Article
Chemistry, Physical
Jiseon Kim, Chong Min Chung, Kangwoo Cho, Tai Hak Chung
Summary: This study provides practical guidelines for the gas to solids (G/S) ratio as the governing parameter in electroflotation (EF) based on theoretical estimates and experiments for clarification of activated sludge.
Article
Engineering, Environmental
Yugo Takabe, Kotaro Ida
Summary: This study successfully achieved the precipitation of calcium phosphate (CaP) and sludge thickening through electrolysis using an anode covered with bivalve shells. The results demonstrated efficient removal of phosphate, shortened precipitation time, and a significant reduction in phosphate concentration in the effluent.
Article
Engineering, Chemical
Xiawen Yi, Huihui Zhong, Ming Xie, Pin Zhao, Weilong Song, Xinhua Wang
Summary: The fouling behaviors and mechanisms of forward osmosis (FO) membrane in sludge thickening (FO-MST) process were investigated. Results showed that sludge concentration had a significant impact on FO membrane fouling, which could be divided into three stages.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Engineering, Environmental
Xiawen Yi, Huihui Zhong, Ming Xie, Xinhua Wang
Summary: The MF-FO reactor achieved a thickening of MLSS concentration to 50 g/L after 10 days, with superior effluent quality.
Article
Engineering, Environmental
M. S. Romero-Guiza, X. Flotats, R. Asiain-Mira, J. Palatsi
Summary: This study shows that upgrading the sludge line of a wastewater treatment plant using advanced process control strategies can optimize sludge thickening, improve anaerobic digestion performance, reduce chemical consumption, increase energy self-sufficiency, and decrease sludge production.
Article
Environmental Sciences
Sadiye Kosar, Onur Isik, Busra Cicekalan, Hazal Gulhan, Seyma Cingoz, Mustafa Yoruk, Hale Ozgun, Ismail Koyuncu, Mark C. M. van Loosdrecht, Mustafa Evren Ersahin
Summary: Achieving a neutral/positive energy balance without compromising discharge standards is a key goal in wastewater treatment plants. This study explores the coupling of high-rate activated sludge (HRAS) process with aerobic granular sludge (AGS) process as an energy-efficient pre-treatment option. The results show that feeding the AGS process with a mixture of HRAS process effluent and raw municipal wastewater can increase energy recovery potential and maintain high effluent quality.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Zixuan Liang, Jing Yi, Qun Gu, Xiaohu Dai
Summary: This study compares the performance of the full-scale conventional activated sludge (CAS) and the high-concentration powder carrier bio-fluidized bed (HPB) processes. The results show that the HPB process has a higher total nitrogen removal efficiency and can stabilize the effluent's total nitrogen below 10 mg/L, while reducing sludge production.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Guanying Wang, Guanglei Qiu, Jian Wei, Zhuang Guo, Weiye Wang, Xiaoling Liu, Yonghui Song
Summary: With the development of industries, explosion accidents occur frequently during production, transportation, usage, and storage of hazardous chemicals. The activated carbon-activated sludge (AC-AS) process shows promising potential in efficiently treating wastewater with high concentrations of toxic compounds. In this study, AC and AS were used to treat wastewater from an explosion accident, resulting in increased removal efficiency and shortened treatment time compared to traditional processes. Metagenomic analysis and spectroscopy were used to explore the enhancement mechanism of AC on AS, revealing the important roles of certain bacteria and genes in pollutant degradation. This study demonstrates the universal characteristics of the AC-AS process for treating wastewater with high levels of organic matter and toxicity.
ENVIRONMENTAL RESEARCH
(2023)
Article
Engineering, Environmental
Seth Apollo, Manana Seretlo, John Kabuba
Summary: This study presents the performance of a modified AS system, known as the SPRAS process, which achieved significant sludge reduction through in situ cell lysis. The SPRAS plant had a sludge yield of 0.0823 kg TSS/kg COD, much lower than the conventional activated sludge process. The process demonstrated adequate sludge settling ability and achieved high reductions in ammonia and COD.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Kristina Kokina, Linda Mezule, Kamila Gruskevica, Romans Neilands, Ksenija Golovko, Talis Juhna
Summary: Knowledge about inhibition of activated sludge process is crucial for control of the most applied biological wastewater treatment technology. The inhibition effect of rapid variations of pH in wastewater on activated sludge was investigated in laboratory-scale sequencing batch reactors (SBR). The experiment with pH 8.5 showed a low risk of inhibition of second step nitrification (conversion of nitrites to nitrates), while the experiment with pH 6.5 showed inhibition of first-step nitrification (conversion of ammonia to nitrites).
