Flat plate type feed water heater device of high-capacity boiler

Abstract

The utility model discloses a flat plate type feed water heater device of a high-capacity boiler, and belongs to the technical field of boilers. The flat plate type feed water heater device of the large-capacity boiler comprises a first connecting pipe, a first collecting box, a heat exchange pipe, a second collecting box and a second connecting pipe which are sequentially connected and longitudinally arranged in a steam space between a boiler barrel cyclone separator and a top corrugated plate. The first connecting pipe is further used for connecting a water supply system, and the second connecting pipe is further used for connecting an economizer system. According to the flat plate type feed water heater device of the high-capacity boiler, the feed water temperature of the economizer is adjusted through the flat plate type feed water heater arranged in the steam space of the boiler barrel, so that the flue gas temperature of an outlet of the boiler is adjusted and kept above the lowest temperature when the boiler is in low load or changes in working conditions. On one hand, the heater guarantees a good heat transfer effect, on the other hand, corrosion of boiler water can be prevented, the service life of the heater is prolonged, and economic benefits of boiler operation are improved.

Description

Technical Field

[0001] This application belongs to the technical field of boilers, and particularly relates to a flat feed water heater device for large-capacity boilers. Background Art

[0002] At present, with the continuous improvement of people's living standards, the calorific value of corresponding domestic waste has also increased, and large-capacity and high-parameter waste incineration waste heat boilers have become a trend. During the operation of waste incineration waste heat boilers, the corrosion of the heating surface is one of the main problems, which often affects the long-term stable operation of the boiler and brings direct economic losses to the power plant. For example, if the flue gas temperature is too low, low-temperature corrosion will occur in the economizer; on the other hand, considering the subsequent flue gas treatment system of the boiler, the temperature needs to be controlled within a certain range to meet the requirements of flue gas deacidification treatment. Therefore, controlling the boiler flue gas temperature is an urgent problem to be solved, especially when the waste calorific value is unstable or the boiler is operating at low load, the flue gas temperature is likely to be too low. By using a feed water heater device in the drum, the flue gas temperature can be effectively adjusted to avoid the corrosion of the heating surface and ensure the stable operation of the boiler.

[0003] The previously used coiled tube type boiler feed water heater, due to its structural limitations, can only be arranged at both ends of the drum, with a small heat transfer area, and is generally used in small-capacity boilers. For large-capacity and high-parameter waste incineration waste heat boilers, the structural span is large, the heating surface is numerous and unevenly heated, and it is difficult to control the flue gas temperature. The coiled tube type feed water heater has a small heat transfer area, and its effect on large-capacity and high-parameter boilers is minimal and cannot play a role in adjusting the feed water temperature of the economizer. Utility Model Content

[0004] In order to solve the above technical problems, this application provides a flat feed water heater device for large-capacity boilers. The flat feed water heater device is arranged in the steam space between the cyclone separator and the top corrugated plate separator in the drum and is longitudinally arranged along the length direction of the drum, making full use of the space between the cyclone separator and the top corrugated plate separator. The heat transfer area of the flat feed water heater is proportional to the straight section length of the drum, effectively increasing the heat transfer area, and can effectively adjust the feed water temperature of the economizer, thereby achieving the purpose of adjusting the flue gas temperature.

[0005] To achieve the above application purpose, the technical solution adopted in this application is as follows:

[0006] The embodiment of this application provides a flat feed water heater device for large-capacity boilers, including: a first connecting pipe, a first header, heat exchange tubes, a second header, and a second connecting pipe that are sequentially connected and longitudinally arranged in the steam space between the drum cyclone separator and the top corrugated plate;

[0007] The first connecting pipe is also used to connect to the feed water system, and the second connecting pipe is also used to connect to the economizer system.

[0008] Optionally, the length direction of the heat exchange tube is arranged parallel to the length direction of the drum, so that the heat receiving area is proportional to the length of the drum.

[0009] Optionally, the flat feed water heater device for large-capacity boilers further includes:

[0010] A fixing assembly, which is used to fix the first connecting pipe, the first header, the heat exchange tube, the second header and the second connecting pipe in the steam space, and the heating surface is arranged in the steam space.

[0011] Optionally, the fixing assembly includes: a pipe clamp for fixing the heat exchange tube and a fixing steel plate connecting the pipe clamps.

[0012] Optionally, the flat feed water heater device for large-capacity boilers further includes:

[0013] A regulating valve, which is used to regulate the feed water flow rate of the first connecting pipe.

[0014] Compared with the prior art, the beneficial effects of the embodiments of the present application are:

[0015] The flat feed water heater device for large-capacity boilers provided by the embodiments of the present application has a straight-tube form for the heat exchange tube. Compared with the coil-type feed water heater, its structure is simpler, more convenient to manufacture, and reduces the manufacturing cost. In this way, it is convenient to be longitudinally arranged in the steam space between the cyclone separator of the drum and the top corrugated plate. The heat exchange area is proportional to the length of the drum, meeting the regulation requirements of the economizer feed water temperature for large-capacity boilers, effectively regulating the flue gas temperature, avoiding the corrosion of the heating surface, saving fuel, improving the thermal efficiency of the boiler, and ensuring the safe and stable operation of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 Shows a schematic structural diagram of a flat feed water heater device for a large-capacity boiler provided by an embodiment of the present application;

[0018] Figure 2 Shows Figure 1 The A-A cross-sectional view in

[0019] Illustration:

[0020] 1. First connecting pipe; 2. First header; 3. Heat exchange tube; 4. Pipe clamp; 5. Fixed steel plate; 6. Second header; 7. Second connecting pipe. Detailed implementation manners

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0023] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0024] In order to illustrate the technical solutions described in the present application, the following will be described by means of specific embodiments.

