Return water distributor for boiler

Abstract

A return water distributor for a boiler is installed inside the boiler to allow the return water to absorb the waste heat of the flue gas in the furnace and reduce the temperature of the tail smoke. It includes a return water pipe and a flue gas pipe of the boiler. An inner pipe is installed in the boiler. The upper pipe opening of the inner pipe is socketed with the lower pipe opening of the flue gas pipe. The inner pipe is sleeved with an outer pipe, and a water jacket is provided between the inner and outer pipes. The upper pipe opening of the outer pipe is sealed with the upper pipe opening of the inner pipe, and the lower pipe opening of the outer pipe is sealed with the lower pipe opening of the inner pipe. The inner pipe has a plurality of first water mist spray holes densely distributed along the upper edge of the pipe wall, and the outer pipe has a plurality of transverse pipes evenly distributed along the periphery. One end of each transverse pipe is connected to the water jacket, and the pipe wall in the middle and lower part of each transverse pipe is provided with densely distributed second water mist spray holes. The water outlet of the return water pipe is connected to the water jacket. The distributor is used to perform gas-liquid heat exchange in the boiler, and has high heat exchange efficiency and long service life.

Description

Technical Field

[0001] The invention relates to a boiler device, in particular to a boiler return water distributor. Background Art

[0002] At present, most of the traditional heating equipment uses iron pipe heating technology, and the gas-liquid heat exchange scheme of water-fire fusion is in its infancy. Most of its technical means adopt S-shaped leaky plates for water sprinkling. Water flows downward along the water holes distributed on the leaky plates to form a curtain-like water sprinkling area. Since the water falls by its own weight, although the water sprinkling area can cover most of the furnace area, the gap between the water flows inside the water sprinkling area is large, and the flue gas can climb along the gap all the way to the flue gas pipe for discharge. The efficiency of gas-liquid heat exchange is low. In addition, after the open leaky plate has been used for a period of time, the impurities in the flue gas will block some of the water holes, resulting in uneven spraying and reduced efficiency. It is also easy to cause local overheating and deformation and corrosion of the fire barrel. Therefore, the existing leaky plate type water-fire gas-liquid heat exchange technology has a short service life and frequent maintenance. The residual temperature of the tail smoke discharged from the flue gas pipe of the existing boiler using the leaky plate type gas-liquid heat exchange device is high, and auxiliary equipment needs to be added for secondary cooling and residual temperature recovery, which increases the use cost and boiler floor space. Summary of the invention

[0003] The object of the present invention is to provide a return water distributor for a boiler, which can replace a leaky plate spraying device for gas-liquid heat exchange and has high heat exchange efficiency and long service life.

[0004] The technical solution of the present invention is: a return water distributor for a boiler, including a return water pipe and a flue gas pipe of the boiler, characterized in that: an inner pipe is installed in the boiler, the upper pipe mouth of the inner pipe is sleeved with the lower pipe mouth of the flue gas pipe, the inner pipe is sleeved with the outer pipe, a water jacket is provided between the inner and outer pipes, the upper pipe mouth of the outer pipe is sealedly connected to the upper pipe mouth of the inner pipe, the lower pipe mouth of the outer pipe is sealedly connected to the lower pipe mouth of the inner pipe, the inner pipe has a plurality of first water mist spray holes densely distributed along the pipe wall, the outer pipe has a plurality of transverse pipes evenly distributed along the periphery, one end of each transverse pipe is connected to the water jacket, the pipe wall in the middle and lower part of each transverse pipe is provided with densely distributed second water mist spray holes, and the water outlet of the return water pipe is connected to the water jacket.

[0005] A smoke-passing gap is arranged between the upper pipe opening of the inner pipe and the lower pipe opening of the smoke pipe.

[0006] A gap is provided between the tube wall at the outer end of each transverse tube and the inner wall of the boiler.

[0007] The first water mist spray holes are arranged in a ring array along the tube wall of the inner tube to form a water spray ring belt. There are multiple water spray ring belts, and isolation belts are arranged between adjacent water spray ring belts.

[0008] The outer periphery of each transverse tube is sheathed with an annular tube, the outer end of each transverse tube is connected with the annular tube, and the tube wall of the lower part of the annular tube is provided with densely distributed third water mist spray holes.

[0009] The annular pipe is provided with a first water return manifold, the water outlet end of the first water return manifold is communicated with the annular pipe, and the water inlet end of the first water return manifold is communicated with the water return pipe.

[0010] The outer ends of the plurality of transverse tubes are connected through a bridge tube, and a tube wall at a middle and lower part of the bridge tube is provided with densely distributed third water mist spray holes.