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Environmental
M. J. Gallardo-Altamirano, P. Maza-Marquez, S. Perez, B. Rodelas, C. Pozo, F. Osorio
Summary: The study investigated the operation of an A2O-IFAS system for removing emerging pollutants, particularly pharmaceutical compounds. Results showed that the A2O-IFAS system achieved similar or higher removal efficiency for organic matter and nutrients compared to conventional systems, even with low sludge retention time and mixed liquor suspended solid. The system demonstrated promising removal rates for certain pharmaceutical compounds, indicating its potential as a cost-effective upgrade for wastewater treatment plants.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Engineering, Environmental
Margarida Campinas, Rui M. C. Viegas, Cristina M. M. Almeida, Antonio Martins, Catarina Silva, Elsa Mesquita, Sofia Silva, Maria Rosario Coelho, Maria Joao Benoleil, Maria Joao Rosa, Vitor Vale Cardoso
Summary: Adding powdered activated carbon to traditional activated sludge reactors is an effective method for controlling pharmaceutical compound discharge in municipal wastewater treatment. The full-scale test showed that proper doses of powdered activated carbon significantly reduced the discharge of recalcitrant pharmaceutical compounds, improving effluent quality without increasing energy consumption. Additionally, powdered activated carbon had a positive effect on sludge treatment, increasing sludge production.
JOURNAL OF WATER PROCESS ENGINEERING
(2022)
Article
Environmental Sciences
Mateusz Sobczyk, Agnieszka Pajdak-Stos, Edyta Fialkowska, Lukasz Sobczyk, Janusz Fyda
Summary: The study found that the species composition and community structure of activated sludge are greatly influenced by individual features of the treatment plants, with temperature being the most critical factor affecting changes in the microbial community. However, the reduction rates of COD, BOD5, SS, and TN were not sufficient to explain the variations in protozoa and metazoan community composition.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Review
Agricultural Engineering
Sining Zhou, Min Liu, Ben Chen, Lianpeng Sun, Hui Lu
Summary: This review provides a systematic introduction to microbubble and nanobubble aeration in the activated sludge process, highlighting their potential applications and mechanism for improving gas-liquid mass transfer. It also discusses the recent advances and effects of microbubble and nanobubble aeration in wastewater treatment.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
C. Bretas Alvim, S. Castelluccio, E. Ferrer-Polonio, M. A. Bes-Pia, J. A. Mendoza-Roca, J. Fernandez-Navarro, J. L. Alonso, I Amoros
Summary: According to previous research, wastewater treatment plants can retain over 90% of microplastics found in wastewater, but a significant portion of the removed microplastics may be retained in the sludge, potentially causing environmental issues. This study found that microplastics have selective effects on the bacterial community in activated sludge, but do not impact the abundance of nitrifying and denitrifying bacteria in the sludge.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Engineering, Environmental
Ericson Escobedo, Kangwoo Cho, Yoon-Seok Chang
Summary: This study evaluated wastewater treatment by electrochemical activation of hydrogen peroxide (EAHP), persulfate (EAP), and free chlorine (EAFC) to simultaneously eliminate aqueous organic matter and heavy metals. The results showed that EAHP was the most effective option, providing non-toxic effluent with the lowest cost under optimized conditions.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Engineering, Environmental
Mingizem Gashaw Seid, Jeehye Byun, Wooyul Kim, Kangwoo Cho, Seok Won Hong
