title: Combined effects of Fenton peroxidation and CaO conditioning on sewage sludge thermal drying.
abstract: Joint application of Fenton's reagent and CaO can dramatically enhance sludge dewaterability, thus are also likely to affect subsequent thermal drying process. This study investigated the synergistic effects of the two conditioners on the thermal drying behavior of sewage sludge and the emission characteristics of main sulfur-/nitrogen-containing gases. According to the results, Fenton peroxidation combined with CaO conditioning efficiently promoted sludge heat transfer, reduced the amounts of both free and bound water, and created porous structure in solids to provide evaporation channels, thus producing significant positive effects on sludge drying performance. In this case, the required time for drying was shortened to one-third. Additionally, joint usage of Fenton's reagent and CaO did not increase the losses of organic matter during sludge drying process. Meanwhile, they facilitated the formation of sulfate and sulfonic acid/sulfone, leading to sulfur retention in dried sludge. Both of Fenton peroxidation and CaO conditioning promoted the oxidation, decomposition, and/or dissolution of protein and inorganic nitrogen in sludge pre-treatment. As a consequence, the emissions of sulfurous and nitrogenous gases from dewatered sludge drying were greatly suppressed. These indicate that combining Fenton peroxidation with CaO conditioning is a promising strategy to improve drying efficiency of sewage sludge and to control sulfur and nitrogen contaminants during sludge thermal drying process.
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Wu
authors.affiliation: School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Jiakuan
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China. Electronic address: hyao@mail.hust.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Yao
mesh_terms: D000393:Air Pollutants / Q000737:chemistry; D000397:Air Pollution / Q000517:prevention & control; D017610:Calcium Compounds / Q000737:chemistry*; D003246:Conservation of Energy Resources; D005740:Gases / Q000737:chemistry; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D017672:Nitrogen Compounds / Q000737:chemistry; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D013457:Sulfur Compounds / Q000737:chemistry
chemical_list: D000393:Air Pollutants; D017610:Calcium Compounds; C045076:Fenton's reagent; D005740:Gases; D017672:Nitrogen Compounds; D010087:Oxides; D012722:Sewage; D013457:Sulfur Compounds; D006861:Hydrogen Peroxide; C016538:lime; D007501:Iron
keywords: CaO; Drying; Fenton’s reagent; Nitrogen transformation; Sewage sludge; Sulfur transformation