There are several methods for flue gas whitening, including the following:

1. Low power consumption ion beam flue gas whitening: This method uses high-speed electrons to collide with flue gas, producing a large number of positive and negative ions. These ions condense with aerosols, saturated water droplets, and small particles in the flue gas, forming large particles that fall to the bottom of the dust collector under gravity, are discharged with the water flow, and finally flow into the desulfurization tower or wastewater collection tank, achieving the goal of reducing particles, aerosols, and water. This method is energy-saving and saves 1/10 of electricity consumption compared to traditional wet electric whitening when dealing with the same air volume.

2. Condensation phase change flue gas whitening: After wet desulfurization, the flue gas enters the heat exchange and defogging module, and dry air enters from the side and heats up, with the moisture content remaining unchanged and the relative humidity decreasing. After cooling, the moisture content of the smoke decreases, and liquid droplets precipitate, ultimately reaching an unsaturated state to avoid the production of white smoke or mist clusters. This method is not only efficient, energy-saving, water-saving and emission reducing, but also has a whitening efficiency of up to 99%, and can fully utilize waste heat.

3. Condensed mixed air flue gas whitening: The flue gas is removed of a large amount of moisture and condensed through a spray tower, and then enters a heat exchanger to exchange heat with air. The condensed water releases heat energy, causing the air temperature to rise. The heated dry air is introduced into the chimney end and mixed with the cooled and dehydrated flue gas, greatly reducing its relative humidity and dew point temperature. After being discharged, it will not reach the dew point temperature in a short period of time, and the moisture will not condense into mist.

4. New type of flue gas whitening device: This equipment uses natural air cooling and heat exchange to condense and precipitate an appropriate amount of moisture in the original flue gas. After passing through the heat exchanger, the temperature of the natural air rises and blends with the flue gas, making the flue gas dry and clean. The relative humidity decreases, and the temperature after discharge is lower than the dew point temperature. Moisture will not condense into water mist again, thus achieving the effect of visually not seeing white smoke.

These methods each have their own advantages and disadvantages, and choosing the appropriate method depends on the specific situation and needs.