Mutual promotion effect of SO₂ and NOx during yellow phosphorus and phosphate rock slurry adsorption process

Abstract

Removing SO2 and NOx released from middle and small‐scaled coal‐burning boiler is one important strategy for air pollution control. Herein, we first report a novel process on simultaneous eliminating SO2 and NOx at low temperature, by employing large scale and cheap sources of phosphorus sludge and phosphate rock slurry. The results showed that 100% desulfurization and denitrification efficiency can be obtained, and there exhibited a significant mutual‐promoting effect between SO2 and NOx abatement processes. Based on characterizations and theoretical calculation results, it was found that the active substances produced by the interaction of sulfur and nitrogen species played a significant role in promoting the removal of SO2 and NOx. Compared with traditional purification technology, this process can achieve simultaneous desulfurization and denitrification with no discharge of secondary pollutants, and can be regarded as a new and economic technology for efficient removal of SO2 and NOx in industrial scale.

Recent Advances in Elimination of SO2 and NOx from Flue Gas Employing Phosphorus Sludge and Phosphate Rock

“…At the same time, the formed oxidized substances (SO 4 •– , SO 5 •– , and HSO 5 – ) enhance the conversion of NO and NO 2 toward NO 3 – by reactions –, giving rise to a high denitrification efficiency. Accordingly, SO 2 and NO x are strongly absorbed through their beneficial synergistic effects NO 2 + HSO 3 − → SO 3 • − + HNO 2 SO 5 • − + NO → SO 4 • − + NO 2 SO 4 • − + NO → NO 2 + SO 3 • − SO 4 • − + NO + normalH + → SO 3 + HNO 2 SO 4 • − + NO 2 + ...…”

“…Schematic diagram of the mutual promotion in removal of SO 2 and NO x . Reprinted with permission from ref . Copyright 2021 Wiley.…”

“…The recovery and utilization of phosphorus resources are of great importance for sustainable development. − China’s annual mining output of phosphate rock is up to 90 million tons, ranking first in the world. Approximately 15% of phosphate rock is applied to yellow phosphorus production, and 85% of it is used for wet-process phosphoric acid production to manufacture fertilizers . In the production process of yellow phosphorus (P 4 ), a large amount of phosphorus sludge is generated, mainly composed of yellow phosphorus, dust, and water.…”

Effective absorption of SO2 by imidazole‐based protic ionic liquids with multiple active sites: Thermodynamic and mechanical studies

“…Sulfur dioxide (SO 2 ) released by fossil fuel combustion is the main source of atmospheric pollution. The high toxicity of SO 2 poses a serious threat to human health and the environment 1,2 . For instance, SO 2 emission can lead to the formation of acid rain, 3 which severely irritates the quality of ecosystems and the environment 4 .…”

Experimental Investigation of SO2 Removal from Flue Gases by Cleaning with Solution of Lime Suspension and Formic Acid

“…Nie et al [9] researched the simultaneous removal of SO 2 and NO X from flue gases created by burning coal in medium and small boilers. Phosphoric and phosphate slurry were used as additives.…”