阅读说明：本技术 一种脱硫废水处理系统及脱硫废水处理方法 (Desulfurization wastewater treatment system and desulfurization wastewater treatment method ) 是由 李剑 张彩端 夏阳 于 2021-09-24 设计创作，主要内容包括：本申请公开了一种脱硫废水处理系统及脱硫废水处理方法。所述脱硫废水处理系统包括：空预器,所述空预器包括底部高温气体排气空间；脱硫废水排水管,所述脱硫废水排水管的排水端与所述高温气排气空间连通,脱硫废水自所述脱硫废水排水管进入至所述高温气排气空间内。本申请通过利用烟气余热实现了脱硫废水的固化零排,节省了蒸发结晶固化所需的蒸汽耗量,节约了运行成本；无需进行干燥塔的建设,节省了初期投资和占地；在保证了脱硫废水的零排需求的条件下,最大程度的减少了对电厂锅炉效率的影响。(The application discloses desulfurization wastewater treatment system and desulfurization wastewater treatment method. The desulfurization wastewater treatment system includes: the air preheater comprises a bottom high-temperature gas exhaust space; and the drainage end of the desulfurization wastewater drainage pipe is communicated with the high-temperature gas exhaust space, and the desulfurization wastewater enters the high-temperature gas exhaust space from the desulfurization wastewater drainage pipe. The method realizes the solidification zero discharge of the desulfurization wastewater by using the waste heat of the flue gas, saves the steam consumption required by evaporative crystallization solidification, and saves the operation cost; the construction of a drying tower is not needed, so that the initial investment and the occupied area are saved; under the condition of ensuring the zero discharge requirement of the desulfurization wastewater, the influence on the efficiency of the power plant boiler is reduced to the greatest extent.)

1. A desulfurization wastewater treatment system, characterized in that it comprises:

the air preheater (1), the air preheater (1) comprises a bottom high-temperature gas exhaust space (11);

and the water discharging end of the desulfurization waste water discharging pipe (2) is communicated with the high-temperature gas exhaust space (11), and the desulfurization waste water enters the high-temperature gas exhaust space (11) from the desulfurization waste water discharging pipe.

2. The desulfurization wastewater treatment system of claim 1, further comprising:

the desulfurization waste water storage device comprises a waste water storage device (3), wherein the water outlet end of the waste water storage device (3) is communicated with the water inlet end of a desulfurization waste water drainage pipe (2), and desulfurization waste water is stored in the waste water storage device (3).

3. The desulfurization wastewater treatment system of claim 2, further comprising:

and the heating device (4) wraps the desulfurization wastewater drain pipe (2) and is used for heating the desulfurization wastewater flowing through the desulfurization wastewater drain pipe (2).

4. The desulfurization wastewater treatment system of claim 3, further comprising:

booster pump (5), the input of booster pump (5) with the play water end of waste water storage device (3) is connected, the output of booster pump (5) with desulfurization waste water drain pipe's the end intercommunication of intaking, booster pump (5) be used for with pump income behind the desulfurization waste water pressure boost in waste water storage device (3) desulfurization waste water drain pipe.

5. The desulfurization wastewater treatment system of claim 4, further comprising:

atomizing nozzle (6), the quantity of atomizing nozzle (6) is a plurality of, each atomizing nozzle (6) all sets up on getting into the partial desulfurization waste water drain pipe of air preheater.

6. The desulfurization waste water treatment system of claim 5, wherein said desulfurization waste water discharge pipe is formed using a flexible hose.

7. The desulfurization waste water treatment system according to claim 6, wherein an observation window (8) is provided in the air preheater for observing the atomization and solidification of the desulfurization waste water in the high-temperature gas exhaust space in the air preheater.

