ABSTRACT

Title : Simultaneous removal of NOX and SO₂ from the flue gas: A low temperature ozone based process.

PI: Dr. Snigdha Khuntia

Funding Organization: Department of Science and Technology (DST) and Science and Engineering Research Board (SERB)

Duration: 3 years 

Summary:- Removal of NO X and SO 2 from flue gases has been a serious problem for the nation from the past decade. Selective catalytic reduction (SCR) is considered as the most effective method for removal of NOx and studied extensively. Simultaneous removal of SO 2 and NO X can be achieved by a combination of wet flue gas desulfurization (WFGD) and SCR. But the individual treatment strategy results in expensive investment and operating cost. To overcome these limitations, various new methods have been proposed such as wet scrubbing, adsorption, electron beam irradiation, corona discharge, dielectric barrier discharge, radio frequency discharge, and electrochemical-catalytic cells etc. Wet scrubbing process is performed under ambient temperature and it is highly adaptable to various flue gas loads. At the same time it results in high volume of liquid wastes and lower efficiency.

One of the simplest methods for simultaneous removal of NO X and SO 2 is the use of hydrogen peroxide to oxidize NO X and SO 2 to HNO 3 and H 2 SO 4 , respectively, followed by absorption in an acidic solution. To increase the removal efficiency of NO X and SO 2  hydroxyl radicals (OH•) generated from O 3 can be used. Therefore this work aims to enhance the in-situ generation of OH• radicals by using O 3 +H 2 O 2 , O 3 +UV or O 3 +catalyst. Thereafter the OH• radical will react with NO X and SO 2 simultaneously to form to HNO 3 and H 2 SO 4 , respectively. The manganese based catalysts are more suitable for the dissociation of ozone into OH•. Hence inaddition to the above, this work will be focused on developing some suitable Mn-catalyst for catalytic ozonation process.

Keywords: Funded Research