Article
Engineering, Chemical
Junjie Yu, Hui Xu, Xiaofang Yang, Hongyan Sun, Zhiyuan Jin, Dongsheng Wang
Summary: This study investigates the growth mechanism and properties of HA-floc under different stirring conditions. The results show that HA is removed in the early stages and does not vary significantly during floc growth. The stirring condition does not affect the removal of HA, but has a remarkable effect on floc growth and structure.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Engineering, Environmental
Jamila El Gaayda, Fatima Ezzahra Titchou, Issam Barra, Ilham Karmal, Hanane Afanga, Hicham Zazou, Pow-Seng Yap, Zurina Zainal Abidin, Mohamed Hamdani, Rachid Ait Akbour
Summary: This study evaluated the efficiency of Moringa oleifera seed powder (MOSP) as a natural coagulant for removing turbidity and anionic dye from synthetic wastewater. The results showed that MOSP had a high removal efficiency for both turbidity and dye, and could be considered as an alternative to chemical coagulants due to its environmental friendliness.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Geochemistry & Geophysics
Yuping Fan, Yangyang Zhang, Xianshu Dong, Xiaomin Ma, Na Li, Wei Jin
Summary: This study investigated the impact of coagulant type and dosage on the clarity, zeta potential, floc size, and floc structure of a coal slurry suspension. The findings showed that trivalent ions had lower critical coagulation concentrations and AlCl3 and FeCl3 had a greater effect on initial settling. Additionally, trivalent ions significantly decreased the supernatant turbidity at lower dosages, enhancing the coagulation effect.
Article
Engineering, Chemical
Jiangya Ma, Rui Zhang, Wei Xia, Yanli Kong, Yong Nie, Yahua Zhou, Chi Zhang
Summary: A novel covalently bonded composite coagulant CAFM was synthesized through UV initiation, which showed high efficiency in removing algae and turbidity from water. The use of CAFM resulted in minimal residual concentrations and the formation of compact algae flocs, highlighting its importance in drinking water treatment.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Environmental Sciences
Yu Xiang, Hui Xu, Chun-fu Li, Hailu Demissie, Kun Li, Hua Fan
Summary: The study demonstrated that the addition of algal cells could enhance fluoride removal efficiency by increasing the distribution of Al(OH)(3) in flocs. However, excessive Al3+ could damage algal cells and worsen the defluoridation effect by releasing intracellular organic matter. On the other hand, Al-13 mainly removed fluoride through ion exchange, substitution, and hydrogen bonding, maintaining defluoridation performance effectively at high dosages without damaging the integrity of algal cells.
Article
Environmental Sciences
Bo Xu, Yongzhi Chi, Yiyang Chi, Jianhai Zhao, Cuilian Fu, Xueke Wang, Sufeng Tian, Yanmei Ding
Summary: In order to improve the removal efficiencies of SS and Fe3+ in anaerobic digestion reject water, the response surface method was used to analyze the structure of the formed floc by magnetic flocculation. The optimum amounts of magnetic powder, polyaluminum chloride (PAC) and polyacrylamide (PAM) were determined for maximum removal efficiencies of 97.84% and 98.35% for SS and Fe3+ respectively. The floc treated by magnetic flocculation showed improved flocculation ability, with larger particle size, a rough and porous surface, and enhanced sedimentation performance compared to conventional coagulation.
Article
Environmental Sciences
Chao Guo, Leicheng Guo, Sarah Bass, Andrew J. Manning, Zhongwu Jin, Yinjun Zhou
Summary: The effects of different types of organic matter on fine sediment flocculation were investigated through laboratory tank experiments. Results demonstrated that the introduction of organic polymers (such as xanthan gum and guar gum) significantly enhanced flocculation, while the addition of humic acid had minimal influence. The nonionic polymer guar gum showed greater efficacy in promoting larger and more fractal flocs compared to the anionic polymer, xanthan gum. Non-linear trends were observed in the evolution of floc size and structure with increasing ratios of organic polymer concentration to kaolinite concentration.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Miao Lv, Tongtong Liu, Fan Chen, Zhaohan Zhang, Dongyi Li, Muchen Sun, Yujie Feng
Summary: The interaction between PACl and MPs dosages has significant effects on pollutant removal and turbidity reduction. The weak connection between Ala and MPs, along with the formation of MPs-Alb-HA complexes, enhances the removal efficiency of turbidity and dissolved Al in water treatment processes.
