A flue gas spray cooling and water collection system

Abstract

The present invention discloses a flue gas spray cooling and water collecting system, wherein a cold water pool is located below a cooling tower, an outlet of the cold water pool is connected with a cooling water spray pipe, and the cooling water spray pipe is located at the upper part of a rear-stage ridge demister; the flue gas cooling water collecting trough is arranged on the side or bottom surface of a supporting beam of the rear-stage ridge demister, or is arranged at the lower part of the lowest point of the rear-stage ridge demister; one end of a drain pipe of the flue gas cooling water collecting trough is connected with the flue gas cooling water collecting trough, and the other end of the drain pipe of the flue gas cooling water collecting trough is inserted below the liquid level of a clarified water tank; an overflow clear water outlet at the upper part of the clarified water tank is connected with the cold water pool, and a bottom outlet of the clarified water tank is connected with an inlet of a demister flushing water pump, an outlet of the demister flushing water pump is connected with a demister spray flushing pipe, and the demister spray flushing pipe is located at the upper and lower sides of a front-stage demister, and the system can meet the full cascade utilization of demister flushing water.

Description

Technical Field

[0001] The invention belongs to the technical field of water saving and relates to a flue gas spray cooling and water collecting system. Background Art

[0002] During the wet desulfurization process, a large amount of water evaporates from the flue gas of coal-fired boilers and is discharged into the atmosphere, resulting in a huge waste of water resources. The traditional method of flue gas condensation and recycling is complex and requires high investment. Water resources are scarce in most parts of my country, especially in the north. Coal-fired boilers consume a lot of water, so it is necessary to improve the utilization rate of water resources and reduce water consumption.

[0003] Desulfurization absorption towers are generally equipped with high-efficiency ridge-type demisters, which require a large amount of water to flush the demisters. Existing technology cannot meet the full cascade utilization of demister flushing water. Therefore, it is necessary to develop cascade utilization of water resources to reduce demister flushing water consumption. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a flue gas spray cooling and water collection system, which can meet the full cascade utilization of demister flushing water and reduce the amount of demister flushing water.

[0005] To achieve the above-mentioned purpose, the flue gas spray cooling water collection system of the present invention comprises a cold water pool, a cooling tower, a cooling water spray pipeline, a rear-stage ridge demister, a flue gas cooling water collection tank, a flue gas cooling water collection tank drain pipe, a clarifying water tank, a cold water pool, a demister flushing water pump, a demister spray flushing pipeline and a front-stage demister;

[0006] The cold water pool is located below the cooling tower, and the outlet of the cold water pool is connected to the cooling water spray pipe, and the cooling water spray pipe is located above the rear-stage ridge demister;

[0007] The flue gas cooling water collection tank is arranged on the side or bottom of the supporting beam of the rear-stage ridge demister, or arranged at the lower part of the lowest point of the rear-stage ridge demister;

[0008] One end of the flue gas cooling water collecting tank drain pipe is connected to the flue gas cooling water collecting tank, and the other end of the flue gas cooling water collecting tank drain pipe is inserted below the liquid level of the clarifying water tank;

[0009] The overflow clean water outlet at the top of the clarified water tank is connected to the cold water tank, the bottom outlet of the clarified water tank is connected to the inlet of the demister flushing water pump, the outlet of the demister flushing water pump is connected to the demister spray flushing pipe, and the demister spray flushing pipe is located on the upper and lower sides of the front-stage demister.

[0010] The outlet of the cold water tank is connected to the cooling water spray pipeline through a cooling water circulation pump and a cooling water pipe.

[0011] The overflow clean water outlet at the upper part of the clarified water tank is connected to the cold water tank through an overflow water pipe.

[0012] The bottom outlet of the clarified water tank is connected to the inlet of the demister flushing water pump through the demister flushing water pump inlet valve.

[0013] The outlet of the demister flushing water pump is connected to the demister spray flushing pipeline through the demister flushing water pipe.

[0014] It also includes a clarified water tank vent valve and a desulfurization island drainage pit; the bottom outlet of the clarified water tank is connected to the desulfurization island drainage pit through the clarified water tank vent valve.

[0015] The clarified water tank is provided with a dosing device.

[0016] A liquid level meter is arranged in the clarified water tank.

[0017] The demister blades in the rear-stage ridge demister are arranged at an angle.