Summary: The study investigated the effectiveness of photocatalytic pretreatment in minimizing the formation potentials of carcinogenic nitrosamines during water chloramination. The results showed that PCP was more effective for reducing nitrosamine-FPs during post-chloramination, but its efficacy varied with water source, pretreatment pH, and irradiation time. Strategies such as oxygen addition, N-de(m)ethylation, and N-dealkylation were found to be responsible for decreasing nitrosamine-FPs.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Sukhwa Hong, Kahyun Ham, Jeemin Hwang, Sinwoo Kang, Min Ho Seo, Young-Woo Choi, Byungchan Han, Jaeyoung Lee, Kangwoo Cho
Summary: In this study, a highly efficient and stable oxygen evolution reaction (OER) electrocatalyst is developed by using scalable solution casting method to deposit doped nanoparticles on Ni foam. Advanced X-ray absorption spectroscopy and density functional theory calculations reveal the changes in catalytic active sites, providing new insights for precious-metal doped Ni-Fe oxide electrocatalysts.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Aseom Son, Jiho Lee, Mingizem Gashaw Seid, Evandi Rahman, Jaewan Choe, Kangwoo Cho, Jaesang Lee, Seok Won Hong
Summary: This study investigates the dual role of Ti3+ self-doped TiO2 nanotubes (bl-TNA) as both an anode and a cathode in the photoelectrochemical (PEC) oxidative treatment of organic contaminants. The symmetric PEC system with bl-TNA photoelectrodes demonstrates higher interfacial charge transfer, photoresponsive activity, and kinetic constant for organic degradation compared to the asymmetric system with Ti cathodes. The addition of cathodic peroxydisulfate (PDS) enhances the photoactivity of the electrodes, particularly at the cathode.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Engineering, Chemical
Sungho Bae, Yerin Kim, Seok Kim, Chong Min Chung, Kangwoo Cho
Summary: This study investigated the effects of ball-milling on the selective separation of SO42- using powdered activated carbon through capacitive deionization. The results showed that ball-milling could modify the pore size distribution and surface charge to enhance the selectivity of SO42-. The experiments with symmetric and asymmetric electrodes demonstrated the improved selectivity and ion swapping behavior induced by ball-milling.
Article
Engineering, Environmental
Woonghee Lee, Seok Kim, Kangwoo Cho
Summary: This study applied scanning electrochemical microscopy (SECM) to detect dissolved O3, which is important for water treatment. Au ultramicroelectrodes biased at 0.62 V RHE showed superior activity and selectivity for O3 reduction compared to Pt analogues. SECM allowed quantitative in situ interrogation of ozone evolution reaction (OZER) electrocatalysts and visualized the improved OZER activity by SiOx overlayer on NSS.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Mingizem Gashaw Seid, Aseom Son, Kangwoo Cho, Jeehye Byun, Seok Won Hong
Summary: This study aimed to investigate the structural effect of engineered TiO2 samples on the formation of major nitrosamines during photocatalysis. The nitrogen-containing impurities and leached metal ions from doped-TiO2 samples could exacerbate nitrosamine formation potential. Pre-purification and immobilization of doped-TiO2 samples are suggested to remove a considerable amount of nitrosamines.
Article
Chemistry, Physical
Junhyung Park, Eun Ju Hwang, Sukhwa Hong, Kangwoo Cho
Summary: This study found that coating bismuth-titanium composite oxides on top of iridium-based anodes could enhance the efficiency of the chlorine evolution reaction for chlor-alkali and water treatment. The mechanism and effects of bismuth needed further clarification. Bi x Ti10-xO y heterojunction layers were prepared on an existing iridium-tantalum oxide anode, and various characterizations and electrolysis experiments were performed. The results showed that the outer layer of Bi12TiO20 and β-Bi2O3 could improve the reactivity and selectivity of the chlorine evolution reaction, but the loosely packed and thick overlayers worsened the efficiency and stability.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Nanoscience & Nanotechnology