ENVIRONMENTAL RESEARCH
(2021)
Article
Engineering, Environmental
Yanxia Zhao, Huiqing Lian, Chang Tian, Haibo Li, Weiying Xu, Sherub Phuntsho, Kaimin Shih
Summary: Titanium-based coagulation has been proven effective for purifying micro-polluted water containing algae, with the presence of algae enhancing the removal of organic matter. The study found that polytitanium coagulation is highly effective in separating algae from surface water, even achieving up to 98% removal. The presence of algae in water can assist polytitanium coagulation by acting as an additional coagulant or flocculation aid.
FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING
(2021)
Article
Engineering, Environmental
Ifeoma Maryjane Iloamaeke, Nnaemeka J. Nnaji, Edith Chinyere Okpala, Augustine N. Eboatu, Theresa Uzoma Onuegbu
Summary: The study demonstrated that coagulants derived from Mercenaria mercenaria were effective in purifying paint effluent, with significant removal of color within 20 minutes. Modified coagulants showed improved performance, and a second order kinetic model was found to better fit the data for the coagulation-flocculation process.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Engineering, Chemical
Yuxuan Ye, Xianwei Yu, Liang Zhang, Qiang Li, Fei Pan, Dongsheng Xia
Summary: This study demonstrated that Fe(III) salts were more efficient in removing Cr-ace complexes compared to Al(III) salts. The removal efficiency of Cr(III) complexes decreased with an increase in the carboxyl content. Additionally, high concentrations of acetate inhibited the growth of flocs.
DESALINATION AND WATER TREATMENT
(2021)
Article
Water Resources
Hanson Mensah-Akutteh, Richard Buamah, Samuel Wiafe, Kwabena B. Nyarko
Summary: This study optimized the coagulation-flocculation treatment using response surface methodology. The results showed that specific pH, alum dose, and alkalinity conditions led to the best treatment performance. The derived model equation was able to accurately predict the response values.
APPLIED WATER SCIENCE
(2022)
Article
Environmental Sciences
Lijie Zhou, Nan Dong, Biao Ye, Wei-Qin Zhuang, Siqing Xia
Summary: Calcium ions can trigger the coagulation-flocculation process to form macro-flocculated sludge, where an elevated Ca2+ concentration in MBRs can lead to the formation of granular sludge with diameters up to 900 μm. The addition of Ca2+ can flocculate and precipitate soluble proteins and polysaccharides, resulting in a negative correlation between extracellular polymeric substances concentrations and the formation of MFS. The microbial communities in the MBRs undergo significant changes with the addition of Ca2+, affecting total nitrogen removal due to the formation of diffusion barriers by the enlarging MFS.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Yanyan Ding, Tong Li, Kaipei Qiu, Baiwen Ma, Ruijun Wu
Summary: This study showed that both membrane fouling behavior and the performance of coagulation integrated UF processes can be influenced by both the density and thickness of a cake layer formed during the processes, as well as the sedimentation time and flocs characteristics. A critical threshold of 30 minutes was observed at the lab-scale, which determines whether direct coagulation-UF (CUF) outperforms conventional coagulation-sedimentation-UF (CSUF) depending on whether the main factor affecting membrane fouling is the cake layer density or thickness.
ENVIRONMENTAL RESEARCH
(2021)
Article
Green & Sustainable Science & Technology
Zhaoyang Su, Xiaoting Wu, Wenbao Yu, Ting Liu, Xing Li, Muyang Liu, Wenzheng Yu
Summary: This study aims to identify the critical factors affecting coagulation performance in winter and provide suggestions for drinking water production under low temperature. The findings show that the absence of natural biopolymers significantly hinders floc growth at low temperature, while increasing the concentration of biopolymers can facilitate floc growth.
JOURNAL OF CLEANER PRODUCTION
(2022)
