CN211274153U - A boiler flue gas dewhitening device - Google Patents

Abstract

The utility model relates to a boiler flue gas dewhitening device, which comprises a desulfurization wet electric device and a tail chimney, and a flue gas dewhitening device is arranged between them. The upper part of the heat exchanger provided in the flue gas dewhitening device passes through a flue gas pipeline Connect the desulfurization wet-electric equipment, the side of the heat exchanger is connected with a cooling fan, and the side of the heat exchanger near the rear chimney is provided with a cooling air outlet. There is a re-heater, one side of the re-heater is connected to the pipeline at the lower part of the heat exchanger through a pipeline, which is used to discharge the flue gas with low moisture content. The pipe is connected to the tail chimney; the flue gas dewhitening device designed by the utility model is condensed and then heated to keep the flue gas away from the saturated state. The flue gas phase is mixed, and no white smoke can be seen during the exhaust process.

Description

A boiler flue gas dewhitening device

technical field

The utility model relates to the technical field of flue gas treatment, in particular to a boiler flue gas dewhitening device.

Background technique

Since the boiler flue gas contains a large amount of water vapor, when the hot flue gas of the boiler is discharged into the atmosphere and encounters the ambient cold air, heat exchange will occur; when the flue gas temperature drops to the saturation temperature, the water vapor in the flue gas will It begins to condense into tiny water droplets. As the temperature of the flue gas decreases further, more water vapor will condense into a large number of tiny water droplets, which looks like white smoke to the naked eye. In order to eliminate the phenomenon of "white smoke", reduce the possibility of condensation in the chimney, and increase the elevation of the flue gas to enhance the diffusion of the flue gas, a flue gas dewhitening device is installed in front of the tail chimney and after the desulfurization wet electrostatic device to make the exhaust humidity. The temperature of the exhaust gas is lowered to make the exhaust gas temperature higher than the saturation temperature under the humidity, thereby eliminating the visual white smoke, and at the same time, during the condensation process of the flue gas, the harmful substances (SO2, dust, etc.) in the flue gas are further reduced.

Utility model content

The utility model is proposed to solve the problems in the prior art, and its purpose is to provide a boiler flue gas dewhitening device, which realizes simple operation, short cleaning time, energy saving and emission reduction.

A boiler flue gas dewhitening device includes desulfurization wet electric equipment and a tail chimney, a flue gas dewhitening device is arranged between the desulfurization wet electric equipment and the tail chimney, and the upper part of the heat exchanger provided in the flue gas dewhitening device passes through the upper part of the heat exchanger. The flue gas pipeline is connected to the desulfurization wet electric equipment, the cooling fan is connected to one side of the heat exchanger, the cooling air outlet is provided on the side of the heat exchanger close to the tail chimney, and the cooling air outlet is connected to the tail through the cooling air outlet pipe The chimney, the pipe at the bottom of the heat exchanger is provided with a water outlet for discharging condensed water, the water outlet is connected with an external condensed water collection system, a reheater is arranged below the cooling air outlet pipe, the One side of the reheater is connected to the pipeline at the lower part of the heat exchanger through a pipeline, which is used to discharge the flue gas with low moisture content. The reheater is provided with a hot air outlet on the side close to the chimney at the rear, and the hot air outlet exits through the hot air. The air duct is connected to the rear chimney.

Preferably, the heat exchanger adopts a plate heat exchanger, and is constructed using an all-welding technology.

Preferably, the pipe provided outside the heat exchanger is in the shape of a frustum, and the upper part of the pipe is connected to the flue gas pipe.

Preferably, the bottom of the pipe outside the heat exchanger is inclined toward the drain port, so that the condensed water can quickly and completely enter the condensed water collection system.

Preferably, a plurality of spray devices for humidification are provided inside the desulfurization wet electric equipment.

Preferably, the bottom of the desulfurization wet electric equipment is provided with a flue gas inlet for entering the flue gas.

Preferably, the tail chimney includes an external mixed tail gas outer chimney and an internal tail gas inner chimney, the tail gas inner chimney is located inside the mixed tail gas outer chimney, and the height and diameter of the tail gas inner chimney are smaller than the mixed tail gas outer chimney.

Preferably, the cooling air outlet duct is connected to the outer chimney of the mixed exhaust gas, and the hot air outlet duct is connected to the inner chimney of the exhaust gas.

