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CONTENTS | |
Volume 15, Number 3, July 2024 |
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- Water quality management strategy based on organic matter characteristics of streams and lakes in the Namhan River Watershed Hyeonjong Youn, Chaewon Kang and Kyungik Gil
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Abstract; Full Text (1469K) . | pages 99-106. | DOI: 10.12989/mwt.2024.15.3.099 |
Abstract
This study developed an efficient management plan to improve the water quality by analyzing fluctuations in the ratio and amount of various organic substances in streams considering watershed characteristics and rainfall patterns. Monitoring was conducted on three streams and one lake over seven sessions during wet and dry seasons. Water quality indicators including total organic (TOC), refractory dissolved organic (RDOC), and particulate organic (POC) carbons were analyzed using high-temperature combustion oxidation. The three streams (Cheongmi, Yanghwa, and Bokha) displayed high TOC concentrations during the rainy season because the accumulated organic substances from the dry season were washed away by rainfall. By contrast, Paldang Lake exhibited a substantial decrease in TOC concentration due to dilution, which was influenced by watershed and rainfall characteristics. Across all streams and lakes, dissolved organic carbon (DOC) accounted for the highest proportion, at 77.5% of TOC, with RDOC making up 91% of DOC and 71% of TOC. Although POC contributed a small annual proportion to annual TOC, the concentration rapidly increased during late spring and early summer, with increases of 40.403%, 25.99%, and 27.388% in Cheongmi, Yanghwa, and Bokha, respectively. Continuous monitoring of RDOC is essential to identify seasonal fluctuations and changes due to rainfall events. Furthermore, intensive POC management during the rainy season, particularly in May and June, is potentially economical and efficient for water quality management.
Key Words
dry season; rainfall; refractory organic substances; total organic carbon; wet season
Address
Hyeonjong Youn, Chaewon Kang and Kyungik Gil: Department of Civil Engineering, Seoul National University of Science and Technology, 232, Gongneung-ro, Nowon-gu, Seoul, South Korea, 01811
- Thermal based adsorption of daily food waste with the test of AI grey calculations ZY Chen, Huakun Wu, Yahui Meng, ZY Gu and Timothy Chen
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Abstract; Full Text (686K) . | pages 107-115. | DOI: 10.12989/mwt.2024.15.3.107 |
Abstract
This study proposes the recycling of MVS as a value-added product for the removal of phosphate from aqueous solutions. By comparing the phosphate adsorption capacity of each calcined adsorbent at each temperature of MVS, it was determined that the optimal heat treatment temperature of MVS to improve the phosphate adsorption capacity was 800 °C. MVS-800 suggests an adsorption mechanism through calcium phosphate precipitation. Subsequent kinetic studies with MVS-800 showed that the PFO model was more appropriate than the PSO model. In the equilibrium adsorption experiment, through the analysis of Langmuir and Freundlich models, Langmuir can provide a more appropriate explanation for the phosphate adsorption of MVS-800. This means that the adsorption of phosphate by MVS-800 is uniform over all surfaces and the adsorption consists of a single layer. Thermodynamic analysis of thermally activated MVS-800 shows that phosphate adsorption is an endothermic and involuntary reaction. MVS-800 has the highest phosphate adsorption capacity under low pH conditions. The presence of anions in phosphate adsorption reduces the phosphate adsorption capacity of MVS-800 in the order of CO 3 2-, SO 4 2-, NO 3- and Cl-. Based on experimental data to date, MVS-800 is an environmentally friendly adsorbent for recycling waste resources and is considered to be an adsorbent with high adsorption capacity for removing phosphates from aqueous solutions. This paper combines the advantages of gray predictor and AI fuzzy. The gray predictor can be used to predict whether the bear point exceeds the allowable deviation range, and then perform appropriate control corrections to accelerate the bear point to return to the boundary layer and achieve.
Key Words
adsorption; AI fuzzy grey; algorithmic calculations; calcination; thermal activation
Address
ZY Chen, Yahui Meng and ZY Gu: Guangdong University of Petrochem Technol, Sch Sci, Maoming, Guangdong, China
Huakun Wu: School of Computer Science, Guangdong Polytechnic Normal University, Guangzhou, Guangdong, China
Timothy Chen: Division of Eng App Sci, Caltech, CA 91125, U.S.A.
