US, China and many other industrialized economies rely heavily on coal for electricity generation. Unfortunately coal has become a controversial fuel due to various pollutants and carbon dioxide (CO2) generated during combustion. Regulated pollutants include nitrogen oxides (NOx) and sulfur oxides (SOx) which react with the water vapor in the atmosphere to form acid rain. CO2 also reacts with water molecules to form carbonic acid, which gives rise to ocean acidification. This research takes advantage of the acidification tendency of the gaseous pollutants to reduce them. Pollutant molecules in the flue gas are encouraged to combine with water vapor to form droplets of oxyacids which are then separated before the flue gas is discharged into the air. The proposed cleaning process is as follows: Given a flue gas generated by burning coal, a charging device provides electrons to those molecules which have positive electron affinity. Such molecules include NO2, SOx (x=1-3) and HgO. Ions are allowed to float through the flue gas so that they can electrically attract other pollutants and water molecules to form droplets. Charged droplets are separated from the rest of the flue gas using electric and/or magnetic fields.
Journal: TechConnect Briefs
Volume: 3, Nanotechnology 2012: Bio Sensors, Instruments, Medical, Environment and Energy (Volume 3)
Published: June 18, 2012
Pages: 753 - 756
Industry sector: Energy & Sustainability
Topic: Materials for Oil & Gas