[0011] The bridge pipe is provided with a second water return manifold, the water outlet end of the second water return manifold is connected with the bridge pipe, and the water inlet end of the second water return manifold is connected with the water return pipe.

[0012] A connecting pipe is provided between two adjacent or spaced transverse pipes, the two ends of the connecting pipe are communicated with the insides of the corresponding two transverse pipes, and a densely distributed fourth water mist spray holes is provided on the pipe wall of the middle and lower part of the connecting pipe.

[0013] The connecting pipe is provided with a third water return manifold, the water outlet end of the third water return manifold is communicated with the connecting pipe, and the water inlet end of the third water return manifold is communicated with the water return pipe.

[0014] The working principle of the present invention is as follows: the pressurized water in the return pipe enters the water jacket layer and is sprayed out from the first water mist spray hole and the second water mist spray hole. The water is sprayed out from the water mist spray hole at a high speed to form a high-pressure water mist with a certain splashing stroke. After the water mist is sprayed out, it is dispersed in an umbrella shape by the spraying inertia. Its surface area is large, and the fine mist droplets are closely arranged with each other and have a certain air retention ability. It can almost completely and continuously capture the hot air in the furnace within its splashing range. The first water mist spray hole sprays water mist in the space of the inner tube, and the second spray pipe sprays water mist on the outer periphery of the outer tube. Water mist is sprayed downward in the boiler space, and the water mist sprayed downward by the second spray pipe can cover the entire space inside the boiler and form a downward covering pressure. While exchanging heat, it can also force the hot air in the furnace to gather in the inner tube. The water mist in the inner tube performs more intensive vertical water mist spraying on the tube wall of the inner tube, and the heat energy in the hot air is completely exchanged; the water mist after absorbing heat finally falls into the water storage area at the lower part of the boiler. The water in the water storage area is heated to the specified temperature and then sent to the heat exchanger for heat exchange or to the heat-using equipment for use through the drain pipe.

[0015] The advantages of the present invention are: in summary, the distributor can replace the leaky plate spray device to carry out gas-liquid heat exchange in the boiler, and its heat exchange efficiency is high. Since the water jacket is a closed structure and the water mist spray holes are pressure spray holes, the water mist spray holes will not be blocked by impurities in the flue gas, and the pressure return water in the water jacket and each cross pipe can continuously cool down the inner and outer pipes and the cross pipes, and will not cause technical problems such as local overheating and deformation. Therefore, the service life of the equipment is long.

[0016] The annular tube can spray water mist on the gap between the outer end of each transverse tube and the inner wall of the boiler, increase the coverage area of ​​the water mist, and fully cover the space inside the boiler with water mist, further improving the heat exchange efficiency. The bridging tube and the connecting tube are arranged between the transverse tubes with a large spacing, which can increase the spray density of the water mist and improve the heat exchange efficiency of the equipment. The multiple annular water belts separated by the isolation belt can form multiple overlapping water mist layers, so that the probability of collision with the flue gas is high, which can increase the number of gas-liquid heat exchanges, and can also suppress the flue gas to improve the heat exchange efficiency. The smoke gap can balance the gas pressure in the furnace, so that the sprayed water mist can be dispersed better. The set gap can maximize the distance of the far end of the extended transverse tube, so that the coverage spraying effect is better. Each return water manifold can introduce the return water in the return water pipe into the end of the corresponding pipe, so that the pressure of the water mist sprayed by the distributor of this application is equal. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a return water distributor for a boiler according to the present invention.

[0018] Figure 2 It is a schematic diagram of the connection structure of the inner and outer tubes and the transverse tube of the present invention.

[0019] Figure 3 yes Figure 2 Schematic diagram of the outer structure

[0020] Figure 4 It is a schematic diagram of the structure of a boiler return water distributor having a rounded rectangular annular tube.

[0021] Figure 5 It is a schematic diagram of the structure of a boiler return water distributor provided with a perfect circular annular pipe.

[0022] Figure 6 It is a schematic diagram of the structure of a return water distributor for a boiler provided with a bridge pipe and a connecting pipe.

