CN220669432U - Zero-emission pollution-discharge and steam-discharge integrated recovery device - Google Patents

Abstract

A zero-emission sewage and steam integrated recovery device, including a regular sewage expansion vessel, one end of which is connected to the boiler sewage system, the other end of which is connected to the continuous sewage expansion vessel through a continuous sewage pipe, and the top surface of which is connected through a continuous steam pipe Deaerator; its bottom is connected to a water-to-water heat exchanger through a sewage pipe, and a first sewage pump is installed on the sewage pipe; the output end of the water-to-water heat exchanger is connected in series with a sewage pool and a second sewage pump, and the output of the second sewage pump The end is connected to the desulfurization system; the top surface of the deaerator is connected to the spray tank through the exhaust pipe, and the middle part of the deaerator and the spray tank are also connected through a first connecting pipe, and a condensate pump is installed on the first connecting pipe. ; The top surface of the regular sewage discharge expansion container is connected to the steam-water heat exchanger through a fixed discharge steam pipe, which is connected to the spray tank. The steam-water heat exchanger is connected to the water-water heat exchanger through the heat exchange pipe. The entire system is flexible and has strong applicability.

Description

Zero-emission sewage and steam integrated recovery device

Technical field

The utility model relates to the technical field of preheat recovery devices, in particular to a zero-emission sewage and steam exhaust integrated recovery device for boilers.

Background technique

The heat and working fluid losses in the thermal system of the power station mainly come from the regular blowdown of the boiler, continuous blowdown and deaerator exhaust steam loss. At present, both conventional boilers and waste heat boilers have regular blowdown expansion to generate secondary steam and deaerator exhaust. The steam is directly emptied, resulting in the "white dragon" phenomenon, which not only wastes the thermal energy of the steam, but also wastes valuable high-quality condensate. In addition, the temperature of the wastewater discharged from the regular sewage expansion container is relatively high, and industrial water needs to be blended. Cooling wastes water resources, and the wastewater has high alkalinity and is difficult to utilize. It needs to be discharged to sewage treatment equipment for treatment.

In order to solve this problem, various scientific research institutes and power plants are actively thinking. At present, some solutions have been mastered, and some power plants have been transformed and achieved some results. For example, the technology of cooling and condensing fixed-volume expansion steam or deaerator exhaust through water spraying, recycling the condensed water, and the technology of recovering the heat of the sewage discharged from the sewage expansion container through heat exchangers. However, the existing technologies focus on solving local problems and are not a complete set of recycling technologies. For example, the total alkalinity of the wastewater discharged from the regular sewage expansion container is 1.5 to 2 times that of the water supply, and the pH value is 10 to 12, which is alkaline. Wastewater only uses its heat, and the working fluid cannot be used. If the above-mentioned technologies are used respectively, there will be problems such as the recovery system is complex and inflexible, the waste heat is difficult to utilize, and the utilization rate is low. It has certain limitations and cannot optimize the system.

Therefore, there is an urgent need for a set of technologies that can simultaneously recover waste heat and working fluids from regular boiler blowdowns, continuous blowdowns and deaerator exhausts from an overall perspective, and achieve zero emissions.

Utility model content

In view of the shortcomings in the above-mentioned existing production technology, the applicant provides a reasonably structured zero-emission sewage and exhaust steam integrated recovery device, thereby making the entire system flexible and highly adaptable, while simultaneously recovering boiler sewage and exhaust steam in an integrated manner. Zero-emission recycling technology.

The technical solutions adopted by this utility model are as follows:

An integrated recovery device for zero-emission sewage and steam, which includes a regular sewage expansion container. One end of the middle part of the regular sewage expansion container is connected to the boiler sewage system. The other end of the middle part of the regular sewage expansion container is connected to the continuous sewage expansion container through a continuous sewage pipe. The top surface of the continuous sewage expansion container is connected to the deaerator through a continuous steam pipe; the bottom of the regular sewage expansion container is connected to the water-water heat exchanger through the sewage pipe. A first sewage pump is installed on the sewage pipe, and the regular sewage expansion container is connected to the third A branch pipe is provided in parallel on the sewage pipe between one sewage pump to maintain the liquid level inside the regular sewage expansion container; a sewage pool and a second sewage pump are connected in series to the output end of the water-to-water heat exchanger, and the second sewage pump is The output end of the sewage pump is connected to the desulfurization system;