8. The desulfurization waste water treatment system according to claim 7, wherein said atomizing nozzle comprises a first water inlet (61), a second water inlet (62), and a first water outlet (63), said first water outlet (63), first water inlet (61), and second water inlet (62) being in communication with each other;

the first water inlet (61) is communicated with the desulfurization waste water drain pipe (2);

the desulfurization wastewater treatment system further comprises a cleaning water pipeline (7), wherein the cleaning water pipeline (7) is communicated with the second water inlet (62).

9. A desulfurization wastewater treatment method for the desulfurization wastewater treatment system according to any one of claims 1 to 8, characterized by comprising:

and discharging the desulfurization wastewater in the desulfurization wastewater discharge pipe into a high-temperature exhaust space at the bottom of the air preheater so as to solidify the desulfurization wastewater through higher-temperature gas in the high-temperature exhaust space.

10. The desulfurization wastewater treatment method according to claim 9, further comprising:

and in the process that the desulfurization wastewater in the desulfurization wastewater drainage pipe is discharged into the high-temperature exhaust space at the bottom of the air preheater, the desulfurization wastewater flowing through the desulfurization wastewater drainage pipe is heated by the heating device.

Technical Field

The application relates to the technical field of power plant desulfurization wastewater treatment, in particular to a desulfurization wastewater treatment system and a desulfurization wastewater treatment method.

Background

The power plant desulfurization mainly comprises a limestone-gypsum wet desulfurization process, the process is mature in technology and high in adaptability, but because the enrichment of chloride ions and heavy metals in the circulating process can greatly influence the desulfurization efficiency and the gypsum quality, a desulfurization system needs to discharge desulfurization wastewater periodically, the discharged desulfurization wastewater has the characteristics of weak acidity, high content of suspended matters and high salt content, the direct discharge can cause environmental pollution, and then each plant is provided with a triple box to treat and discharge the desulfurization wastewater. However, the mode of treating and discharging the desulfurization wastewater is limited along with the promulgation and implementation of ten items of water in recent years, so that the pressure of thermal power plants as water consumers in the aspects of water resource restriction and discharge limitation is suddenly improved, and the achievement of deep water saving and zero discharge of wastewater becomes a necessary choice.

At present, the 'zero discharge' technology of the desulfurization wastewater of the thermal power plant in China mainly comprises the following two routes: the first route is 'pretreatment + membrane method concentration + evaporative crystallization', the technology is mature, but the pretreatment in the early stage needs to be added with chemicals, the dosage needs to be changed continuously according to the fluctuation of the water quality of the desulfurization wastewater, and once the dosage is not accurately controlled, the membrane element is easy to be polluted and blocked, so that the higher replacement and maintenance cost is caused; the second route is 'hot concentration technology + flue spray drying', the technology does not need to pretreat the desulfurization wastewater, and directly carries out negative pressure evaporation concentration to realize the recycling of part of water, a small amount of residual concentrated wastewater is directly sprayed into a flue or a bypass drying tower is established to extract part of flue gas to carry out solidification zero discharge of the desulfurization wastewater, the aim of zero discharge of the desulfurization wastewater is realized by utilizing the waste heat of the flue gas, but the direct injection flue technology is easy to corrode or deposit ash to block the flue, the bypass flue technology not only needs to establish a set of newly-built evaporation tower equipment, but also can cause different degrees of influence on the boiler efficiency due to different extracted flue gas positions.

Because the bypass flue technology at the present stage mainly utilizes the high-temperature flue gas in front of the air preheater or the low-temperature flue gas in front of the dust remover, if the high-temperature flue gas in front of the air preheater is extracted as a heat source to perform zero discharge of desulfurization wastewater, although the amount of the extracted flue gas is small, the efficiency of the power plant boiler can be reduced; if low-temperature flue gas in front of the dust remover is extracted, the required flue gas amount is large, and the power generation coal consumption of a power plant is increased.

Therefore, in order to avoid high investment and operation cost in the technologies of pretreatment, membrane concentration and evaporative crystallization, a thermal method concentration technology and a flue spraying technology are mainly selected, but in the existing technology for treating a small amount of residual desulfurization wastewater after concentration, most of low-temperature flue gas is used for solidification and zero emission, and the technology has the risk of blocking a flue or corroding the flue by deposited ash.

