An asymmetrically arranged rotary air preheater system

Abstract

The application discloses a kind of asymmetrically arranged rotary air preheater systems, belong to a kind of preheater field, asymmetrically arranged rotary air preheater system, including economizer, SCR reactor, bifurcated flue, connecting flue, auxiliary flue, rotary preheater described economizer bottom fixed connection described auxiliary flue one end;Described auxiliary flue other end fixed connection described rotary preheater top end.The asymmetrically arranged rotary air preheater system disclosed in the application reduces the exhaust gas temperature of the air preheater, without increasing the height of the heat exchange elements of the rotary heat exchanger, so the design resistance will not be too high, and it is also beneficial to the blowing of the soot blower, facilitating the normal operation of the boiler. The cold end heat transfer element of the rotary air preheater is covered with enamel surface, which can resist acid corrosion and effectively control low temperature corrosion.

Description

Technical Field

[0001] This invention relates to a preheater, and more particularly to an asymmetrically arranged rotary air preheater system. Background Technology

[0002] Cycle thermal efficiency and boiler efficiency are important factors affecting the economic efficiency of coal-fired power plants. Cold source loss directly affects the cycle thermal efficiency of the boiler, and boiler flue gas loss is the largest component of boiler heat loss. High boiler flue gas temperature leads to increased coal consumption in thermal power plants. Therefore, reducing the boiler flue gas temperature can significantly reduce coal consumption and save energy. Most power plant boilers are equipped with economizers, air preheaters, and other equipment in the tail flue to recover heat from the flue gas and reduce the flue gas temperature. If the coal has a high moisture content, and the boiler pulverizing system needs to dry the coal through the temperature of the primary air, boilers burning high-moisture coal have higher requirements for the outlet primary hot air temperature of the air preheater.

[0003] Conventional power plant boilers are equipped with two equal-sized, three-compartment rotary air preheaters to dry coal with high moisture content using hot air. The hot air temperature is higher than that of conventional bituminous coal, which means that the flue gas temperature entering the rotary preheater generally needs to reach a higher temperature. Therefore, the exhaust gas temperature of lignite boilers is relatively high, and the flue gas temperature at the outlet of the rotary air preheater is generally higher than that of conventional bituminous coal units. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the technical problem to be solved by the present invention is to propose an asymmetrically arranged rotary air preheater system, which reduces the exhaust gas temperature of the air preheater, does not require increasing the height of the heat exchange elements of the rotary heat exchanger, so the design resistance will not be too high, and it is also conducive to the purging of the soot blower, which facilitates the normal operation of the boiler. The cold end heat transfer elements of the rotary air preheater are covered with enamel, which can resist acid corrosion and effectively control low-temperature corrosion.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] This invention provides an asymmetrically arranged rotary air preheater system, comprising an economizer, an SCR reactor, a branched flue, a connecting flue, an auxiliary flue, and a rotary preheater. The bottom of the economizer is fixedly connected to one end of the auxiliary flue; the other end of the auxiliary flue is fixedly connected to the top of the rotary preheater; the bottom of the top of the economizer is fixedly connected to one end of the connecting flue; the other end of the connecting flue is fixedly connected to the top of the SCR reactor; the bottom of the SCR reactor is fixedly connected to the top of the branched flue; and the bottom of the branched flue is fixedly connected to the top of the rotary preheater.

[0007] A further technical solution of the present invention is that the branched flue includes a first flue and a second flue; a secondary economizer is provided inside the first flue.

[0008] A further technical solution of the present invention is that the rotary preheater includes a primary air rotary preheater and a secondary air rotary preheater; the top of the primary air rotary preheater is fixedly connected to the bottom of the second flue; the top of the secondary air rotary preheater is fixedly connected to the bottom of the first flue.

[0009] A further technical solution of the present invention is that a primary flue gas side compartment is provided on one side of the primary air rotary preheater; and a primary air compartment is provided on the other side of the primary air rotary preheater.

[0010] A further technical solution of the present invention is that a secondary flue gas compartment is provided on one side of the secondary air rotary preheater; and a secondary air compartment is provided on the other side of the secondary air rotary preheater.

[0011] The beneficial effects of this invention are as follows:

[0012] The asymmetrical rotary air preheater system provided by this invention reduces the exhaust gas temperature of the air preheater and does not require increasing the height of the heat exchange elements of the rotary heat exchanger. Therefore, the design resistance will not be too high, which is also conducive to the purging of the soot blower and facilitates the normal operation of the boiler. The cold end heat transfer elements of the rotary air preheater are covered with enamel, which can resist acid corrosion and effectively control low-temperature corrosion. Attached Figure Description

[0013] Figure 1 This is a front view of the asymmetrically arranged rotary air preheater system of the present invention.

[0014] Figure 2 This is a side view of the asymmetrically arranged rotary air preheater system of the present invention.

[0015] Figure 3 This is a bottom view of the asymmetrically arranged rotary air preheater system of the present invention.

