CN204829982U - Flue gas degree of depth cooling device - Google Patents

Abstract

The utility model relates to a flue gas degree of depth cooling device, including the boiler air heater is connected to the afterbody flue of boiler, the cold ware of high temperature level cigarette is connected to air heater's one end, the forced draught blower is connected to air heater's the other end, the cold ware of high temperature level cigarette passes through electrostatic precipitator and connects the draught fan, horizontal gas pass behind the draught fan is connected with the cold ware of low temperature level cigarette, the cold ware of low temperature level cigarette is connected with the desulfurizing tower, the desulfurizing tower is connected with the chimney. The beneficial effects of the utility model are that: exhaust gas temperature's cooling range has been increased to reduce the coal consumption, brought fine environmental benefit and considerable economic benefits, the service life of flue gas cryrogenic equipment is prolonged, the efficiency of electrostatic precipitator is improved, the water that reduces desulfurization system consumes.

Description

A flue gas deep cooling device

technical field

The utility model relates to a flue gas deep cooling device in the field of power generation, in particular to a flue gas cooling device that avoids low-temperature corrosion of metal materials and uses high-temperature metal materials, has high cost performance, can greatly reduce the exhaust gas temperature, and effectively achieve energy saving and emission reduction. Air deep cooling unit.

Background technique

The use of flue gas deep cooling technology is a new technology that has gradually emerged in the power generation industry in recent years for energy saving and emission reduction. The flue gas deep cooling efficiency enhancement and emission reduction technology is to reduce the exhaust gas temperature of the boiler from about 125°C to 150°C to the optimum temperature suitable for desulfurization. At present, most of the materials of domestic flue gas deep coolers are made of metal materials. However, since sulfur and other elements in metal fuels produce SO ₂ , HCl, HF, etc. during the combustion process, when the flue gas containing SO ₂ enters the flue, part of the SO ₂ will be converted into SO ₃ and combined with the flue gas The water vapor in the gas is combined to generate H ₂ SO ₄ steam, which condenses on the internal surface of the equipment to form a mixture of sulfuric acid, hydrochloric acid, hydrofluoric acid, etc., reacts with alkaline ash, and also reacts with metals to cause corrosion. The condensed mixed acid not only corrodes the metal pipes, but also adheres to the fly ash in the flue gas, and the formed mixture hardens, thereby aggravating the ash accumulation and ash blocking inside the equipment. At the same time, corrosion will cause damage and water leakage, which will further reduce the flue gas temperature and further intensify the corrosion, resulting in a vicious circle, shortening the service life of the equipment, and seriously affecting the long-term safe and stable operation of the device. Most domestic applications reduce the temperature of the flue gas to about 100°C, so the waste heat of the flue gas cannot be fully utilized. Many foreign power plants use acid-resistant fluoroplastics (Fluoropolymer) to make flue gas deep coolers to solve the problem of low-temperature corrosion in order to fully reduce the exhaust gas temperature. However, due to imported materials, the price is relatively expensive and the cost performance is not high.

Utility model content

In view of the deficiencies in the above problems, the utility model provides a flue gas that avoids the low-temperature corrosion of metal materials and the combined use of high-temperature metal materials, is cost-effective, can greatly reduce the exhaust gas temperature, and effectively achieve energy saving and emission reduction. Deep cooling unit.

In order to achieve the above purpose, the utility model provides a flue gas deep cooling device, which includes a boiler, an air preheater is connected to the tail flue of the boiler, and one end of the air preheater is connected to a high-temperature grade smoke cooler. The other end of the air preheater is connected to the air blower, the high-temperature level smoke cooler is connected to the induced draft fan through the electrostatic precipitator, the horizontal flue behind the induced draft fan is connected to the low-temperature level smoke cooler, and the low-temperature level smoke cooler It is connected with the desulfurization tower, and the desulfurization tower is connected with the chimney.

As a further improvement of the utility model, a first heat exchanger is arranged inside the high-temperature stage fume cooler.

As a further improvement of the utility model, a second heat exchanger is arranged in the low-temperature stage fume cooler.