Accordingly, a technical solution is desired to overcome or at least alleviate at least one of the above-mentioned drawbacks of the prior art.

Disclosure of Invention

It is an object of the present application to provide a desulphurisation wastewater treatment system which overcomes or at least alleviates at least one of the above-mentioned disadvantages of the prior art.

To achieve the above object, the present application provides a desulfurization wastewater treatment system comprising:

the air preheater comprises a bottom high-temperature gas exhaust space;

and the drainage end of the desulfurization wastewater drainage pipe is communicated with the high-temperature gas exhaust space, and the desulfurization wastewater enters the high-temperature gas exhaust space from the desulfurization wastewater drainage pipe.

Optionally, the desulfurization wastewater treatment system further comprises:

the water outlet end of the waste water storage device is communicated with the water inlet end of the desulfurization waste water drainage pipe, and desulfurization waste water is stored in the waste water storage device.

Optionally, the desulfurization wastewater treatment system further comprises:

and the heating device wraps the desulfurization wastewater drainage pipe and is used for heating the desulfurization wastewater flowing through the desulfurization wastewater drainage pipe.

Optionally, the desulfurization wastewater treatment system further comprises:

the input of booster pump with waste water storage device's play water end is connected, the output of booster pump with desulfurization waste water drain pipe's the end intercommunication of intaking, the booster pump be used for with go into behind the desulfurization waste water pressure boost in the waste water storage device desulfurization waste water drain pipe.

Optionally, the desulfurization wastewater treatment system further comprises:

the atomizing nozzle, atomizing nozzle's quantity is a plurality of, each atomizing nozzle all sets up on getting into the partial desulfurization waste water drain pipe of air preheater.

Optionally, the desulfurization waste water discharge pipe is made of a telescopic hose.

Optionally, the air preheater is provided with an observation window for observing the atomization and solidification of the desulfurization wastewater in the high-temperature gas exhaust space in the air preheater.

Optionally, the nozzle includes a first water inlet, a second water inlet, and a first water outlet, and the first water outlet, the first water inlet, and the second water inlet are communicated with each other;

the first water inlet is communicated with the desulfurization wastewater drainage pipe;

the desulfurization wastewater treatment system further comprises a cleaning water pipeline, and the cleaning water pipeline is communicated with the second water inlet.

The application also provides a desulfurization wastewater treatment method, which is used for the desulfurization wastewater treatment system and comprises the following steps:

and discharging the desulfurization wastewater in the desulfurization wastewater discharge pipe into a high-temperature exhaust space at the bottom of the air preheater so as to solidify the desulfurization wastewater through higher-temperature gas in the high-temperature exhaust space.

Optionally, the desulfurization wastewater treatment method further comprises:

and in the process that the desulfurization wastewater in the desulfurization wastewater drainage pipe is discharged into the high-temperature exhaust space at the bottom of the air preheater, the desulfurization wastewater flowing through the desulfurization wastewater drainage pipe is heated by the heating device.

The desulfurization wastewater treatment system directly sprays desulfurization wastewater into the air preheater, and the flue gas side high-temperature gas at the bottom of the air preheater after heat exchange is sprayed, by adopting the mode, the rotary heat exchange performance of the air preheater is utilized, because the flue gas flowing direction in the air preheater is from top to bottom, and the air flowing direction is from bottom to top, the flue gas temperature at the upper part of the air preheater is higher than that at the lower part, the main structure of the air preheater is considered to be distributed into the flue gas side, the air side and the sealing side, wherein 1/2 is the flue gas side, 30-40% of the air side and the rest of the air side are sealing areas, when the heat exchange plate cooled by air is rotated to the flue gas side through a rotating shaft, the heat exchange plate is heated, low-temperature flue gas is discharged, but the temperature difference between the cooled heat exchange plate and the flue gas when the cooled heat exchange plate is rotated to the flue gas side at the beginning is the largest, the heat exchange is fastest, the temperature of the flue gas flowing through the air preheater is the lowest, and rotates along with the plate, the difference in temperature of heat transfer board and flue gas is more and more littleer, then the heat transfer is more and more few, and the air preheater will exhaust flue gas temperature more and more high flowing through, and this application utilizes the flue gas of this part higher temperature to carry out the concentration of desulfurization waste water, neither can cause the high temperature flue gas consumption of not heat transfer before the air preheater, can not influence waste water evaporation because of the low temperature flue gas temperature of the whole mixings of discharge air preheater again.

