Eco-structure for building emission reduction

Strategy – FGD system – industry and power stations

FGD systems located in the extraction pipes and typically employ various techniques to capture and remove SO2 from flue gases. One of the most commonly used methods is wet scrubbing, which involves passing the flue gas through an absorber tower or chamber where it comes into contact with a liquid sorbent, usually a slurry of limestone or lime. The interaction between the flue gas and the sorbent facilitates chemical reactions that convert the SO2 into a less harmful compound, such as calcium sulfate or calcium sulfite.

The key steps in the wet scrubbing process of an FGD system are as follows:

1.Absorption: Flue gas enters the absorber tower and encounters the alkaline sorbent. The SO2 in the flue gas reacts with the sorbent to form sulfite or sulfate compounds.

2.Reaction and Neutralization: The sorbent, now containing the captured SO2, undergoes chemical reactions to convert the SO2 into stable compounds. This process often involves oxidation and neutralization reactions to ensure effective removal and stabilization of the sulfur compounds.

3.Separation and Solid/Liquid Handling: The treated flue gas, with reduced SO2 content, exits the absorber tower. The spent sorbent, now laden with captured pollutants, is separated from the flue gas and processed for further treatment or disposal. This step may involve solid-liquid separation, dewatering, and subsequent handling of the generated waste products.

4.Byproduct Utilization or Disposal: Depending on the specific FGD system and regulations, the byproducts generated during the FGD process, such as gypsum (calcium sulfate), can be further processed and utilized for various applications, such as construction materials or agricultural amendments. Alternatively, appropriate disposal methods may be employed for these byproducts.

(Cordoba, 2015)

Status of Flue Gas Desulphurisation (FGD) systems from coal-fired power plants

Eco-structure for building emission reduction

Strategy

FGD system = Purify Sulphur Dioxide wet scrubbing process

CO &PM 10, 2.5

Carbon Monoxide

O2 Oxygen

FGD system = Purify carbon monoxide & PM 10, 2.5 of building heating system through photosynthesis