Waste incineration power generation flue gas waste heat recovery mechanism

Abstract

The utility model discloses a kind of waste incineration power generation flue gas waste heat recovery mechanism, including heat exchanger shell (1), heat exchanger shell (1) two ends are equipped with tube sheet (2), tube sheet (2) is equipped with head (3) outside, one head (3) is connected with liquid inlet (4), another head (3) is connected with liquid outlet (5), between two tube sheets (2) are equipped with a group of fluorine plastic steel heat exchange tube (6), every fluorine plastic steel heat exchange tube (6) is equipped with multiple section fluorine plastic steel material spiral fin (7), adjacent spiral fin (7) is intermittently distributed between;The upper end of heat exchanger shell (1) close to liquid inlet (4) is equipped with gas outlet (8), the other end below heat exchanger shell (1) is equipped with smoke inlet (9), the middle part of the upper surface of heat exchanger shell (1) is also equipped with soot blowing mechanism (10), heat exchanger shell (1) below is equipped with ash outlet (11).The utility model has the characteristics of can effectively reduce the ash deposition.

Description

Technical Field

[0001] This utility model relates to a flue gas waste heat recovery device, and more particularly to a waste incineration power generation flue gas waste heat recovery mechanism. Background Technology

[0002] Waste-to-energy incineration is a primary method for municipal solid waste treatment. During incineration, a large amount of high-temperature flue gas (typically above 200°C) is generated. Currently, the utilization of this high-temperature flue gas mainly involves using waste heat boilers to recover heat from the flue gas, generating steam to drive a steam turbine generator. However, after passing through the waste heat boiler, the exhaust gas temperature is usually still between 180-250°C. This portion of the low-temperature flue gas still contains a significant amount of sensible heat, and direct emission would result in energy waste. To better utilize this heat, waste heat recovery units are typically installed for heat recovery. However, because waste incineration flue gas contains dust, fly ash easily adheres to and accumulates on heat exchange surfaces, reducing heat exchange efficiency and even clogging the flue. Therefore, existing technologies suffer from the problem of easy ash accumulation. Summary of the Invention

[0003] The purpose of this invention is to provide a waste heat recovery mechanism for flue gas from waste incineration power generation. This invention effectively reduces ash accumulation.

[0004] The technical solution of this utility model: a waste incineration power generation flue gas waste heat recovery mechanism, including a heat exchanger shell, tube sheets at both ends of the heat exchanger shell, and end caps on the outside of the tube sheets. One end cap is connected to a liquid inlet and the other end cap is connected to a liquid outlet. A set of fluoroplastic steel heat exchange tubes is provided between the two tube sheets. Each fluoroplastic steel heat exchange tube is provided with multiple sections of fluoroplastic steel spiral fins, which are intermittently distributed between adjacent spiral fins. An air outlet is provided at one end of the heat exchanger shell near the liquid inlet, and a flue gas inlet is provided at the other end of the heat exchanger shell. A soot blowing mechanism is also provided in the middle of the upper surface of the heat exchanger shell, and an ash outlet is provided at the bottom of the heat exchanger shell.

[0005] In the aforementioned waste incineration power generation flue gas waste heat recovery mechanism, the pitch of the spiral fins is 12mm-20mm.

[0006] In the aforementioned waste incineration power generation flue gas waste heat recovery mechanism, the soot blowing mechanism includes a rotating seat located on the upper surface of the heat exchanger shell, a toothed surface fixed on the outer edge of the rotating seat, a meshing rack on the outer side of the toothed surface, and a drive cylinder connected to the rack; a shock wave soot blower is provided on the rotating seat, and soot blowing nozzles arranged at an angle downwards are provided below the rotating seat.

[0007] In the aforementioned waste incineration power generation flue gas waste heat recovery mechanism, the tilt angle of the soot blowing nozzle is 5-10 degrees.