[0023] In the figure, 1 is a return pipe, 2 is a boiler, 3 is a flue gas pipe, 4 is a smoke gap, 5 is an inner pipe, 6 is a water jacket, 7 is a first water mist spray hole, 8 is an outer pipe, 9 is a transverse pipe, 10 is a gap, 11 is a second water mist spray hole, 12 is a water spray annular belt, 13 is a heating body, 14 is a circulating pump, 15 is a heat exchanger, 16 is an upper ring plate, 17 is a lower ring plate, 18 is an annular pipe, 19 is a third water mist spray hole, 20 is a first return water manifold, 21 is a bridge pipe, 22 is a third water mist spray hole, 23 is a connecting pipe, 24 is a fourth water mist spray hole, 25 is a third return water manifold, and 26 is a second return water manifold. DETAILED DESCRIPTION

[0024] The boiler return water distributor comprises a return water pipe 1 and a flue gas pipe 3 of a boiler 2, such as Figures 1 to 3As shown, an inner tube 5 is installed in the boiler, the upper tube opening of the inner tube is sleeved with the lower tube opening of the flue gas pipe, the inner tube is sleeved with an outer tube 8, a water jacket 6 is provided between the inner and outer tubes, the upper tube opening of the outer tube is sealedly connected to the upper tube opening of the inner tube, the lower tube opening of the outer tube is sealedly connected to the lower tube opening of the inner tube, a plurality of first water mist spray holes 7 are densely arranged around the upper edge of the tube wall of the inner tube, a plurality of transverse tubes 9 are evenly arranged around the outer tube, one end of each transverse tube is connected to the water jacket, a densely arranged second water mist spray holes 11 are provided on the tube wall in the middle and lower part of each transverse tube, and a water outlet of the return water pipe is connected to the water jacket.

[0025] A smoke-passing gap 4 is provided between the upper pipe opening of the inner pipe and the lower pipe opening of the smoke pipe.

[0026] A gap 10 is provided between the tube wall at the outer end of each transverse tube and the inner wall of the boiler.

[0027] The first water mist spray holes are arranged in a circular array along the tube wall of the inner tube to form a water spray ring belt 12. There are multiple water spray ring belts, and isolation belts are provided between adjacent water spray ring belts.

[0028] like Figure 4 and Figure 5 As shown, an annular tube 18 is sleeved on the periphery of each transverse tube, and the outer end of each transverse tube is connected to the annular tube. The tube wall of the lower part of the annular tube is provided with densely distributed third water mist spray holes 19.

[0029] The annular pipe is provided with a first water return manifold 20, the water outlet end of the first water return manifold is connected to the annular pipe, and the water inlet end of the first water return manifold is connected to the water return pipe.

[0030] like Figure 6 As shown, the outer ends of the plurality of transverse tubes are connected via a bridge tube 21, and a densely distributed third water mist spray holes 22 are provided on the tube wall of the lower middle portion of the bridge tube.

[0031] The bridge pipe is provided with a second water return manifold 26, the water outlet end of the second water return manifold is connected to the bridge pipe, and the water inlet end of the second water return manifold is connected to the water return pipe.

[0032] A connecting pipe 23 is provided between two adjacent or spaced transverse pipes, and both ends of the connecting pipe are connected to the interiors of the two corresponding transverse pipes. Densely distributed fourth water mist spray holes 24 are provided on the pipe wall of the middle and lower part of the connecting pipe.

[0033] The connecting pipe is provided with a third water return manifold 25, the water outlet end of the third water return manifold is connected to the connecting pipe, and the water inlet end of the third water return manifold is connected to the water return pipe.

[0034] Each of the pipes is made of iron pipe, steel pipe or white steel pipe, and can also be rolled with iron plate, steel plate or white steel plate. In the present application, the flow rate of the return pipe should be greater than the flow rate of all water mist spray holes, that is, the flow rate of the circulating pump 14 should be greater than the sum of the flow rates of all water mist spray holes, so that the return water forms pressurized water, and each water mist spray hole can spray water mist evenly. The present application is suitable for installation at the entrance of the flue gas pipe of hot water boilers such as fuel oil, gas, alcohol-based fuel, and biomass fuel, and can quickly recover the hot air in the furnace and the tail smoke, and finally converge to the boiler water in the water storage area of ​​the boiler. The heated body 13 continues to be heated to the specified temperature and then is sent to the heat exchanger 15 through the drain pipe for heat exchange or sent to the heat-using equipment for use. Experiments have shown that through the above structure, the flue gas temperature can be lower than the return water temperature.

[0035] The annular tube has a surrounding shape that is determined by the contour of the inner wall of the boiler; Figure 4 As shown, the boiler is a rounded rectangle, and the surrounding shape of the annular tube is also a rounded rectangle; Figure 5 As shown, the boiler is a perfect circle, and the surrounding shape of the annular tube is also a perfect circle.

[0036] A pressure regulating valve is installed on the return pipe to control the uniformity of the spray. Specifically, a valve is installed on the return pipe between the return manifold and the outer pipe. By adjusting the opening of the valve, the flow rate of the return water entering the water jacket can be increased or decreased, and the flow rate of the return water entering each return manifold can be increased or decreased.