The top surface of the deaerator is connected to the spray tank through the exhaust pipe, and the middle part of the deaerator and the spray tank are also connected through a first connecting pipe, and a condensate pump is installed on the first connecting pipe;

The top surface of the regular sewage expansion container is connected to a steam-water heat exchanger through a fixed discharge steam pipe, the steam-water heat exchanger is connected to the spray tank, and the steam-water heat exchanger is connected to the water-water heat exchanger through a heat exchange pipe;

The deaerator and the steam-water heat exchanger are connected through a second communication pipe, and the upper part of the spray tank is also connected to a first delivery pipe, and the first delivery pipe is connected to normal temperature desalted water.

As a further improvement of the above technical solution:

The water-to-water heat exchanger is connected to the first conveying pipe through a third connecting pipe. A second conveying pipe is branched on the third connecting pipe. The second conveying pipe conveys normal temperature softened water. A first conveying pipe is installed on the second conveying pipe. valve, a second valve is installed on the third communication pipe; a pipe connected to the heating system is branched on the second communication pipe, a third valve is installed on the pipe, and a fourth valve is installed on the second communication pipe. valve.

The installation positions of the first valve and the second valve correspond to each other.

The installation positions of the third valve and the fourth valve correspond to each other.

When using softened water in winter, the first valve opens, the second valve closes, the corresponding third valve opens, and the fourth valve closes.

When desalted water is used in summer, the first valve is closed and the second valve is opened. The corresponding third valve is closed and the fourth valve is opened.

The structures of the water-to-water heat exchanger and the steam-to-water heat exchanger are the same.

A baffle separator is provided inside the spray tank.

The beneficial effects of this utility model are as follows:

The utility model has a compact and reasonable structure and is easy to operate. Through the mutual cooperation between various components, it solves the problem of decentralized waste heat recovery technology, complex recovery system, inflexible system and difficult utilization of heat. The recovery boiler systematically discharges sewage regularly and continuously. The waste heat and condensate water from the sewage blowdown and deaerator exhaust can be used to heat softened water during the heating and cooling seasons and serve as a heat source for factory heating or cooling. In other seasons, the desalted water can be heated to increase the boiler water replenishment temperature, making the system more flexible. Adapting to the needs of more user loads can bring greater economic benefits.

At the same time, the utility model also has the following advantages:

(1) This utility model can not only recover the waste heat from the boiler's regular sewage blowdown, continuous sewage blowdown and deaerator exhaust, but also recover the precious working fluid - condensed water, and solve the problem of difficulty in utilizing the wastewater working fluid discharged from the regular sewage blowdown expansion vessel. , achieving zero emissions. It can not only recover energy and working fluids, but also solve the environmental pollution problem of boiler blowdown and exhaust steam being discharged into the atmosphere. It is suitable for various boiler systems, including: coal-fired boilers, gas-fired boilers, oil-fired boilers, etc. The system is flexible and practical. It has the characteristics of high waste heat recovery efficiency, energy saving and environmental protection.

(2) The use of a spray tank can not only recover the waste heat of the fixed-discharge secondary steam and deaerator exhaust, but also recover the condensed water, and can preliminarily deoxygenate the desalted water, reducing the corrosion of the deaerator desalted water supply pipe , enhance the deaeration effect of the deaerator.

(3) Use a water-to-water heat exchanger to heat softened water during the heating and cooling seasons as a heating and cooling heat source, and heat desalted water as boiler replenishment water in other seasons.

(4) The use of steam-water heat exchangers can not only solve the problem of environmental pollution by secondary steam from fixed discharge, but also recover waste heat and condensed water.

(5) The wastewater produced by the secondary expansion of the regular sewage expansion vessel is sent to the desulfurization system after settling in the sewage tank. The alkali in the wastewater reacts with the SO ₂ in the flue gas, saving the use of desulfurization alkaline agents.

Description of the drawings

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

Figure 2 is a partial view (1) of the utility model.

Figure 3 is a partial view (2) of the utility model.

Figure 4 is a partial view (3) of the utility model.

