Device for catching fly ash in flue gas inlet volute of deacidification reaction tower
By installing ash guide channels and ash pipes inside the flue gas inlet volute, fly ash is guided into the desulfurization reaction tower, solving the problem of fly ash accumulation inside the flue gas inlet volute and achieving stable system operation and energy saving and emission reduction effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-08
- Publication Date
- 2026-03-24
AI Technical Summary
In the deacidification reaction tower of a waste incineration power plant, fly ash tends to accumulate in the flue gas inlet volute, leading to a reduction in flow area and an increase in resistance, which affects the stable operation of the system. Furthermore, the cleaning work is tedious and time-consuming.
An ash guide channel and an ash pipe are installed inside the flue gas inlet volute. The fly ash is guided into the desulfurization reaction tower through the guide channel. The design of the ash guide belt and the ash pipe ensures that the fly ash enters the reaction tower smoothly for storage and avoids accumulation inside the volute.
It extends the continuous operating time of the desulfurization system, reduces the power plant's power consumption, improves operational efficiency, and simplifies the fly ash cleaning process.
Smart Images
Figure CN224024697U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to an environmental protection device, especially fly ash capturing device installed in the fly ash inlet volute inside of the deacidification reaction tower on the top of SDA semi-dry deacidification reaction tower of garbage incineration power plant. BACKGROUND
[0002] With the people's environmental protection consciousness strengthens unceasingly, garbage incineration power generation project has been as the main way of garbage disposal, and as the main emission index of garbage incineration power plant SO2, HCl and other acid gas emissions are the data that people pay special attention to. The garbage incineration power generation project that has been built or newly built at present, the main deacidification process is to adopt the SDA semi-dry deacidification system of high-speed rotating atomizer, and the deacidification system can be long-time stable operation, which is the key measure for garbage incineration power plant to meet the emission requirements, and is the effective guarantee for power plant to increase operation benefit.
[0003] The high-temperature flue gas generated by the garbage incinerator is used for waste heat boiler power generation, and then enters the deacidification reaction tower from the flue gas inlet volute installed on the top of the deacidification reaction tower, and then enters the deacidification reaction tower from top to bottom for treatment. In the long-time operation process of the deacidification reaction tower system, the fly ash in the flue gas is easily accumulated on the inside bottom of the outer wall of the volute under the double actions of gravity and centrifugal force, which reduces the flue gas flow area in the volute, increases the resistance in the volute, and increases the power consumption of the induced draft fan. The accumulated fly ash in the flue gas inlet volute needs to be cleaned up during shutdown, and the cleaning process is troublesome and labor-intensive. UTILITY MODEL CONTENTS
[0004] The utility model discloses a fly ash capturing device in the flue gas inlet volute on the top of the deacidification reaction tower, which can speed up the discharge of fly ash in the flue gas inlet volute and ensure the long-time stable operation of the high-speed rotating atomization semi-dry deacidification system.
[0005] The utility model provides a technical scheme:
[0006] A fly ash capturing device in the flue gas inlet volute of the deacidification reaction tower, characterized in that the device comprises at least one fly ash guide channel arranged on the bottom surface of the flue gas inlet volute and a fly ash pipe connected with the fly ash guide channel and guiding the fly ash into the deacidification reaction tower; the fly ash guide channel is formed by the bottom surface of the flue gas inlet volute, a fly ash guide belt vertically arranged on the bottom surface of the flue gas inlet volute and the inner wall of the outer circumference of the flue gas inlet volute; the inlet end of the fly ash pipe is connected with the end of the fly ash guide channel, and the outlet end extends downward through the internal partition plate of the flue gas inlet volute into the deacidification reaction tower.
[0007] The ash guide belt is composed of a square tube fixed at the bottom of the inlet channel of the flue gas inlet volute, a circular tube parallel to the square tube and fixed at the upper edge of the square tube, and a conical plate vertically embedded between the square tube and the circular tube.
[0008] The width of the horizontal projection of the ash guide channel gradually narrows along the direction of flue gas movement to match the inner diameter of the ash pipe.
[0009] The height of the ash guide belt gradually decreases along the direction of flue gas movement to match the inner diameter of the ash pipe.
[0010] The length of the conical plate is one-half to three-fourths of the length of the square tube; the length of the circular tube is greater than the length of the conical plate and less than the length of the square tube.
[0011] The starting end of the ash guide belt includes the square tube, the conical plate, and the circular tube.
