Low-temperature economizer system capable of eliminating ammonium hydrogen sulfate deposition

Abstract

The utility model discloses a low-temperature coal economizer system capable of eliminating ammonium hydrogen sulfate deposition, which comprises a low-temperature coal economizer, a heating medium water inlet, a heating medium water outlet, a heating medium water inlet valve, a heating medium water outlet valve, a steam inlet, a steam inlet valve, a plurality of water drainage ports, a plurality of water drainage valves, a plurality of exhaust ports, a plurality of exhaust valves and an ash removal device, the front header of the low-temperature economizer is provided with a heating medium water outlet, a steam inlet, a water outlet and an exhaust port which are communicated with the front header, and the rear header of the low-temperature economizer is provided with an exhaust port, a heating medium water inlet and a water outlet which are communicated with the rear header. The heat exchange efficiency of low-temperature economizer equipment operation is improved, the problem that energy consumption is increased due to the fact that smoke resistance is increased after dust accumulation of the low-temperature economizer is solved, and the problem that heat exchange elements are corroded at low temperature after dust accumulation of the low-temperature economizer is solved.

Description

[Technical field]

[0001] The utility model relates to the technical field of low-temperature economizers, in particular to a low-temperature economizer system capable of eliminating ammonium hydrogen sulfate deposition. [Background technology]

[0002] The low-temperature economizer system is a waste heat recovery and utilization system. The low-temperature economizer is mainly arranged after the air preheater and before the electrostatic precipitator, and is equipped with a heat medium water auxiliary heater, a circulating water pump, a water supply system, a dust cleaning device and other auxiliary systems. The heat transfer medium is desalted water. When the heat medium water fills the entire system, the heat medium water circulation pump is started. The heat medium water enters the low-temperature economizer after being pressurized by the circulation pump to recover the waste heat of the flue gas. The heated desalted water is heated through the pipeline to heat the low-temperature flue gas after desulfurization or the cold primary and secondary air of the boiler. The desalted water is cooled and returned to the inlet of the heat medium water circulation pump.

[0003] The flue gas after the boiler passes through the SCR system and air preheater and reaches the low-temperature economizer. At present, many units have serious ammonia escape problems in the SCR system. After the flue gas passes through the air preheater, the temperature drops below 150°C, and the ammonium bisulfate in the flue gas undergoes a phase change to liquid. When it flows through the low-temperature economizer equipment, it is easy to mix with fly ash and adhere to the heat exchange element. At this time, the soot blower equipped with the traditional cleaning device cannot effectively remove the sticky ash. As time goes by, the ash accumulates more and more, which increases the resistance of the low-temperature economizer equipment and weakens the heat exchange effect. [Contents of the utility model]

[0004] The purpose of the utility model is to solve the problems in the prior art and to propose a low-temperature economizer system that can eliminate the deposition of ammonium bisulfate, so that the low-temperature economizer equipment can be cleaned without stopping the machine, thereby improving the heat exchange efficiency of the low-temperature economizer equipment, reducing the problem of increased energy consumption caused by increased flue gas resistance after ash accumulation in the low-temperature economizer, and reducing the problem of low-temperature corrosion of heat exchange components caused by ash accumulation in the low-temperature economizer.

[0005] To achieve the above-mentioned purpose, the utility model proposes a low-temperature economizer system capable of eliminating ammonium bisulfate deposition, comprising a low-temperature economizer, a heat medium water inlet, a heat medium water outlet, a heat medium water inlet valve, a heat medium water outlet valve, a steam inlet, a steam inlet valve, a plurality of drains, a plurality of drain valves, a plurality of exhaust ports, a plurality of exhaust valves and a dust cleaning device, wherein the front header of the low-temperature economizer is provided with a heat medium water outlet, a steam inlet, a drain and an exhaust port connected thereto, and the rear header of the low-temperature economizer is provided with an exhaust port, a heat medium water inlet and a drain connected thereto, and the heat medium water outlet, the steam inlet, the drain, the exhaust port and the heat medium water inlet are respectively provided with a heat medium water outlet valve, a steam inlet valve, a drain valve, an exhaust valve and a heat medium water inlet valve, and the dust cleaning device is arranged on the upper side of the low-temperature economizer for cleaning the heat exchange elements of the low-temperature economizer.

[0006] Preferably, the soot cleaning device comprises a plurality of soot blowers, and the soot blowers are connected to a compressed air or steam supply pipe.

[0007] Preferably, drain outlets are respectively provided at the lower ends of the front header and the rear header of the low-temperature economizer.

[0008] Preferably, exhaust ports are respectively provided at the upper ends of the front header and the rear header of the low-temperature economizer.

[0009] Preferably, the heat medium water outlet and the steam inlet are located between the water outlet and the air outlet, and the heat medium water outlet is located above the steam inlet.

[0010] The beneficial effects of the utility model are as follows: 1. The low-temperature economizer equipment can be cleaned without stopping the machine; 2. Existing equipment can be modified, and the modification can be performed online, with low modification cost and short construction period; 3. The heat exchange efficiency of the low-temperature economizer equipment can be improved; 4. The problem of increased energy consumption caused by increased flue gas resistance due to ash accumulation in the low-temperature economizer can be reduced; 5. The problem of low-temperature corrosion of heat exchange components due to ash accumulation in the low-temperature economizer can be reduced.

[0011] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0012] Figure 1 The utility model is a structural schematic diagram of a low-temperature economizer system capable of eliminating ammonium bisulfate deposition.

