Abstract
This study aimed to discover the potential application of the draw solution system based on trisodium α-DL- alanine diacetate (MGDA draw solution) in forward osmosis (FO) desalination systems through the optimization of some important operational parameters, the investigation of fouling behaviours after long-term operation and the efficiency of mitigating strategies, and the analytical of some key quality properties of the produced freshwater. Optimization results suggested that in the investigated range, inlet temperature was the main operational parameters that influence the osmosis performance of the MGDA draw solution. Under the optimized operational parameters (inlet pressure difference = 0.4 bar on the feed side, inlet temperature = 30 °C, and feed side inlet flow rate = 250 mL•min−1), the osmosis performance obtained were Jw = 9.996 ± 0.192 LMH and Rds = 0.3580 ± 0.0020 g•L−1. Furthermore, experimental results also emphasized the advantages of MGDA solution, which were low tendency of membrane fouling and the relatively ease of membrane cleaning. Finally, experiments on real brackish water samples confirmed the potential application of the MGDA draw solution in FO desalination systems, with the produced freshwater meeting key requirements as recommended in the National Technical Regulation QCVN 01-1:2018/BYT.
Key Words
Box–Behnken optimization; forward osmosis; long-term operation; membrane fouling; water quality
Address
Tao M. Hoang, Tung N. Nguyen, Minh Q. Bui, Dat T. Nguyen, and Anh L.T. Hoang: Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, 10072, Vietnam/ Center for High Technology Research and Development, Vietnam Academy of Science and Technology, Hanoi, 10072, Vietnam
Hung T. Trinh, Minh N. Truong and Giang H. Do: Center for High Technology Research and Development, Vietnam Academy of Science and Technology, Hanoi, 10072, Vietnam
Abstract
Heated Aluminum Oxide Particles (HAOPs) have emerged as a promising class of engineered adsorbents with unique physicochemical properties suited for water purification. Their ability to effectively remove a range of contaminants positions them as valuable materials in advancing water treatment technologies. This review summarizes current research on HAOPs covering their synthesis, chemistry, adsorption mechanisms, applications, comparative analysis, environmental aspects, and future research directions. The HAOPs were synthesized by neutralizing aluminum sulfate hydrate with sodium hydroxide to form aluminum hydroxide precipitates, which were then heated at 110°C for 24 hours. They have a well-organized microcrystalline structure with abundant surface hydroxyl groups, contributing to high adsorption efficiency, and demonstrate significant potential in removing natural organic matter, phosphorus, and uranium from water sources. Compared to other adsorbents such as powdered activated carbon and iron oxide particles, HAOPs offer improved contaminant removal and fouling mitigation. Environmentally, their moderate-temperature synthesis reduces energy consumption and production costs. Effective regeneration extends material life and reduces waste, but proper disposal and management of spent HAOPs are crucial to avoid secondary pollution. Comprehensive life-cycle cost assessments and advanced regeneration methods are needed to improve economic feasibility and sustainability. Future research should focus on developing HAOP composites and exploring sustainable disposal and regeneration options to optimize their application in water treatment systems.
Address
Ladawan Mee-ngern, Muhammad Yaqub and Wontae Lee: Department of Environmental Engineering, Kumoh National Institute of Technology, 61 Daehak-ro, Gumi, Gyeongsangbuk-do 39177, Republic of Korea
Abstract
This study investigated the stability and effectiveness of biological nitrogen removal from high-strength reverse osmosis (RO) concentrate using a sequencing batch reactor (SBR) process. We examined the influence of varying temperatures (5–25°C) and carbon-to-nitrogen (C/N) ratios (2:1–5:1), utilizing methanol as an external carbon source. The results demonstrated consistently high total nitrogen removal efficiencies (91–97%) at temperatures between 15°C and 25°C, regardless of the C/N ratio. Nitrification exhibited robust performance, achieving approximately 97% efficiency across this temperature range, even at lower C/N ratios. Denitrification efficiency, however, showed a notable increase with higher C/N ratios, reaching 99.38% and 99.07% at C/N ratios of 4:1 and 5:1, respectively. At 5°C, significant inhibition of microbial activity was observed, causing nitrogen removal efficiency to drop below 40% across all C/N ratios, highlighting the importance of temperature control in practical applications. Chemical oxygen demand (COD) levels remained relatively stable (40–60 mg/L) within the 10°C to 25°C range, but an increase in CODcr release at 5°C suggested organic matter accumulation due to reduced biodegradation. In conclusion, the SBR process proved effective for nitrogen removal from RO concentrate under moderate temperature conditions (&ge10°C), though supplementary treatment may be necessary for complete organic matter removal, especially at low temperatures. These findings contribute valuable insights for optimizing biological treatment strategies for RO concentrate reuse or discharge.
