External ash circulating system of double-bed internal circulating fluidized bed boiler

Abstract

The utility model discloses an external ash circulating system of a double-bed internal circulating fluidized bed boiler, which relates to the technical field of internal circulating fluidized bed boilers and is arranged on left and right furnace walls of a hearth of the double-bed internal circulating fluidized bed boiler. Comprising a circulating ash channel, an inspection door, an ash cleaning hole, a first-stage ash falling pipe, a first-stage ash discharging valve, a full-automatic injection type ash return system, an observation hole, a second-stage ash falling pipe and a second-stage ash discharging valve. Circulating ash is led out from the circulating ash channel through the first-stage ash falling pipe and then enters an inlet of the full-automatic injection and suction type ash return system, unburnt particles are returned to the hearth through the injection and suction type ash return system to be circularly burnt until the particles are burnt out, and the burnt particles settle to the bottom ash falling pipe and then are discharged through the second-stage ash falling pipe and the ash discharging valve. The external ash circulating system of the double-bed internal circulating fluidized bed boiler is provided with the inspection door and the observation hole, so that the state of ash circulation can be observed and adjusted at any time.

Description

Technical Field

[0001] This utility model belongs to the technical field of circulating fluidized bed boilers, and specifically relates to an external ash circulation system for a dual-bed internal circulating fluidized bed boiler. Background Technology

[0002] Ash return in circulating fluidized bed boilers has always been a bottleneck hindering normal boiler operation. Existing internal circulating fluidized bed boilers with a dual-bed structure have an internal ash circulation system, meaning the system is located inside the boiler, in the middle of the two furnace beds, separating the left and right furnace chambers. Figure 1 As shown, the area within the dashed box represents the ash circulation system. This type of built-in ash circulation system has a high ambient temperature in the circulating ash channel, with no significant temperature difference between it and the interior of the furnace on both sides, resulting in poor ash return efficiency. Because the circulating ash channel is inside the boiler, any malfunction requires access to the furnace for repairs, which can only be done after the furnace has cooled down, leading to long shutdown times and high maintenance costs. Summary of the Invention

[0003] The purpose of this utility model is to overcome the shortcomings of the existing technology and provide an external ash circulation system for a dual-bed internal circulation fluidized bed boiler, which has a simple structure, reliable operation, strong visibility, convenient operation and maintenance, and low maintenance cost.

[0004] The technical solution adopted in this utility model is as follows:

[0005] The external ash circulation system of the double-bed internal circulating fluidized bed boiler is installed on the furnace walls on the left and right sides of the furnace of the double-bed internal circulating fluidized bed boiler, including circulating ash channels, inspection doors, ash cleaning holes, primary ash discharge pipes and ash discharge valves, observation holes, fully automatic jet suction ash return system, and secondary ash discharge pipes and ash discharge valves.

[0006] The bottom of the circulating ash channel is connected to the inlet of the primary ash discharge pipe. The outlet end of the primary ash discharge pipe is the primary ash discharge valve. The primary ash discharge valve is connected to the top of one side of the fully automatic jet suction ash return system. The bottom of one side of the fully automatic jet suction ash return system is connected to the secondary ash discharge pipe and the secondary ash discharge valve. The other side of the fully automatic jet suction ash return system is embedded in the furnace wall and connected to the furnace.

[0007] The advantages of this utility model are:

[0008] 1. The ash circulation system is located on both sides of the furnace, which facilitates inspection and maintenance, and the maintenance time is short and the maintenance cost is low; 2. It is equipped with inspection doors, ash cleaning holes and observation holes, so that the status of circulating ash can be observed and adjusted at any time; 3. This utility model has a simple structure, reliable operation, easy processing and low cost. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the background technology structure;

[0010] Figure 2 This is a schematic diagram of the installation position of this utility model on a dual-bed internal circulating fluidized bed boiler;

[0011] Figure 3 This is a schematic diagram of the overall structure of this utility model;

[0012] Figure 4 This is a cross-sectional view of a component of this utility model;

[0013] Figure 5 This is a schematic diagram of the ejector suction type ash return system of this utility model. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings.

[0015] like Figures 2 to 4 As shown, the external ash circulation system of the double-bed internal circulating fluidized bed boiler is installed on the furnace walls on the left and right sides of the furnace of the double-bed internal circulating fluidized bed boiler, including circulating ash channel 1, inspection door 2, ash cleaning hole 3, primary ash discharge pipe 4, primary ash discharge valve 5, fully automatic injection suction ash return system 6, observation hole 7, secondary ash discharge pipe 8, secondary ash discharge valve 9.

