A circulating fluidized bed boiler waste stone powder speed-up injection device

Abstract

The utility model discloses a kind of circulating fluidized bed boiler waste stone powder speed-up injection devices;Belong to boiler waste stone powder adding technical field;Its technical key points include the material injection pipe being set on furnace hearth pipeline, the booster pipe with the diameter less than material injection pipe is connected by flange at the place of material injection pipe close to pipeline, both ends before and after booster pipe are equipped with the horn mouth connected with material injection pipe;The outlet end of booster pipe is equipped with the auxiliary blowing component that blows to furnace hearth pipeline place;The utility model aims at providing a kind of circulating fluidized bed boiler waste stone powder speed-up injection device with simple structure, powder spraying power is sufficient;For adding waste stone powder to circulating fluidized bed boiler.

Description

Technical Field

[0001] This utility model relates to a waste rock powder acceleration injection device, and more specifically, to a waste rock powder acceleration injection device for a circulating fluidized bed boiler. Background Technology

[0002] Currently, circulating fluidized bed boilers use waste rock powder injected into the furnace for desulfurization to reduce SO2 emissions in flue gas. Waste rock powder refers to a mixture of various materials such as dolomite, quartz, and coal gangue that has been ground into powder, with a calcium oxide content of about 40%.

[0003] Waste stone powder is quantitatively injected into the waste stone powder pipeline injector in front of the furnace via a screw feeder. The waste stone powder is then blown into the furnace by airflow generated by a waste stone powder blower. To control ultra-low emissions, our company installed a T-junction on the waste stone powder pipeline and added a boiler powder injection channel, adjusting the amount of waste stone powder used and reducing the amount of waste stone powder mixed in, thereby reducing the cost of purchasing waste stone powder. However, during production, it was found that when the boiler powder injection channel was added, the airflow carrying the powder was diverted through the T-junction, resulting in a corresponding decrease in airflow power. This led to insufficient power in the ejected powder, affecting the uniform distribution of waste stone powder in the furnace and reducing the boiler's desulfurization efficiency. Utility Model Content

[0004] The purpose of this utility model is to address the shortcomings of the prior art by providing a circulating fluidized bed boiler waste stone powder acceleration injection device with a simple structure and sufficient powder injection power.

[0005] The technical solution of this utility model is implemented as follows: a waste rock powder acceleration injection device for a circulating fluidized bed boiler includes a spray pipe installed on the furnace pipe. A pressure pipe with a diameter smaller than the spray pipe is connected to the spray pipe via a flange near the pipe. A bell mouth connected to the spray pipe is provided at both ends of the pressure pipe. An air-blowing component is provided at the outlet end of the pressure pipe to blow air towards the furnace pipe.

[0006] In the aforementioned circulating fluidized bed boiler waste rock powder acceleration injection device, a multi-hole pressure booster is provided on the injection pipe between the blowing aid component and the furnace pipe via a flange, and the total flow area of ​​the multi-hole pressure booster is smaller than the inner diameter of the injection pipe.

[0007] In the aforementioned circulating fluidized bed boiler waste rock powder acceleration injection device, the porous booster includes an installation pipe connected to the flange of the injection pipe. The inner diameter of the installation pipe is smaller than that of the injection pipe. A funnel-shaped transition section is provided at the end where the installation pipe connects to the injection pipe. Several baffles are provided inside the installation pipe. The baffles cooperate to form a grid and divide the installation pipe into several small-diameter acceleration pipes. A tapered clearance section is provided at the end of the baffle near the injection pipe.

[0008] In the aforementioned circulating fluidized bed boiler waste rock powder acceleration injection device, the blowing aid assembly includes a uniform air ring disposed outside the pressurization pipe, the uniform air ring being connected to an external air source through an air supply pipe; a plurality of blowing aid pipes communicating with the pressurization pipe are evenly distributed circumferentially on the uniform air ring, the blowing aid pipes being inclinedly disposed on the side wall of the pressurization pipe.

[0009] In the aforementioned circulating fluidized bed boiler waste rock powder acceleration injection device, the included angle α between the blowing tube and the pressurization tube is 15-20°.

[0010] With the above-described structure, the reduced aperture area of ​​the airflow through the booster pipe increases the air pressure and improves the gas velocity. This provides sufficient conveying power for the waste stone powder to be injected into the furnace pipe, improving the uniformity of waste stone powder distribution within the furnace. Simultaneously, the addition of an auxiliary blowing component further increases the gas flow rate and accelerates the powder carried in the airflow, providing even more power. Attached Figure Description

[0011] The present invention will be further described in detail below with reference to the embodiments shown in the accompanying drawings, but this does not constitute any limitation on the present invention.