As preferred in the present invention, the first heat exchanger is a plate heat exchanger.

As preferred in the present invention, the second heat exchanger is a plate heat exchanger.

The beneficial effects of the utility model are:

1. Increase the cooling range of exhaust gas temperature, thereby reducing coal consumption, bringing good environmental benefits and considerable economic benefits.

2. Improve the service life of flue gas cryogenic equipment.

3. Improve the efficiency of the electrostatic precipitator.

4. Reduce the water consumption of the desulfurization system.

Description of drawings

Fig. 1 is a structural schematic diagram of a flue gas deep cooling device of the present invention.

In the figure: 1. Boiler; 2. Air preheater; 3. High temperature level smoke cooler; 4. Electrostatic precipitator; 5. Induced draft fan; 6. Blower fan; 7. Low temperature level smoke cooler; 9. Chimney.

Detailed ways

As shown in Figure 1, a flue gas deep cooling device described in the embodiment of the utility model includes a boiler 1, an air preheater 2 is connected to the tail flue of the boiler 1, and one end of the air preheater 2 is connected to a high temperature stage The smoke cooler 3, the other end of the air preheater 2 is connected to the air blower 6, the high temperature level smoke cooler 3 is connected to the induced draft fan 5 through the electrostatic precipitator 4, and the horizontal flue behind the induced draft fan 5 is connected to the low temperature level smoke cooler 7, The low temperature level smoke cooler 7 is connected with the desulfurization tower 8 , and the desulfurization tower 8 is connected with the chimney 9 .

Wherein, a first heat exchanger is arranged in the high-temperature stage fume cooler 3 , and a second heat exchanger is arranged in the low-temperature stage fume cooler 7 . Both the first heat exchanger and the second heat exchanger are plate heat exchangers.

The flue gas cooler of the utility model is arranged in two stages. The high temperature level fume cooler 3 is made of metal material and arranged in front of the electrostatic precipitator 4 to reduce the temperature of the flue gas to 110-120°C. The low temperature level fume cooler 7 is made of fluorine The plastic is made and arranged behind the electrostatic precipitator 4 and the induced draft fan 5 to reduce the temperature of the smoke from 110-120°C to 85-95°C. This arrangement of grades and materials can avoid the low-temperature corrosion problem of metal materials because the high-temperature grade is reduced to 110-120°C, and the low-temperature grade is made of fluoroplastic material, which can reduce the smoke temperature to 85-95°C, which can greatly reduce the smoke temperature. Reduce the flue gas temperature, greatly utilize the waste heat of the flue gas, improve the economy of the unit, and effectively achieve energy saving and emission reduction.

Specific use: when running in summer, heat the condensate water of the steam turbine, take water from the low feed inlet, return the water to the low feed outlet; install a plate heat exchanger to heat the water in the heating network to ensure the quality of the boiler feed water in winter operation, and take the water from the heating network back to the boiler. The water is used as the inlet water of the plate heat exchanger, and the outlet water directly enters the heating network for water supply.

The above descriptions are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (5)

1. A flue gas deep cooling device, characterized in that it comprises a boiler (1), the tail flue of the boiler (1) is connected to an air preheater (2), and the air preheater (2) One end is connected to a high-temperature level smoke cooler (3), the other end of the air preheater (2) is connected to a blower (6), and the high-temperature level smoke cooler (3) is connected to an induced draft fan ( 5), the horizontal flue behind the induced draft fan (5) is connected with the low temperature level smoke cooler (7), and the low temperature level smoke cooler (7) is connected with the desulfurization tower (8), and the desulfurization tower (8 ) is connected with the chimney (9). 2. The flue gas deep cooling device according to claim 1, characterized in that, a first heat exchanger is arranged inside the high-temperature level smoke cooler (3). 3. The flue gas deep cooling device according to claim 1, characterized in that, a second heat exchanger is arranged in the low-temperature stage smoke cooler (7). 4. The flue gas deep cooling device according to claim 2, characterized in that, the first heat exchanger is a plate heat exchanger. 5. The flue gas deep cooling device according to claim 3, characterized in that, the second heat exchanger is a plate heat exchanger.