[0016] In the picture:

[0017] Economizer 1; SCR reactor 2; Secondary economizer 3; Primary air rotary preheater 4; Primary flue gas side compartment 41; Primary air compartment 42; Secondary air rotary preheater 5; Secondary flue gas side compartment 51; Secondary air compartment 52; Branch flue 6; No. 1 flue 61; No. 2 flue 62; Connecting flue 7; Auxiliary flue 8; Rotary preheater 9. Detailed Implementation

[0018] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0019] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention 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. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances. Specific implementation method one:

[0021] The following is combined with Figure 1 , 2 3. Description of this embodiment: This invention relates to a preheater, more specifically, an asymmetrically arranged rotary air preheater system, including an economizer 1, an SCR reactor 2, a branched flue 6, a connecting flue 7, an auxiliary flue 8, and a rotary preheater 9. The bottom of the economizer 1 is fixedly connected to one end of the auxiliary flue 8; the other end of the auxiliary flue 8 is fixedly connected to the top of the rotary preheater 9; the top and bottom of the economizer 1 are fixedly connected to one end of the connecting flue 7; the other end of the connecting flue 7 is fixedly connected to the top of the SCR reactor 2; the bottom of the SCR reactor 2 is fixedly connected to the top of the branched flue 6; and the bottom of the branched flue 6 is fixedly connected to the top of the rotary preheater 9. This reduces the exhaust gas temperature of the air preheater, eliminates the need to increase the height of the heat exchange elements in the rotary heat exchanger 9, thus preventing excessively high design resistance and facilitating soot blowing, which in turn promotes normal boiler operation. The cold-end heat transfer elements of the rotary preheater 9 are covered with enamel, which resists acid corrosion and effectively controls low-temperature corrosion. Specific Implementation Method Two:

[0023] The following is combined with Figure 1 , 2 3. This embodiment further explains the first embodiment. The branch flue 6 includes a first flue 61 and a second flue 62. A secondary economizer 3 is installed inside the first flue 61, which reduces the flue gas temperature from 420°C to 350°C. Specific implementation method three:

[0025] The following is combined with Figure 1 , 2 3. Description of this embodiment: This embodiment further explains embodiment one. The rotary preheater 9 includes a primary air rotary preheater 4 and a secondary air rotary preheater 5. The top of the primary air rotary preheater 4 is fixedly connected to the bottom of the second flue 62. The top of the secondary air rotary preheater 5 is fixedly connected to the bottom of the first flue 61. The secondary economizer 3 reduces the flue gas temperature from 420℃ to 350℃. After heat exchange in the secondary air rotary preheater 5, the exhaust gas temperature can be reduced to 100℃. The high-temperature flue gas temperature in the second flue 62 is 420℃. After heat exchange in the small primary air rotary preheater 4, the exhaust gas temperature is 170℃. The mixed exhaust gas temperature is approximately 125℃, which is 20℃ lower than the exhaust gas temperature of the conventional arrangement. At the same time, it is not necessary to increase the height of the heat exchange elements of the rotary heat exchanger 9. Therefore, the design resistance will not be too high, which is also conducive to the purging of the soot blower and facilitates the normal operation of the boiler. Specific implementation method four:

[0027] The following is combined with Figure 1 , 2 3. This embodiment further explains the first embodiment. A primary flue gas side compartment 41 is provided on one side of the primary air rotary preheater 4; a primary air compartment 42 is provided on the other side of the primary air rotary preheater 4; the cold end heat transfer element of the rotary preheater 9 is covered with enamel, which can resist acid corrosion and effectively control low temperature corrosion. Specific implementation method five:

[0029] The following is combined with Figure 1 , 2 3. This embodiment further explains the first embodiment. A secondary flue gas compartment 51 is provided on one side of the secondary air rotary preheater 5; a secondary air compartment 52 is provided on the other side of the secondary air rotary preheater 5. The cold end heat transfer element of the rotary preheater 9 is covered with enamel, which can resist acid corrosion and effectively control low temperature corrosion.

[0030] Working principle: High-temperature flue gas flows through the flue into economizer 1 and SCR reactor 2, and is then divided into two paths through the branch flue 6. A secondary economizer 3 is installed in the first flue 61. One path of high-temperature flue gas enters the primary flue gas side compartment 41 of a small two-compartment rotary preheater 4 through the second flue 62. The other path of high-temperature flue gas enters the secondary flue gas side compartment 51 of a large two-compartment rotary preheater 5 through the secondary economizer 3. Finally, both flue gases are discharged into the atmosphere through dust removal, desulfurization, and chimneys.

[0031] The cold air is heated by the primary air compartment 42 of the small two-compartment rotary preheater and then sent to the pulverizing system to dry the coal.

[0032] The secondary cold air is heated by the secondary air compartment 52 of the large two-compartment rotary air preheater 5 and then sent to the furnace for combustion.

[0033] This invention has been described through preferred embodiments. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. This invention is not limited to the specific embodiments disclosed herein; other embodiments falling within the scope of the claims are also within the protection scope of this invention.

Claims

1. An asymmetrically arranged rotary air preheater system, characterized in that, Includes economizer, SCR reactor, branch flue, connecting flue, auxiliary flue, and rotary preheater; The lower sidewall of the economizer is fixedly connected to one end of the auxiliary flue. The other end of the auxiliary flue is fixedly connected to the top of the rotary preheater; The upper sidewall of the economizer is fixedly connected to one end of the connecting flue. The other end of the connecting flue is fixedly connected to the top of the SCR reactor; The bottom end of the SCR reactor is fixedly connected to the top end of the bifurcated flue. The bottom end of the bifurcated flue is fixedly connected to the top end of the rotary preheater; The bifurcated flue includes flue number one and flue number two; A secondary economizer is installed inside the No. 1 flue. The rotary preheater includes a small two-compartment primary air rotary preheater and a large two-compartment secondary air rotary preheater. The top of the primary air rotary preheater is fixedly connected to the bottom of the No. 2 flue. The top of the secondary air rotary preheater is fixedly connected to the bottom of the No. 1 flue.

2. The asymmetrically arranged rotary air preheater system according to claim 1, characterized in that: The primary air rotary preheater has a primary flue gas side compartment on one side. A primary air compartment is provided on the other side of the interior of the primary air rotary preheater.

3. The asymmetrically arranged rotary air preheater system according to claim 1, characterized in that: The secondary air rotary preheater has a secondary flue gas side compartment on one side. The secondary air rotary preheater has a secondary air compartment on the other side.

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