Address
Seong-Min Cho, Jin-San Lee, Cheol-Gyu Park, Yun Chul Woo and Han-Seung Kim: Department of Environmental Engineering and Energy, Myongji University, 116 Myongjiro, Cheoin-gu, Yongin-si, Gyeonggi-do 17058, Republic of Korea
Sun-A An: K-Water Institute, 125, 1689beon-gil, Yuseong-daero, Yuseong-gu, Daejeon, 34045, Republic of Korea
Abstract
Biomass waste treatment via carbonization has drawn considerable attention due to its applications such as a solid fuel and an adsorbents for wastewater. The characteristics of carbonized products can be influenced by various factors including selection of biomass waste, carbonization temperature, duration, and pretreatment technologies adopted during the process. Indeed, the conversion of biomass waste into the carbonized product presents the sustainable approach to deal with increasing biomass waste responding to the growing energy demands and the need for emerging contaminant removal. This paper provides a brief review of current re-search trends and advancements in biomass carbonization, along with proposed carbonization system design for a sustainable approach. Emphasis is placed on the value-added products through carbonized biomass waste, highlighting its significance towards a sustainable society along with the carbon-neutral system.
Key Words
adsorbent; biomass; carbonization; energy; solid fuel
Address
Jiseok Hong, Changwon Chae and Ijung Kim: Department of Civil and Environmental Engineering, Hongik University, 94 Wausan-ro, Mapo-gu, Seoul, Republic of Korea
Abstract
The quality of hydration is the most important factor that influences the performance, recovery process and wellness of an athlete. The typical membrane-based water recovery systems of modern sports complexes must be able to remove harmful compounds, preferably retaining advantageous electrolytes. With a direct focus in the implications of athlete hydration, this broad overview examines how the incorporation of nanoparticles (NPs; specifically, graphene oxide (GO), silver (Ag), and titanium dioxide (TiO2)) can transform and alter mechanical/functional behavior of these membranes. We observe that NP-reinforced membranes have better mechanical strength, and antifouling capability, resulting in more consistent and effective system performance. Importantly, the nanocomposite membranes can be strategically engineered to achieve selective permeability thus allowing specifically tailored rotavirus pathogen and organic purity rejection but necessitating key electrolyte passage as magnesium and potassium. This leads to the production of naturally fortified water on a consistent basis in order to promote the best possible rehydration without necessarily relying on artificial supplements. It is concluded that nanotechnology brings a paradigm shift in the field of sports water treatment beyond simple purification to the proactive optimization of the hydration quality so as to match to the exact specific physiology of the athlete and, therefore, directly leads to the maximization of performance and safety.
Key Words
concrete pipeline; differential quadrature method; dynamic response; internal and external fluid; tabas earthquake
Address
Ying Meng: Graduate School of Sports Science, Dongshin University, Naju-si 58245, Jeollanamdo, Republic of Korea
Zhubo Xu: Physical Education Department, Anhui University of Finance and Economics, Bengbu 233041, Anhui, China
A. Zamani Nouri: Department of Civil Engineering, ShQ. C., Islamic Azad University, Shahr-e-Qods, Iran
