Article
Engineering, Environmental
Chenyu Wang, Biao Gui, Chaoyue Wu, Chao He, Lucheng Li, Xiaolong Ling, Xiaojun Zuo
Summary: Hydrothermal carbonization (HTC) is a promising technology for sewage sludge (SSL) utilization. A process combining physicochemical pretreatment, namely Fenton oxidation (FO), and HTC was developed to improve the yield and performance of hydrochar produced from SSL. The combined process showed improved yield and properties of hydrochar compared to direct HTC treatment.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Environmental Sciences
Kai Chen, Yue Sun, Jun Fan, YingPeng Gu
Summary: The study investigates the use of bioleaching combined with coal fly ash (BL-CFA) process to improve sludge dewatering performance. The BL-CFA process reduces the water content of the sludge and enhances the dewatering effect. Analysis of extracellular polymeric substances (EPS), fluorescence, Fourier transform infrared (FTIR) spectroscopy, and particle size variation, along with scanning electron microscopy (SEM), reveals the mechanisms behind the improvement in sludge dewatering. The BL-CFA process shows potential for superior sludge dewatering performance.
Article
Engineering, Environmental
Neng Tao, Lingyu Hu, Di Fang, Volodymyr Tarabara, Lixiang Zhou
Summary: This study used tea polyphenols as an iron redox conversion enhancer to improve the dewatering efficiency of sludge in the Fenton oxidation process. The addition of tea polyphenols in a Fenton-like system enhanced the sludge dewaterability at neutral pH, reduced the consumption of Fenton reagents, and resulted in the decomposition of biopolymers and disintegration of bioflocs. This research suggests a new approach for cost-effective sludge dewatering technologies using the synergistic effects of plant polyphenols and advanced oxidation processes.
Article
Engineering, Environmental
Ting Li, Jiawei Yang, Yujun Zhou, Yixin Luo, Bo Zhou, Di Fang, Jiansheng Li, Lixiang Zhou
Summary: Bioleaching facilitated by iron-oxidizing bacteria is a promising and cost-effective method for sludge dewatering. Increasing the production of reactive oxygen species (ROS) through the introduction of H2O2 can significantly improve dewaterability and shorten the treatment time.
Article
Engineering, Environmental
Luyi Xing, Jia Wei, Xiaohui Liu, Yifei Zhang, Mengdie Xu, Jiamei Li, Guoping Pan, Jun Li
Summary: An innovative nitrogen-doped sludge-derived biochar (NSBC) cathode was fabricated with high ORR electrocatalytic active sites for efficient degradation of sulfamethoxazole (SMX). The study also proposed rational reaction intermediates during the EF process, paving the way for developing eco-friendly and cost-effective cathode materials in the EF system.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Engineering, Environmental
Guirong Ye, Jinghong Zhou, Renting Huang, Yingjun Ke, Yecan Peng, Yongxin Zhou, Yu Weng, Chutong Ling, Weixi Pan
Summary: Fenton sludge was converted into magnetic sludge-based biochar (SMBC) which showed excellent catalytic efficiency in activating hydrogen peroxide for the oxidative removal of methylene blue. The crystal phase of Fe oxides in SMBC strongly influenced its catalytic activity, with the catalyst obtained at 800 degrees C for 1 h exhibiting the highest degradation efficiency. Free radical quenching experiments and electron paramagnetic resonance studies revealed the involvement of various radicals in the H2O2 system, and SMBC played a crucial role in generating .OH radicals. SMBC also showed good stability in non-aerated and aqueous conditions.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Environmental Sciences
Rahim Molaey, Hatice Yesil, Baris Calli, Adile Evren Tugtas
Summary: Interest in using stabilized sewage sludge in agriculture is mainly due to its nutrient content, soil conditioning properties, and water holding capacity. This study integrated anaerobic fermentation with air-assisted ultra-sonication to assess heavy metal leaching from waste activated sludge, demonstrating effective solubilization of target metals.
