Types of steam turbines
A steam turbine is a mechanism that converts thermal energy obtained from steam into rotational energy
Turbines operate when they contain heated steam, which is a source of energy. This steam enters the turbines from a special boiler. The temperature of the steam entering the turbine may vary. But the main indicators are within 490-580 degrees Celsius. The pressure also varies. Its main indicators are 90 atmospheres, 140 atmospheres, 230 atmospheres.
Steam turbines are classified as follows: backpressure, combined heat and power with steam extraction for production, condensing, combined heat and power.
All these turbines differ in the amount of steam used in operation and the amount of steam that was not used in production, but used for other needs.
Condensing turbines
It is the most common type of steam turbine in production. Usually, such a turbine is equipped with a condenser - a device designed to collect used steam. Absolutely all the exhaust steam enters the condenser.
The main task of condensing steam turbines is to generate electricity. Accordingly, this type of turbine is used in power plants. They can also be installed at thermal power plants, but they are usually not used there. Steam from the boiler enters the turbine and does the work necessary to generate electricity. The possibility of obtaining thermal energy from such turbines is present, but is usually not used.
In Soviet times, the Leningrad Metal Plant was engaged in the production of such pipes. Now it is JSC "Power Machines".
Cogeneration turbines
They are turbines of the "T" type. They are widely used in thermal power plants, since with their help it is possible to generate not only electricity but also thermal energy.
The turbine is capable of extracting steam using a rotary diaphragm. This process is controlled. The extracted steam then enters certain heaters, from which the heat energy is transferred to water.
In summer, cogeneration turbines are capable of operating in condensation mode. In this case, the steam does not reach the network heaters, but is used in full to generate electricity.
The Ural Turbine Plant is engaged in the production of cogeneration turbines.
Cogeneration turbines with industrial steam extraction
Turbines marked "PT"
The name of these turbines makes it clear that a certain part of the steam in the process of energy production is used for industrial needs (for example, for the operation of the plant itself, etc.). After that, the steam returns in the form of liquid, that is, condensate, or completely evaporates.
At the moment, cogeneration turbines are practically not used in production, with rare exceptions. In the USSR they were popular for installation at thermal power plants near industrial enterprises, factories, etc.
Backpressure turbines
Backpressure turbines are marked "P".
The peculiarity of backpressure turbines is the absence of a condenser, where the used steam would flow. Therefore, the latter in turn is used by an external consumer, which is somewhat similar to industrial-type cogeneration turbines.
At the moment, backpressure turbines, as well as turbines marked "PT", are not used in production, except for individual cases. In Soviet times, this model was still used, but after the collapse of the union, the need for such types of turbines disappeared, since there was a problem in finding an external consumer. Without the latter, it is impossible to use backpressure turbines to generate energy, and they have become unnecessary.
But then engineers found an excellent solution to improve backpressure turbines. In addition to them, turbines marked "K" were installed, that is, condensing, designed to work with steam with low pressure. As is known, turbines of the "P" type require the presence of an external consumer, which is solved with the help of condensing turbines. After the steam has worked in the backpressure turbines, it enters the K-type turbines, where it finally completes its work and turns into condensate.