Sludge injection device

Abstract

The present invention discloses a sludge injection device. When the sludge moves to the outlet pipe section, the sludge channel becomes narrower due to the setting of the guide cone, the sludge flow rate will become faster, and the sludge will be injected from the channel between the guide cone and the sludge injection pipe to the outside, that is, the sludge is injected circumferentially close to the sludge injection pipe. Under the action of the nozzle ejection airflow, the sludge is more easily reasonably dispersed at the outlet and enters the furnace for combustion, thereby improving the combustion efficiency. In addition, after the compressed gas is ejected from the nozzle, a swirling airflow is formed, which can increase the turbulence of the atomized sludge, so that the wet sludge is fully mixed with the compressed air. At the same time, the tangential rotation speed of the atomized sludge will accelerate the attenuation of the axial injection speed of the atomized sludge, thereby reducing the injection distance of the atomized sludge, and can effectively prevent the atomized sludge from adhering to the water-cooled wall of the opposite furnace, thereby preventing the water-cooled wall from coking and corrosion.

Description

Technical Field

[0001] The invention relates to the technical field of sludge treatment, and in particular to a sludge injection device. Background Art

[0002] With the rapid development of my country's economy, the level of urbanization has been continuously improved, and the amount of urban sludge has increased significantly. Traditional sludge treatment methods such as landfill and composting have the disadvantages of large land area and long service life, while sludge incineration has the advantages of reduction, harmlessness, resource utilization and stabilization, which has great promotion significance. The use of stable and fuel-adaptable circulating fluidized bed, garbage incinerator or grate furnace boilers to mix wet sludge can achieve sludge reduction while using the flue gas treatment device at the tail of the boiler to coordinately treat the flue gas generated by sludge incineration to meet environmental protection requirements. It is more competitive in terms of economy and technology.

[0003] In the existing wet sludge incineration disposal scheme, the following two methods are generally used: one is to directly mix the wet sludge with the original boiler fuel and then transport it into the boiler for combustion. This mixing method is an open mixing method, which may cause the leakage and diffusion of sludge odor and pollute the nearby environment. The other is that the wet sludge enters the sludge spray gun through the pumping system and is then sprayed into the furnace. This sludge spray gun is generally composed of sludge pipes, compressed air pipes, etc. Through the high pressure of the pumping system and compressed air, the sludge is atomized and sprayed into the furnace for combustion.

[0004] The sludge spray gun has the advantages of being airtight, having no odor leakage, having a simple system, and having a low investment cost. However, during operation, the existing sludge spray gun adheres the sludge to the water-cooled wall of the furnace due to the excessively high injection speed during the sludge atomization process, resulting in a risk of coking and a large amount of compressed air used. The amount of air entering the furnace is too large, affecting the combustion control of the boiler system.

[0005] How to prevent sludge from adhering to the water-cooled wall of the furnace and improve the sludge combustion efficiency is a technical problem that needs to be solved urgently by technicians in this field. Summary of the invention

[0006] The object of the present invention is to provide a sludge injection device which can prevent sludge from adhering to the water-cooled wall of the furnace and improve the sludge combustion efficiency.

[0007] The present invention provides a sludge injection device, comprising a sludge injection pipe, a compressed air pipe and a guide cone, wherein the guide cone is installed at the outlet pipe section of the sludge injection pipe, and the closer to the pipe mouth, the smaller the distance between the guide cone and the corresponding sludge injection pipe; the outlet pipe section is also provided with at least three nozzles connected to the compressed air pipe, and the air flow outlet direction of the nozzle has an angle with the radial direction that can at least form a rotary airflow at the outlet of the outlet pipe section.

