The Technology of Tail Gases Purifying in Nitric Acid Plants and Design of deN2O and deNOx Reactors—Review

Abstract

The tightening standards of nitrogen oxides emission from industrial plants encourage nitric acid producers to search for new efficient solutions to meet the stringent emission limits. Industrial practice and the patent literature show that the effectiveness of deNOx (SCR) and deN2O technology is affected not only by the type and shape of the catalyst, but also by the method of its installation in a heterogenous catalytic reactor. The article presents the background of the problem, related to the emission of nitrogen oxides from nitric acid plants, and describes the technology of the tail gases purified from NOx and N2O. It shows various aspects that should be considered in designing reactors for deNOx and deN2O processes in nitric acid plants. The advantages and disadvantages of different catalytic basket designs, their industrial application and the direction of their design development were also indicated.