Drawings

FIG. 1 is a schematic configuration diagram of a desulfurization wastewater treatment system according to a first embodiment of the present application.

FIG. 2 is another schematic view showing the construction of a desulfurization waste water treatment system according to the first embodiment of the present application.

Reference numerals:

1. an air preheater; 11. a high-temperature gas exhaust space; 2. a desulfurization waste water drain pipe; 3. a waste water storage device; 4. a heating device; 5. a booster pump; 6. an atomizing nozzle; 61. a first water inlet; 62. a second water inlet; 63. a first water outlet; 7. cleaning a water pipeline; 8-observation window.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are a subset of the embodiments in the present application and not all embodiments in the present application. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application. Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

In the description of the present application, it is to be understood that the terms "central," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner and are not to be considered limiting of the scope of the present application.

FIG. 1 is a schematic configuration diagram of a desulfurization wastewater treatment system according to a first embodiment of the present application. FIG. 2 is another schematic view showing the construction of a desulfurization waste water treatment system according to the first embodiment of the present application.

The desulfurization waste water treatment system shown in fig. 1 and 2 includes an air preheater 1 and a desulfurization waste water discharge pipe 2, wherein the air preheater 1 includes a bottom high-temperature gas exhaust space 11; the water discharge end of the desulfurization waste water discharge pipe 2 is communicated with the high-temperature gas exhaust space 11, and desulfurization waste water enters the high-temperature gas exhaust space 11 from the desulfurization waste water discharge pipe.

The desulfurization wastewater treatment system directly sprays desulfurization wastewater into the air preheater, and the flue gas side high-temperature gas at the bottom of the air preheater after heat exchange is sprayed, by adopting the mode, the rotary heat exchange performance of the air preheater is utilized, because the flue gas flowing direction in the air preheater is from top to bottom, and the air flowing direction is from bottom to top, the flue gas temperature at the upper part of the air preheater is higher than that at the lower part, the main structure of the air preheater is considered to be distributed into the flue gas side, the air side and the sealing side, wherein 1/2 is the flue gas side, 30-40% of the air side and the rest of the air side are sealing areas, when the heat exchange plate cooled by air is rotated to the flue gas side through a rotating shaft, the heat exchange plate is heated, low-temperature flue gas is discharged, but the temperature difference between the cooled heat exchange plate and the flue gas when the cooled heat exchange plate is rotated to the flue gas side at the beginning is the largest, the heat exchange is fastest, the temperature of the flue gas flowing through the air preheater is the lowest, and rotates along with the plate, the difference in temperature of heat transfer board and flue gas is more and more littleer, then the heat transfer is more and more few, and the air preheater will exhaust flue gas temperature more and more high flowing through, and this application utilizes the flue gas of this part higher temperature to carry out the concentration of desulfurization waste water, neither can cause the high temperature flue gas consumption of not heat transfer before the air preheater, can not influence waste water evaporation because of the low temperature flue gas temperature of the whole mixings of discharge air preheater again.

Referring to fig. 1, in the present embodiment, the desulfurization waste water treatment system further includes a waste water storage device 3, an outlet end of the waste water storage device 3 is communicated with an inlet end of the desulfurization waste water discharge pipe 2, and desulfurization waste water is stored in the waste water storage device 3.

