CN-122015111-A - Steam heating device for boiler ignition of thermal power plant

CN122015111ACN 122015111 ACN122015111 ACN 122015111ACN-122015111-A

Abstract

The invention discloses a steam heating device for boiler ignition of a thermal power plant, which relates to the field of boiler preheating and comprises a preheating box communicated with a filtering flue, wherein the preheating box comprises a box body with an upper opening and a lower opening, and two connecting covers respectively connected with the upper opening and the lower opening of the box body, a plurality of supporting frames, a plurality of groups of heat exchange assemblies and a plurality of groups of heat exchange assemblies, wherein the supporting frames are equidistantly arranged in the box body, two ends of the supporting frames are fixedly connected with side walls of two ends of the inner part of the box body respectively through welding, and the heat exchange assemblies are equidistantly arranged along the length direction of the supporting frames. According to the invention, by arranging the high-temperature steam air inlet pipeline communicated with the adjacent high-temperature steam pipeline and the preheating box structure for recovering the waste heat of the flue gas, the dual-mode operation of switching the steam heating and the normal operation stages into the flue gas heating can be realized in the ignition starting stage of the boiler, so that the idling of equipment is avoided, and the utilization rate of the equipment is improved.

Inventors

XU CHENCHEN
ZHAI LONGFEI
PAN PENG
WU JU
GUO FENG
HU HONG
CHEN LIANG
HAN PENG

Assignees

国家能源泰安热电有限公司

Dates

Publication Date: 20260512
Application Date: 20260325

Claims (10)

1. A steam heating device for ignition of a boiler of a thermal power plant, comprising: The preheating box (1) is communicated with the filtering flue, and the preheating box (1) comprises a box body (101) with a hollow upper opening and a hollow lower opening, and two connecting covers (105) respectively connected with the upper opening end and the lower opening end of the box body (101); The plurality of supporting frames (2) are arranged in the box body (101) at equal intervals, and two ends of the plurality of supporting frames (2) are fixedly connected with side walls at two ends inside the box body (101) through welding respectively; Multiunit heat transfer subassembly (3), multiunit heat transfer subassembly (3) are followed equidistant on the length direction of support frame (2), heat transfer subassembly (3) are snakelike setting, heat transfer subassembly (3) are including outer tube (301), the cladding has inner tube (302) in outer tube (301), the outer wall winding of inner tube (302) has flight (303), flight (303) are located outer tube (301) inner chamber with between inner tube (302) outer wall to form spiral passageway confession warm-air conveying heat transfer, the one end outer wall of outer tube (301) is connected with air-supply line (31), just the other end outer wall connection of outer tube (301) has air-out pipe (32), air-supply line (31) with air-out pipe (32) respectively with spiral passageway both ends are linked together.
2. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 1, wherein the input ends of a plurality of the air inlet pipes (31) are communicated with a preheating air inlet pipeline (4), and the input ends of the preheating air inlet pipeline (4) are connected with an external air pump; The output ends of the air outlet pipes (32) are communicated with a preheated air outlet pipeline (5), and part of preheated air is conveyed to a coal mill in the power generation system by the output ends of the preheated air outlet pipeline (5) so as to carry pulverized coal to form an air-powder mixture and conveyed to a burner nozzle through a pipeline; The input ends of the inner pipes (302) are communicated with a high-temperature steam inlet pipeline (6), the input end of the high-temperature steam inlet pipeline (6) is communicated with a high-temperature steam pipeline in an adjacent unit boiler, and a first valve (61) is arranged between the input end of the high-temperature steam inlet pipeline (6) and the high-temperature steam pipeline in the adjacent unit boiler; The output ends of the inner pipes (302) are communicated with a high-temperature steam outlet pipeline (7), the output end of the high-temperature steam outlet pipeline (7) is communicated with a lower header at the lower end of the boiler water wall, and a second valve (71) is arranged between the high-temperature steam outlet pipeline (7) and the lower header.
3. A steam heating device for ignition of a boiler of a thermal power plant according to claim 2, characterized in that the spiral piece (303) is fixedly connected with the outer wall of the inner tube (302) by welding, and the clearance delta = 8-15mm between the spiral piece (303) and the outer tube (301), and the pitch P of the spiral piece (303) is (6-16) ×delta.
4. A steam heating device for ignition of a boiler of a thermal power plant according to claim 3, characterized in that a high temperature resistant sealing ring is arranged between the two ends of the outer tube (301) and the connecting part of the inner tube (302), the outer tube (301) is composed of two half-arranged shells, a high temperature resistant sealing gasket (304) is arranged between the two shells, and the two shells are fixedly connected with each other through bolts to form the outer tube (301).
5. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 4, wherein the ash cleaning component (8) for cleaning the outer walls of a plurality of groups of heat exchange components (3) is arranged below the supporting frame (2), the ash cleaning component (8) comprises a plurality of air pipes (801) with one closed end, the air pipes (801) are equidistantly arranged in the box body (101), two ends of the air pipes (801) are respectively and rotatably connected with the inner walls of the two ends of the box body (101) through bearings, and a plurality of air holes (802) which are equidistantly arranged are formed in two sides of the outer wall of the air pipe (801); the dust removing pipeline (803) is arranged on the outer side of the opening end of the air pipe (801), and the opening end of the air pipe (801) is rotationally connected with the dust removing pipeline (803) through a rotary joint (804).
6. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 5, wherein the input end of the ash removing pipeline (803) is communicated with the high-temperature steam outlet pipeline (7), and a third valve (81) is arranged between the ash removing pipeline (803) and the high-temperature steam outlet pipeline (7).
7. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 6, wherein a communication pipeline (9) is arranged between the preheating air inlet pipeline (4) and the high-temperature steam inlet pipeline (6), and a fourth valve (91) is arranged at the joint of the communication pipeline (9) and the high-temperature steam inlet pipeline (6).
8. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 7, wherein a driving assembly (10) is arranged among a plurality of air pipes (801), the driving assembly (10) comprises a motor (1001), the motor (1001) is rotationally connected with the box body (101) through a shaft rod and a bearing, and a driving gear (1002) is arranged at the output end of the motor (1001); One end of each of the plurality of air pipes (801) is fixedly connected with a driven gear (1003), the plurality of driven gears (1003) are meshed in a linear sequence, and one driven gear (1003) is meshed with the motor (1001).
9. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 8, wherein the high-temperature steam inlet pipeline (6) and the preheating wind inlet pipeline (4) are distributed on two sides of the preheating box (1) in a manner of being opposite to each other.
10. The steam heating device for the ignition of the boiler of the thermal power plant according to claim 9, wherein a plurality of first strip-shaped grooves (102) are formed in two opposite side walls of the box body (101), two ends of the air inlet pipe (31), the air outlet pipe (32) and the inner pipe (302) are respectively overlapped at the bottoms of the corresponding first strip-shaped grooves (102), a plurality of second strip-shaped grooves (104) which are matched with the two groups of first strip-shaped grooves (102) in an up-down symmetrical mode are formed in the lower end of the side wall (103), the tops of the plurality of second strip-shaped grooves (104) are respectively contacted with two ends of the air inlet pipe (31), the air outlet pipe (32) and the inner pipe (302), and high-temperature resistant sealing gaskets are respectively arranged on the inner walls of the first strip-shaped grooves (102) and the second strip-shaped grooves (104).