[0025] Please refer to Figure 1 and Figure 2 As shown, a flat feedwater heater device for a large-capacity boiler provided by an embodiment of the present application includes: a first connecting pipe 1, a first header 2, a heat exchange tube 3, a second header 6, and a second connecting pipe 7 that are sequentially connected and longitudinally arranged in the steam space between the boiler drum cyclone separator and the top corrugated plate. The first connecting pipe 1 is also used to connect to the feedwater system, and the second connecting pipe 7 is also used to connect to the economizer system.

[0026] Therefore, the feedwater enters the first header 2 in the boiler drum through the first connecting pipe 1, is heated by the heating surface of the heat exchange tube 3, is collected in the second header 6 at the other end, and then returns to the feedwater mixing header through the second connecting pipe 7 at this end and enters the economizer system. In this way, the feedwater temperature of the economizer can be effectively adjusted, so as to achieve the purpose of adjusting the flue gas temperature.

[0027] The above-mentioned large-capacity boiler flat-plate feedwater heater device has straight heat exchange tubes 3. Compared with the coil-type feedwater heater, its structure is simpler, more convenient to manufacture, and reduces the manufacturing cost. It is thus convenient to be longitudinally arranged in the steam space between the drum cyclone separator and the top corrugated plate. The heat exchange area is proportional to the length of the drum, meeting the regulation requirements of the economizer feedwater temperature for large-capacity boilers, effectively regulating the flue gas temperature, avoiding the corrosion of the heating surface, saving fuel, improving the thermal efficiency of the boiler, and ensuring the safe and stable operation of the boiler.

[0028] In some embodiments of the present application, the length direction of the heat exchange tube 3 is arranged parallel to the length direction of the drum, such that the heating area is proportional to the length of the drum. In other words, when the size of the drum increases (or decreases), the size of the heat exchange tube 3 can be correspondingly increased (or decreased), so that the heating area changes with the size of the drum, always meeting the regulation requirements of the boiler for the economizer feedwater temperature and effectively regulating the flue gas temperature.

[0029] In some embodiments of the present application, the large-capacity boiler flat-plate feedwater heater device further includes: a fixing assembly for fixing the first connecting pipe 1, the first header 2, the heat exchange tube 3, the second header 6, and the second connecting pipe 7 in the steam space, and the heating surface is arranged in the steam space. As an example, the fixing assembly includes: a pipe clamp 4 for fixing the heat exchange tube 3 and a fixing steel plate 5 connecting the pipe clamp 4.

[0030] For example, the heat exchange tube 3 is fixed in the steam space between the drum cyclone separator and the top corrugated plate separator through the pipe clamp 4 and the fixing steel plate 5, and the heating surface is arranged in the steam space. On the one hand, it can absorb the heat of the steam, and on the other hand, it can avoid the corrosion of the boiler water. The heater is longitudinally arranged, and the heating area is proportional to the length of the drum, meeting the requirements of large-capacity boilers for regulating the economizer feedwater temperature. When the boiler operating conditions change and during low-load operation, it can avoid the corrosion of the heating surface and meet the requirements of the flue gas temperature.

[0031] In some embodiments of the present application, the large-capacity boiler flat-plate feedwater heater device further includes: a regulating valve for regulating the feedwater flow rate of the first connecting pipe 1. In this way, the feedwater temperature of the economizer can be flexibly adjusted by regulating the feedwater flow rate, so as to achieve the purpose of adjusting the flue gas temperature.

[0032] In summary, for the large-capacity boiler flat-plate feedwater heater device provided by the embodiments of the present application, the feedwater with a lower temperature enters the feedwater heater of the drum, absorbs the heat of the steam, and then is sent to the economizer to adjust the feedwater temperature of the economizer, causing a change in the heat of the economizer system. In this way, the flue gas temperature at the boiler outlet can be regulated and maintained above the lowest temperature. On the one hand, this heater ensures good heat transfer effect, and on the other hand, it can prevent the corrosion of the boiler water, prolong the service life of the heater, and improve the economic benefits of boiler operation.

[0033] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A large-capacity boiler flat-plate feedwater heater device, characterized in that: include: A first connecting pipe, a first header, a heat exchange pipe, a second header and a second connecting pipe are sequentially connected and longitudinally arranged in the steam space between the drum cyclone separator and the top corrugated plate; The first connecting pipe is also used to connect to a water supply system, and the second connecting pipe is also used to connect to an economizer system.

2. The large-capacity boiler flat-plate feedwater heater device according to claim 1 is characterized in that: The length direction of the heat exchange tube is arranged parallel to the length direction of the boiler drum, so that the heating area is proportional to the length of the boiler drum.

3. The large-capacity boiler flat-plate feedwater heater device according to claim 1 is characterized in that: Also includes: A fixing assembly is used to fix the first connecting pipe, the first header, the heat exchange pipe, the second header and the second connecting pipe in the steam space, and the heating surface is arranged in the steam space.

4. The large-capacity boiler flat-plate feedwater heater device according to claim 3 is characterized in that: The fixing assembly comprises: a tube clamp for fixing the heat exchange tube and a fixing steel plate connected to the tube clamp.

5. The large-capacity boiler flat-plate feedwater heater device according to any one of claims 1 to 4, characterized in that: Also includes: A regulating valve, wherein the regulating valve is used to adjust the water supply flow of the first connecting pipe.

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