Among them: 1. Regular sewage expansion container; 2. Continuous sewage expansion container; 3. First sewage pump; 4. Deaerator; 5. Water-to-water heat exchanger; 6. Steam-to-water heat exchanger; 7. Spray tank; 8. Condensate pump; 9. Sewage tank; 10. Second sewage pump; 11. Second valve; 12. First valve; 13. Third valve; 14. Fourth valve; 15. Fixed steam pipe; 16. Continuous steam pipe; 17. Continuous sewage pipe; 18. Branch pipe; 19. Second connecting pipe; 20. Exhaust pipe; 21. First connecting pipe; 22. Heat exchange pipe; 23. First conveying pipe; 24 , the third connecting pipe; 25. the second conveying pipe; 26. the sewage pipe.

Detailed ways

The specific implementation manner of the present utility model will be described below in conjunction with the accompanying drawings.

As shown in Figures 1 to 4, the zero-emission sewage and steam integrated recovery device of this embodiment includes a regular sewage expansion vessel 1. The middle end of the regular sewage expansion vessel 1 is connected to the boiler sewage system. The regular sewage expansion vessel 1 has The other end of the middle part is connected to the continuous sewage expansion container 2 through the continuous sewage pipe 17. The top surface of the continuous sewage expansion container 2 is connected to the deaerator 4 through the continuous steam pipe 16; the bottom of the regular sewage expansion container 1 is connected to the water-water exchanger through the sewage pipe 26. Heater 5, a first sewage pump 3 is installed on the sewage pipe 26. A branch pipe 18 is provided in parallel on the sewage pipe 26 between the regular sewage expansion container 1 and the first sewage pump 3 to maintain the internal flow of the regular sewage expansion container 1. Liquid level; the output end of the water-to-water heat exchanger 5 is connected in series with a sewage pool 9 and a second sewage pump 10, and the output end of the second sewage pump 10 is connected to the desulfurization system;

The top surface of the deaerator 4 is connected to the spray tank 7 through the exhaust pipe 20. At the same time, the middle part of the deaerator 4 and the spray tank 7 are also connected through a first communication pipe 21. A condensation water pump is installed on the first communication pipe 21. 8;

The top surface of the regular sewage expansion container 1 is connected to the steam-water heat exchanger 6 through the fixed discharge steam pipe 15. The steam-water heat exchanger 6 is connected to the spray tank 7. The steam-water heat exchanger 6 is connected to the water-water heat exchanger 5 through the heat exchange pipe 22. connect;

The deaerator 4 and the steam-water heat exchanger 6 are connected through a second communication pipe 19. The upper part of the spray tank 7 is also connected to a first delivery pipe 23. The first delivery pipe 23 is connected to normal temperature desalted water.

The water-to-water heat exchanger 5 is connected to the first delivery pipe 23 through a third communication pipe 24. A second delivery pipe 25 is branched from the third communication pipe 24. The second delivery pipe 25 carries normal temperature softened water. The second delivery pipe 25 A first valve 12 is installed on the top, and a second valve 11 is installed on the third communication pipe 24; a branch of the second communication pipe 19 is connected to the heating system, and a third valve 13 is installed on the pipe. A fourth valve 14 is installed on the pipe 19 .

The installation positions of the first valve 12 and the second valve 11 correspond to each other.

The installation positions of the third valve 13 and the fourth valve 14 correspond to each other.

When using demineralized water in winter, the first valve 12 is opened, the second valve 11 is closed, the corresponding third valve 13 is opened, and the fourth valve 14 is closed.

When desalted water is used in summer, the first valve 12 is closed, the second valve 11 is opened, the corresponding third valve 13 is closed, and the fourth valve 14 is opened.

The water-to-water heat exchanger 5 and the steam-to-water heat exchanger 6 have the same structure.

A baffle separator is provided inside the spray tank 7 .

This recovery technology recovers waste heat from the boiler's regular sewage blowdown, continuous sewage blowdown and deaerator 4, and recovers valuable industrial condensate and wastewater discharged from the regular sewage blowdown expansion vessel 1.

The main equipment used is: a regular sewage expansion vessel 1, a continuous sewage expansion vessel 2, a spray tank 7, a condensate pump 8, two sewage pumps, a water-to-water heat exchanger 5, a Taiwan steam-water heat exchanger 6.