Description

Steam heating device for boiler ignition of thermal power plant Technical Field The invention relates to the field of boiler preheating, in particular to a steam heating device for boiler ignition of a thermal power plant. Background In the ignition start-up stage of a thermal power plant boiler, the temperature in a hearth is usually required to be raised to be higher than the ignition temperature of coal dust. In the prior art, the air is preheated by adopting the mode of heating air by adjacent machine steam, but the traditional steam heating device has the problems of low heat exchange efficiency, large equipment occupation, single function and the like. In addition, the existing air preheater and the steam heater are usually arranged independently, the equipment investment cost is high, and the steam heating device is easy to idle after the boiler normally operates. Part of schemes adopt flue gas waste heat recovery, but double-station requirements of a starting stage and a normal operation stage are difficult to meet. Disclosure of Invention The invention aims to solve the problems in the prior art and provides a steam heating device for ignition of a boiler of a thermal power plant. The steam heating device for the ignition of the boiler of the thermal power plant comprises a preheating box communicated with a filtering flue, wherein the preheating box comprises a box body with an upper opening and a lower opening which are hollow, and two connecting covers respectively connected with the upper opening end and the lower opening end of the box body; The plurality of support frames are arranged in the box body at equal intervals, and two ends of the plurality of support frames are fixedly connected with side walls of two ends of the inner part of the box body respectively through welding; The multiunit heat exchange assembly, multiunit heat exchange assembly follows the equidistant range on the length direction of support frame, heat exchange assembly is the snakelike setting, heat exchange assembly includes the outer tube, the cladding has the inner tube in the outer tube, the outer wall winding of inner tube has the flight, the flight is located outer tube inner chamber with between the inner tube outer wall to form the screw channel and supply the preheating wind to carry heat transfer, the one end outer wall connection of outer tube has the air-supply line, just the other end outer wall connection of outer tube has out the tuber pipe, the air-supply line with it is linked together respectively with the screw channel both ends to go out the tuber pipe. As a still further proposal of the invention, the input ends of the air inlet pipes are communicated with a preheating air inlet pipeline, and the input ends of the preheating air inlet pipeline are connected with an external air pump; The output ends of the air outlet pipes are communicated with a preheated air outlet pipe, and part of preheated air is conveyed to a coal mill in the power generation system by the output ends of the preheated air outlet pipe so as to carry pulverized coal to form an air-powder mixture and conveyed to a burner nozzle through a pipeline; The input ends of the inner pipes are communicated with high-temperature steam inlet pipelines, the input ends of the high-temperature steam inlet pipelines are communicated with high-temperature steam pipelines in adjacent unit boilers, and a first valve is arranged between the input ends of the high-temperature steam inlet pipelines and the high-temperature steam pipelines in the adjacent unit boilers; The output ends of the inner pipes are communicated with a high-temperature steam outlet pipeline, the output ends of the high-temperature steam outlet pipeline are communicated with a lower header at the lower end of the boiler water-cooled wall, and a second valve is arranged between the high-temperature steam outlet pipeline and the lower header. As a still further scheme of the invention, the spiral sheets are fixedly connected with the outer wall of the inner tube through welding, the clearance delta between the spiral sheets and the outer tube is 8-15mm, and the pitch P of the spiral sheets is (6-16) multiplied by delta so as to adapt to heat exchange requirements under different flow rates. As a still further scheme of the invention, a high-temperature-resistant sealing ring is arranged between the two ends of the outer tube and the connecting part of the inner tube, the outer tube consists of two half shells, a high-temperature-resistant sealing gasket is arranged between the two shells, and the two shells are fixedly connected through bolts to form the outer tube. The invention further provides a scheme that an ash cleaning component for cleaning the outer walls of a plurality of groups of heat exchange components is arranged below the supporting frame, the ash cleaning component comprises a plurality of air pipes with one end closed, the air pipes are equidistantly arranged in