.02 kroons per 1 kWh produced by gas turbines. At CHP plants with gas engines, operating costs are about 0.06 dat. kroons per 1 kWh. At current electricity prices in Denmark, the high performance of gas engines more than offsets their higher operating costs.
Danish specialists believe that most CHP plants below 10 MW will be equipped with gas engines in the coming years."
conclusions
The above estimates, it would seem, unambiguously show the advantages of a motor drive at low power of power plants.
However, at present, the power of the proposed Russian-made motor drive on natural gas does not exceed the power of 800 kW-1500 kW (RUMO plant, N-Novgorod and Kolomna Machine Plant), and several plants can offer turbo drives of higher power.
Two factories in Russia: plant im. Klimov (St. Petersburg) and Perm Motors are ready to supply complete power units of mini-CHP with waste heat boilers.
In the case of organizing a regional service center issues of maintenance and repair of small turbines of turbines can be solved by replacing the turbine with a backup one in 2-4 hours and its further repair in the factory conditions of the technical center.
The efficiency of gas turbines can currently be increased by 20-30% by applying power injection of steam into a gas turbine (STIG cycle or steam-gas cycle in one turbine). In previous years, this technical solution was tested in full-scale field tests of the Vodolei power plant in Nikolaev (Ukraine) by NPP Mashproekt and PA Zarya, which made it possible to increase the power of the turbine unit from 16 to 25 MW and the efficiency was increased from 32 .8% to 41.8%.
Nothing prevents us from transferring this experience to smaller capacities and thus implementing a CCGT in serial delivery. In this case, the electrical efficiency is comparable to that of diesels, and the specific power increases so much that capital costs can be 50% lower than in a gas engine driven CHP plant, which is very attractive.
This review was carried out in order to show: that when considering options for the construction of power plants in Russia, and even more so the directions for creating a program for the construction of power plants, it is necessary to consider not individual options that may offer design organizations, but a wide range of issues, taking into account the capabilities and interests of domestic and regional equipment manufacturers.
Literature
1. Power Value, Vol.2, No.4, July/August 1998, USA, Ventura, CA.
The Small Turbine Marketplace
Stan Price, Northwest Energy Efficiency Council, Seattle, Washington and Portland, Oregon
2. New directions of energy production in Finland
ASKO VUORINEN, Assoc. tech. Sciences, Vartsila NSD Corporation JSC, "ENERGETIK" -11.1997. page 22
3. District heating. Research and development of technology in Denmark. Ministry of Energy. Energy Administration, 1993
4. DIESEL POWER PLANTS. S.E.M.T. PIELSTICK. POWERTEK 2000 Exhibition Prospectus, March 14-17, 2000
5. Power plants and electrical units recommended for use at the facilities of OAO GAZPROM. CATALOG. Moscow 1999
6. Diesel power station. Prospect of OAO "Bryansk Machine-Building Plant". 1999 Exhibition brochure POWERTEK 2000/
7. NK-900E Block-modular thermal power plant. OJSC Samara Scientific and Technical Complex named after V.I. N.D. Kuznetsova. Exhibition brochure POWERTEK 2000