Article
Engineering, Environmental
Minghao Jin, Huan Liu, Hongping Deng, Han Xiao, Geng Lu, Hong Yao
Summary: This study systematically investigated the effects of Fenton-CaO composite conditioning on the behavior of arsenic during sludge treatment. The results showed that the Fenton-CaO treatment could significantly reduce the release of arsenic and the toxicity of the products.
Article
Environmental Sciences
Jianping Yang, Xiaolei Zhu, Zejian Ai, Lijian Leng, Hailong Li
Summary: The Fenton oxidation approach was used for the efficient dewatering and upgrading of oily sludge. The approach effectively reduced the water content and improved the quality of the oil phase, while increasing the heating value of the sludge.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Environmental Sciences
Anna Siatecka, Patryk Oleszczuk
Summary: The stability of biochars derived from sewage sludge was found to be closely related to their content and character of C. Biochars with higher aromaticity, lower organic content, and higher pyrolysis temperatures were more stable, while low-temperature biochars were more susceptible to oxidation. The more aromatic structure of C limited access of O2 molecules to biochar interior, resulting in concentrated aging processes on the surface layer and less property changes.
Article
Environmental Sciences
Yuzhi Liu, Bing Li, Dengting Guo, Muhammad Tajammal Munir, Lan Song, Xiaofeng Wu, Yuefei Huang
Summary: Due to its volume and environmental concerns, sewage sludge management and treatment are significant in China. The recent prohibition of reusing sewage sludge as organic fertilizers calls for the development of alternative processes. This study reviews the development of hydrothermal processes for sewage sludge treatment and evaluates the applicability in China, considering the differences in sludge composition and land availability in urban areas.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Rahim Molaey, Hatice Yesil, Baris Calli, Adile Evren Tugtas
Summary: This study investigated the influence of volatile fatty acids (VFAs) on the solubilization of potentially toxic metals during anaerobic digestion (AD) process, and found that VFAs enhanced the solubility of Ni while Cr exhibited higher solubility at neutral pH values. The addition of readily biodegradable carbon source resulted in accumulation of VFAs, altering the speciation of Cu and Zn between organically-bound and residual fractions, leading to consistently low solubility of Zn and Cu throughout the AD process.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Engineering, Environmental
Jinxin Zheng, Chunsheng Qiu, Chenchen Wang, Jiaqi Zhao, Dong Wang, Nannan Liu, Shaopo Wang, Jingjie Yu, Liping Sun
Summary: The study showed that thermal hydrolysis treatment can reduce the oxidizable fraction of Cr, Mn, As, and Cd in sludge, increase the removal percentage of Mn and Cd in bioleached sludge, and alleviate the environmental risk of Cr, Mn, As, and Cd in bioleached sludge.
WATER SCIENCE AND TECHNOLOGY
(2021)
Article
Environmental Sciences
Javier Canas, Silvia alvarez-Torrellas, Blanca Hermana, Juan Garcia
Summary: Environmental legislation and potential nutrient recovery drive the adoption of advanced treatment technologies for biosolids waste management. This study focused on phosphorus recovery from sewage sludge using wet oxidation. The wet oxidation process achieved high removal of organic matter (up to 85% COD) and total solids (up to 75%) at elevated temperature and pressure. Both liquid and solid fractions contained high amounts of phosphorus that can be recovered. Phosphorus was successfully recovered from the liquid effluent through chemical precipitation as struvite, with a recovery rate exceeding 95%. Acid leaching of the solid fraction resulted in a phosphorus recovery rate of up to 60%, with all extracted phosphorus in the form of orthophosphate.
Article
Environmental Sciences
Asaad Olabi, Sayiter Yildiz
Summary: The study demonstrated that the combination of ultrasonic process with UV light in Fenton processes plays a crucial role in disintegration of waste sludge, especially in modified Fenton process. Under optimal conditions, the addition of ultrasound significantly improved the degree of disintegration and reduced toxicity.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)