Joint air-cooling system and control method

Abstract

The invention provides a joint air-cooling system and a control method. The joint air-cooling system comprises a steam turbine, an indirect cooling condenser and a condensation water precision processing unit. A generator is connected to the steam turbine. A direct air-cooling unit is a direct air-cooling radiator. An inlet of the direct air-cooling radiator is connected with the steam turbine, and an outlet of the direct air-cooling radiator is connected with the condensation water precision processing unit. A multi-level heater is connected to the condensation water precision processing unit. An inlet of the indirect cooling condenser is connected with the steam turbine, and an outlet of the indirect cooling condenser is connected with the multi-level heater. The indirect cooling condenser is further connected with an indirect air-cooling unit. According to the joint air-cooling system and the control method, exhausted steam of the steam turbine is distributed, a part of the exhausted steam of the steam turbine enters a direct air-cooling condenser to be subjected to heat exchanging, and the other part of the exhausted steam of the steam turbine enters the indirect cooling condenser to be subjected to heat exchanging; the back pressure of the exhausted steam of the steam turbine can be further reduced through a composite circulation cooling system, the vacuum of a machine set is improved, and then the economy of the machine set is improved.

Description

technical field [0001] The invention relates to the construction of an air-cooling unit in a thermal power plant, the technical transformation of the "upper-large and smaller-unit" units, and the technical transformation of coal-fired generating units in harsh environment areas, and specifically relates to a combined air-cooling system and a control method. Background technique [0002] In recent years, air-cooled units have developed rapidly in foreign countries and in Northeast my country, North China, and Northwest China. In comparison, air-cooled units have a water-saving rate of 80% compared with traditional wet-cooled units, showing great advantages in coal-rich and water-scarce areas . However, in the case of high ambient temperature in summer, the direct air-cooled unit cannot be fully loaded due to high back pressure, and the output of the unit is insufficient when the power demand is large, resulting in poor operating economy of the unit, and Due to its high back p...

AI Technical Summary

Problems solved by technology

However, in the case of high ambient temperature in summer, the direct air-cooled unit cannot be fully loaded due to high back pressure, and the output of the unit is insufficient when the power demand is large, resulting in poor operating economy of the unit, and Due to its high back pressure, a lot of online power is wasted

In addition, during low load in winter or when the unit is started and shut down, it is easy to freeze due to the small amount of direct air-cooled steam intake, which is also extremely unfavorable to the vacuum and load capacity of the unit, and it is also prone to freeze crack damage to the air-cooled heat exchanger

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