Once-through boiler starting system and method

Abstract

The invention discloses a once-through boiler starting system and method. The system comprises a separator water storage tank, a pressure flash vessel, a high-pressure heater, a deaerator, a boiler side auxiliary steam header, a turbine side auxiliary steam header, a boiler reheater and a unit drainage groove. An outlet of the separator water storage tank is connected with an inlet of the pressure flash vessel. The pressure flash vessel is provided with two steam outlets, one steam outlet exhausts steam into atmosphere, and the other steam outlet exhausts steam to the high-pressure heater steam side. The pressure flash vessel is provided with two water outlets, one water outlet drains water to the deaerator, and the other water outlet drains water to the unit drainage groove. The boiler reheater supplies the steam to the boiler side auxiliary steam header, and the boiler side auxiliary steam header communicates with the turbine side auxiliary steam header. According to the method, by means of the pressure flash vessel, the water amount and the heat amount of once-through boiler starting drainage are recycled, and the temperature of boiler water supply is raised. The boiler reheater is used for supplying the steam to the boiler auxiliary steam header, dependency of unit starting on external steam is reduced, the steam exhausted to a condenser by means of a bypass is reduced, and the effects of saving energy and cost are achieved.

Description

Technical field: [0001] The invention belongs to the technical field of electric power, and in particular relates to a system and method for starting a once-through boiler. Background technique: [0002] The power station unit needs a certain amount of steam in the initial start-up and shutdown stages. The steam is mainly used for shaft seals, steam source for steam-driven feed pumps, heating for deaerators, soot blowing for air preheaters, and air heaters. These steams are currently provided by neighboring engines or start-up boilers. The steam provided by the adjacent machine or the starting boiler is collectively referred to as external steam. The external steam supply is generally sent to the auxiliary steam header of the machine, and the steam used by the machine is taken from the auxiliary steam header as needed. [0003] In addition to the external steam source, the steam source of the conventionally designed auxiliary steam header also takes the steam source from t...

AI Technical Summary

Problems solved by technology

[0027] The purpose of the present invention is to provide a once-through boiler start-up system and method to solve the problem that a large amount of external steam is used in the start-up stage of the current unit, and the steam and high-temperature and high-pressure saturated water generated by the unit itself cannot be used.

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