[0016] The bottom of the circulating ash channel 1 is connected to the inlet of the primary ash discharge pipe 4. The outlet end of the primary ash discharge pipe 4 is the primary ash discharge valve 5. The primary ash discharge valve 5 is connected to the top of one side of the fully automatic jet suction ash return system 6. The bottom of one side of the fully automatic jet suction ash return system 6 is connected to the secondary ash discharge pipe 8 and the secondary ash discharge valve 9. The other side of the fully automatic jet suction ash return system 6 is embedded in the furnace wall and connected to the furnace.

[0017] The bottom of the circulating ash channel 1 is designed to be wider than 400mm and is equipped with an inspection door 2 for entry.

[0018] The side of the circulating ash channel 1 is provided with a cleaning hole 3 for performing routine cleaning operations.

[0019] Furthermore, to facilitate the observation of the ash return status, the fully automatic jet suction ash return system 6 is provided with an observation hole 7 on its side.

[0020] The external ash circulation system of the dual-bed internal circulation fluidized bed boiler is symmetrically arranged on the outer walls of the furnace on both the left and right sides of the furnace.

[0021] The structure of the fully automatic ejector-type ash return system 6 in this utility model is as follows: Figure 5 The image shown represents our company's existing patents.

[0022] In implementation, this utility model only requires a simple change to the layout of the original separator, so that the circulating ash separated by the separator enters the circulating ash channel 1 on both sides of the furnace wall. After the circulating ash falls to the bottom of the circulating ash channel 1, it is led out by the first-stage ash discharge pipe 4 at the bottom of the circulating ash channel, and falls into the inlet of the fully automatic ejector suction ash return system 6 through the first-stage ash discharge valve 5. The unburned particles are returned to the furnace by the fully automatic ejector suction ash return system 6 for circulating combustion until they are burned out. The burned particles settle to the bottom of the fully automatic ejector suction ash return system 6, and are discharged through the second-stage ash discharge pipe 8 and the second-stage ash discharge valve 9.

[0023] Personnel can observe the ash return status at any time through observation hole 7, and perform routine ash cleaning operations through ash cleaning hole 3. They can also enter the circulating ash channel 1 through inspection door 2 for cleaning, inspection, and maintenance. Under normal operating conditions, the primary ash discharge valve 5 is normally open, and the secondary ash discharge valve 9 is adjusted for opening and closing according to the ash accumulation. Its structure is simple, with no mechanical transmission parts, ensuring reliable operation, easy processing, and low manufacturing cost. Routine operation and maintenance do not require furnace shutdown, and maintenance does not require the removal of any furnace wall, resulting in short maintenance time and low costs.

Claims

1. An external ash circulation system for a dual-bed internal circulating fluidized bed boiler, characterized in that: The ash circulation system is installed on the furnace walls on the left and right sides of the furnace of the double-bed internal circulating fluidized bed boiler, including the circulating ash channel (1), inspection door (2), ash cleaning hole (3), primary ash discharge pipe (4), primary ash discharge valve (5), fully automatic injection suction ash return system (6), observation hole (7), secondary ash discharge pipe (8), and secondary ash discharge valve (9). The bottom of the circulating ash channel (1) is connected to the inlet of the primary ash discharge pipe (4). The outlet end of the primary ash discharge pipe (4) is the primary ash discharge valve (5). The primary ash discharge valve (5) is connected to the top of one side of the fully automatic jet suction ash return system (6). The bottom of one side of the fully automatic jet suction ash return system (6) is connected to the secondary ash discharge pipe (8) and the secondary ash discharge valve (9). The other side of the fully automatic jet suction ash return system (6) is embedded in the furnace wall and connected to the furnace.

2. The external ash circulation system for a dual-bed internal circulating fluidized bed boiler as described in claim 1, characterized in that: The bottom of the circulating ash channel (1) is designed to be wider than 400mm and is equipped with an inspection door (2).

3. The external ash circulation system for a dual-bed internal circulating fluidized bed boiler as described in claim 1, characterized in that: The side of the circulating ash channel (1) is provided with a cleaning hole (3).

4. The external ash circulation system for a dual-bed internal circulating fluidized bed boiler as described in claim 1, characterized in that: The side of the fully automatic injection suction ash return system (6) is provided with an observation hole (7).

5. The external ash circulation system for a dual-bed internal circulating fluidized bed boiler as described in any one of claims 1-4, characterized in that: The ash circulation system is symmetrically arranged on the outer walls of the furnace on both the left and right sides of the furnace of the double-bed internal circulation fluidized bed boiler.

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