Structural device for evaporation heating surface of supercritical direct-current waste heat boiler

Abstract

The utility model discloses a structure device for an evaporation heating surface of a supercritical direct-current waste heat boiler, which comprises a heating surface arranged in a flue of the waste heat boiler, the heating surface is communicated with an inlet header and an outlet header through pipelines, the heating surface is a screen group type heating surface and comprises a screen A heating surface and a screen B heating surface, the first screen heating surface and the second screen heating surface are respectively formed by assembling and assembling mutually communicated heating pipes side by side in parallel, the heating pipes of the first screen heating surface are respectively communicated with a first screen inlet header and a first screen outlet header through pipelines, and the heating pipes of the second screen heating surface are respectively communicated with a second screen inlet header and a second screen outlet header through pipelines. According to the utility model, the screen group type heating surface is arranged in the flue of the waste heat boiler, so that the flue gas and the working medium can flow through at one time, the control requirements of the critical section of the supercritical boiler on the mass flow rate and the heat absorption capacity of the working medium are met, and the working medium can be changed into superheated steam in the outlet header from water in the inlet header.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat boilers, in particular to a structural device for the evaporation heating surface of a supercritical once-through waste heat boiler. Background Technique

[0002] Under the background of energy conservation and emission reduction, improving the power generation efficiency of power plants is the main way, and increasing the parameters of the unit is the most effective means. The parameters of thermal power generating units in China have reached the parameters of high-efficiency supercritical, reaching the international leading level. However, the steam parameters of waste heat boilers in China are still below the critical pressure. To increase the parameters of waste heat boilers, in addition to improving the system settings, it is also necessary to innovate and develop the structure of the waste heat boilers themselves.

[0003] As the pressure on the working medium side of the boiler continues to increase and reaches and exceeds the critical pressure, the working medium has no latent heat of vaporization, and there is no fixed demarcation line (i.e., saturation temperature) during the process of water turning into steam. Therefore, the evaporation of the boiler no longer requires a circulating evaporation structural device (composed of elements such as a steam drum, downcomer, and water wall), but requires a structural device that can pass through once and reach a certain degree of superheat, and this device also needs to have a certain high mass flow rate and a relatively long residence time in the furnace. Content of the Utility Model

[0004] To solve the above technical problems, the utility model designs a structural device for the evaporation heating surface of a supercritical once-through waste heat boiler, which can be applied to the steam-water conversion process of a supercritical once-through waste heat boiler, meet the above technical requirements, and ensure the safe and stable operation of the boiler without tube explosion.

[0005] The utility model adopts the following technical scheme:

[0006] A structural device for the evaporation heating surface of a supercritical once-through waste heat boiler, including a heating surface arranged in the waste heat boiler flue. The heating surface is connected to an inlet header and an outlet header through pipelines. The heating surface is a panel-type heating surface, including a first panel heating surface and a second panel heating surface. The heating tubes of the first panel heating surface and the second panel heating surface are respectively assembled in parallel by being connected to each other and arranged side by side. The heating tubes of the first panel heating surface are respectively connected to a first panel inlet header and a first panel outlet header through pipelines, and the heating tubes of the second panel heating surface are respectively connected to a second panel inlet header and a second panel outlet header through pipelines.

[0007] Preferably, the heating tubes of the first panel heating surface and the second panel heating surface are respectively arranged at an inclined angle with respect to the first panel inlet header, the first panel outlet header, the second panel inlet header, and the second panel outlet header.

[0008] Preferably, the inclined angle is 8 - 40°.

[0009] Preferably, the heating tubes of the heating surfaces of the first screen and the second screen are respectively in the form of plain tubes or finned tubes.

[0010] Preferably, the heating surfaces of the first screen and the second screen are fixedly connected by tube screen fixing blocks.