[0012] The end of the circular tube is directly fixed at the top end of the square tube.
[0013] The beneficial effects of the utility model are that: the device can be accurately installed at the main accumulation position inside the inlet volute, thereby guiding most of the fly ash originally retained in the inlet volute into the deacidification reaction tower, prolonging the continuous operation time of the entire deacidification system by 2-3 times, increasing the energy-saving and emission-reducing effect, and increasing the operation benefit of the power plant. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is a schematic diagram of the installation position of the utility model embodiment 1 in the flue gas inlet volute (front view).
[0015] Figure 2 is a schematic diagram of the top view structure of the utility model embodiment 1 in the flue gas inlet volute (the dashed line is the outline of the flue gas inlet volute).
[0016] Figure 3 is a schematic diagram of the unfolded state of the ash guide belt in the utility model embodiment 1.
[0017] Figure 4 is Figure 2 A-A direction in the schematic diagram.
[0018] Figure 5 is a schematic diagram of the three-dimensional structure of the flue gas inlet volute in the utility model embodiment 2 (bottom).
[0019] Figure 6 is a schematic diagram of the installation position of the utility model embodiment 2 in the flue gas inlet volute (front view).
[0020] Figure 7is one of the computer fly ash flow field concentration simulation diagram (high concentration state).
[0021] Figure 8 is the second computer fly ash flow field concentration simulation diagram (low concentration state).
[0022] The figure label: 1, flue gas import volute, 2, ash guide belt, 2-1, square tube, 2-2, round tube, 2-3, conical plate, 3, ash pipe, 4, import passage, 5 flue gas outlet. DETAILED DESCRIPTION
[0023] Example 1
[0024] As Figure 1 , Figure 4 shown, the funnel-shaped flue gas import volute 1 is installed at the top of the deacidification reaction tower, the import passage 4 of the volute is located in the tangent direction of the volute outer circumferential surface, and the annular outlet 5 formed by the inner and outer sleeves is located at the bottom end of the volute center; the flue gas to be treated is sprayed into the import passage of the volute to form a rotating airflow, and then enters the deacidification reaction tower from the flue gas outlet; most of the fly ash in the flue gas is collected in the middle of the volute along with the rotating flue gas, and then discharged into the deacidification reaction tower through the flue gas outlet, and finally stored in the fly ash bin; a small amount of fly ash will be retained and accumulated on the bottom surface of the import passage of the volute, and the accumulation will increase over time. The above is the structure of the existing flue gas import volute.
[0025] Due to the defect that the existing flue gas import volute structure is not easy to clean up the accumulated fly ash, the inventor makes the following changes:
[0026] First, a fly ash capture flue is arranged in the import passage of the flue gas import volute, and computer fly ash flow field concentration simulation is performed on the fly ash in the import passage of the existing flue gas import volute to determine the best position of the fly ash capture flue.
[0027] The specific way is:
[0028] In order to intuitively determine the fly ash flow field concentration in the flue gas import volute, CFD flow field simulation concentration simulation (prior art) is adopted to provide a basis for determining the best position of the fly ash capture flue. Among them, Figure 7 , Figure 8 respectively show the flow field simulation effect of the flue gas distribution of the fly ash particles in the flue gas import volute under two different concentration conditions, the red area in the figure is high concentration flue gas, the cyan area is medium concentration flue gas, and the blue area is low concentration flue gas.
[0029] Obviously, according to the simulation effect, the best position of the fly ash capture flue should be set at the end of the red part.
[0030] Second, the structure of the fly ash capture flue is determined.
[0031] The fly ash collection flue provided by the utility model is set, including the ash falling guide channel laid on the bottom surface of the inlet channel of the flue gas inlet volute and the ash falling pipe connected with the ash falling guide channel; the ash falling guide channel is formed by the bottom surface of the inlet channel of the flue gas inlet volute, the ash falling guide belt 2 vertically laid on the bottom surface of the inlet channel of the flue gas inlet volute and the inner wall of the outer circumferential surface of the flue gas inlet volute; the width of the horizontal plane projection of the ash falling guide channel gradually narrows along the flue gas movement direction, and finally is suitable for the diameter of the ash falling pipe; the height of the ash falling guide belt also gradually decreases along the flue gas movement direction, and finally is suitable for the diameter of the ash falling pipe. The inlet end of the ash falling pipe is connected with the tail end of the ash falling guide channel, and the outlet end extends to the deacidification reaction tower through the internal partition plate of the flue gas inlet volute, so that the fly ash collected by the ash falling guide channel is drained into the deacidification reaction tower. Then, the fly ash captured in the flue gas can be conveyed to the fly ash storage through the ash unloading valve at the bottom of the reaction tower and the conveyor.
