title: Inhibitory effects of CaO/Fe2O3 on arsenic emission during sewage sludge pyrolysis.
abstract: This work aimed to investigate effects and reaction mechanisms of CaO/Fe2O3 on emission behaviors of arsenic during sewage sludge pyrolysis. The results showed that 24.8-54.2%, 26.4-60.4% and 27.7-63.1% of arsenic escaped from three samples when pyrolysis process happened at 723, 923 and 1123K respectively. And the sludge which contained higher calcium and iron contents released less arsenic than others. External CaO and Fe2O3 were added into the sewage sludge to study their effects on arsenic emissions during pyrolysis, where both of them inhibited arsenic emission effectively, especially at high temperatures. With the help of thermogravimetry analysis and X-ray fluorescence, inhibitory mechanisms of CaO/Fe2O3 on arsenic emission during sewage sludge pyrolysis were studied. CaO could react with As2O3, As2S3 and NaAsO2 to form nonvolatile substances, such as Ca(AsO2)2; while Fe2O3 could react with NaAsO2 to generate certain substances which was stable below 1123K.
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Hengda
authors.initials: H
authors.lastname: Han
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China; China-EU Institute for Clean and Renewable Energy at Huazhong University of Science and Technology, Wuhan 430074, Hubei, China. Electronic address: husong_hust@hotmail.com.
authors.forename: Song
authors.initials: S
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Chaofeng
authors.initials: C
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Long
authors.initials: L
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xiang
authors.affiliation: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China; China-EU Institute for Clean and Renewable Energy at Huazhong University of Science and Technology, Wuhan 430074, Hubei, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Su
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D000077237:Arsenic Trioxide; D001152:Arsenicals / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D002681:China; D005290:Ferric Compounds / Q000737:chemistry*; D006358:Hot Temperature; D010087:Oxides / Q000737:chemistry*; D012722:Sewage / Q000032:analysis / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission; D013818:Thermogravimetry; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D001152:Arsenicals; D017610:Calcium Compounds; D005290:Ferric Compounds; D010087:Oxides; D012722:Sewage; C000499:ferric oxide; C016538:lime; D001151:Arsenic; D000077237:Arsenic Trioxide
keywords: Arsenic (As); Calcium oxide (CaO)/iron oxide (Fe(2)O(3)); Inhibitory mechanisms; Pyrolysis; Sewage sludge