[0008] When the sludge injection device provided by the present invention is used, the sludge is pumped to the sludge injection pipe through the pumping component. When the sludge moves to the outlet pipe section, the sludge channel becomes narrower due to the setting of the guide cone, the sludge flow rate will become faster, and the sludge will be injected from the channel between the guide cone and the sludge injection pipe to the outside, that is, the sludge is injected circumferentially close to the sludge injection pipe. Under the action of the nozzle ejection airflow, the sludge is more easily reasonably dispersed at the outlet and enters the furnace for combustion, thereby improving the combustion efficiency. In addition, the compressed gas is ejected from the nozzle to form a swirling airflow, which can increase the turbulence of the atomized sludge, so that the wet sludge is fully mixed with the compressed air. At the same time, the tangential rotation speed of the atomized sludge will accelerate the attenuation of the axial injection speed of the atomized sludge, thereby reducing the injection distance of the atomized sludge, and can effectively prevent the atomized sludge from adhering to the water-cooled wall of the opposite furnace, thereby preventing the water-cooled wall from coking and corrosion.

[0009] Optionally, the nozzles are evenly arranged along the circumferential direction, and the radial angle between the airflow outlet direction of the nozzles and the sludge injection pipe is in a range of 35° to 65°.

[0010] Optionally, it also includes a first cooling air duct, which is mounted on the outside of the sludge injection pipe, and a first fluid channel is formed between the first cooling air duct and the sludge injection pipe. The outlet end of the first fluid channel close to the sludge injection pipe is an open structure, and the other end is a closed structure. The outlet end of the sludge injection pipe is completely located inside the first cooling air duct or the outlet end of the sludge injection pipe is flush with the open end of the first cooling air duct.

[0011] Optionally, it also includes a second cooling air duct, which is at least partially sleeved on the outside of the first cooling air duct, and a second fluid channel is formed between the second cooling air duct and the first cooling air duct, the second fluid channel is an open structure at the outlet end close to the sludge injection pipe, and the other end is a closed structure, the outlet end of the first cooling air duct is completely located inside the second cooling air duct or the open end of the first cooling air duct is flush with the outlet end of the sludge injection pipe.

[0012] Optionally, it also includes guide blades installed on the second fluid channel, which are used to form a rotational airflow at the outlet end of the second fluid channel, and the guide blades are evenly arranged along the circumferential direction, and the rotation direction of each guide blade is consistent with the rotation direction of the nozzle to form an airflow with the same rotation direction.

[0013] Optionally, it also includes a conical expansion pipe, which is connected to the outlet end of the second cooling air duct, and the diameter of the conical expansion pipe gradually increases along the air flow direction, wherein the expansion angle range of the conical expansion pipe is 15° to 30°, and the length is 0.6 to 0.75 times the diameter of the sludge injection pipe.

[0014] Optionally, the compressed air pipe includes a main pipe and several branch pipes, the main pipe is sleeved on the outside of a partial pipe section of the sludge injection pipe, and the main pipe and the first cooling air duct are arranged in sequence along the air flow direction, a compressed gas channel is formed between the main pipe and the sludge injection pipe, the main pipe includes an inlet and an outlet connected through the compressed gas channel, the inlet is used to connect to an external air source, one end of each branch pipe is connected to the outlet, and the other end passes through the first fluid channel to connect to the nozzle.

[0015] Optionally, the outlets of the main pipe are evenly spaced along the circumferential direction, and the branch pipes, the outlets of the main pipe and the nozzles correspond one to one.

[0016] Optionally, it also includes a first regulating valve, a second regulating valve and a third regulating valve, which are respectively used to regulate the gas flow entering the compressed air pipe, the first fluid channel and the second fluid channel.

[0017] Optionally, the maximum end diameter of the guide cone is 0.35 to 0.5 times the diameter of the pipe at a corresponding position of the outlet pipe section. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a sludge injection device in one embodiment of the present invention;

[0019] Figure 2 It is a partial cross-sectional schematic diagram of a sludge injection device in one embodiment of the present invention;

[0020] Figure 3 It is a schematic axial cross-sectional view of a sludge injection device in one embodiment of the present invention;

[0021] Figure 4 for Figure 1 A side view of the sludge injection device;

[0022] Figure 5 It is a partial perspective view of a sludge injection device in one embodiment of the present invention.

