Exhaust duct and boiler

Patent metadata

Field	Value
Publication number	US-10323844-B2
Application number	US-201515533184-A
Country	US
Kind code	B2
Filing date	Sep 15, 2015
Priority date	Dec 12, 2014
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

In an exhaust duct and a boiler, there are provided: a flue gas duct through which flue gases pass; a first hopper provided to the flue gas duct, the first hopper collecting PA in the flue gases; a low-repulsion section provided to the upstream side or the downstream side of the first hopper in the direction of flow of the flue gases, the low-repulsion section having a lower coefficient of repulsion than the inner wall surface of the flue gas duct; and a popcorn-ash-trapping section for trapping PA in the flue gases, the popcorn-ash-trapping section provided to the downstream side of the first hopper and the low-repulsion section in the direction of flow of the flue gases, whereby it is possible for solid particles in the flue gases to be properly trapped.

First claim

The invention claimed is:

1. An exhaust duct, comprising:
a flue gas duct through which a flue gas flows, the flue gas duct having a vertical section through which the flue gas flows downward in a vertical direction and a horizontal section connected to the vertical section;
a hopper which in the flue gas duct and configured to collect solid particles in the flue gas, the hopper being located below a connection section between the vertical section and the horizontal section of the flue gas duct;
a low-repulsion section on an upstream side of the hopper in a direction of flow of the flue gas, and on a lower wall surface section of the vertical section, and the low-repulsion section having a lower coefficient of repulsion than that of an inner wall surface of the flue gas duct; and
a solid particle trapping section on the inner wall surface of the flue gas duct on a downstream side of both the hopper and the low-repulsion section in the direction of flow of the flue gas, and the solid particle trapping section being configured to trap solid particles in the flue gas;
wherein the lower wall surface section of the vertical section includes an inclination surface and a horizontal surface arranged in the direction of the flue gas flow, and the low-repulsion section extends from the inclination surface to the horizontal surface so as to cover at least a portion of the inclination surface and the horizontal surface.

2. The exhaust duct according to claim 1 , wherein the low-repulsion section includes an inclination surface inclined in the same direction as an inclination surface of the hopper.

3. The exhaust duct according to claim 2 , wherein the inclination surface of the low-repulsion section extends to the inclination surface of the hopper.

4. The exhaust duct according to claim 1 , wherein the solid particle trapping section is oriented to extend in the vertical direction.

5. The exhaust duct according to claim 1 , wherein the solid particle trapping section is inclined such that an upper portion of the solid particle trapping section is positioned on the upstream side of the hopper in the direction of flow of the flue gas.

6. The exhaust duct according to claim 1 , wherein the solid particle trapping section is provided in a region of 30% to 50% of the entire height of the flue gas duct from the lower wall surface section in the horizontal section.

7. The exhaust duct according to claim 1 , wherein the solid particle trapping section is provided in a region of 100% of an entire height of the flue gas duct.

8. The exhaust duct according to claim 1 , wherein the vertical section is a first vertical section, the hopper is a first hopper, the connection section is a first connection section, and the low-repulsion section is a first low-repulsion section, the flue gas duct further having a second vertical section connected to the horizontal section and through which the flue gas flows upward in a vertical direction, the exhaust duct further comprising:
a second hopper below a second connection section between the horizontal section and the second vertical section, and
a second low-repulsion section on a standing wall surface section in the second vertical section facing the horizontal section on the downstream side of the second hopper in the direction of flow of the flue gas.

9. The exhaust duct according to claim 8 , wherein the solid particle trapping section is a first solid particle trapping section, further comprising a second solid particle trapping section on the inner wall surface of the flue gas duct on a downstream side of both the second hopper and the second low-repulsion section in the direction of flow of the flue gas, the second solid particle trapping section being configured to trap solid particles in the flue gas, the second solid particle trapping section oriented to extend in the horizontal direction.

10. The exhaust duct according to claim 9 , wherein the second solid particle trapping section is provided in a region of 30% to 50% of a horizontal length of the second vertical section from the standing wall surface section in the second vertical section facing the horizontal section.

11. A boiler comprising:
a furnace having a hollow shape and oriented to extend in a vertical direction;
combustion equipment configured to blow a fuel toward an inner portion of the furnace and to combust the fuel;
the exhaust duct according to claim 1 connected to a downstream side in a direction of flow of a flue gas in the furnace; and
a heat collection section in the exhaust duct and configured to collect heat in the flue gas.

Assignees

• Mitsubishi Hitachi Power Sys

Inventors

• Oda Manabu
• Kushioka Kiyonori
• Todaka Shimpei
• Kiyosawa Masashi
• Miyanishi Hideo
• Kako Hiroshi

Classifications

• F23J15/022

  for removing solid particulate material from the gasflow · CPC title

• B01D45/08

  by impingement against baffle separators · CPC title

• F23J2217/20

  by baffles · CPC title

• F23J3/04 Primary

  Traps · CPC title

• F23M5/00

  Casings; Linings; Walls · CPC title