Referring to fig. 1, in the present embodiment, the desulfurization waste water treatment system further includes a heating device 4, and the heating device 4 is wrapped around the desulfurization waste water discharge pipe 2 and is used for heating the desulfurization waste water flowing through the desulfurization waste water discharge pipe 2.

By adopting the mode, the desulfurization wastewater is preheated before entering the high-temperature gas exhaust space, the preheating temperature is the boiling point temperature of the wastewater, the wastewater is ensured to be directly vaporized after being sprayed into the air preheater, the vaporization time is accelerated, and the time for heating the wastewater is shortened

In this embodiment, desulfurization waste water treatment system further includes booster pump 5, and booster pump 5's input is connected with waste water storage device 3's play water end, and booster pump 5's output and desulfurization waste water drain pipe's the end intercommunication of intaking, and booster pump 5 is used for pumping into behind the desulfurization waste water pressure boost in waste water storage device 3 desulfurization waste water drain pipe.

Make desulfurization waste water area pressure get into the air preheater through the booster pump, guarantee the atomization effect of waste water, and then guarantee that waste water accomplishes the vaporization in short time.

Referring to fig. 1, in the present embodiment, the desulfurization waste water treatment system further includes a plurality of atomizing nozzles 6, and each atomizing nozzle 6 is disposed on a part of the desulfurization waste water discharge pipe entering the air preheater. .

Can diversified spout into desulfurization waste water to high temperature gas exhaust space through a plurality of atomizing nozzle to can utilize the high temperature gas in the high temperature gas exhaust space to the at utmost.

Referring to fig. 1, in the present embodiment, the desulfurization waste water discharge pipe is made of a flexible hose.

Adopt telescopic hose, can guarantee that the spray pipe can retrieve when the power plant carries out normal air preheater and washs, do not influence abluent going on.

It is understood that in other embodiments, the desulfurization waste water discharge pipe can also adopt a plurality of telescopic pipes, and in this case, the pipes can adopt hard pipes.

Referring to fig. 1, in the present embodiment, an observation window 8 is provided on the air preheater for observing the atomization and solidification of the desulfurization wastewater in the high-temperature gas exhaust space in the air preheater.

Through set up the viewing aperture in air preheater nozzle position, observe the atomizing and the solidification effect of desulfurization waste water constantly, avoid appearing waste water and directly fall into below ash bucket with the form of liquid drop, cause the deposition in the ash bucket to harden.

Referring to fig. 1, in the present embodiment, the atomizing nozzle includes a first water inlet 61, a second water inlet 62 and a first water outlet 63, and the first water outlet 63, the first water inlet 61 and the second water inlet 62 are communicated with each other; the first water inlet 61 is communicated with the desulfurization waste water drain pipe 2; the desulfurization waste water treatment system further includes a clean water supply pipe 7, and the clean water supply pipe 7 is communicated with the second water inlet 62.

By adopting the structure, the atomizing nozzle is connected with two pipelines, one pipeline is the desulfurization wastewater and is used for atomizing the desulfurization wastewater; one way is a cleaning water pipeline which is used for cleaning the nozzle (a self-cleaning device of the system) and preventing the nozzle from being blocked by the crystal salt.

In one embodiment, the spray pipe is arranged in a herringbone roof ridge form, so that the distribution of the desulfurization waste water is ensured, and the desulfurization waste water is prevented from directly falling into the ash bucket.

In this embodiment, the atomizing nozzle further comprises a first electromagnetic valve and a second electromagnetic valve, the first electromagnetic valve is arranged at the first water inlet, and the first electromagnetic valve can cut off or communicate the communication between the first water inlet and the desulfurization wastewater discharge pipe; the second solenoid valve sets up at the second water inlet, and the second solenoid valve can cut off or communicate the second water inlet and provide the intercommunication of pipeline with clean water.

