Formation of Nitrogen Mono Oxide (NO) during Iron Ore Sintering Process

Surface Structures of CaFe₂O₄ (001), (100), (110) and (111): A Density Functional Theory Study

“…Moreover, the reduction behavior of calcium ferrite minerals under CO and H 2 were also investigated. [7][8][9][10][11][12] In addition, in recent research, it has been widely applied including as a thermal catalyst for decreasing the NOx emission in the sintering process, [13][14][15] as a photocatalytic for degradation of the organic wastewater 16,17) and volatile organic compounds, [18][19][20] as a photocathode for producing hydrogen in water splitting, [21][22][23] as a oxygen carrier for chemical looping gasification applications, [24][25][26][27][28] as a anode material for lithiumion batteries 29) and as a visible light activated gas sensor. 30) The surface structure of calcium ferrite affects the strength of sinter and reduction reaction of it with CO and H 2 in the blast furnace.…”

Mechanism of NOx Formation from Nitrogen in the Combustion of the Coals Used in Sintering Process

“…[4,5] After the ignition of the sintering process, coal/coke particles are exposed to a combustion atmosphere, where N present in the fuel reacts with O 2 to form NO x (98 pct represented by NO). [6] NO x formed in the sintering process is called fuel-NO x since it is generated from the burning fuel-N present in coal/coke. In addition, there are two possible ways to form NO x : thermal-NO x by the reaction between N 2 and O 2 gases present in the air and prompt NO x in terms of the decomposition of nitrogen compounds in the combustion zone.…”

“…[9,10,13,16] Iron ore sintering process represents more than 40 pct of the total NO x emissions from steel industries, which accounts for more than 10 pct of the total NO x emission among all kinds of industry. [3,6,12,14,[17][18][19][20][21] Nowadays, steelmaking companies are facing bigger challenges for environmental protection due to change in gas emission regulation, especially in NO x case. [7,13,18,19] As an example, South Korea and China determined to reduce NO x emission by national law.…”

“…[10][11][12]14] The previous studies have shown that sintering parameters such as temperature, oxygen content, heating rate, fuel type and additional materials had a notable influence on the nitrogen conversion ratio to NO x which decreased with increasing temperature-NO x reduction by CO (g) and C (s) were predominant at high temperatures, [22,23] but the opposite trend was verified by other studies. [6,24] NO x increased when oxygen content increased-more O 2 was available to react with fuel-N. [23,25] Some studies showed that CaO could enhance the conversion ratio of nitrogen providing a non-desirable effect. [6,[26][27][28][29][30] Wu et al [31] found that FeO played a significant role in decreasing NO concentration formed during coal combustion at 1273 K (1000°C).…”

“…[6,24] NO x increased when oxygen content increased-more O 2 was available to react with fuel-N. [23,25] Some studies showed that CaO could enhance the conversion ratio of nitrogen providing a non-desirable effect. [6,[26][27][28][29][30] Wu et al [31] found that FeO played a significant role in decreasing NO concentration formed during coal combustion at 1273 K (1000°C). His research also showed that FeO ability to reduce NO gas increases with experiment temperature.…”