A boiler flue gas waste heat recovery device

Abstract

The utility model discloses a boiler flue gas waste heat recovery device, including cylinder, the cylinder below is the dust collection area, and the upper is the heat exchange area, the dust collection area is from below respectively to the first cylinder section and the reverse circular taper section, and the first cylinder section side is equipped with the flue gas air inlet pipe of tangential setting, the heat exchange area is from below respectively to the circular taper section and the second cylinder section, and the second cylinder section near the side of top is equipped with the flue gas air outlet pipe, the second cylinder section top is equipped with the water inlet pipe and the water outlet pipe, be equipped with the spiral heat exchange pipe in the heat exchange area, and the spiral heat exchange pipe is connected the water inlet pipe and the water outlet pipe respectively, the utility model discloses utilize the dust collection area to separate the particulate matter in the flue gas, reduce the particulate matter content of entering the heat exchange area, effectively reduce the particulate matter in the spiral heat exchange pipe surface adhesion, slow down the formation of heat exchange pipe surface heat insulating layer to improve the heat replacement efficiency, improve the waste heat recovery efficiency, reduce energy waste.

Description

Technical Field

[0001] This utility model relates to the field of waste heat recovery technology, and in particular to a waste heat recovery device for boiler flue gas. Background Technology

[0002] Boilers are widely used as important energy conversion devices. They convert input fuel chemical energy and electrical energy into steam, high-temperature water, or organic heat carriers with a certain amount of thermal energy to meet the energy needs of industrial processes, heating, power generation, and other applications. However, during boiler operation, the flue gas generated by fuel combustion carries a large amount of waste heat and is directly emitted, resulting in a significant waste of energy. Therefore, waste heat recovery devices have emerged to recover and utilize the waste heat from flue gas, thereby improving energy efficiency.

[0003] During the heat exchange process in a waste heat recovery device, the flue gas contains a large amount of particulate matter, which gradually adheres to the surface of the heat exchange tubes over time. As operating time increases, the thickness of the particulate impurities adhering to the surface of the heat exchange tubes continuously accumulates. This thickening of impurities on the surface of the heat exchange tubes forms an insulating layer, hindering the transfer of heat between the inside and outside of the heat exchange tubes, thus severely affecting the heat exchange efficiency and leading to a significant reduction in waste heat recovery efficiency. Utility Model Content

[0004] To address the aforementioned problems, this invention provides a boiler flue gas waste heat recovery device, which can reduce the particulate matter content in the flue gas and extend the service life of the heat exchanger.

[0005] Therefore, the technical solution of this utility model is: a boiler flue gas waste heat recovery device, including a cylinder, with an ash collection area at the bottom and a heat exchange area at the top; the ash collection area consists of a first cylindrical section and an inverted conical section from bottom to top, and the first cylindrical section has a tangentially arranged flue gas inlet pipe on its side; the heat exchange area consists of a conical section and a second cylindrical section from bottom to top, and the second cylindrical section has a flue gas outlet pipe on its side near the top; the top of the second cylindrical section has a sealing cover, and the sealing cover has an inlet pipe and an outlet pipe; the heat exchange area has a spiral heat exchange tube, which is connected to the inlet pipe and the outlet pipe respectively, and the spiral heat exchange tube extends into the conical section.

[0006] Based on the above scheme and as a preferred embodiment of the above scheme: the spiral heat exchange tube includes a downward spiraling inlet section and an upward spiraling outlet section, and the spiral diameter of the inlet section gradually decreases and the spiral diameter of the outlet section gradually increases within the conical section.

[0007] Based on the above scheme and as a preferred embodiment of the above scheme: a dust collection drawer is provided below the first cylindrical section, an opening is provided on the first cylindrical section for the dust collection drawer to enter and exit, and a sealing ring is provided between the dust collection drawer and the opening; a handle is provided on the outside of the dust collection drawer.

[0008] Based on the above scheme and as a preferred embodiment of the above scheme: several flow guide baffles are provided on the inner wall of the second cylindrical section.

[0009] Based on the above scheme and as a preferred embodiment of the above scheme: the outer circumferential wall of the spiral heat exchange tube is provided with heat dissipation fins.