[0023] in, Figures 1 to 5 The one-to-one correspondence between the reference numerals and the component names is as follows:

[0024] 1 sludge injection pipe; 2 compressed air pipe; 21 main pipe; 22 branch pipe; 2a compressed air inlet pipe; 3 first cooling air pipe; 4 second cooling air pipe; 3a first fluid inlet pipe; 2b compressed gas channel; 3b first fluid channel; 4b second fluid channel; 4a second fluid inlet pipe; 5 nozzle; 6 guide vane; 7 conical expansion pipe; 8 guide cone; 9 cleaning component; 10 sludge stop valve; 11 first regulating valve; 12 second regulating valve; 13 third regulating valve; 14 bracket. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] Please refer to Figures 1 to 5 , Figure 1 It is a structural schematic diagram of a sludge injection device in one embodiment of the present invention; Figure 2 It is a partial cross-sectional schematic diagram of a sludge injection device in one embodiment of the present invention; Figure 3 It is a schematic axial cross-sectional view of a sludge injection device in one embodiment of the present invention; Figure 4 for Figure 1 A side view of the sludge injection device; Figure 5 It is a partial perspective view of a sludge injection device in one embodiment of the present invention.

[0027] The present invention provides a sludge injection device, which includes a sludge injection pipe 1, a compressed air pipe 2 and a guide cone 8. The sludge injection device provided herein can be applied to a sludge injection gun, and of course can also be applied to other mechanisms. This article takes the application of the sludge injection device to the sludge injection gun as an example to continue to introduce the technical solution and technical effects.

[0028] Among them, the guide cone 8 is installed on the outlet pipe section of the sludge injection pipe 1. The closer to the pipe outlet, the smaller the distance between the guide cone and the corresponding sludge injection pipe 1; that is, the closer the guide cone is to the outlet of the sludge injection pipe 1, the larger the cross-sectional size of the guide cone is, that is, along the flow direction of the fluid, the cross-sectional size of the guide cone gradually increases. In order to minimize the resistance of the guide cone to the fluid, the outer peripheral surface of the guide cone can be a conical surface, of course, other forms are not excluded. The guide cone 8 can be supported in the middle position of the sludge injection pipe 1 by a bracket 14. The form of the bracket 14 is not limited, as long as it does not affect the injection of the sludge and provides reliable support for the guide cone.

[0029] The outlet pipe section of the sludge injection pipe 1 is also provided with at least three nozzles 5 connected to the compressed air pipe 2, and the airflow outlet direction of the nozzle 5 has an angle with the radial direction that can form a swirling airflow at least at the outlet of the outlet pipe section. In other words, the airflow outlet direction of the nozzle 5 has a predetermined angle with the radial direction of the sludge injection pipe 1, which can form a swirling airflow at the outlet position of the sludge injection pipe 1 after the compressed airflow is ejected from the nozzle 5. The number of nozzles 5 can be three, or four or more. In a specific embodiment, 6 to 8 nozzles 5 are arranged along the circumferential direction to achieve a stable swirling airflow.

[0030] When the sludge injection device provided by the present invention is used, the sludge is pumped to the sludge injection pipe 1 through the pumping component. When the sludge moves to the outlet pipe section, the sludge channel becomes narrower due to the setting of the guide cone 8, the sludge flow rate will become faster, and the sludge will be injected from the channel between the guide cone and the sludge injection pipe 1 to the outside, that is, the sludge is ejected circumferentially close to the sludge injection pipe 1. Under the action of the airflow ejected by the nozzle 5, the sludge is more easily reasonably dispersed at the outlet and enters the furnace for combustion, thereby improving the combustion efficiency. In addition, the compressed gas is ejected from the nozzle 5 to form a swirling airflow, which can increase the turbulence of the atomized sludge, so that the wet sludge is fully mixed with the compressed air. At the same time, the tangential rotation speed of the atomized sludge will accelerate the attenuation of the axial injection speed of the atomized sludge, thereby reducing the injection distance of the atomized sludge, and can effectively prevent the atomized sludge from adhering to the water-cooled wall of the opposite furnace, thereby preventing the water-cooled wall from coking and corrosion.

