Dedusting and demisting device of spiral flow plate

Abstract

The invention discloses a dedusting and demisting device of a spiral flow plate. The dedusting and demisting device comprises a plurality of dedusting and demisting units, wherein each dedusting and demisting unit comprises a hollow overflowing barrel body, a spiral flow cyclone is arranged in the overflowing barrel body, a flue gas guiding device is connected to the lower part of the spiral flow cyclone, the flue gas guiding device is fixedly connected with the overflowing barrel body, a blowing hole is formed in the flue gas guiding device, and a discharge hole is formed in the inner wall of the overflowing barrel body; the flue gas guiding device is a variable cross-section truncated cone-shaped hollow barrel body of which the cross-sectional area changes continuously, and the upper end surface of the truncated cone-shaped hollow barrel body is connected with the spiral flow cyclone. By using the flue gas guiding device, continuous change of the airflow moving state is realized, the stability of a formed liquid film is good, and secondary entrainment of liquid drops is effectively prevented. Compared with a dedusting and demisting device without the guiding device, the gas distribution state is more uniform, and local disturbance of airflow which passes through the spiral flow cyclone is effectively reduced, so that the airflow moving state is more stable, and the stability of the formed liquid film is better.

Description

technical field [0001] The invention belongs to the field of flue gas purification equipment, and in particular relates to a swirl plate dust and mist removal device. Background technique [0002] At present, the wet flue gas after limestone wet desulfurization carries more insoluble gypsum and limestone particles in the second time, and the droplet concentration at the outlet of the conventional demister is 75mg / Nm 3 , coupled with the unremoved smoke and dust in the flue gas, the smoke and dust concentration in the flue gas at the outlet of the desulfurization tower cannot meet the current environmental protection regulations, and the smoke and dust emission concentration of coal-fired units in key areas should not be higher than 20mg / m 3 requirements, and cannot meet the current regulations on ultra-clean emissions for smoke content ≤ 5mg / Nm 3 requirements. [0003] At present, most of the existing large-scale coal-fired units in China adopt the limestone-gypsum desulfu...

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Problems solved by technology

[0002] At present, the wet flue gas after limestone wet desulfurization carries more insoluble gypsum and limestone particles in the second time, and the droplet concentration at the outlet of the conventional demister is 75mg / Nm 3 , coupled with the unremoved smoke and dust in the flue gas, the smoke and dust concentration in the flue gas at the outlet of the desulfurization tower cannot meet the current environmental protection regulations, and the smoke and dust emission concentration of coal-fired units in key areas should not be higher than 20mg / m 3 requirements, and cannot meet the current regulations on ultra-clean emissions for smoke content ≤ 5mg / Nm 3 requirements

[0003] At present, most of the existing large-scale coal-fired units in China adopt the limestone-gypsum desulfurization process. The dust and fog removal process route of wet desulfurization and clean flue gas that is often used at present is "mist eliminator + wet electrostatic". Using this process route, it can reach The dust content of the flue gas at the outlet of the desulfurization tower is less than or equal to 5mg / Nm 3 However, the wet electrostatic precipitator is expensive, consumes a lot of power, and is complicated to operate and maintain.

When the main body is arranged separately, it is independent of the wet desulfurization tower body, and a certain site needs to be provided on site. Therefore, for power plants with limited space or compact layout, installation, layout, and maintenance are more difficult.

[0004] Chinese patent CN 204208428U discloses a deep dedusting and demisting device, in which there is no flue gas guide device in front of the swirler, so that when the flue gas flow passes through the secondary swirl, the flow field is prone to sudden changes and the flow state changes Inhomogeneity, it is easy to affect the stability of the formed liquid film, and it is easy to cause secondary entrainment of droplets, which in turn affects the effect of dust removal and fog removal

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