[0012] Figure 1 This is a schematic diagram of the structure of this utility model;

[0013] Figure 2 This is a partial structural diagram of point A of this utility model;

[0014] Figure 3 This is a schematic diagram of the structure of the multi-hole booster of this utility model;

[0015] Figure 4 This is a cross-sectional structural diagram of the porous booster of this utility model.

[0016] In the diagram: 1. Spray pipe; 2. Pressure booster pipe; 3. Nozzle; 4. Auxiliary blowing assembly; 4a. Air distribution ring; 4b. Air delivery pipe; 4c. Auxiliary blowing pipe; 5. Multi-hole pressure booster; 5a. Installation pipe; 5b. Transition section; 5c. Baffle plate; 5d. Conical clearance section. Detailed Implementation

[0017] See Figure 1-4 As shown, this utility model discloses a waste rock powder acceleration injection device for a circulating fluidized bed boiler. It includes a spray pipe 1 installed on the furnace pipeline. A pressure boosting pipe 2 with a smaller diameter than the spray pipe 1 is connected to the spray pipe 1 via a flange near the pipeline. Both ends of the pressure boosting pipe 2 are provided with bell-shaped openings 3 connected to the spray pipe 1. The spray pipe is connected to an external screw feeder and jetting equipment for powder input. A heat dissipation coil is installed on the spray pipe at the material inlet end. When the spray pipe is connected to the boiler return air pipeline for air supply, the heat dissipation coil reduces the heat of the gas, improving safety.

[0018] The smaller diameter booster pipe and the flared ends form a Venturi tube structure. When the airflow passes through the booster pipe, the reduced aperture area increases the air pressure and improves the gas velocity, enabling the waste stone powder to have sufficient conveying power to be injected into the furnace pipe, thereby improving the uniformity of the waste stone powder distribution in the furnace.

[0019] At the same time, when the powder enters the spray pipe after passing through the pressurization pipe, it can be concentrated in the center of the spray pipe, reducing the friction between the powder and the inner wall of the spray pipe, and reducing the loss of kinetic energy.

[0020] The outlet end of the booster pipe 2 is equipped with a blowing aid component 4 that blows air towards the furnace pipe. By setting up the blowing aid component, the gas flow rate is increased and the powder carried in the airflow is accelerated in advance, further providing sufficient power.

[0021] In this embodiment, preferably, a multi-hole pressure booster 5 is provided on the injection pipe 1 between the blowing aid assembly 4 and the furnace pipe via a flange. The total flow area of ​​the multi-hole pressure booster 5 is smaller than the inner diameter of the injection pipe 1. The specific ratio can be determined according to requirements and can be achieved by changing the orifice diameter, etc. As the orifice diameter decreases, the number of vanes forming holes inside increases, and the flow area decreases accordingly. When the airflow passes through the multi-hole pressure booster, the reduced orifice area increases the air pressure and increases the gas velocity. At the same time, the multiple small-hole pipes can disperse the powder while accelerating it, which can effectively improve the uniformity of the waste stone powder distribution in the furnace.

[0022] More preferably, the multi-hole booster 5 includes an installation pipe 5a connected to the flange of the spray pipe 1. The inner diameter of the installation pipe 5a is smaller than that of the spray pipe 1. A funnel-shaped transition portion 5b is provided at the end of the installation pipe 5a connected to the spray pipe 1. Several baffles 5c are provided inside the installation pipe 5a. The baffles 5c cooperate to form a grid and divide the installation pipe 5a into several small-diameter booster pipes. A tapered clearance portion 5d is provided at the end of the baffle 5c near the spray pipe 1. The transition portion allows the gas carrying the powder to smoothly enter the small-diameter installation pipe from the large-diameter spray pipe, avoiding obstruction and deceleration of the gas at the end.

[0023] The total cross-sectional area of ​​all speed-up pipes inside the installation pipe is no more than two-thirds of the cross-sectional area of ​​the spray pipe. When the airflow reaches the front end of the speed-up pipe, the gas pressure will increase due to the small aperture and continuous subsequent gas delivery. Then the gas is squeezed from the large pipe into each speed-up pipe, which increases the airflow velocity.

[0024] A tapered clearance section is provided on the end of the partition plate near the material inlet direction to reduce the collision volume between the gas and the end face of the partition plate, so that the gas can smoothly enter the acceleration pipe between the partition plates to increase acceleration and avoid collision with the front end of the partition plate, which would slow down the powder carried in the gas.

