Device for preventing low-load NOX of circulating fluidized bed boiler from exceeding standard and operation method thereof

Abstract

The invention discloses a device for preventing low-load NOx of a circulating fluidized bed boiler from exceeding the standard and an operation method thereof. The device comprises a heat shielding plate, wherein the heat shielding plate is arranged in a hearth of the boiler, the heat shielding plate is used for shielding a water cooling wall in the hearth, a limiting opening is formed in the topof the hearth, a connecting piece penetrates through the limiting opening to be connected with the heat shielding plate, and the connecting piece is used for driving the heat shielding plate to move and rotate. The device has the advantages that the heat shielding plate is arranged on the surface of the water cooling wall, when the boiler runs at a low load, the water cooling wall is shielded through the heat shielding plate, and heat absorbed by the water cooling wall in the hearth is reduced, so that the flue gas temperature is indirectly increased, the outlet temperature of the low-load hearth adapts to a temperature window of SNCR, the denitration efficiency under the low load is improved, it is ensured that the NOx emission under low load meets the ultralow emission requirement, and the economical efficiency of the boiler operation is ensured.

Description

technical field [0001] The invention belongs to the field of circulating fluidized bed boilers, in particular to a method for avoiding low load NO of circulating fluidized bed boilers. X Excessive devices and operating methods. Background technique [0002] Circulating fluidized bed (CFB) boilers have the following advantages: high combustion efficiency, wide fuel adaptability, low pollutant emission intensity, good load regulation performance and efficient comprehensive utilization of resources, etc., and are widely used in power generation at home and abroad industry. [0003] For NOx emissions, there are two main control methods for CFB boilers. One is low-NOx combustion technology, which reduces the formation of NOx during the combustion process; the other is flue gas denitrification technology, which removes the generated NOx from flue gas. Flue gas denitration technology mainly includes selective non-catalytic reduction (SNCR) or selective catalytic reduction (SCR). ...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problems existing in the prior art, the present invention provides a device for avoiding excessive NOx at low load of the circulati...

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