[0010] When flue gas carrying particulate matter enters the first cylindrical section through the tangential flue gas inlet pipe, a rotating airflow is formed within the cylindrical section; this is the principle of cyclone separation. Under the action of centrifugal force, relatively large particles are thrown towards the cylinder wall and slide down along it. Because the upper section is an inverted cone, as the diameter of the cone gradually decreases, the radius of airflow rotation becomes smaller, and the centrifugal force increases, further enhancing the separation effect on particulate matter. This allows more particles to be separated and fall below the first cylindrical section, thus achieving the separation of particulate matter within the flue gas and reducing the particulate matter content entering the heat exchange zone.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] By using the ash collection zone to separate particulate matter in the flue gas, the particulate matter content entering the heat exchange zone is reduced, effectively reducing the adhesion of particulate matter to the surface of the spiral heat exchange tube, slowing down the formation of the insulation layer on the surface of the heat exchange tube, thereby improving the heat exchange efficiency, increasing the waste heat recovery efficiency, and reducing energy waste.

[0013] The spiral heat exchanger tube is divided into a downward-spiraling inlet section and an upward-spiraling outlet section. Within the conical section, the diameter of the inlet section gradually decreases, while the diameter of the outlet section gradually increases. This design increases the contact time and area between the water and the flue gas, resulting in more thorough heat exchange and further improving waste heat recovery efficiency. Simultaneously, heat dissipation fins can be installed on the outer circumferential wall of the spiral heat exchanger tube, increasing the heat exchange area between the tube and the flue gas, which helps to absorb heat from the flue gas more efficiently and improve waste heat recovery.

[0014] A dust collection drawer is installed at the bottom of the first cylindrical section for easy collection and cleaning of separated particles; a sealing ring is installed between the dust collection drawer and the opening to prevent dust leakage. A handle is provided on the outside for easy operation of the dust collection drawer, making cleaning work more convenient.

[0015] The inner wall of the second cylindrical section is equipped with several flow guide baffles, which can change the flow path and velocity of the flue gas in the heat exchange zone, so that the flue gas can contact the spiral heat exchange tube more evenly, thereby improving the uniformity and efficiency of heat exchange. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of Example 1;

[0017] Figure 2 This is a schematic diagram of the internal structure of Example 1;

[0018] Figure 3 This is a schematic diagram of the internal flow channel of Example 1;

[0019] Figure 4 This is a schematic diagram of the internal structure of Example 2;

[0020] Figure 5 This is a schematic diagram of the spiral heat exchange tube in Example 3.

[0021] The following are marked in the diagram: cylinder 1, first cylindrical section 11, inverted conical section 12, conical section 13, second cylindrical section 14, sealing cover 15, water inlet pipe 16, water outlet pipe 17, flue gas inlet pipe 2, ash collection drawer 3, flue gas outlet pipe 4, spiral heat exchange tube 5, water inlet section 51, water outlet section 52, heat dissipation fins 53, and flow guide baffle 6. Detailed Implementation

[0022] In the description of this utility model, it should be noted that the directional terms such as "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this utility model.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "several" or "a number" means two or more, unless otherwise explicitly specified.

[0024] Example 1

[0025] The boiler flue gas waste heat recovery device described in this embodiment includes a cylindrical body 1, with an ash collection area at the bottom and a heat exchange area at the top. The ash collection area consists of a first cylindrical section 11 and an inverted conical section 12 from bottom to top. A tangentially arranged flue gas inlet pipe 2 is provided on the side of the first cylindrical section 11. An ash collection drawer 3 is provided below the first cylindrical section 11, and an opening for the ash collection drawer 3 to enter and exit is provided on the first cylindrical section 11. A sealing ring is provided between the ash collection drawer 3 and the opening. A handle is provided on the outside of the ash collection drawer 3 to facilitate users to clean up accumulated particles and dust in a timely manner.

