VNUHCM Journal of Earth Science and Environment

Developing a set of appropriate criteria on production technology and environmental treatment for steel product manufacturing facilities with hot dip zinc plating process in Ba Ria - Vung Tau Province

2025-06-18T13:34:30+07:00

Ba Ria - Vung Tau (BRVT) is a province with a lot of potential for industrial development and is prioritizing attracting investment in supporting industry development - an industry group that almost always needs the plating process to complete product improvement. However, in project investment approval, projects with production technology processes including the plating process will encounter barriers due to Decision No. 2214/QD-UBND dated August 16, 2016 of the People's Committee of BRVT province. Therefore, it is necessary to develop a set of appropriate criteria to evaluate production and waste treatment technology to have a basis for adjusting investment attraction criteria more appropriately for the above industry group. The study analyzed the current state of operations of steel product factories in the province, focusing on projects with galvanizing processes. Actual investigation and collection of detailed assessments of production technology and waste treatment technology at factories. Combined with the expert consultation method and Analytical Hierarchy Process method, the study has screened and proposed an appropriate set of criteria to evaluate production technology and environmental treatment at steel product manufacturing facilities. The hot-dip galvanizing process includes 04 groups of criteria with 11 specific criteria. Initially, the assessment was applied at 5 factories manufacturing and processing steel products. According to the evaluation results, the selected factories are all classified as having a fair and high level of suitability in production technology and waste treatment. This result shows that the factories pay great attention to production technology and environmental treatment. In addition, the study has proposed directions to adjust criteria for considering and attracting investment for industrial groups that use galvanizing in general and hot-dip galvanizing in particular in the province.

Performance comparison of conventional biological treatment process and membrane bioreactor treating common industrial effluent

2025-06-23T14:39:17+07:00

Industrial effluent is challenging for wastewater treatment plants due to its complexity, toxicity and variable composition This study aimed to evaluate the efficiency of industrial wastewater treatment after a primary sedimentation tank using lab-scale membrane bioreactor (MBR), and a full-scale anoxic/oxic process. The results showed that the treated water quality from both systems was similar and satisfied the national effluent standard (column B of QCVN 40-MT:2011/BTNMT). The removal rates of COD, TN, TP and color of activated sludge process in industrial zones were 234 ± 119, 16 ± 3, 0.3 ± 0.2, 100 ± 120 mg/L.day, respectively. The removal rates of COD, TN, TP, and color in MBR were 1.6, 1.3, 10.3, and 2.1 times higher than those in the A/O process, respectively. Although the A/O process in industrial zones performed well, the MBR system demonstrated higher removal rates, particularly for nutrient removal. Besides, MBR systems offer several advantages, including reduced excess sludge production and less space requirements compared to A/O process. In general, MBR offers a promising solution for industrial wastewater treatment, with strong potential for application in industrial zones.

Application of quantum geographic information system (QGIS) changes water quality index (WQI) according to seasons of Thi Tinh River

2025-07-03T16:59:55+07:00

Research on the application of geographic information system (QGIS) to assess seasonal water quality (WQI) changes of Thi Tinh river to provide a database to contribute additional data sources to support the management of surface water resources of Binh Duong province. The results of calculating the WQI (Water Quality Index) from water quality monitoring locations of the Thi Tinh river in the rainy and dry seasons for many years, the study used Quantum Geographic Information Systems (QGIS) to interpolate the WQI results, create maps to compare and evaluate CLN over space and time. Average WQI of the area from bordering Binh Phuoc province, Cam Xe stream, Phu Binh bridge (WQI = 75-97); area from Phu Binh bridge, Cau Quan stream, bridge on Ring Road 4 from (WQI =73-88); area from bridge on Ring Road 4 to Ong Co bridge, location flowing to Saigon River (WQI = 77-92). Water quality on Thi Tinh River in the rainy season is better than water quality in the dry season. Thi Tinh river water quality in 2023 and 2024 is better than in 2022, and water quality in all seasons in 2023 and 2024 tends to be stable and less variable than the same period in 2022. Research to establish a map The surface water quality interpolation map on the Thi Tinh River contributes additional data sources to support the surface water source of Binh Duong province.

Utilizing pineapple peel crosslinked chitosan as an eco-friendly biosorbent for heavy metal removal: A circular economy perspective

2025-07-04T17:24:38+07:00

This study fabricated chitosan beads obtained from pineapple peels as sustainable biosorbents for hexavalent chromium (Cr (VI)) extraction from water, thus supporting circular economy initiatives. Heavy metal pollution in water systems is a crucial environmental issue that has serious consequences for human health, aquatic ecosystems, and the overall environment. Heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), zinc (Zn), and copper (Cu) are particularly problematic since they are non-biodegradable, tend to bioaccumulate in organisms, and have the ability to impair cellular function, posing long-term ecological and public health problems. Two biosorbents, PPA (glutaraldehyde crosslinked) and PPB (citric acid crosslinked), were synthesized and investigated using SEM and FTIR to investigate the structural and functional changes caused by the crosslinking agents. While PPB included more carboxyl groups due to citric acid crosslinking, FTIR analysis confirmed the presence of functional groups required for Cr (VI) binding. With optimal Cr (VI) removal at pH 3.0, testing results revealed maximal adsorption capacities of 18.87 mg/g for PPA and 21.01 mg/g for PPB. Increased availability of functional groups and adsorption surface stability improve PPB performance. Adsorption isotherm analysis revealed that both biosorbents followed the Freundlich model, indicating a heterogeneous adsorption mechanism. Kinetic investigations identified pseudo-first-order chemisorption as the major mechanism. Thermodynamic investigation revealed negative Gibbs free energy values (∆G), confirming the spontaneous nature of Cr (VI) adsorption. With PPB showing improved performance, this study demonstrates the efficacy of chitosan beads generated from pineapple peels as a sustainable and low cost biosorbent for heavy metal cleanup. The findings emphasize the importance of crosslinking agents in improving biosorbent performance, giving valuable information for the development of efficient and cost-effective wastewater treatment methods aligned with sustainability and circular economy concepts.