[0018] The present invention has the following beneficial effects:

[0019] In the specific operation of the flue gas spray cooling and water collection system of the present invention, spray cooling water in the opposite direction of the flue gas is arranged on the upper part of the rear-stage ridge demister to reduce the temperature of the saturated flue gas and generate condensed water. The spray cooling water and the condensed water after the flue gas is condensed are directed to the flue gas cooling water collection tank by using the gap between the inclined blades of the rear-stage ridge demister, and then collected in the clarification water tank for clarification, and finally the flue gas is cooled by circulating the overflow liquid, and the front-stage demister is flushed with the bottom slurry, so as to achieve the purpose of precipitating condensed water from the saturated flue gas and collecting the condensed water, and at the same time, the full cascade utilization of the demister flushing water is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A system diagram of an embodiment of the present invention.

[0021] Among them, 1 is the rear-stage ridge demister, 2 is the flue gas cooling water collecting tank, 3 is the flue gas cooling water collecting tank drain pipe, 4 is the clarified water tank, 5 is the cold water tank, 6 is the cooling water circulation pump, 7 is the cooling water pipe, 8 is the demister flushing water pump, 9 is the front-stage demister, 10 is the dosing device, 11 is the liquid level meter, 12 is the demister flushing water pump inlet valve, 13 is the demister flushing water pipe, 14 is the clarified water tank vent valve, 15 is the desulfurization island drainage pit, 16 is the overflow water pipe, and 17 is the cooling tower. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only an embodiment of a part of the present invention, not all embodiments, and is not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concepts disclosed in the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0023] The accompanying drawings show schematic diagrams of structures according to embodiments disclosed in the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0024] refer to Figure 1 The flue gas spray cooling and water collection system of the present invention comprises a cold water pool 5, a cooling tower 17, a cooling water spray pipeline, a rear-stage ridge demister 1, a flue gas cooling water collection tank 2, a flue gas cooling water collection tank drain pipe 3, a clarified water tank 4, a cold water pool 5, a demister flushing water pump 8, a demister spray flushing pipeline and a front-stage demister 8;

[0025] The cold water pool 5 is located below the cooling tower 17 , and the outlet of the cold water pool 5 is connected to the cooling water spray pipe via the cooling water circulation pump 6 and the cooling water pipe 7 , and the cooling water spray pipe is located above the rear-stage ridge demister 1 .

[0026] The flue gas cooling water collecting tank 2 is arranged on the side or bottom of the supporting beam of the rear-stage ridge demister 1 , or is arranged at the lower part of the lowest point of the rear-stage ridge demister 1 .

[0027] One end of the flue gas cooling water collecting tank drain pipe 3 is connected to the flue gas cooling water collecting tank 2, and the other end of the flue gas cooling water collecting tank drain pipe 3 is inserted below the liquid level of the clear water tank 4.

[0028] The demister blades in the rear-stage ridge demister 1 are arranged at an angle so as to guide the condensed water into the flue gas cooling water collection tank 2 .

[0029] The overflow clean water outlet at the upper part of the clarified water tank 4 is connected to the cold water tank 5 through the overflow water pipe 16 to realize the circulation of cooling water and condensed water.

[0030] The bottom of the clarified water tank 4 is connected to the inlet of the demister flushing water pump 8 through the demister flushing water pump inlet valve 12 , and the bottom of the clarified water tank 4 is connected to the desulfurization island drainage pit 15 through the clarified water tank vent valve 14 .

[0031] The outlet of the demister flushing water pump 8 is connected to the demister spray flushing pipeline through the demister flushing water pipe 13, and the demister spray flushing pipeline is located on the upper side and the lower side of the front-stage demister 8.

[0032] The clarified water tank 4 is provided with a dosing device 10 for adjusting pH and increasing the clarification speed.

[0033] The clarified water tank 4 is provided with a liquid level meter 11 for maintaining dynamic balance of the system.

[0034] The specific working process of the present invention is:

[0035] Turn on the cooling water circulation pump 6, and evenly spray the cooling water in the cold water pool 5 onto the rear-stage ridge demister 1 through the cooling water pipe 7 and the first spray water pipe, so as to evenly contact and exchange heat with the saturated flue gas, so that the saturated flue gas condenses a large amount of condensed water. The cooling water and the condensed water after the flue gas is condensed are guided to the flue gas cooling water collection tank 2 through the rear-stage ridge demister 1.

[0036] The flue gas cooling water collecting tank 2 collects the spray cooling water and the condensed water after the flue gas is condensed, and flows into the clarified water tank 4 through the flue gas cooling water collecting tank drain pipe 3.

[0037] The clear water overflowing from the upper part of the clarified water tank 4 overflows into the cold water tank 5 through the overflow pipe 16 to realize the circulation of cooling water and condensed water.