[0031] In the above embodiment, the nozzles 5 are evenly arranged along the circumferential direction, and the radial angle between the airflow outlet direction of the nozzles 5 and the sludge injection pipe 1 is in the range of 35° to 65°. Practice has proved that the installation method of the nozzles 5 in the above embodiment allows the mixing of the swirling airflow and the wet sludge to be more sufficient.

[0032] The number of nozzles 5 may be determined according to the specific application environment. In a specific sludge injection gun, the number of nozzles 5 may be 4-8.

[0033] In a specific embodiment, the sludge injection device may further include a first cooling air duct 3, which is sleeved on the outside of the sludge injection pipe 1, and a first fluid channel 3b is formed between the first cooling air duct 3 and the sludge injection pipe 1. The outlet end of the first fluid channel 3b close to the sludge injection pipe 1 is an open structure, and the other end is a closed structure. The outlet end of the sludge injection pipe 1 is completely located inside the first cooling air duct 3 or the two are flush. This article provides a specific implementation method in which the outlet end of the sludge injection pipe 1 is flush with the open end of the first cooling air duct 3.

[0034] The first cooling air duct 3 cools the sludge but does not provide further power to the sludge at the injection port.

[0035] Furthermore, the sludge injection device in the above embodiment may also include a second cooling air duct 4, which is at least sleeved on the outside of a partial section of the first cooling air duct 3, and a second fluid channel 4b is formed between the second cooling air duct 4 and the first cooling air duct 3, and the second fluid channel 4b is an open structure at the outlet end close to the sludge injection pipe 1 and a closed structure at the other end, and the outlet end of the first cooling air duct 3 is completely located inside the second cooling air duct 4 or the open end of the first cooling air duct 3 is flush with the outlet end of the sludge injection pipe 1.

[0036] From the above description, it can be seen that in the above embodiment, a relatively independent first cooling air duct 3 and a second cooling air duct 4 are provided to form a relatively independent first fluid channel 3b and a second fluid channel 4b for the flow of different fluids, that is, the cooling airflow is divided into two independent levels, and the outlet airflow directions of the two fluids are controlled respectively, so as to achieve sufficient mixing of the gas and the wet sludge.

[0037] In the above embodiments, the sludge injection device may also include a guide blade 6 installed on the second fluid channel 4b, which is used to form a swirl airflow at the outlet end of the second fluid channel 4b. The guide blades 6 are evenly arranged along the circumference, and the swirl direction of each guide blade 6 is consistent with the swirl direction of the nozzle 5 to form an airflow with the same swirl direction. Through the graded cooling airflow supply and the rotation of the second fluid and its rotation direction is consistent with the rotation direction of the compressed air, the swirl airflow formed together can timely draw the high-temperature flue gas in the furnace into the atomized sludge injection range, so that the high-temperature flue gas and the sludge are fully mixed, the moisture of the atomized sludge is heated and evaporated, and the atomized sludge is burned in the furnace in a timely, rapid and sufficient manner, so as to achieve complete decomposition of sludge organic matter, increase the amount of sludge disposal, and reduce the impact of the sludge direct mixing system on the original boiler combustion.

[0038] Furthermore, the sludge injection device may further include a conical expansion pipe 7, which is connected to the outlet end of the second cooling air duct 4, and the diameter of the conical expansion pipe 7 gradually increases along the airflow direction. The expansion angle b of the conical expansion pipe 7 is in the range of 15° to 30°, and the so-called expansion angle is the angle between the generatrix and the axial direction in the longitudinal section of the conical expansion pipe 7. The length L of the conical expansion pipe 7 is 0.6 to 0.75 times the diameter of the sludge injection pipe 1.

