Method and device for reducing feedwater dissolved oxygen of CCPP waste heat boiler

Abstract

The invention discloses a method and device for reducing feedwater dissolved oxygen of a CCPP waste heat boiler. A heat exchanger and a first deaerator are introduced on the basis of an existing pressure deaerator, boiler return water at the first temperature is heated to the second temperature through the heat exchanger, the boiler return water at the second temperature is pre-deoxidized throughthe first deaerator, the first deaerator heats and pre-deoxidizes the boiler return water through low-pressure steam, and thus dissolved oxygen of the boiler return water is reduced to meet the process requirement of inlet dissolved oxygen of the original pressure deaerator; deoxidized water heated and pre-deoxidized by the first deaerator serves as a heating medium of the heat exchanger, the deoxidized water is subjected to heat exchanging with the boiler return water at the first temperature through the heat exchanger, the boiler return water at the first temperature is heated, and thus theconsumption of the low-temperature steam of the first deaerator is greatly decreased; meanwhile the inlet temperature of the pressure deaerator is lowered, no influence on the heat balance of a wasteheat boiler system and the efficiency of a turbine system is caused, and the balance of the whole-system heat load is prevented from being broken.

Description

technical field [0001] This application belongs to the technical field of waste heat power generation in iron and steel enterprises, and specifically relates to a method and device for reducing dissolved oxygen in CCPP waste heat boiler feed water, which is suitable for CCPP waste heat boilers in iron and steel joint enterprises. Background technique [0002] The gas-steam combined cycle power generation (CCPP) waste heat boiler utilizes the high-temperature flue gas discharged from the combustion engine to generate steam, which enters the turbine generator for power generation. It is one of the means for iron and steel enterprises to efficiently utilize waste heat and energy. In order to realize cascade utilization of energy, the intermediate stage of the steam turbine is usually equipped with extraction steam, which is supplied to users such as heat exchange stations in the factory area; the exhaust steam of the steam turbine is supplied to the seawater desalination process...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the above-mentioned technical problems, the present invention provides a method and device for reducing dissolved oxygen in CCPP waste heat boiler feed water, which solves the problem of excessive dissolved oxygen in feed water caused by the lax steam condensation and return water system and the large amount of new water replenishment, and avoids the boiler Oxygen corrosion in the steam-water system reduces the risk of boiler tube burst accidents and effectively ensures the reliable operation of the boiler system

Images