In the boiler flue gas dewhitening device of the utility model, the device first condenses and then heats up, first condenses a part of the water vapor in the flue gas, the purpose is to reduce the saturation temperature of the flue gas, and then slightly heat the flue gas to keep the flue gas away from the saturated state , the flue gas with reduced moisture content is heated through the flue gas reheater and introduced into the end of the chimney to mix with the flue gas after cooling and dehydration. No white smoke can be seen during the exhaust process, and the structure is simple and easy to implement; The heat exchange effect of the heat exchanger is better, and the gap between the plates of the plate heat exchanger is relatively large, which greatly reduces the probability of blockage and facilitates later cleaning; the designed condensate water collection system realizes preheating and recycling, waste utilization, Energy saving and emission reduction; and can effectively remove sulfur dioxide, nitrogen oxides, suspended particulate matter and other substances in the smoke.

Description of drawings

Figure 1 is a schematic structural diagram of the utility model.

Description of reference numerals

1- Desulfurization wet electric equipment; 2- Flue gas pipeline; 3- Spray equipment; 4- Cooling fan; 5- Heat exchanger; 6- Cooling air outlet pipe; 7- Condensate collection system; 8- Reheater ; 9- hot air outlet pipe; 10- tail gas inner chimney; 11- mixed tail gas outer chimney.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

The embodiment of the present utility model, referring to FIG. 1, a boiler flue gas dewhitening device, including desulfurization wet electric equipment 1 and a tail chimney, a flue gas dewhitening device is arranged between the desulfurization wet electric equipment 1 and the tail chimney, and the flue gas The upper part of the heat exchanger 5 provided in the de-whitening device is connected to the desulfurization wet electric equipment 1 through the flue gas pipeline 2, the cooling fan 4 is connected to one side of the heat exchanger 5, and the side of the heat exchanger 5 close to the tail chimney is provided with a cooling air outlet, The cooling air outlet is connected to the tail chimney through the cooling air outlet pipe 6, which is used to discharge the flue gas after cooling and dehydration. The pipe at the bottom of the heat exchanger 5 is provided with a drain port for draining condensed water, and the drain port is connected with external condensed water. In the collection system 7, a re-heater 8 is provided below the cooling air outlet duct 6, and one side of the re-heater 8 is connected to the pipeline at the lower part of the heat exchanger 5 through a pipeline to discharge the flue gas with low moisture content, and the re-heater 8 A hot air outlet is provided on the side near the rear chimney, and the hot air outlet is connected to the rear chimney through a hot air outlet pipe 9 .

The rear chimney includes an outer mixed exhaust chimney 11 and an internal exhaust chimney 10, the inner chimney 10 is located inside the outer chimney 11 of the mixed exhaust, and the height and diameter of the inner chimney 10 are smaller than the outer chimney 11 of the mixed exhaust; the cooling air The air outlet pipe 6 is connected to the outer chimney 11 of the mixed exhaust gas, and the hot air outlet pipe 9 is connected to the inner exhaust gas chimney 10, which is used for the flue gas after the flue gas with reduced moisture content is heated up through the flue gas reheater and introduced into the end of the chimney and cooled and dehydrated. mixed.

The heat exchanger adopts a plate heat exchanger and is constructed by all-welding technology; the pipes provided outside the heat exchanger are truncated cones, and the upper part of the pipes is connected to the flue gas pipe; the bottom of the pipes outside the heat exchanger is a drain port The direction is inclined to allow the condensate to enter the condensate collection system quickly and completely. The desulfurization wet electric equipment is equipped with a plurality of spray devices for humidification, and the bottom of the desulfurization wet electric equipment is provided with a flue gas inlet.

On the basis of wet power and desulfurization, the method of cooling and condensation is adopted, that is, the flue gas is condensed by the cooling fan in the heat exchanger, and one part of the wind becomes condensed water and enters the condensed water collection system through the drainage port below, and part of it is condensed to cool down. The dehydrated flue gas enters the mixed exhaust gas outer chimney 11 through the cooling air outlet duct 6 , and a part of the flue gas with reduced moisture content is heated by the reheater 8 and introduced into the exhaust gas inner chimney 10 . While reducing the temperature of the flue gas, the water vapor in the saturated flue gas is condensed, and a large amount of water is condensed, and then the physical and chemical precipitation process is used for treatment. After sedimentation, it can be discharged into the desulfurization water tank for recycling. The flue gas with reduced moisture content is heated through the flue gas reheater and introduced into the end of the chimney to be mixed with the flue gas after cooling and dehydration, so that the moisture content and relative humidity of the mixed flue gas are greatly reduced, thereby reducing the exhaust gas. The dew point temperature of the air flue gas makes the exhaust flue gas not reach the dew point temperature within a short time after it is discharged, and the moisture in the exhaust gas will not condense into water mist, thereby achieving the purpose of reducing white smoke.