The boiler regularly blows down sewage to the regular sewage expansion vessel 1, the boiler continuously blows down the sewage to the continuous sewage expansion vessel 2, the secondary steam from the continuous sewage expansion vessel 2 is sent to the deaerator 4 as deaerator 4, and the continuous sewage expansion vessel 2 discharges The sewage is discharged to the regular sewage expansion tank 1 for continued capacity expansion.

Cold water (softened water or demineralized water) first exchanges heat with the sewage in the regular sewage expansion container 1 in the water-to-water heat exchanger 5 to reduce the temperature of the sewage. In particular, the heat of the sewage is recovered and the industrial water for mixing and cooling is saved. , because the water-to-water heat exchanger 5 increases the resistance, a first sewage pump 3 is added to the pipeline. The cooled sewage is discharged to the sewage pool 9 for sedimentation, and is then pressurized by the second sewage pump 10 before being sent to Desulfurization system, because the alkalinity in sewage is mainly sodium hydroxide alkalinity and carbonate alkalinity, it can absorb SO ₂ in the flue gas and react to desulfurize, so it can save desulfurization alkaline agents. The heat-exchanged cold water is sent to the steam-water heat exchanger 6 for secondary steam heat exchange with the regular sewage expansion vessel 1 to condense the steam. The heated hot water is supplied externally, and the condensed water is sent to the spray tank 7 . The exhaust steam from the deaerator 4 is discharged to the spray tank 7, where it is sprayed and condensed by the normal temperature demineralized water. The recovered water in the spray tank 7 is pumped through the condensate pump 8 to the deaerator 4 for water replenishment. A barrier is set inside the spray tank 7. The plate separator can separate gas and liquid, and the non-condensable gas will be evacuated after separation.

In the heating and cooling seasons, softened water is used as the heating or cooling heat source in the factory. In other seasons, desalted water is used to increase the boiler replenishing temperature. The heated desalted water is sent to the deaerator 4 to replenish water, thereby reducing the energy consumption of the factory. It is suitable for boiler thermal systems with various parameters such as medium, medium and low. It has strong practicability, high waste heat recovery efficiency and good economic benefits.

As shown in Figure 1, the operation process of the entire system is as follows:

First: the boiler regularly blows down sewage to the regular sewage expansion vessel 1, and the boiler continuously blows down sewage to the continuous sewage expansion vessel 2. After flashing in the continuous sewage expansion vessel 2, a saturated steam of about 0.2MPa is generated and sent to the deaerator 4 as a deaerator. Oxygen steam, the wastewater from the continuous sewage expansion container 2 is discharged to the regular sewage expansion container 1 for continued expansion.

Then: the regular sewage expansion container 1 generates saturated steam of about 110°C, which is sent to the steam-water heat exchanger 6. The sewage discharged from the regular sewage expansion container 1 is sent to the water-water heat exchanger 5 by the first sewage pump 3, and the sewage is recovered heat, and saves the industrial water for mixing and cooling. After the heat exchange, the sewage of about 35 degrees is settled in the sewage pool 9, and then pressurized by the second sewage pump 10 and sent to the desulfurization system. The alkali and flue gas in the sewage SO ₂ reaction, thereby saving desulfurization alkaline agents.

Next: cold water (softened water or demineralized water) first exchanges heat in the water-water heat exchanger 5. The heat-exchanged cold water is then sent to the steam-water heat exchanger 6 to exchange heat with the regular sewage expansion vessel 1 to condense the steam and heat it up. The hot water (60-70 degrees) is used for external heating in winter, and is sent to the deaerator 4 for replenishment in summer, reducing the consumption of deaerator steam, thus improving thermal efficiency and reducing energy consumption.

Finally: the condensed water generated by the steam-water heat exchanger 6 is sent to the spray tank 7, and the exhaust steam of the deaerator 4 is also discharged to the spray tank 7, where it is sprayed and condensed through normal temperature desalted water, and the water recovered in the spray tank 7 is condensed The water pump 8 supplies water to the deaerator 4. A baffle separator is provided inside the spray tank 7 to separate gas and liquid. After separation, the non-condensable gas is emptied.

Whether to use softened water or demineralized water for cold water is switched through a valve. When using softened water in winter, the first valve 12 is opened, the second valve 11 is closed, the corresponding third valve 13 is opened, and the fourth valve 14 is closed. In summer, on the contrary, the first valve 12 is closed, the second valve 11 is opened, the corresponding third valve 13 is closed, and the fourth valve 14 is opened.