- A new viewpoint of lime/mineral dissolved solution for removal of phosphorus and the corresponding mechanism in wastewater C.C. Hung, T. Nguyễn, C.Y. Hsieh and M. Nasir
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Abstract; Full Text (1731K) . | pages 117-130. | DOI: 10.12989/mwt.2024.15.3.117 |
Abstract
The possibility of using lime/mineral solvent solutions has been investigated to effectively remove T-P from wastewater. The lime solvent solution showed an initial T-P removal efficiency of about 90% compared to the less efficient mineral solvent solution removal. High pH and dissolved Ca2+ can form hydroxyapatite minerals (Ca5(PO4)3(OH) or Ca10(PO4)6(OH)2 and can also remove SS and COD from wastewater. Feldspar dissolution solution can be reused twice because the Ca limited sample content provided, but further research is needed to discover other influencing parameters that control the T-P removal efficiency in real wastewater. Because it plays an important role of alkalinity in T-P removal, the success rate is limited. In practical applications, it is obtained according to the pH value wastewater in the environment. The results obtained in this study can highlight new insights on the use of limestone/dissolved mineral solutions to control T-P in wastewater, instead of directly using commercial chemical agents that can produce large amounts of unreacted chemical sludge.
Key Words
artificial intelligence tool; assessment; deep learning; sustainability; water resource
Address
C.C. Hung: Faculty of National Hsin Hua Senior High School, Tainan, Taiwan
T. Nguyễn and M. Nasir: Ha Tinh University, Dai Nai Ward, Ha Tinh City, Vietnam
C.Y. Hsieh: National Pingtung University Education School, No.4-18, Minsheng Rd., Pingtung City, Pingtung County 900391, Taiwan
- Fabrication of carboxymethyl functionalized Euryale ferox starch-based hydrogel for efficient removal of methylene blue Xue-Li Liu, Zhong-Zhu Hu, Ya-Li Sun and Chun-Feng Zhu
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Abstract; Full Text (1442K) . | pages 131-137. | DOI: 10.12989/mwt.2024.15.3.131 |
Abstract
Euryale ferox Salisb. is an important plant resource and valuable tonic in traditional Chinese medicine. The seed of Euryale ferox Salisb. is rich in starch. There are few reports of modification and functional properties of Euryale ferox starch. In present study, the Euryale ferox starch was extracted, carboxymethyl etherified starches were synthesized, the starch-based hydrogels were prepared, and adsorptive properties were investigated. The results of investigation showed that carboxymethyl etherified Euryale ferox starch-based adsorbent has the potential for methylene blue removal. Therefore, Euryale ferox starch has an appealing application prospect in adsorption for scavenging dyes from real complex waste liquid.
Key Words
adsorption application; chemical modification; Euryale ferox starch
Address
Xue-Li Liu, Zhong-Zhu Hu and Ya-Li Sun: College of Material and Chemical Engineering, Chuzhou University, Anhui 239012, China
Chun-Feng Zhu: Department of Pharmacy, Lu'an Hospital of Traditional Chinese Medicine, 237000, China
- Tuning the surface charge of mixed matrix membranes using novel chemistry Priyanka Mistry and C.N. Murthy
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Abstract; Full Text (1957K) . | pages 139-152. | DOI: 10.12989/mwt.2024.15.3.139 |
Abstract
Mixed matrix membranes have gained significant recognition in the wastewater treatment industry for their effectiveness in removing dyes, proteins, and heavy metals from water sources. Researchers have developed an innovative technique to enhance properties of these membranes by incorporating amine-functionalized carbon nanotubes into the polymer matrix. This approach introduces amine functional groups onto the membrane surface, which are then modified with trimesoyl chloride and cyanuric chloride. The modified membranes are characterized by XPS to confirm successful bonding of amines with the trimesoyl chloride and cyanuric chloride. The surface charge of the modified membrane also plays a role in the modification process; the membrane modified with trimesoyl chloride has a negative surface charge, while the one modified with cyanuric chloride has a more positive charge. At the same acidic pH, the positive or negative charge of the mixed matrix membranes assists in enhancing the rejection of heavy metals. This results in improved antifouling properties for both modified membranes. The heavy metal rejection for all modified membranes is higher than for unmodified membranes, due to both adsorption and complexation abilities of the functional groups on the membrane surface with heavy metal ions. As the membrane surface functionalities increase through modification, the separation due to complexation also increases. The bulk morphology of the membrane remains unchanged, while roughness slightly increases due to the surface treatment.
Key Words
antifouling property; bulk morphology; heavy metal rejection; mixed matrix membrane; surface charge
Address
Priyanka Mistry and C.N. Murthy: Macromolecular Materials Laboratory, Applied Chemistry Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat, India, 390001