Evandi Rahman, Jiho Lee, Seung Ji Lim, Aseom Son, Jiyun Han, Kangwoo Cho, Seok Won Hong
Summary: We developed low-cost cathodes for the electrochemical reduction of NO3- in wastewater. By simple reconstruction of stainless steel, we obtained cathodes with superior stability and efficiency, making them suitable for NO3- removal in wastewater treatment.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Minjeong Kim, Jaemin Choi, Woonghee Lee, Yong-Yoon Ahn, Hangil Lee, Kangwoo Cho, Jaesang Lee
Summary: This study compared hydrogen annealing and cathodic polarization as strategies to fabricate electrically conducting titanium oxides through oxygen non-stoichiometry creation for anodic water treatment. Ti4O7 exhibited higher electrical conductivity and superior performance in chlorine evolution and anodic organic oxidation. Hydroxyl radical primarily contributed to anodic oxidation, and self-doped TiO2 underwent more drastic performance reduction and vulnerability to activity loss and structural damage.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Editorial Material
Chemistry, Physical
Kangwoo Cho, Wonyong Choi, Detlef Bahnemann
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Editorial Material
Chemistry, Physical
Kangwoo Cho, Wonyong Choi, Detlef Bahnemann
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Nanoscience & Nanotechnology
Evandi Rahman, Sukhwa Hong, Jaesang Lee, Seok Won Hong, Kangwoo Cho
Summary: This study reports a Ni0.33Fe0.67Oy/TiO2 heterojunction anode prepared by sol-gel coating and thermal decomposition, which showed comparable ClER efficiency to benchmarking Ir7Ta3Oy/TiO2 in neutral NaCl solutions. The outer TiO2 was identified as the active ClER center. Ni0.33Fe0.67Oy exhibited superior OER activity compared to other Fe-doped Ni oxides, indicating its potential as an ohmic contact for ClER.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Seok Kim, Seokhyun Choung, Woonghee Lee, Sungho Bae, Jeong Woo Han, Kangwoo Cho
Summary: This study demonstrates a heterojunction strategy to tune the activity and selectivity of a Ni-Sb-SnO2 (NSS) anode in the electrochemical ozone evolution reaction (OZER). By optimizing the loading of SiOx, NSS/SiOx exhibits improved current efficiency and retarded oxygen evolution in OZER.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Eun-Tae Yun, Woonghee Lee, Yong-Yoon Ahn, Jaemin Choi, John D. Fortner, Kangwoo Cho, Seungkwan Hong, Jaesang Lee
Summary: In this study, a nitrogen-doped graphene film was successfully fabricated and demonstrated superior electrical conductivity and treatment efficiency in oxidative organic degradation and persulfate conversion reactions. Furthermore, the graphene film also showed a dual role as a carbon catalyst and cathode.
ENVIRONMENTAL SCIENCE-NANO
(2022)
Article
Agricultural Engineering
Yinping Xiang, Meiying Jia, Rui Xu, Jialu Xu, Lele He, Haihao Peng, Weimin Sun, Dongbo Wang, Weiping Xiong, Zhaohui Yang
Summary: This study investigated the impact of the non-antibiotic pharmaceutical carbamazepine on antibiotic resistance genes (ARGs) during anaerobic digestion. The results showed that carbamazepine induced the enrichment of ARGs and increased the abundance of bacteria carrying these genes. It also facilitated microbial aggregation and intercellular communication, leading to an increased frequency of ARGs transmission. Moreover, carbamazepine promoted the acquisition of ARGs by pathogens and elevated their overall abundance.
BIORESOURCE TECHNOLOGY
(2024)
Review
Agricultural Engineering
Weixin Zhao, Tianyi Hu, Hao Ma, Dan Li, Qingliang Zhao, Junqiu Jiang, Liangliang Wei
Summary: This review summarizes the effects and potential mechanisms of biochar on microbial behavior in AD systems. The addition of biochar has been found to promote microbial colonization, alleviate stress, provide nutrients, and enhance enzyme activity. Future research directions include targeted design of biochar, in-depth study of microbial mechanisms, and improved models.