After the integrated zero-emission recovery technology of the utility model's boiler thermal system sewage and exhaust steam waste heat is put into use, after the boiler sewage and exhaust steam are processed through the above system process, all the sewage exhaust and exhaust steam waste heat are recovered, and the valuable condensation waste is recovered The water quality is improved, and the problem that the wastewater discharged from the regular sewage expansion vessel 1 cannot be used is solved, zero discharge is achieved, the waste heat recovery efficiency is improved, and it has great economic and environmental benefits.

The above description is an explanation of the utility model, not a limitation of the utility model. Please refer to the claims for the limited scope of the utility model. Any modification can be made within the protection scope of the utility model.

Claims (8)

1. A zero-emission sewage and steam integrated recovery device, characterized by: including a regular sewage expansion container (1), the middle end of the regular sewage expansion container (1) is connected to the boiler sewage system, and the regular sewage expansion container (1) The other end of the middle part is connected to the continuous sewage expansion container (2) through a continuous sewage pipe (17), and the top surface of the continuous sewage expansion container (2) is connected to the deaerator (4) through a continuous steam pipe (16); the regular sewage discharge The bottom of the expansion container (1) is connected to the water-to-water heat exchanger (5) through a sewage pipe (26). A first sewage pump (3) is installed on the sewage pipe (26). The expansion container (1) and the first sewage pump are regularly discharged. A branch pipe (18) is provided in parallel on the sewage pipe (26) between the pumps (3) to maintain the liquid level inside the regular sewage expansion container (1); the output end of the water-to-water heat exchanger (5) is connected in series There is a sewage pool (9) and a second sewage pump (10), and the output end of the second sewage pump (10) is connected to the desulfurization system; The top surface of the deaerator (4) is connected to the spray tank (7) through the exhaust pipe (20). At the same time, the middle part of the deaerator (4) and the spray tank (7) are also connected through a first connecting pipe (21). ) is connected, and a condensate pump (8) is installed on the first communication pipe (21); The top surface of the regular sewage expansion container (1) is connected to a steam-water heat exchanger (6) through a fixed discharge steam pipe (15), and the steam-water heat exchanger (6) is connected to a spray tank (7). The heat exchanger (6) is connected to the water-to-water heat exchanger (5) through the heat exchange tube (22); The deaerator (4) and the steam-water heat exchanger (6) are connected through a second communication pipe (19), and a first delivery pipe (23) is also connected to the upper part of the spray tank (7). The first delivery pipe (23) is connected to normal temperature desalted water. 2. The zero-emission sewage and steam integrated recovery device according to claim 1, characterized in that: the water-to-water heat exchanger (5) is connected to the first delivery pipe (23) through a third connecting pipe (24) , there is a second conveying pipe (25) branched on the third connecting pipe (24), the second conveying pipe (25) conveys normal temperature softened water, and the first valve (12) is installed on the second conveying pipe (25), so A second valve (11) is installed on the third communication pipe (24); a branch of the second communication pipe (19) is connected to the heating system, and a third valve (13) is installed on the pipe. A fourth valve (14) is installed on the second communication pipe (19). 3. The zero-emission sewage and steam integrated recovery device according to claim 2, characterized in that the installation positions of the first valve (12) and the second valve (11) correspond to each other. 4. The zero-emission sewage and steam integrated recovery device according to claim 2, characterized in that the installation positions of the third valve (13) and the fourth valve (14) correspond to each other. 5. The zero-emission sewage and exhaust steam integrated recovery device as claimed in claim 2, characterized in that: using softened water in winter, the first valve (12) is opened, the second valve (11) is closed, and the corresponding third valve ( 13) is opened and the fourth valve (14) is closed. 6. The zero-emission sewage and steam integrated recovery device as claimed in claim 2, characterized in that: desalted water is used in summer, the first valve (12) is closed, the second valve (11) is opened, and the corresponding third valve ( 13) is closed and the fourth valve (14) is opened. 7. The zero-emission sewage and exhaust steam integrated recovery device according to claim 1, characterized in that the water-to-water heat exchanger (5) and the steam-to-water heat exchanger (6) have the same structure. 8. The zero-emission exhaust and steam integrated recovery device according to claim 1, characterized in that a baffle separator is provided inside the spray tank (7).