The device of the utility model realizes that the plate heat exchanger adopts the all-welding technology structure, and its structure is special, and the heat exchange effect is improved by more than 30% compared with the traditional plate heat exchanger; The gap between them is relatively large, which greatly reduces the probability of blockage and facilitates later cleaning; strong corrosion resistance: for special media, corrosion-resistant materials are used, which are resistant to dilute sulfuric acid, HCL gas, etc., effectively solving corrosion problems; realizing waste heat reuse : Realize waste heat reuse, and design waste heat utilization according to different working conditions and different temperatures. According to calculations, after waste heat is used, fuel costs are saved every year and investment costs are reduced; the removal rate of other substances in flue gas is high: after testing, the flue gas passes through After the whitening device, sulfur dioxide, nitrogen oxides and suspended particulate matter are reduced to a certain extent, and the average removal rate is above 50%.

It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any relationship between these entities or operations. any such actual relationship or sequence exists. Moreover, the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device that includes a list of elements includes not only those elements, but also includes not explicitly listed or other elements inherent to such a process, method, article or apparatus.

Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes and modifications can be made to these embodiments without departing from the principles and spirit of the present invention , alternatives and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (8)

1. a boiler flue gas dewhitening device, comprising desulfurization wet electric equipment (1) and a tail chimney, it is characterized in that, between the desulfurization wet electric equipment (1) and the tail chimney, a flue gas dewhitening device is provided, and the smoke The upper part of the heat exchanger (5) provided in the gas dewhitening device is connected to the desulfurization wet electric equipment (1) through the flue gas pipeline (2), and a cooling fan (4) is connected to one side of the heat exchanger (5). The side of the heat exchanger (5) close to the tail chimney is provided with a cooling air outlet, and the cooling air outlet is connected to the tail chimney through the cooling air outlet pipe (6). A water outlet for discharging condensed water, the water outlet is connected with an external condensed water collection system (7), and a reheater (8) is provided below the cooling air outlet pipe (6), and the reheater (8) ) is connected to the pipe at the lower part of the heat exchanger (5) through a pipe to discharge the flue gas with low moisture content, and the reheater (8) is provided with a hot air outlet near the side of the rear chimney, and the hot air The outlet is connected to the tail chimney through a hot air outlet pipe (9). 2 . The boiler flue gas dewhitening device according to claim 1 , wherein the heat exchanger ( 5 ) adopts a plate-type heat exchanger, and is constructed using an all-welding technology. 3 . 3 . The boiler flue gas dewhitening device according to claim 1 , wherein the pipes provided outside the heat exchanger ( 5 ) are truncated cones, and the upper part of the pipes is connected to the flue gas pipes ( 2 ). 4 . 4. The boiler flue gas dewhitening device according to claim 3, wherein the bottom of the pipe outside the heat exchanger (5) is inclined to the direction of the water outlet, for the condensed water to enter the condensed water collection system ( 7). 5. The boiler flue gas dewhitening device according to claim 1, characterized in that, a plurality of spray devices for humidification are arranged inside the desulfurization wet electric equipment (1). 6. The boiler flue gas dewhitening device according to claim 5, characterized in that, the bottom of the desulfurization wet electric equipment (1) is provided with a flue gas inlet for entering the flue gas. 7. The boiler flue gas dewhitening device according to claim 1, wherein the tail chimney comprises an external mixed tail gas outer chimney (11) and an internal tail gas inner chimney (10), and the tail gas inner chimney (10) It is located inside the mixed tail gas outer chimney (11), and the height and diameter of the mixed tail gas inner chimney (10) are smaller than those of the mixed tail gas outer chimney (11). 8. The boiler flue gas dewhitening device according to claim 7, wherein the cooling air outlet pipe (6) communicates with the outer chimney (11) of the mixed exhaust gas, and the hot air outlet pipe (9) communicates with the inner chimney of the exhaust gas. (10).

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