Desulfurization and Denitrification Performance of Modified Rice Husk Ash-Carbide Slag Absorbent

Yali Wang; Xiaoning Han; Meina Chen; Suping Cui; Xiaoyu Ma; Liwei Hao

doi:10.3390/ma14010068

Desulfurization and Denitrification Performance of Modified Rice Husk Ash-Carbide Slag Absorbent

Materials (Basel). 2020 Dec 25;14(1):68. doi: 10.3390/ma14010068.

Authors

Yali Wang¹, Xiaoning Han¹, Meina Chen¹, Suping Cui¹, Xiaoyu Ma¹, Liwei Hao²

Affiliations

¹ Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China.
² State Key Laboratory of Solid Waste Reuse for Building Materials, Beijing Building Materials Academy of Science Research, Beijing 100041, China.

Abstract

In the cement industry, SO₂ and NOx are generally removed separately. There are many problems, such as large area, high investment cost, secondary pollution and so on. Desulfurization and denitrification technology have become a frontier research direction in the field of air pollution control. In this paper, rice husk ash and carbide slag were compounded and modified to prepare modified rice husk ash-carbide slag composite absorbent, and its desulfurization and denitrification performance and mechanism were studied. The results showed that the NO conversion and SO₂ conversion of the modified rice husk ash-carbide slag composite absorbent increased by 44% and 2%, respectively, at 700 °C. Fibrous calcium silicate and calcium silicoaluminate hydrates were formed during the hydration process, which made the specific surface area of the absorbent larger and provided more reactive sites. The hydration process increases the content of oxygen-containing functional groups, decreases the hydroxyl/ether C-O functional groups, and increases the content of carboxyl-COO functional groups are conducive to the denitrification reaction.

Keywords: carbide slag; desulfurization and denitrification; hydration; modification; rice husk ash.