[0032] Further, in order to avoid affecting the rotating airflow in the flue gas inlet volute, the ash falling guide belt is high first and then low along the airflow direction (see the partial view shown in Figure 3 and the expanded view shown in Figure 4 ), which is composed of the square tube 2-1 fixed on the bottom surface of the inlet channel of the flue gas inlet volute, the circular tube 2-2 parallel to the square tube and fixed on the upper edge of the square tube and the conical plate 2-3 vertically embedded between the square tube and the circular tube (recommended to be welded). The starting end (close to the flue gas inlet end) of the ash falling guide belt includes the square tube, the conical plate and the circular tube, the length of the conical plate is one half to three quarters of the length of the square tube; the length of the circular tube is greater than the length of the conical plate and less than the length of the square tube, so that the tail end of the circular tube is directly fixed on the top end of the square tube.
[0033] The diameter of the ash falling pipe is suitable for the size of the ash falling guide channel, so that the fly ash flowing out of the ash falling guide channel can be effectively received.
[0034] Example 2
[0035] As shown in Figure 5 , Figure 6 ; the difference between this embodiment and example 1 is that two fly ash collection flues are arranged, which are arranged on the bottom surface of the inlet channel of the flue gas inlet volute (shown in Figure 8 : the arrangement position is in the second and third quadrants with the flue gas inlet volute axis as the center); one of the fly ash collection flues is arranged in the fly ash gathering area (i.e. the red area in the simulation flow field simulation diagram); the other fly ash collection flue is designed on the rear side of the previous fly ash collection flue, which mainly captures the remaining fly ash. The structure of each fly ash collection flue is the same as that of example 1.
[0036] This embodiment is mainly used for the project with large flue gas treatment capacity.
Claims
1. A fly ash capture device inside the flue gas inlet casing of a deacidification reaction tower, characterized in that: The device comprises at least one ash falling guide channel arranged at the bottom surface of the flue gas inlet volute inlet channel and an ash falling pipe (3) connected with the ash falling guide channel to guide the fly ash into the deacidification reaction tower; the ash falling guide channel is formed by the bottom surface of the flue gas inlet volute inlet channel, the ash falling guide belt vertically arranged at the bottom surface of the flue gas inlet volute inlet channel and the outer circumferential surface inner wall of the flue gas inlet volute; the inlet end of the ash falling pipe is connected with the end of the ash falling guide channel, and the outlet end extends downward through the internal partition plate of the flue gas inlet volute to the deacidification reaction tower.
2. The fly ash capturing device inside the flue gas inlet volute of deacidifying reaction tower according to claim 1, characterized in that: The ash falling guide belt is composed of a square tube (2-1) fixed at the bottom surface of the flue gas inlet volute inlet channel, a circular tube (2-2) fixed on the top of the square tube and parallel to the square tube and a conical plate (2-3) vertically embedded between the square tube and the circular tube.
3. The fly ash capturing device inside the inlet volute of flue gas of deacidifying reaction tower according to claim 2, characterized in that: The width of the horizontal projection of the ash falling guide channel gradually narrows along the direction of flue gas movement to be suitable for the inner diameter of the ash falling pipe.
4. The fly ash capturing device inside the inlet volute of flue gas of deacidifying reaction tower according to claim 3, characterized in that: The height of the ash falling guide belt gradually decreases along the direction of flue gas movement to be suitable for the inner diameter of the ash falling pipe.
5. The fly ash capturing device inside the inlet volute of flue gas of deacidifying reaction tower according to claim 4, characterized in that: The length of the conical plate is one half to three quarters of the length of the square tube; the length of the circular tube is greater than the length of the conical plate and less than the length of the square tube.
6. The fly ash capturing device inside the inlet volute of flue gas of deacidifying reaction tower according to claim 5, characterized in that: The starting end of the ash falling guide belt comprises the square tube, the conical plate and the circular tube.
7. The fly ash capturing device inside the inlet volute of flue gas of deacidifying reaction tower according to claim 6, characterized in that: The end of the circular tube is directly fixed at the top end of the square tube.