BIORESOURCE TECHNOLOGY
(2024)
Review
Agricultural Engineering
Christina Karmann, Anna Magrova, Pavel Jenicek, Jan Bartacek, Vojtech Kouba
Summary: This review assesses nitrogen removal technologies in reject water treatment, highlighting the differences in environmental impacts and economic benefits. Partial nitritation-anammox shows potential for economic benefits and positive environmental outcomes when operated and controlled properly.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Wei-Hao Huang, Ying-Ju Chang, Duu-Jong Lee
Summary: This study modified pinecone biochar with layered double hydroxide (LDH) to enhance its adsorption capacity for heavy metal and phosphate ions. The LDH-biochar showed significantly improved adsorption capacities for Pb2+ and phosphate, and a slight increase for Cu2+ and Co2+. The LDH layer enhanced the adsorption through various mechanisms.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Chao Song, Fanfan Cai, Shuang Yang, Ligong Wang, Guangqing Liu, Chang Chen
Summary: This paper developed a machine learning model to predict the biochemical methane potential during anaerobic digestion. Model analysis identified lignin content, organic loading, and nitrogen content as key attributes for methane production prediction. For feedstocks with high cellulose content, early methane production is lower but can be improved by prolonging digestion time. Moreover, lignin content exceeding a certain value significantly inhibits methane production.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Sang Min Lee, Ju Young Lee, Ji-Sook Hahn, Seung-Ho Baek
Summary: This study successfully developed an efficient platform strain using Yarrowia lipolytica for the bioconversion of renewable resources into adipic acid, achieving a remarkable increase in production level.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Sefkan Kendir, Matthias Franzreb
Summary: This study presents a novel approach using magnetic separation to efficiently harvest freshwater microalgae, Chlorella vulgaris. By combining pH-induced calcium phosphate precipitation with cheap natural magnetite microparticles, harvesting efficiencies up to 98% were achieved in the model medium.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Ishaq Kariim, Ji-Yeon Park, Wajahat Waheed Kazmi, Hulda Swai, In-Gu Lee, Thomas Kivevele
Summary: The impact of reaction temperature, residence time, and ethanol: acetone on the energy compositions and yield enhancement of biocrudes was investigated. The results showed that under appropriate conditions, biocrudes with high energy and low oxygen content can be obtained, indicating a high potential for utilization.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Xiyue Zhang, Xiyao Li, Liang Zhang, Yongzhen Peng
Summary: Intermittent aeration is an innovative approach to enhance nitrogen removal in low carbon-to-nitrogen ratio municipal sewage, providing an efficient strategy for the continuous plug-flow AOA process.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Xu Yang, Mahmoud Mazarji, Mengtong Li, Aohua Li, Ronghua Li, Zengqiang Zhang, Junting Pan
Summary: This study investigated the impact of magnetite on the nitrogen cycle of pig manure biostabilisation. The addition of magnetite increased N2O emissions and decreased NH3 emissions during composting. It also increased the total nitrogen content but should be considered for its significant increase in N2O emissions in engineering practice.
BIORESOURCE TECHNOLOGY
(2024)
Review
Agricultural Engineering
Ty Shitanaka, Haylee Fujioka, Muzammil Khan, Manpreet Kaur, Zhi-Yan Du, Samir Kumar Khanal
Summary: The market value of microalgae has exponentially increased in the past two decades, thanks to their applications in various industries. However, the supply of high-value microalgal bioproducts is limited due to several factors, and strategies are being explored to overcome these limitations and improve microalgae production, thus increasing the availability of algal-derived bioproducts in the market.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Martin Kerner, Thorsten Wolff, Torsten Brinkmann
Summary: The efficiency of using enriched CO2 from flue gas for large-scale production of green microalgae has been studied. The results show that the use of membrane devices and static mixers can effectively improve the CO2 recovery rate and maintain the suitable pH and temperature during cultivation, achieving a more economical and sustainable microalgae production.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Rui Ma, Ji Li, Rd Tyagi, Xiaolei Zhang
Summary: This review summarizes the microorganisms capable of using CO2 and CH4 to produce PHAs, illustrating the production process, factors influencing it, and discussing optimization techniques. It identifies the challenges and future prospects for developing economically viable PHAs production using GHGs as a carbon source.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Bing Wang, Peng Zhang, Xu Guo, Xu Bao, Junjie Tian, Guomin Li, Jian Zhang
Summary: The addition of zeolite in the co-composting of chicken manure and straw significantly reduced the emissions of ammonia and N2O, and increased the nitrate content. Zeolite also promoted the abundance of nitrification genes and inhibited the expression of denitrification genes.
BIORESOURCE TECHNOLOGY
(2024)
Article
Agricultural Engineering
Rohit Dey, Franziska Ortiz Tena, Song Wang, Josef Martin Messmann, Christian Steinweg, Claudia Thomsen, Clemens Posten, Stefan Leu, Matthias S. Ullrich, Laurenz Thomsen
Summary: This study investigated the operation of a 1000L microalgae-based membrane photobioreactor system for continuous secondary wastewater treatment. The research focused on a green microalgae strain called Desmodesmus sp. The study aimed to understand key trends and optimization strategies by conducting experiments in both summer and winter seasons. The findings showed that maintaining low cell concentrations during periods of light inhibition was beneficial for nutrient uptake rates. Effective strategies for enhancing algae-based wastewater treatment included cell mass recycling and adjusting dilution rates based on light availability.
BIORESOURCE TECHNOLOGY
(2024)