[0039] The conical expansion pipe 7 can strengthen the swirl intensity of the external cooling wind and the compressed air, further strengthen the mixing degree of the compressed air and the wet sludge, strengthen the ability of the cooling wind to draw in the high-temperature furnace smoke, so that the wet sludge and the high-temperature furnace smoke are mixed in time and fully, the wet sludge diffuses widely in the furnace, and burns quickly.

[0040] In the above embodiments, the compressed air pipe 2 includes a main pipe 21 and a plurality of branch pipes 22. The main pipe 21 is sleeved on the outside of a portion of the sludge injection pipe 1, and the main pipe 21 and the first cooling air duct 3 are arranged in sequence along the airflow direction. A compressed gas channel 2b is formed between the main pipe 21 and the sludge injection pipe 1. The main pipe 21 includes an inlet and an outlet connected through the compressed gas channel 2b. The inlet is used to connect to an external air source. One end of each branch pipe 22 is connected to the outlet, and the other end passes through the first fluid channel 3b to connect to the nozzle 5.

[0041] Specifically, the outlets of the main pipe 21 are evenly spaced in the circumferential direction, and the outlets of the branch pipes 22 , the main pipe 21 and the nozzles 5 correspond one to one.

[0042] In the above embodiments, the maximum end diameter d of the guide cone 8 is 0.35 to 0.5 times the pipe diameter D at the corresponding position of the outlet pipe section of the sludge injection pipe 1.

[0043] In the above embodiments, a compressed air inlet pipe 2a is necessarily included, and the compressed air source is connected to the inlet of the main pipe 21 through the compressed air inlet pipe 2a. Similarly, a first fluid inlet pipe 3a is necessarily included, and the first cooling air source can be connected to the first fluid channel 3b through the first fluid inlet pipe 3a. Similarly, a second fluid inlet pipe 4a is necessarily included, and the second cooling air source can be connected to the second fluid channel 4b through the second fluid inlet pipe 4a.

[0044] The first cooling air source and the second cooling air source can be the same air source, or can be independent air sources. For example, the first cooling air source and the second cooling air source can come from the secondary air of the boiler.

[0045] Furthermore, the compressed air inlet pipe 2a, the first fluid inlet pipe 3a and the second fluid inlet pipe 4a may be respectively provided with a first regulating valve 11, a second regulating valve 12 and a third regulating valve 13, which are respectively used to adjust the flow rates on the corresponding pipelines.

[0046] That is, the above device may further include a first regulating valve 11, a second regulating valve 12 and a third regulating valve 13, which are used to regulate the gas flow entering the compressed air pipe 2, the first fluid channel 3b and the second fluid channel 4b respectively.

[0047] In this way, the air volume can be adjusted according to the injection amount and moisture content of the sludge, that is, the outlet flow field of the sludge spray gun can be adjusted, so that the sludge is mixed with the compressed air and the high-temperature furnace smoke in the furnace in time, which increases the adaptability and adjustment range of the sludge spray gun.

[0048] In the above embodiments, a cleaning component 9 may be further provided. When the sludge conveying stops, a cleaning liquid is introduced to clean the sludge in the sludge injection pipe 1 to the furnace in time to prevent the sludge remaining in the sludge injection pipe 1 from drying and agglomerating when the sludge spray gun is stopped, thereby blocking the sludge injection pipe 1.

[0049] In the above embodiments, a sludge stop valve 10 may also be provided on the sludge injection pipe 1 .

