title: Influence of organic and inorganic flocculants on the formation of PCDD/Fs during sewage sludge incineration.
abstract: Flocculants are widely used to improve the properties of sludge dewatering in industrial wastewater treatment. However, there have been no studies conducted on the influence of flocculants on the formation of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) during sewage sludge incineration. This paper selected three typical kinds of flocculants, including polyacrylamide (PAM), poly-ferric chloride (PFC), and polyaluminum chloride (PAC) flocculant, to study their influences on the formation of PCDD/Fs during sewage sludge incineration. The results indicated that PAM flocculant, which is an organic flocculant, inhibited the formation of PCDD/Fs in sewage sludge incineration, while inorganic flocculant, such as PFC and PAC flocculant, promoted the formation. The most probable explanation is that the amino content in the PAM flocculant acted as an inhibitor in the formation of PCDD/Fs, while the chlorine content, especially the metal catalyst in the PFC and PAC flocculants, increased the formation rate. The addition of flocculants nearly did not change the distribution of PCDD/F homologues. The PCDFs contributed the most toxic equivalent (TEQ) value, especially 2, 3, 4, 7, 8-PeCDF. Therefore, the use of inorganic flocculants in industrial wastewater treatment should be further assessed and possibly needs to be strictly regulated if the sludge is incinerated. From this aspect, a priority to the use of organic flocculants should be given.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China. lixd@zju.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Shengyong
authors.initials: S
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yan
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D000536:Aluminum Hydroxide / Q000737:chemistry*; D001572:Benzofurans / Q000032:analysis* / Q000737:chemistry; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins / Q000032:analysis* / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D005427:Flocculation; D017745:Incineration; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives; D012722:Sewage / Q000737:chemistry*; D018508:Water Purification; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D000536:Aluminum Hydroxide; D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins; D005290:Ferric Compounds; D000072317:Polychlorinated Dibenzodioxins; D012722:Sewage; D000099166:Polyacrylamides; C541115:polyferric chloride; C016213:aluminum oxychloride; C020887:dibenzo(1,4)dioxin
keywords: Flocculant; Incineration; PCCD/Fs; Sewage sludge; Wastewater treatment