[0038] Open the demister flushing water pump inlet valve 12 at the bottom of the clarified water tank 4, start the demister flushing water pump 8, flush the front-stage demister 8 through the demister flushing water pipe 13 and the demister spray flushing pipeline, and the flushing water that has flushed the front-stage demister 8 directly falls into the absorption tower slurry pool.

[0039] According to the liquid level displayed by the liquid level meter 11, the clear water tank drain valve 14 is opened to discharge the solid water precipitated at the bottom of the clear water tank 4 to the desulfurization island drainage pit 15 to achieve dynamic balance of the system.

[0040] The main features of the present invention are:

[0041] The present invention arranges spray cooling water in the reverse direction of the flue gas on the upper part of the rear-stage ridge demister 1 to reduce the temperature of the saturated flue gas and generate condensed water. The spray cooling water and the condensed water after the flue gas is condensed are directed to the flue gas cooling water collection tank 2 by using the gaps between the inclined blades of the rear-stage ridge demister 1, and then collected to the clarification water tank 4 for clarification, and then the overflow liquid is circulated to cool the flue gas, and finally the front-stage demister 8 is flushed, so as to achieve the purpose of separating and collecting condensed water from the saturated flue gas, and significantly reduce the consumption of process water for flushing the demister.

[0042] The present invention effectively utilizes the solid-containing water precipitated at the bottom of the clarified water tank 4 to flush the front-stage demister 8, thereby realizing cascade utilization.

[0043] In addition, when the flue gas temperature is reduced, the pollutants carried in the flue gas are further reduced, making the outlet flue gas cleaner.

Claims

1. A flue gas spray cooling and water collection system, characterized in that: It comprises a cold water pool (5), a cooling tower (17), a cooling water spraying pipeline, a rear-stage ridge-type demister (1), a flue gas cooling water collecting tank (2), a flue gas cooling water collecting tank drain pipe (3), a clarifying water tank (4), a demister flushing water pump (8), a demister spraying flushing pipeline, and a front-stage demister (9); The cold water pool (5) is located below the cooling tower (17), and the outlet of the cold water pool (5) is connected to a cooling water spraying pipeline, and the cooling water spraying pipeline is located above the rear-stage ridge demister (1); The flue gas cooling water collection tank (2) is arranged on the side or bottom surface of the support beam of the rear-stage ridge demister (1), or is arranged at the lower part of the lowest point of the rear-stage ridge demister (1); One end of the flue gas cooling water collecting tank drain pipe (3) is connected to the flue gas cooling water collecting tank (2), and the other end of the flue gas cooling water collecting tank drain pipe (3) is inserted below the liquid level of the clear water tank (4); The overflow clean water outlet at the top of the clarified water tank (4) is connected to the cold water tank (5), the bottom outlet of the clarified water tank (4) is connected to the inlet of the demister flushing water pump (8), the outlet of the demister flushing water pump (8) is connected to the demister spray flushing pipeline, and the demister spray flushing pipeline is located on the upper side and the lower side of the front-stage demister (9).

2. The flue gas spray cooling and water collection system according to claim 1 is characterized in that: The outlet of the cold water pool (5) is connected to the cooling water spray pipeline via a cooling water circulation pump (6) and a cooling water pipe (7).

3. The flue gas spray cooling and water collection system according to claim 1, characterized in that: The overflow clean water outlet at the upper part of the clarified water tank (4) is connected to the cold water tank (5) through an overflow water pipe (16).

4. The flue gas spray cooling and water collection system according to claim 1, characterized in that: The bottom outlet of the clarified water tank (4) is connected to the inlet of the demister flushing water pump (8) via a demister flushing water pump inlet valve (12).

5. The flue gas spray cooling and water collection system according to claim 1, characterized in that: The outlet of the demister flushing water pump (8) is connected to the demister spray flushing pipeline via the demister flushing water pipe (13).

6. The flue gas spray cooling and water collection system according to claim 1, characterized in that: It also includes a clear water tank vent valve (14) and a desulfurization island drainage pit (15); the bottom outlet of the clear water tank (4) is connected to the desulfurization island drainage pit (15) through the clear water tank vent valve (14).

7. The flue gas spray cooling and water collection system according to claim 1, characterized in that: The clarified water tank (4) is provided with a dosing device (10).

8. The flue gas spray cooling and water collection system according to claim 1, characterized in that: A liquid level meter (11) is arranged in the clarified water tank (4).

9. The flue gas spray cooling and water collection system according to claim 1, characterized in that: The demister blades in the rear-stage ridge demister (1) are arranged at an angle.

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