[0008] In the aforementioned waste incineration power generation flue gas waste heat recovery mechanism, the edge of the spiral fins is also provided with a wave-shaped structure.

[0009] Compared with existing technologies, this invention uses fluoroplastic steel heat exchange tubes for heat exchange, which effectively improves the corrosion resistance and anti-sticking effect of the heat exchange tubes, and helps reduce dust adhesion and accumulation. By setting spiral fins on the surface of the fluoroplastic steel heat exchange tubes and using a segmented, spaced distribution with a large pitch of 12-20mm, a spacious channel is provided for fly ash passage, fundamentally avoiding the formation of ash bridges. At the same time, the wavy and discontinuous structure disrupts the stable laminar boundary layer of the flue gas, enhancing the flue gas turbulence, thereby improving the heat exchange effect. This application also incorporates a soot blowing mechanism in the middle of the upper surface, which, in conjunction with the spiral fins and the fluoroplastic steel heat exchanger, effectively reduces dust accumulation and improves heat exchange efficiency.

[0010] In addition, the edges of the spiral fins have a wavy structure. Dust cannot form a continuous and solid dust layer at the concave and convex parts and the discontinuous gaps. It is more likely to break and peel off under the action of sonic blowing or thermal expansion and contraction.

[0011] The soot blowing nozzles of the soot blowing mechanism adopt an inclined downward arrangement structure, and the soot blowing area of ​​the soot blowing nozzles can be rotated and adjusted by a rotating seat, so as to cover more soot blowing areas and improve the soot removal effect. Attached Figure Description

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

[0013] The labels in the attached diagram are as follows: 1-Heat exchanger shell, 2-Tube sheet, 3-End cap, 4-Liquid inlet, 5-Liquid outlet, 6-Fluoroplastic steel heat exchange tube, 7-Helical fins, 8-Air outlet, 9-Fum inlet, 10-Soot blowing mechanism, 11-Ash outlet, 101-Shock soot blower, 102-Rotating seat, 103-Soot blowing nozzle, 104-Rack, 105-Drive cylinder. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0015] Example. A waste-to-energy flue gas waste heat recovery mechanism is configured as follows: Figure 1As shown, the device includes a heat exchanger shell 1, tube sheets 2 at both ends of the heat exchanger shell 1, and end caps 3 on the outside of the tube sheets 2. One end cap 3 is connected to a liquid inlet 4, and the other end cap 3 is connected to a liquid outlet 5. A set of fluoroplastic steel heat exchange tubes 6 are provided between the two tube sheets 2. Each fluoroplastic steel heat exchange tube 6 is provided with multiple sections of fluoroplastic steel spiral fins 7, which are intermittently distributed between adjacent spiral fins 7. An air outlet 8 is provided at one end of the heat exchanger shell 1 near the liquid inlet 4, and a smoke inlet 9 is provided at the other end of the heat exchanger shell 1 below. A soot blowing mechanism 10 is also provided in the middle of the upper surface of the heat exchanger shell 1, and an ash outlet 11 is provided at the bottom of the heat exchanger shell 1.

[0016] The pitch of the spiral fin 7 is 12mm-20mm.

[0017] The soot blowing mechanism 10 includes a rotating seat 102 located on the upper surface of the heat exchanger shell 1. A toothed surface is fixed on the outer edge of the rotating seat 102, and a meshing rack 104 is provided on the outer side of the toothed surface. The rack 104 is connected to a drive cylinder 105. A shock wave soot blower 101 is provided on the rotating seat 102, and a soot blowing nozzle 103 is provided below the rotating seat 102 and arranged at an angle downward.

[0018] The tilt angle of the soot blowing nozzle 103 is 5-10 degrees.

[0019] The spiral fin 7 also has a wavy structure along its edge.

[0020] The intermittent gap provides space for the thermal expansion of the spiral fins under alternating hot and cold conditions, preventing cracking at the root of the fins due to stress concentration.

