Low Temperature Performance of Selective Catalytic Reduction of NO with NH3 under a Concentrated CO2 Atmosphere

Abstract

Selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) has been widely investigated to reduce NO x emissions from combustion processes, which cause environmental challenges. However, most of the current work on NO x reduction has focused on using feed gas without CO 2 or containing small amounts of CO 2 . In the future, oxy-fuel combustion will play an important role for power generation, and this process generates high concentrations of CO 2 in flue gas. Therefore, studies on the SCR process under concentrated CO 2 atmosphere conditions are important for future SCR deployment in oxy-fuel combustion processes. In this work, Mn-and Ce-based catalysts using activated carbon as support were used to investigate the effect of CO 2 on NO conversion. A N 2 atmosphere was used for comparison. Different process conditions such as temperature, SO 2 concentration, H 2 O content in the feed gas and space velocity were studied. Under Mn-Ce/AC conditions, the results suggested that Mn metal could reduce the inhibition effect of CO 2 on the NO conversion, while Ce metal increased the inhibition effect of CO 2 . High space velocity also resulted in a reduction of CO 2 inhibition on the NO conversion, although the overall performance of SCR was greatly reduced at high space velocity. Future investigations to design novel Mn-based catalysts are suggested to enhance the SCR performance under concentrated CO 2 atmosphere conditions.

The Potential of Activated Carbon Made of Agro-Industrial Residues in NOx Immissions Abatement

“…Among the various harmful gases, nitrogen oxides (NO x ) have a negative impact through the smog and acid rain formations as well as the decrease of the superior ozone layer [1,2]. Several methods have been applied for nitrogen oxides elimination including the reduction of NO x by selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) [3]. However, these techniques have several drawbacks such as costs and technical complexity.…”

Techno-Economic Analysis of a 600 MW Oxy-Enrich Pulverized Coal-Fired Boiler

“…Tremendous quantities of CO 2 are produced from fossil fuel combustion every year. Among CO 2 -capturing technologies, oxy-fuel combustion is one of the most promising technologies [4][5][6][7]. However, compared with air combustion, extra energy is required (e.g., ASU (air separation unit) etc.)…”

Low Temperature Selective Catalytic Reduction Using Molding Catalysts Mn-Ce/FA and Mn-Ce/FA-30%TiO2

“…Our previous work studied Mn-and Ce-based catalysts using activated carbon as support for low temperature SCR [11]. Fly ash (FA), which is much cheaper than activated carbon, is a solid waste collected and discharged by thermal power plant [12], which is generally alkaline and mainly consists of SiO 2 , Al 2 O 3 and Fe 2 O 3 .…”