scholarly journals Effective natural organic matter removal in pond water by carbon nanotube membrane with flocculation/adsorption

2017 ◽  
Vol 17 (4) ◽  
pp. 1080-1087
Author(s):  
Jieun Lee ◽  
Saravanamuth Vigneswaran ◽  
Yongshun Zhang ◽  
Ramireddy S. P. Raj Reddy ◽  
Zongwen Liu
Keyword(s):  
Organic Matter ◽  
Carbon Nanotube ◽  
Water Treatment ◽  
Natural Organic Matter ◽  
Removal Rate ◽  
Pond Water ◽  
Aluminium Chloride ◽  
Superior Performance ◽  
Permeate Flux ◽  
Flux Decline

A carbon nanotube (CNT) ultrafiltration (UF) membrane was applied to natural organic matter (NOM) removal in pond water treatment. The source water was pretreated by flocculation and/or adsorption prior to the UF process to alleviate permeate flux decline and improve NOM removal efficiency. The performance of a commercial polyethersulfone (PES) UF membrane was compared to evaluate that of the CNT membrane. The CNT membrane outperformed the PES-UF membrane. The permeate flux, total organic carbon and humic acid (HA) removal rate of the CNT membrane was observed to be 230 LMH/bar, 60%, and 80% when 30 mg/L poly aluminium chloride (PACI) flocculation was applied. This highlights that the permeate flux was three times higher with slightly higher rejection efficiency than the PES-UF membrane. In particular, severe permeate flux decline was completely overcome by the CNT membrane with 30 mg/L PACI coagulation. For powder activated carbon (PAC) adsorption, even though there was a severe permeate flux decline in the CNT membrane, almost complete HA removal (98%) was achieved when 0.5 g/L PAC adsorption was coupled. Based on the superior performance of the CNT membrane with pretreatment, the CNT membrane is suggested to be a robust system for a high concentration of organic matter pond water treatment without membrane flux decline.

Influence of operating conditions on performance of ceramic membrane used for water treatment

2014 ◽  
Vol 68 (2) ◽  
Author(s):  
Agnieszka Urbanowska ◽  
Małgorzata Kabsch-Korbutowicz
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Flow Velocity ◽  
Natural Organic Matter ◽  
Ceramic Membrane ◽  
Operating Time ◽  
Ceramic Membranes ◽  
Operating Conditions ◽  
Human Consumption ◽  
Permeate Flux

AbstractThe removal of natural organic matter (NOM) is a critical aspect of potable water treatment because NOM compounds are precursors of harmful disinfection by-products, hence should be removed from water intended for human consumption. Ultrafiltration using ceramic membranes can be a suitable process for removal of natural substances. Previously reported experiments were dedicated to evaluating the suitability of ultrafiltration through ceramic membrane for water treatment with a focus on the separation of natural organic matter. The effects of the membrane operating time and linear flow velocity on transport and separation properties were also examined. The experiments, using a 7-channel 300 kDa MWCO ceramic membrane, were carried out with model solutions and surface water at trans-membrane pressure of 0.2–0.5 MPa. The results revealed that a loose UF ceramic membrane can successfully eliminate natural organic matter from water. The permeability of the membrane was strongly affected by the composition of the feed stream, i.e. the permeate flux decreased with an increase in the NOM concentration. The permeate flux also decreased over the period of the operation, while this parameter did not influence the effectiveness of separation, i.e. the removal of NOM. It was observed that the increased cross-flow velocity resulted in the decrease in the membrane-fouling intensity and slightly improved the retention of contaminants.

Preparation of engineered carbon nanotube materials and its application in water treatment for removal of hydrophobic natural organic matter (NOM)

2016 ◽  
Vol 57 (52) ◽  
pp. 24855-24866 ◽  
Author(s):  
Saeed Skandari ◽  
Ali Torabian ◽  
Gholamreza Nabi Bidhendi ◽  
Majid Baghdadi ◽  
Behnoush Aminzadeh
Keyword(s):  
Organic Matter ◽  
Carbon Nanotube ◽  
Water Treatment ◽  
Natural Organic Matter

Development of an integrated iron oxide adsorption/membrane separation system for water treatment

2002 ◽  
Vol 2 (5-6) ◽  
pp. 293-300 ◽  
Author(s):  
K.-W. Lee ◽  
K.-H. Choo ◽  
S.-J. Choi ◽  
K. Yamamoto
Keyword(s):  
Organic Matter ◽  
Iron Oxide ◽  
Natural Organic Matter ◽  
Oxide Particle ◽  
Iron Oxide Particle ◽  
Drinking Water Source ◽  
Raw Water ◽  
Permeate Flux ◽  
Flux Decline ◽  
Dissolved Matter

