Pre-drying brown coal power generation system integrated with air heater and pre-drying brown coal power generation method

Abstract

The invention discloses a pre-drying brown coal power generation system integrated with an air heater and a pre-drying brown coal power generation method. The system comprises a coal-fired power generation system body, a brown coal preheater, a superheated steam fluidized bed drier with an internal heater, an air heater system body and the like. An outlet of the brown coal preheater is connected with an inlet of the superheated steam fluidized bed drier with the internal heater, an outlet of the drier is connected with an inlet of a coal mill, and part of moisture in brown coal is removed in the drier. A heat source inlet of the internal heater is connected with a steam extraction opening of a certain level of a turbine, and an outlet of the internal heater is connected with the hydrophobic side of a corresponding reheating heater. The operation mode of the air heater system changes according to different loads of the air heater. The air heater system can safely and efficiently work in different seasons under different brown coal moisture contents and different dry degrees, waste heat of smoke exhausted from a boiler and waste heat of dried tail gas can be utilized at the same time, and the adverse influence of operation of the air heater on power generation efficiency is eliminated.

Description

Technical field: [0001] The invention belongs to the field of coal-fired thermal power generation, and in particular relates to a pre-dried lignite power generation system and method with an integrated air heater. Background technique: [0002] Lignite is a kind of inferior coal with high water content, high volatile content, high ash content, low calorific value and easy spontaneous combustion. Lignite reserves are huge, easy to mine and generally low in price. The total moisture of lignite is generally between 30% and 60%, and direct combustion will lead to low power generation efficiency, which restricts the application of lignite in the field of thermal power generation. my country's lignite is mainly distributed in the eastern part of Inner Mongolia, where the winter is cold and long. In order to ensure the safe operation of the air preheater, it is necessary to operate the air heater. The traditional air heater uses the steam extracted from the steam turbine as the h...

AI Technical Summary

Problems solved by technology

The traditional air heater uses steam extraction from the steam turbine as the heat source, but this will reduce the output of the steam turbine, and the operation of the air heater will increase the exhaust gas temperature of the boiler, reduce the efficiency of the boiler, and then lead to a decrease in the efficiency of the power generation system

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