Superheated steam boiler of pure combustion high-sodium coal two-stage medium-temperature separation circulating fluidized bed

Abstract

The invention discloses a superheated steam boiler of a pure combustion high-sodium coal two-stage medium-temperature separation circulating fluidized bed. The superheated steam boiler of the pure combustion high-sodium coal two-stage medium-temperature separation circulating fluidized bed comprises a hearth; the lower side of the hearth communicates with an isobaric air chamber through a small air cap air distribution plate; a feed pipe, a buried pipe and a return port are arranged at the lower part of the hearth; an outlet of the hearth is turned to downwards move to connect with a first water cooling cavity; the lower part of the first water cooling cavity is gradually shrunk to downwards move to turn for enlargement to connect with a first-grade acceleration settlement separator; the low part of the first-grade acceleration settlement separator is connected with a settlement tank; the bottom of the settlement tank is connected with the return port; the upper part of the first-gradeacceleration settlement tank is connected with a second water cooling cavity; a snakelike pipe low-temperature superheater is arranged at the upper part of the second water cooling cavity; and an outlet of the second water cooling is serially connected with a two-grade volute cyclone separator. First and second water cooling diaphragm wall cavities are formed in the outlet of the hearth for performing the pollution reducing design and prevention of the sodium and potassium high-temperature corrosion on heated surfaces easiest to be polluted, so that the bad coking deposition phenomenon is solved, and the better effect is achieved.

Description

technical field [0001] The invention relates to a circulating fluidized bed boiler, in particular to a two-stage medium-temperature separation circulating fluidized bed superheated steam boiler purely burning high-sodium coal, which belongs to the technical field of boiler combustion equipment. Background technique [0002] At present, circulating fluidized bed boilers generally have poor adaptability to high-sodium coal in the Zhundong region of Xinjiang. The boilers that have been in operation generally burn part of the high-sodium coal, and generally have serious coking and ash accumulation. The steam temperature of the superheater drops and the sodium and potassium high-temperature corrosion , resulting in boiler failure and high exhaust gas temperature. The characteristics of Zhundong high-sodium coal are: low ash, low sulfur, low melting point of medium ash, high water content, high volatile content, medium and high calorific value, high sodium, potassium, calcium, str...

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Problems solved by technology

[0002] At present, circulating fluidized bed boilers generally have poor adaptability to high-sodium coal in the Zhundong region of Xinjiang. The boilers that have been in operation generally burn part of the high-sodium coal, and generally have serious coking and ash accumulation. The steam temperature of the superheater drops and the sodium and potassium high-temperature corrosion , resulting in boiler failure and high exhaust gas temperature

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