[0013] In the figure: 1- low-temperature economizer, 2- heat medium water inlet, 3- heat medium water outlet, 4- heat medium water inlet valve, 5- heat medium water outlet valve, 6- steam inlet, 7- steam inlet valve, 8- drain outlet, 9- drain valve, 10- exhaust outlet, 11- exhaust valve, 12- soot cleaning device, 121- soot blower. [Specific implementation method]

[0014] See also Figure 1The utility model discloses a low-temperature economizer system capable of eliminating ammonium bisulfate deposition, comprising a low-temperature economizer 1, a heat medium water inlet 2, a heat medium water outlet 3, a heat medium water inlet valve 4, a heat medium water outlet valve 5, a steam inlet 6, a steam inlet valve 7, a plurality of drain ports 8, a plurality of drain valves 9, a plurality of exhaust ports 10, a plurality of exhaust valves 11 and a dust cleaning device 12. The front header of the low-temperature economizer 1 is provided with a heat medium water outlet 3, a steam inlet 6, a drain port 8 and an exhaust port 10 connected thereto, the rear header of the low-temperature economizer 1 is provided with an exhaust port 10, a heat medium water inlet 2 and a drain port 8 connected thereto, the heat medium water outlet 3, the steam inlet 6, the drain port 8, the exhaust port 10 and the heat medium water inlet 2 are respectively provided with a heat medium water outlet valve 5, a steam inlet valve 7, a drain valve 9, an exhaust valve 11 and a heat medium water inlet valve 4, the dust cleaning device 12 is arranged on the upper side of the low-temperature economizer 1 for cleaning the heat exchange elements of the low-temperature economizer 1.

[0015] The soot cleaning device 12 includes a plurality of soot blowers 121 , and the soot blowers 121 are connected to a compressed air or steam supply pipe.

[0016] The lower ends of the front header and the rear header of the low-temperature economizer 1 are respectively provided with drainage ports 8 .

[0017] The upper ends of the front header and the rear header of the low-temperature economizer 1 are respectively provided with exhaust ports 10 .

[0018] The heat medium water outlet 3 and the steam inlet 6 are located between the water outlet 8 and the air outlet 10 , and the heat medium water outlet 3 is located above the steam inlet 6 .

[0019] Working process of this utility model:

[0020] The utility model discloses a low-temperature economizer system capable of eliminating ammonium bisulfate deposition. During operation, when the low-temperature economizer is seriously ash-accumulated and the equipment resistance increases, the heat medium water inlet valve 4 and the heat medium water outlet valve 5 are closed, the steam inlet valve 7 connected to the low-temperature economizer is opened, and then the drain valve 9 is opened. After steam comes out of the drain valve 9, the drain valve 9 is slowly closed to appropriately hold the pressure until distilled water is left. When the temperature of the heat exchange element rises to above the critical value of the gas-liquid phase transition of ammonium bisulfate, the ash cleaning device is opened, and the flue gas differential pressure of the low-temperature economizer is observed at the same time. The flue gas differential pressure of the low-temperature economizer is monitored by a pressure differential sensor. When the flue gas differential pressure returns to a normal value, the ash cleaning device is closed, the steam inlet valve 7 is closed, the drain valve 9 is completely closed, the exhaust valve 11 is opened, the heat medium water inlet valve 4 and the heat medium water outlet valve 5 are opened, and when water begins to flow out of the exhaust valve 11, the exhaust valve 11 is closed, and the low-temperature economizer resumes normal operation.

[0021] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention falls within the protection scope of the present invention.

Claims

1. A low temperature economizer system capable of eliminating ammonium bisulfate deposition, characterized in that: The invention comprises a low-temperature economizer (1), a heat medium water inlet (2), a heat medium water outlet (3), a heat medium water inlet valve (4), a heat medium water outlet valve (5), a steam inlet (6), a steam inlet valve (7), a plurality of drain ports (8), a plurality of drain valves (9), a plurality of exhaust ports (10), a plurality of exhaust valves (11) and a dust cleaning device (12). The front header of the low-temperature economizer (1) is provided with a heat medium water outlet (3), a steam inlet (6), a drain port (8) and an exhaust port (10) which are connected thereto. The rear header of the low-temperature economizer (1) is provided with an exhaust port (10), a heat medium water inlet (2) and a drain port (8) which are connected thereto; the heat medium water outlet (3), the steam inlet (6), the drain port (8), the exhaust port (10) and the heat medium water inlet (2) are respectively provided with a heat medium water outlet valve (5), a steam inlet valve (7), a drain valve (9), an exhaust valve (11) and a heat medium water inlet valve (4); the cleaning device (12) is provided on the upper side of the low-temperature economizer (1) for cleaning the heat exchange elements of the low-temperature economizer (1).

2. A low-temperature economizer system capable of eliminating ammonium bisulfate deposition as claimed in claim 1, characterized in that: The soot cleaning device (12) comprises a plurality of soot blowers (121), and the soot blowers (121) are connected to a compressed air or steam supply pipe.

3. A low-temperature economizer system capable of eliminating ammonium bisulfate deposition as claimed in claim 1, characterized in that: The lower ends of the front header and the rear header of the low-temperature economizer (1) are respectively provided with drainage outlets (8).

4. A low-temperature economizer system capable of eliminating ammonium bisulfate deposition as claimed in claim 1, characterized in that: The upper ends of the front header and the rear header of the low-temperature economizer (1) are respectively provided with exhaust ports (10).

5. A low-temperature economizer system capable of eliminating ammonium bisulfate deposition according to any one of claims 1 to 4, characterized in that: The heat medium water outlet (3) and the steam inlet (6) are located between the water outlet (8) and the air outlet (10), and the heat medium water outlet (3) is located above the steam inlet (6).

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