Power plant condensate flue gas whitening

Power plant condensate flue gas whitening

Whitening technology refers to the modification of the slurry circulation pipeline. Generally, slurry heat exchangers are installed on the spray pipelines of the upper or higher floors and the second highest floor. The cooled slurry is used to reduce the exhaust temperature of the absorption tower, thereby reducing the evaporation water volume of the desulfurization tower. Cooling water (seawater) is used to cool the slurry through a slurry heat exchanger, and then the cold slurry sprayed into the absorption tower is used to cool the flue gas inside the absorption tower, thereby reducing the net flue gas temperature and humidity at the outlet of the absorption tower, achieving the effect of cooling, condensation, and whitening. After the flue gas is cooled, the condensed water falls back into the absorption tower, and the water balance inside the tower is finally considered.

After desulfurization, defogging, and dust removal, the temperature of the condensed flue gas drops to 50 ℃. At this moment, the flue gas is usually full and wet, requiring a full heat pipe heat exchanger to heat it up again to above 85 ℃ and convert it into steam. The steam rises to the heat release section under the effect of pressure difference; Under the cooling effect of the clean flue gas outside the pipe, steam condenses and releases latent heat of vaporization outward. The clean flue gas obtains heat, and the condensate returns to the heating section by gravity. This cycle repeats, and the heat of the original flue gas is transferred to the clean flue gas, heating it and achieving the effect of flue gas whitening.

Power plant condensate flue gas whitening

Due to the initial stage of flue gas whitening, there are different understandings of why flue gas whitening occurs. My opinion is that achieving year-round white smoke exhaust is a minimum requirement, which can solve visual pollution and reassure the general public; Can reduce the impact on flight and highway transportation; At the same time, there should be at least four additional functions:

① Beneficial for eliminating haze;

② Water conservation;

③ Energy saving;

④ Wastewater treatment;

Although there are different opinions in the industry on whether flue gas whitening can contribute to haze removal, its effectiveness in defogging, water conservation, and energy conservation has been preliminarily validated. The following will explore it separately.