[0021] The waste heat recovery mechanism of this application is installed on the tail flue after the waste heat boiler.

[0022] The heat exchange medium inside the fluoroplastic steel heat exchange tubes is demineralized water or heat transfer oil. The recovered heat is used to heat boiler feedwater, heat combustion air, or provide heating for the plant area and surrounding buildings.

[0023] An ash hopper is located below the ash outlet.

[0024] The tube sheet has corresponding holes for installing fluoroplastic steel heat exchange tubes.

[0025] During manufacturing, spiral fins are first spirally welded to the outer wall of the base tube with a large pitch of 12mm-20mm. During the welding process, every 100mm-200mm of length is welded, the process is paused and a gap of 5mm-10mm is left to form an intermittent structure.

[0026] The working process of this utility model is as follows: the heat exchange liquid enters the end cap from the inlet, then flows into the fluoroplastic steel heat exchange tube. After heat exchange between the fluoroplastic steel heat exchange tube and the flue gas in the heat exchanger shell, it flows out to the other end cap and is finally discharged from the outlet. Meanwhile, the high-temperature flue gas flows into the heat exchanger shell from the lower inlet, then flows upward and exchanges heat with the heat exchange tube, and is finally discharged from the outlet. During this process, the flue gas is disturbed by the spiral fins, which enhances the turbulence of the flue gas.

[0027] When the soot blowing mechanism is started according to a preset program (e.g., once per shift), the generated sound waves can effectively shake off and loosen accumulated ash. The specific process is as follows: the drive cylinder controls the rack to move, which in turn drives the gear plate to rotate, causing the rotating seat to rotate, thus rotating the soot blowing nozzle. After rotating to the set position, the rack resets, causing the soot blowing nozzle to rotate back. This allows for adjustment of the soot blowing direction, expanding the soot blowing area and improving the soot blowing quality.

Claims

1. A waste-to-energy incineration flue gas waste heat recovery mechanism, characterized in that: The heat exchanger includes a heat exchanger shell (1), tube sheets (2) at both ends of the heat exchanger shell (1), and end caps (3) on the outside of the tube sheets (2). One end cap (3) is connected to a liquid inlet (4), and the other end cap (3) is connected to a liquid outlet (5). A set of fluoroplastic steel heat exchange tubes (6) is provided between the two tube sheets (2). Each fluoroplastic steel heat exchange tube (6) is provided with multiple sections of spiral fins (7) made of fluoroplastic steel. The adjacent spiral fins (7) are intermittently distributed. An air outlet (8) is provided at one end of the heat exchanger shell (1) near the liquid inlet (4), and a smoke inlet (9) is provided at the other end of the heat exchanger shell (1). A soot blowing mechanism (10) is also provided in the middle of the upper surface of the heat exchanger shell (1), and an ash outlet (11) is provided at the bottom of the heat exchanger shell (1).

2. The waste heat recovery mechanism for waste incineration power generation according to claim 1, characterized in that: The pitch of the spiral fins (7) is 12mm-20mm.

3. The waste heat recovery mechanism for waste incineration power generation according to claim 1, characterized in that: The soot blowing mechanism (10) includes a rotating seat (102) located on the upper surface of the heat exchanger shell (1). The outer edge of the rotating seat (102) is fixed with a toothed surface, and a meshing rack (104) is provided on the outer side of the toothed surface. The rack (104) is connected to a drive cylinder (105). A shock wave soot blower (101) is provided on the rotating seat (102), and a soot blowing nozzle (103) is provided below the rotating seat (102) and arranged at an angle downward.

4. The waste heat recovery mechanism for waste incineration power generation according to claim 3, characterized in that: The tilt angle of the soot blowing nozzle (103) is 5-10 degrees.

5. The waste heat recovery mechanism for waste incineration power generation according to claim 1, characterized in that: The spiral fins (7) also have a wavy structure along their edges.

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