The performance of an integrated iron oxide particle (IOPs) adsorption and ultrafiltration (UF) process was investigated in terms of natural organic matter removal and membrane permeability during treatment of a drinking water source. Throughout the fractionation of raw water and subsequent UF of fractioned portions, the significance of each component in raw water affecting flux decline during IOP-UF was evaluated. Natural organic matter (NOM) removal efficiencies for the IOP-UF system increased markedly as a substantial amount of IOPs was added into suspension, without any negative effect on permeate flux. During IOP-UF testings, there was no difference in NOM removal regardless of the locations of IOPs whether they were either in suspension or deposited on the UF membrane, but significant initial flux reduction occurred with the formation of a precoat (attached) layer. However, all IOPs in suspension and in the cake were effective in both removing NOM and preventing irreversible fouling as long as they were removed by backwashing. Dissolved matter obtained from filtration through a 0.45 μm filter was more responsible for flux decline in UF than larger colloids. Particularly, IOP-adsorbable dissolved matter accounted for 60% of total flux decline, confirming the attractiveness of IOP addition to UF.

Comparative Study of Ozone Alone and Catalytic Ozonation for Transformation of Natural Organic Matter in River Water

2011 ◽  
Vol 183-185 ◽  
pp. 1312-1316
Author(s):  
Gang Wen ◽  
Jun Ma ◽  
Xing Fang
Keyword(s):  
Molecular Weight ◽  
Organic Matter ◽  
Water Treatment ◽  
Comparative Study ◽  
River Water ◽  
Natural Organic Matter ◽  
Removal Rate ◽  
Catalytic Ozonation ◽  
Experimental Results ◽  
Promising Method

Ozone alone and catalytic ozonation of natural organic matter had been carried out in semibatch model reactor. The experimental results demonstrated that ozonation alone and catalytic ozonation are equivalent with minimization of natural organic matter(NOM), with the removal rate of TOC, UV254 about 7 % and 50 % respectively. But it is a promising method for changing the molecular weight and specially for enhancement of biodegradation. The AOC in river water was 233 ug L-1, which increase up to 325 ug L-1, 677 ug L-1, 633 ug L-1 in ozonation alone, catalytic ozonation (H2O2) and catalytic ozonation (ZnO) after 30 minutes reaction respectively. Through the research, it can be conclued that catalytic ozonation-BAC may be an promising way for water treatment.

Removal of natural organic matter at the Gunbower water treatment plant in northern Victoria, Australia

2015 ◽  
Vol 57 (20) ◽  
pp. 9061-9069
Author(s):  
Sanghyun Jeong ◽  
Tien Vinh Nguyen ◽  
Saravanamuthu Vigneswaran ◽  
Jaya Kandasamy ◽  
Dharma Dharmabalan
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Natural Organic Matter ◽  
Treatment Plant ◽  
Water Treatment Plant

scholarly journals Natural organic matter removal by ion exchange at different positions in the drinking water treatment lane

2013 ◽  
Vol 6 (1) ◽  
pp. 1-10 ◽  
Author(s):  
A. Grefte ◽  
M. Dignum ◽  
E. R. Cornelissen ◽  
L. C. Rietveld
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Organic Matter ◽  
Water Treatment ◽  
Organic Carbon ◽  
Natural Organic Matter ◽  
Drinking Water Treatment ◽  
Biological Stability ◽  
Sand Filtration ◽  
Slow Sand Filtration

Abstract. To guarantee a good water quality at the customers tap, natural organic matter (NOM) should be (partly) removed during drinking water treatment. The objective of this research was to improve the biological stability of the produced water by incorporating anion exchange (IEX) for NOM removal. Different placement positions of IEX in the treatment lane (IEX positioned before coagulation, before ozonation or after slow sand filtration) and two IEX configurations (MIEX® and fluidized IEX (FIX)) were compared on water quality as well as costs. For this purpose the pre-treatment plant at Loenderveen and production plant Weesperkarspel of Waternet were used as a case study. Both, MIEX® and FIX were able to remove NOM (mainly the HS fraction) to a high extent. NOM removal can be done efficiently before ozonation and after slow sand filtration. The biological stability, in terms of assimilable organic carbon, biofilm formation rate and dissolved organic carbon, was improved by incorporating IEX for NOM removal. The operational costs were assumed to be directly dependent of the NOM removal rate and determined the difference between the IEX positions. The total costs for IEX for the three positions were approximately equal (0.0631 € m−3), however the savings on following treatment processes caused a cost reduction for the IEX positions before coagulation and before ozonation compared to IEX positioned after slow sand filtration. IEX positioned before ozonation was most cost effective and improved the biological stability of the treated water.