[0026] The heat exchange zone consists of a conical section 13 and a second cylindrical section 14 from bottom to top. A flue gas outlet pipe 4 is located on the side of the second cylindrical section 14 near the top. A sealing cap 15 is located at the top of the second cylindrical section 14, and an inlet pipe 16 and an outlet pipe 17 are mounted on the sealing cap 15. A spiral heat exchange tube 5 is installed within the heat exchange zone, connecting the inlet pipe 16 and the outlet pipe 17 respectively, with the bottom of the spiral heat exchange tube 5 extending into the conical section 13. The spiral heat exchange tube 5 includes a downward-spiraling inlet section 51 and an upward-spiraling outlet section 52. The spiral diameter of the inlet section 51 gradually decreases within the conical section 13, while the spiral diameter of the outlet section 52 gradually increases, meaning the inlet and outlet of the spiral heat exchange tube 5 are located at the same end. This design increases the contact time and area between water and flue gas, resulting in more thorough heat exchange and further improving waste heat recovery efficiency.

[0027] When using:

[0028] When flue gas carrying particulate matter enters the first cylindrical section 11 through the tangential flue gas inlet pipe 2, a rotating airflow is formed within the cylindrical section. Under the action of centrifugal force, relatively large particles are thrown towards the cylinder wall and slide down along it. The airflow rotates upwards, and as the diameter of the inverted conical section 12 gradually decreases, the radius of rotation of the airflow becomes smaller, and the centrifugal force increases, further enhancing the separation effect on particulate matter. This allows more particles to be separated and fall into the ash collection drawer 3 below the first cylindrical section 11, thereby achieving the separation of particulate matter within the flue gas and reducing the particulate matter content entering the heat exchange zone.

[0029] The inlet pipe 16 of the heat exchange zone is connected to a cold water source. The cold water flows into the conical section 13 through the downward spiraling inlet section 51, and then exits the conical section 13 through the upward spiraling outlet section 52. During the flow, the cold water comes into contact with the rotating and rising flue gas, and heat exchange is fully carried out. The heated water flows out from the outlet pipe 17. At the same time, the flue gas after heat exchange is discharged from the flue gas outlet pipe 4 on the side of the second cylindrical section.

[0030] Example 2

[0031] This embodiment has the same structure as Embodiment 1, except that: several flow guide baffles 6 are provided on the inner wall of the second cylindrical section 14. The flow guide baffles 6 can change the flow path and velocity of the flue gas in the heat exchange zone, so that the flue gas contacts the spiral heat exchange tube more evenly, thereby improving the uniformity and efficiency of heat exchange.

[0032] Example 3

[0033] This embodiment has the same structure as Embodiment 1, except that: the outer circumferential wall of the spiral heat exchange tube 5 is provided with heat dissipation fins 53. The heat dissipation fins 53 increase the heat exchange area between the heat exchange tube and the flue gas, which helps to absorb heat from the flue gas more efficiently and improve the waste heat recovery effect.

[0034] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A boiler flue gas waste heat recovery device, comprising a cylindrical body, characterized in that: The lower part of the cylinder is the ash collection area, and the upper part is the heat exchange area. The ash collection area consists of a first cylindrical section and an inverted conical section from bottom to top. The first cylindrical section has a tangentially arranged flue gas inlet pipe on its side. The heat exchange area consists of a conical section and a second cylindrical section from bottom to top. The second cylindrical section has a flue gas outlet pipe on its side near the top. The top of the second cylindrical section is equipped with a sealing cover, which has an inlet pipe and an outlet pipe. The heat exchange area is equipped with spiral heat exchange tubes, which are connected to the inlet pipe and the outlet pipe respectively, and the spiral heat exchange tubes extend into the conical section.

2. The boiler flue gas waste heat recovery device as described in claim 1, characterized in that: The spiral heat exchange tube includes a downward spiral inlet section and an upward spiral outlet section, with the spiral diameter of the inlet section gradually decreasing and the spiral diameter of the outlet section gradually increasing within the conical section.

3. The boiler flue gas waste heat recovery device as described in claim 1, characterized in that: A dust collection drawer is provided below the first cylindrical section, and an opening is provided on the first cylindrical section for the dust collection drawer to enter and exit, and a sealing ring is provided between the dust collection drawer and the opening; a handle is provided on the outside of the dust collection drawer.

4. The boiler flue gas waste heat recovery device as described in claim 1, characterized in that: The inner wall of the second cylindrical section is provided with several flow guide baffles.

5. The boiler flue gas waste heat recovery device as described in claim 1, characterized in that: The outer circumferential wall of the spiral heat exchange tube is provided with heat dissipation fins.

Images