[0037] The sealed connection of the pipe orifices of the inner and outer tubes is specifically as follows: the upper pipe orifice of the outer tube is sealed and connected to the upper pipe orifice of the inner tube through the upper ring piece 16, that is, the outer ring edge of the upper ring piece is sealed and welded together with the upper pipe orifice of the outer tube, and the inner ring edge of the upper ring piece is sealed and welded together with the upper pipe orifice of the inner tube; the lower pipe orifice of the outer tube is sealed and connected to the lower pipe orifice of the inner tube through the lower ring piece 17, that is, the outer ring edge of the lower ring piece is sealed and welded together with the lower pipe orifice of the outer tube, and the inner ring edge of the lower ring piece is sealed and welded together with the lower pipe orifice of the inner tube.

[0038] The water mist spraying route of the present application is: start the circulation pump, the return water enters the water jacket and the cross pipe through the return pipe and is sprayed out from the first and second water mist spray holes. Since the flow rate of each water mist spray hole is lower than the water intake of the return water, pressurized water is formed, so that the water sprayed from the first and second water mist spray holes is in the form of mist, and the water mist is spread throughout the entire boiler. The best technical effect can make the flue gas temperature lower than the return water temperature. Compared with the prior art, the design structure of the present application is simple, compact and reasonable, the spray efficiency is high, the tail smoke temperature is effectively reduced, fuel can be saved, and its thermal efficiency is also improved to a certain extent. The discharged flue gas meets the current national environmental protection emission standards, is safe and reliable to use, has strong applicability, is simple to install, and is easy to install. It is a necessary facility in the boiler.

Claims

1. A return water distributor for a boiler, comprising a return water pipe (1) and a flue gas pipe (3) of a boiler (2), characterized in that: The boiler is provided with an inner tube (5), the upper tube opening of the inner tube is sleeved with the lower tube opening of the flue gas pipe, the inner tube is sleeved with an outer tube (8), a water jacket (6) is provided between the inner and outer tubes, the upper tube opening of the outer tube is sealedly connected with the upper tube opening of the inner tube, the lower tube opening of the outer tube is sealedly connected with the lower tube opening of the inner tube, the inner tube has a plurality of first water mist spray holes (7) densely distributed along the tube wall, the outer tube has a plurality of transverse tubes (9) evenly distributed along the tube wall, one end of each transverse tube is connected with the water jacket, the tube wall of the middle and lower part of each transverse tube is provided with densely distributed second water mist spray holes (11), and the water outlet of the return water pipe is connected with the water jacket.

2. The return water distributor for a boiler according to claim 1, characterized in that: A smoke-passing gap (4) is provided between the upper pipe opening of the inner pipe and the lower pipe opening of the smoke pipe.

3. The boiler return water distributor according to claim 1, characterized in that: A gap (10) is provided between the tube wall at the outer end of each transverse tube and the inner wall of the boiler.

4. The boiler return water distributor according to claim 1, characterized in that: The first water mist spray holes are arranged in a ring array along the wall of the inner tube to form a water spray ring belt (12), and there are a plurality of water spray ring belts, with isolation belts provided between adjacent water spray ring belts.

5. The boiler return water distributor according to claim 1, characterized in that: An annular tube (18) is sleeved on the periphery of each transverse tube, and the outer end of each transverse tube is connected to the annular tube. A densely distributed third water mist spray holes (19) are provided on the tube wall at the middle and lower part of the annular tube.

6. The return water distributor for a boiler according to claim 5, characterized in that: The annular pipe is provided with a first water return manifold (20), the water outlet end of the first water return manifold is connected to the annular pipe, and the water inlet end of the first water return manifold is connected to the water return pipe.

7. The boiler return water distributor according to claim 1, characterized in that: The outer ends of the plurality of transverse tubes are connected via a bridge tube (21), and a densely distributed third water mist spray holes (19) are provided on the tube wall at the middle and lower part of the bridge tube.

8. The boiler return water distributor according to claim 7, characterized in that: A second water return manifold (26) is provided on the bridge pipe, the water outlet end of the second water return manifold is connected to the bridge pipe, and the water inlet end of the second water return manifold is connected to the water return pipe.

9. The boiler return water distributor according to claim 1, characterized in that: A connecting pipe (23) is provided between two adjacent or spaced transverse pipes, the two ends of the connecting pipe being in communication with the interiors of the two corresponding transverse pipes, and a densely distributed fourth water mist spray holes (24) are provided on the pipe wall at the middle and lower part of the connecting pipe.

10. The boiler return water distributor according to claim 9, characterized in that: The connecting pipe is provided with a third water return manifold (25), the water outlet end of the third water return manifold is connected to the connecting pipe, and the water inlet end of the third water return manifold is connected to the water return pipe.

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