Through the control of first solenoid valve and second solenoid valve, can prevent that desulfurization waste water from getting into clean water supply pipeline or prevent that clean water from getting into desulfurization waste water pipeline.

In this embodiment, the air preheater 1 is a three-compartment rotary air preheater, which is a heat storage type air preheater, and when the rotor rotates, the flue gas and the air alternately pass through the heat storage element, and when the flue gas passes through the heat storage element, the heat absorption surface absorbs heat, and the flue gas is transferred to the air side heat absorption surface to release heat, so as to heat the air, and the circulation is performed. Because the heat storage element cooled by air rotates to enter the smoke side for heating, the temperature of the heated surface is continuously increased along with the rotation of the heat storage element, namely, the temperature of the smoke flowing through is reduced, the temperature of the smoke flowing out of the channel is increased, and the position with the highest smoke temperature is positioned in the high-temperature exhaust space 11.

The method realizes solidification zero discharge of the desulfurization wastewater by using the waste heat of the flue gas, saves the steam consumption required by evaporative crystallization, and saves the operation cost; the construction of a drying tower is not needed, so that the initial investment and the occupied area are saved; under the condition of ensuring the zero discharge requirement of the desulfurization wastewater, the influence on the efficiency of the power plant boiler is reduced to the greatest extent.

The application also provides a desulfurization wastewater treatment method, which is used for the desulfurization wastewater treatment system and comprises the following steps:

and discharging the desulfurization wastewater in the desulfurization wastewater discharge pipe into a high-temperature exhaust space at the bottom of the air preheater so as to solidify the desulfurization wastewater through higher-temperature gas in the high-temperature exhaust space.

In this embodiment, the desulfurization wastewater treatment method further includes:

and in the process that the desulfurization wastewater in the desulfurization wastewater drainage pipe is discharged into the high-temperature exhaust space at the bottom of the air preheater, the desulfurization wastewater flowing through the desulfurization wastewater drainage pipe is heated by the heating device.

The desulfurization wastewater treatment system directly sprays desulfurization wastewater into the air preheater, and the flue gas side high-temperature gas at the bottom of the air preheater after heat exchange is sprayed, by adopting the mode, the rotary heat exchange performance of the air preheater is utilized, because the flue gas flowing direction in the air preheater is from top to bottom, and the air flowing direction is from bottom to top, the flue gas temperature at the upper part of the air preheater is higher than that at the lower part, the main structure of the air preheater is considered to be distributed into the flue gas side, the air side and the sealing side, wherein 1/2 is the flue gas side, 30-40% of the air side and the rest of the air side are sealing areas, when the heat exchange plate cooled by air is rotated to the flue gas side through a rotating shaft, the heat exchange plate is heated, low-temperature flue gas is discharged, but the temperature difference between the cooled heat exchange plate and the flue gas when the cooled heat exchange plate is rotated to the flue gas side at the beginning is the largest, the heat exchange is fastest, the temperature of the flue gas flowing through the air preheater is the lowest, and rotates along with the plate, the difference in temperature of heat transfer board and flue gas is more and more littleer, then the heat transfer is more and more few, and the air preheater will exhaust flue gas temperature more and more high flowing through, and this application utilizes the flue gas of this part higher temperature to carry out the concentration of desulfurization waste water, neither can cause the high temperature flue gas consumption of not heat transfer before the air preheater, can not influence waste water evaporation because of the low temperature flue gas temperature of the whole mixings of discharge air preheater again.

In this embodiment, after the desulfurization waste water in the desulfurization waste water drain pipe was discharged, closed first solenoid valve, opened the second solenoid valve, made the clean water in the clean water supply pipeline rinse atomizing nozzle.

In this way, the atomizing nozzle can be washed by the cleaning water in the cleaning water supply pipe, thereby preventing the nozzle from being clogged by the crystallized salt.

Finally, it should be pointed out that: the above examples are only for illustrating the technical solutions of the present application, and are not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.