scholarly journals Super-bridging Fibrous Materials for Water Treatment: Impacts on Removal of Plastic Particles, Phosphorus and Natural Organic Matter

2021 ◽  
Author(s):  
Mathieu Lapointe ◽  
Heidi Jahandideh ◽  
Jeffrey Farner ◽  
Nathalie Tufenkji
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Natural Organic Matter ◽  
Emerging Contaminants ◽  
Settling Tank ◽  
Process Unit ◽  
Fibrous Materials ◽  
Floc Size ◽  
Sludge Waste ◽  
Treatment Facilities

Aggregation combined with gravitational separation is the most commonly used method to treat water globally, but it carries a significant economic and environmental burden as the chemicals used in the process (e.g., coagulants) generate ~8 million tons of metal-based sludge waste annually. To simultaneously deal with the issues of process sustainability, cost, and efficiency, we developed materials reengineered from pristine or waste fibers to serve as super-bridging agents, adsorbents, and ballast media. This study shows that these sustainable fiber-based materials considerably increased the floc size (~6630 µm) compared to conventional physicochemical treatment using a coagulant and a flocculant (~520 µm). The fiber-based materials also reduced coagulant (up to 40%) and flocculant usage (up to 60%). Moreover, the unprecedented size of flocs produced using fiber-based materials (up to ~13 times larger compared to conventional treatment) enabled easy floc removal by screening, thereby eliminating the need for a settling tank, a large and costly process unit. Our results show that fiber-based materials can be effective solutions at removing classical (e.g., natural organic matter (NOM) and phosphorus) and emerging contaminants (e.g., microplastics and nanoplastics). Due to their large size (> 3000 µm), some Si-grafted and Fe-grafted fiber-based materials can be easily recovered from settled/screened sludge and reused multiple times for coagulation/flocculation. Our results also show that these materials could be used in synergy with coagulants and flocculants to improve settling in existing water treatment processes. Furthermore, these reusable materials combined with separation via screening could allow global water treatment facilities to reduce their capital and operating costs as well as their environmental footprint.

scholarly journals DEET Degradation by Titanium Dioxide–Zeolite Nanocomposites: Effects of Aggregation State, Water Chemistry, and Natural Organic Matter

2020 ◽  
Author(s):  
Tchemongo B. Berté ◽  
Anthony S. Chen ◽  
Riya A. Mathew ◽  
Sheyda Shakiba ◽  
Stacey M. Louie
Keyword(s):  
Titanium Dioxide ◽  
Organic Matter ◽  
Water Treatment ◽  
Water Chemistry ◽  
Natural Organic Matter ◽  
Titanium Dioxide Nanoparticles ◽  
Hard Water ◽  
Aggregation State ◽  
Byproduct Formation ◽  
Partial Dissociation

Immobilization of titanium dioxide nanoparticles (TiO<sub>2</sub> NPs) facilitates their removal and reuse in water treatment applications. Composite materials of electrostatically-bound TiO<sub>2</sub> NPs and zeolite particles have been proposed, but limited mechanistic studies are available on their performance in complex media. This study delineates the relative importance of homo- and heteroaggregation, water chemistry, and surface fouling by natural organic matter (NOM) on the photocatalytic degradation of diethyltoluamide (DEET) by TiO<sub>2</sub>-zeolite composites. Zeolite adsorbs a portion of the DEET, rendering it unavailable for degradation; corrections for this adsorption depletion allowed appropriate comparison of the reactivity of the composites to the NPs alone. The TiO<sub>2</sub>-zeolite composites showed enhanced DEET degradation in moderately hard water (MHW) compared to deionized water (DIW), likely attributable to the influence of HCO<sub>3</sub><sup>−</sup>, whereas a net decline in reactivity was observed for the TiO<sub>2</sub> NPs alone upon homoaggregation in MHW. The composites also better maintained reactivity in the presence of NOM in MHW, as removal of Ca<sup>2+</sup> onto the zeolite mitigated fouling of the TiO<sub>2</sub> surface by NOM. However, NOM induced partial dissociation of the composites. DEET byproduct formation, identified by quadrupole–time of flight (QTOF) mass spectrometry, was generally unaffected by the zeolite, while NOM fouling favored de-ethylation over hydroxylation products. Overall, the most significant factor influencing TiO<sub>2</sub> reactivity toward DEET was NOM adsorption, followed by homoaggregation, electrolytes (here, MHW versus DIW), and heteroaggregation. These findings can inform a better understanding of NP reactivity in engineered water treatment applications.

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