Ultrasonic and Thermal Pretreatments on Anaerobic Digestion of Petrochemical Sludge: Dewaterability and Degradation of PAHs.
Effects of different pretreatment methods on sludge dewaterability and polycyclic aromatic hydrocarbons (PAHs) degradation during petrochemical sludge anaerobic digestion were studied. Results showed that the total biogas production volume in the thermal pretreatment system was 4 and 5 times higher than that in the ultrasound pretreatment and in the control system, and the corresponding volatile solid removal efficiencies reached 28%, 15%, and 8%. Phenanthrene, paranaphthalene, fluoranthene, benzofluoranthene, and benzopyrene removal rates reached 43.3%, 55.5%, 30.6%, 42.9%, and 41.7%, respectively, in the thermal pretreatment system, which were much higher than those in the ultrasound pretreatment and in the control system. Moreover, capillary suction time (CST) of sludge increased after pretreatment, and then reduced after 20 days of anaerobic digestion, indicating that sludge dewaterability was greatly improved after anaerobic digestion. The decrease of protein and polysaccharide in the sludge could improve sludge dewaterability during petrochemical sludge anaerobic digestion. This study suggested that thermal pretreatment might be a promising enhancement method for petrochemical sludge solubilization, thus contributing to degradation of the PAHs, biogas production, and improvement of dewaterability during petrochemical sludge anaerobic digestion.
College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
Jun
J
Zhou
College of Environment, Nanjing Tech University, Nanjing, China.
Weizhong
W
Xu
Sino-forest Applied research Centre for pearl river delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region, China.
Jonathan W C
JW
Wong
College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
Xiaoyu
X
Yong
Lab of Waste Valorisation and Water Reuse, Qingdao Institute of Bioenergy and Bio process Technology, Chinese Academy of Sciences, Qingdao, China.
Binghua
B
Yan
College of Environment, Nanjing Tech University, Nanjing, China.
Xueying
X
Zhang
College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
Honghua
H
Jia
D000693:Anaerobiosis; D002617:Chemical Industry; D006358:Hot Temperature; D000066388:Oil and Gas Industry; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012722:Sewage / Q000032:analysis; D014465:Ultrasonics; D055549:Volatile Organic Compounds / Q000032:analysis; D062065:Wastewater / Q000032:analysis; D018508:Water Purification / Q000379:methods*
D011084:Polycyclic Aromatic Hydrocarbons; D012722:Sewage; D055549:Volatile Organic Compounds; D062065:Wastewater