[0025] In this embodiment, the blowing aid assembly 4 includes an air distribution ring 4a disposed outside the pressurization pipe 2, which is connected to an external air source via an air supply pipe 4b. Several blowing aid pipes 4c, communicating with the pressurization pipe 2, are evenly distributed circumferentially on the air distribution ring 4a. These blowing aid pipes 4c are inclinedly disposed on the side wall of the pressurization pipe 2. By blowing air towards the center of the pressurization pipe through the inclined blowing aid pipes, the powder is accelerated and concentrated towards the center, reducing friction between the powder and the inner wall of the spray pipe, thus further reducing kinetic energy loss.

[0026] In this embodiment, preferably, the included angle α between the blowing aid pipe 4c and the booster pipe 2 is 15-20°. Multiple experiments have shown that when the included angle α is 15-20°, the airflow ejected from the blowing aid pipe can sufficiently accelerate the powder without blowing it onto the inner wall of the pipe on the opposite side, ensuring that the powder is conveyed forward.

[0027] During operation, the external screw feeder and jetting equipment input the powder into the injection pipe. The airflow carrying the powder enters the pressurization pipe for initial pressurization and acceleration. When the airflow approaches the outlet end of the pressurization pipe, it is propelled by the jetting from the auxiliary blowing pipe for a second acceleration. After the initial acceleration is completed, the airflow continues to advance along the injection pipe and enters the small-diameter pipe on the mounting pipe for further pressurization and acceleration. After acceleration is completed, the gas carrying the powder returns from the outlet end of the mounting pipe to the injection pipe and is injected into the furnace pipe.

[0028] The above-described embodiments are preferred embodiments of the present utility model and are only used to facilitate the illustration of the present utility model. They are not intended to limit the present utility model in any way. Any person skilled in the art who makes partial modifications or alterations to the technical content disclosed in the present utility model without departing from the scope of the technical features of the present utility model shall still fall within the scope of the technical features of the present utility model.

Claims

1. A waste rock powder acceleration injection device for a circulating fluidized bed boiler, comprising an injection pipe (1) installed on the furnace pipeline, characterized in that, The spray pipe (1) is connected to a pressure pipe (2) with a diameter smaller than that of the spray pipe (1) via a flange near the pipeline. Both ends of the pressure pipe (2) are provided with flared mouths (3) connected to the spray pipe (1). The outlet end of the pressure pipe (2) is provided with a blowing aid assembly (4) that blows air toward the furnace pipeline.

2. The waste rock powder acceleration injection device for a circulating fluidized bed boiler according to claim 1, characterized in that, A multi-hole pressure booster (5) is provided on the injection pipe (1) between the blowing aid assembly (4) and the furnace pipe via a flange. The total flow area of ​​the multi-hole pressure booster (5) is smaller than the inner diameter of the injection pipe (1).

3. The waste rock powder acceleration injection device for a circulating fluidized bed boiler according to claim 2, characterized in that, The multi-hole booster (5) includes an installation pipe (5a) connected to the flange of the spray pipe (1), the inner diameter of the installation pipe (5a) being smaller than that of the spray pipe (1), and a flared transition section (5b) at one end of the installation pipe (5a) connected to the spray pipe (1); a plurality of baffles (5c) are provided inside the installation pipe (5a), the baffles (5c) cooperating to form a grid and dividing the installation pipe (5a) into a plurality of small-diameter speed-boosting pipes; a tapered relief section (5d) is provided at one end of the baffle (5c) near the spray pipe (1). The total cross-sectional area of ​​all speed-up pipes within the installation pipe shall not exceed two-thirds of the cross-sectional area of ​​the spray pipe.

4. The waste rock powder acceleration injection device for a circulating fluidized bed boiler according to claim 1, characterized in that, The blowing aid assembly (4) includes a uniform air ring (4a) disposed on the outside of the booster pipe (2), the uniform air ring (4a) being connected to an external air source through an air supply pipe (4b); a number of blowing aid pipes (4c) communicating with the booster pipe (2) are evenly distributed along the circumference on the uniform air ring (4a), and the blowing aid pipes (4c) are inclinedly disposed on the side wall of the booster pipe (2).

5. The waste rock powder acceleration injection device for a circulating fluidized bed boiler according to claim 4, characterized in that, The included angle α between the blow-in pipe (4c) and the pressurization pipe (2) is 15-20°.

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