[0050] The above is a detailed introduction to a sludge injection device and a sludge injection gun provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A sludge injection device, characterized in that: The invention comprises a sludge injection pipe (1), a compressed air pipe (2) and a guide cone (8), wherein the guide cone (8) is installed at the outlet pipe section of the sludge injection pipe (1), and the closer to the pipe mouth, the smaller the distance between the guide cone (8) and the corresponding sludge injection pipe (1); the outlet pipe section is also provided with at least three nozzles (5) connected to the compressed air pipe (2), and the air flow outlet direction of the nozzle (5) has an angle with the radial direction that can at least form a rotating air flow at the outlet of the outlet pipe section; the nozzles (5) are evenly arranged along the circumference, and the air flow outlet direction of the nozzle (5) has an angle with the radial direction of the sludge injection pipe (1) in the range of 35° to 65°; and the invention also comprises a first cooling air pipe (3), wherein the first cooling air pipe (3) is sleeved on the outside of the sludge injection pipe (1), and a first fluid channel (3b) is formed between the first cooling air pipe (3) and the sludge injection pipe (1). The outlet end of the first fluid channel (3b) close to the sludge injection pipe (1) is an open structure, and the other end is a closed structure, the outlet end of the sludge injection pipe (1) is completely located inside the first cooling air duct (3) or the outlet end of the sludge injection pipe (1) is flush with the open end of the first cooling air duct (3); and further comprises a second cooling air duct (4), the second cooling air duct (4) being at least sleeved outside a portion of the first cooling air duct (3), and a second fluid channel (4b) being formed between the second cooling air duct (4) and the first cooling air duct (3), the outlet end of the second fluid channel (4b) close to the sludge injection pipe (1) is an open structure, and the other end is a closed structure, the outlet end of the first cooling air duct (3) is completely located inside the second cooling air duct (4) or the open end of the first cooling air duct (3) is flush with the outlet end of the sludge injection pipe (1).

2. The sludge injection device according to claim 1, characterized in that: It also includes guide blades (6) installed on the second fluid channel (4b) and used to form a swirling airflow at the outlet end of the second fluid channel (4b), and the guide blades (6) are evenly arranged along the circumferential direction, and the swirling direction of each guide blade (6) is consistent with the swirling direction of the nozzle (5) to form an airflow with the same swirling direction.

3. The sludge injection device according to claim 2, characterized in that: It also comprises a conical expansion pipe (7), the conical expansion pipe (7) being connected to the outlet end of the second cooling air duct (4), the diameter of the conical expansion pipe (7) gradually increasing along the airflow direction, wherein the expansion angle range of the conical expansion pipe (7) is 15° to 30°, and the length is 0.6 to 0.75 times the diameter of the sludge injection pipe (1).

4. The sludge injection device according to claim 1, characterized in that: The compressed air pipe (2) comprises a main pipe (21) and a plurality of branch pipes (22); the main pipe (21) is sleeved on the outside of a portion of the sludge injection pipe (1), and the main pipe (21) and the first cooling air pipe (3) are arranged in sequence along the airflow direction; a compressed air channel is formed between the main pipe (21) and the sludge injection pipe (1); the main pipe (21) comprises an inlet and an outlet connected through the compressed air channel; the inlet is used to connect to an external air source; one end of each branch pipe (22) is connected to the outlet, and the other end passes through the first fluid channel (3b) to connect to the nozzle (5).

5. The sludge injection device according to claim 4, characterized in that: The outlets of the main pipe (21) are evenly spaced in the circumferential direction, and the branch pipes (22), the outlets of the main pipe (21) and the nozzles (5) correspond one to one.

6. The sludge injection device according to claim 1, characterized in that: It also comprises a first regulating valve (11), a second regulating valve (12) and a third regulating valve (13), which are used to regulate the gas flow entering the compressed air pipe (2), the first fluid channel (3b) and the second fluid channel (4b), respectively.

7. The sludge injection device according to any one of claims 1 to 6, characterized in that: The maximum end diameter of the guide cone (8) is 0.35 to 0.5 times the diameter of the pipe at the corresponding position of the outlet pipe section.

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