2results about How to "Reduce nitrogen oxide emissions" patented technology

A burner (12) using the oxygen present in the descending flow (18) of gases, composed by a mixture of air with combustion products that circulates through the iron ore pelletizing furnace zones. The burner set (12) includes a fuel collector ring (24) equipped with fins (26) mounted on the inner part of the collector and further counts on a plurality of openings (30) for discharge of fuel gas. Said openings (30) make up a sequence of groups (32) aligned with each fin (26). The burner set (12) is inserted through the special window (16) and installed where the descending flow (18) needs to be heated, for example, from 850 to 1350°C. The fins (26) deflect part of the descending flow (18) and create the rotating effect in the gases in the furnace downcomer. The fuel gas jets discharged from the collector ring (24) are mixed with the flow of gases and burn in the descending flow current in a swirl. The even distribution of the fuel gas around the perimeter of the descending passage together with the descending flow swirling effect allows the quick mixing of the fuel gas with the descending oxygen flow and for this reason significantly reduces the NOx formation in the combustion zone.

The application discloses a nitric acid preparation system and method, and relates to the technical field of chemical industry, and can reduce tail gas emission and nitrogen oxide content in the tail gas during nitric acid preparation.