[0011] The beneficial effects of the present utility model are as follows: The present utility model arranges a screen-type heating surface in the flue of the waste heat boiler, which has the characteristic that both the flue gas and the working medium flow through it once, meeting the control requirements of the critical section of the supercritical boiler for the mass flow rate and heat absorption of the working medium, enabling the working medium to change from water in the inlet header to superheated steam in the outlet header. Description of the Drawings

[0012] Figure 1 is a structural schematic diagram of the present utility model;

[0013] Figure 2 is Figure 1 the side view of

[0014] In the figure: 1. First screen inlet header, 2. Second screen inlet header, 3. First screen outlet header, 4. Second screen outlet header, 5. Screen-type heating surface, 6. Heating tube, 7. Tube screen fixing block, 8. Waste heat boiler flue. Detailed Embodiments

[0015] The following are specific embodiments, in combination with the drawings, to further specifically describe the technical solutions of the present utility model:

[0016] Embodiment: As shown in Figure 1 and Figure 2 , a structural device for the evaporative heating surface of a supercritical once-through waste heat boiler includes a heating surface arranged in the waste heat boiler flue 8. The heating surface is connected to the inlet header and the outlet header through pipelines. The heating surface is a screen-type heating surface 5, including a first screen heating surface and a second screen heating surface. The heating tubes of the first screen heating surface and the second screen heating surface are respectively assembled in parallel rows by being connected to each other. The heating tubes of the first screen heating surface are respectively connected to the first screen inlet header 1 and the first screen outlet header 3 through pipelines, and the heating tubes of the second screen heating surface are respectively connected to the second screen inlet header 2 and the second screen outlet header 4 through pipelines.

[0017] The heating tubes of the first screen heating surface and the second screen heating surface are respectively arranged at an inclined angle with respect to the first screen inlet header, the first screen outlet header, the second screen inlet header, and the second screen outlet header. The inclined angle is 8 - 40°.

[0018] The heating tubes of the first screen heating surface and the second screen heating surface are respectively in the form of plain tubes or finned tubes.

[0019] The first screen heating surface and the second screen heating surface are fixedly connected by tube screen fixing blocks 7. This serves to reinforce the tube screen and bear the self-weight of the tube screen.

[0020] In a supercritical once-through waste heat boiler, multiple structural devices of the present invention can be arranged through calculation according to the evaporation capacity of the main steam of the boiler, and they are arranged in parallel to meet the evaporation arrangement requirements of the working medium of the supercritical once-through waste heat boiler in the critical section.

[0021] The present invention arranges a screen-type heating surface in the waste heat boiler flue gas duct, which has the characteristic that both the flue gas and the working medium flow through once, meeting the control requirements of the working medium mass flow rate and heat absorption in the critical section of the supercritical boiler, and enabling the working medium to change from water in the inlet header to superheated steam in the outlet header.

[0022] The above-described embodiments are only a preferred solution of the present invention, and do not impose any form of limitation on the present invention. There are other variations and modifications without exceeding the technical solutions recorded in the claims.

Claims

1. A structural device for the evaporative heating surface of a supercritical once-through waste heat boiler, comprising a heating surface arranged in the waste heat boiler flue, the heating surface is connected to an inlet header and an outlet header through pipelines, and is characterized in that, The heat-absorbing surface is a panel-type heat-absorbing surface, including the first panel heat-absorbing surface and the second panel heat-absorbing surface. The first panel heat-absorbing surface and the second panel heat-absorbing surface are respectively assembled by arranging heat-absorbing tubes that are interconnected and arranged side by side in parallel. The heat-absorbing tubes of the first panel heat-absorbing surface are respectively connected to the first panel inlet header and the first panel outlet header through pipelines, and the heat-absorbing tubes of the second panel heat-absorbing surface are respectively connected to the second panel inlet header and the second panel outlet header through pipelines.

2. The structural device for the evaporative heating surface of a supercritical once-through waste heat boiler according to claim 1, characterized in that, The heat-absorbing tubes of the first panel heat-absorbing surface and the second panel heat-absorbing surface are respectively arranged at an inclined angle with respect to the first panel inlet header, the first panel outlet header, the second panel inlet header, and the second panel outlet header.

3. The structural device for the evaporative heating surface of a supercritical once-through waste heat boiler according to claim 2, characterized in that, The inclined angle is 8 - 40°.

4. The structural device for the evaporative heating surface of a supercritical once-through waste heat boiler according to claim 1, characterized in that, The heat-absorbing tubes of the first panel heat-absorbing surface and the second panel heat-absorbing surface respectively adopt the form of plain tubes or finned tubes.

5. The structural device for the evaporation heating surface of a supercritical once-through waste heat boiler according to claim 1, wherein The first panel heat-absorbing surface and the second panel heat-absorbing surface are fixedly connected through tube panel fixing blocks.

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