Impact of Natural Organic Matter on Floc Size and Structure Effects in Membrane Filtration†

2005 ◽  
Vol 39 (17) ◽  
pp. 6477-6486 ◽  
Author(s):  
Sangyun A. Lee ◽  
Anthony G. Fane ◽  
T. David Waite
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Filtration ◽  
Floc Size ◽  
Size And Structure

Coagulation/flocculation/ultrafiltration for natural organic matter removal in drinking water production

2004 ◽  
Vol 4 (5-6) ◽  
pp. 215-222 ◽  
Author(s):  
A.R. Costa ◽  
M.N. de Pinho
Keyword(s):  
Drinking Water ◽  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Membrane Surface ◽  
Water Production ◽  
Cellulose Acetate Membranes ◽  
Wide Range ◽  
Drinking Water Production

Membrane fouling by natural organic matter (NOM), namely by humic substances (HS), is a major problem in water treatment for drinking water production using membrane processes. Membrane fouling is dependent on membrane morphology like pore size and on water characteristics namely NOM nature. This work addresses the evaluation of the efficiency of ultrafiltration (UF) and Coagulation/Flocculation/UF performance in terms of permeation fluxes and HS removal, of the water from Tagus River (Valada). The operation of coagulation with chitosan was evaluated as a pretreatment for minimization of membrane fouling. UF experiments were carried out in flat cells of 13.2×10−4 m2 of membrane surface area and at transmembrane pressures from 1 to 4 bar. Five cellulose acetate membranes were laboratory made to cover a wide range of molecular weight cut-off (MWCO): 2,300, 11,000, 28,000, 60,000 and 75,000 Da. Severe fouling is observed for the membranes with the highest cut-off. In the permeation experiments of raw water, coagulation prior to membrane filtration led to a significant improvement of the permeation performance of the membranes with the highest MWCO due to the particles and colloidal matter removal.

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.

Coupling effect of 17β-estradiol and natural organic matter on the performance of a PAC adsorption/membrane filtration hybrid system

Desalination ◽  
2009 ◽  
Vol 237 (1-3) ◽  
pp. 392-399 ◽  
Author(s):  
Kah-Young Song ◽  
Pyung-Kyu Park ◽  
Jae-Hyuk Kim ◽  
Chung-Hak Lee ◽  
Sangho Lee
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Hybrid System ◽  
Membrane Filtration ◽  
Coupling Effect ◽  
17Β Estradiol

scholarly journals NOM removal technologies – Norwegian experiences

2010 ◽  
Vol 3 (1) ◽  
pp. 1-9 ◽  
Author(s):  
H. Ødegaard ◽  
S. Østerhus ◽  
E. Melin ◽  
B. Eikebrokk
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Humic Substances ◽  
Natural Organic Matter ◽  
Membrane Filtration ◽  
Granular Media ◽  
Physical Adsorption ◽  
Nanofiltration Membranes ◽  
Removal Technologies ◽  
Molecular Sieving

Abstract. The paper gives an overview of the methods for removal of natural organic matter (NOM) in water, particularly humic substances (HS), with focus on the Norwegian experiences. It is demonstrated that humic substances may be removed by a variety of methods, such as; molecular sieving through nanofiltration membranes, coagulation with subsequent floc separation (including granular media or membrane filtration), oxidation followed by biofiltration and sorption processes including chemisorption (ion exchange) and physical adsorption (activated carbon). All these processes are in use in Norway and the paper gives an overview of the operational experiences.

Identification and control of fouling of low-pressure (MF and UF) membranes by drinking-water natural organic matter

2003 ◽  
Vol 3 (5-6) ◽  
pp. 217-222 ◽  
Author(s):  
N. Lee ◽  
G. Amy ◽  
H. Habarou ◽  
J.C. Schrotter
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Filtration ◽  
Gel Formation ◽  
Flux Decline ◽  
Organic Fouling ◽  
Pore Blockage ◽  
Uf Membranes ◽  
And Control ◽  
Filtration Flux

Natural organic matter (NOM) is responsible for organic fouling during membrane filtration. Flux decline can be affected by the characteristics of the NOM and its interaction with membranes and their associated properties. The results showed that serious flux decline observed for MF membranes may be caused by pore blockage associated with large (macromolecular) hydrophilic molecules. In the case of UF membranes, flux decline may be caused by sequential or simultaneous processes such as cake/gel formation with large (macromolecular) molecules and pore blockage with relatively smaller molecules during filtration. The flux decline tests with representative macromolecules showed that fouling was affected more by the physical characteristics (e.g. size and structure (shape)) of foulants than the characteristics (e.g. hydrophilicity) of foulants.

Natural Organic Matter (NOM) Transformations and their Effects on Water Treatment Process: A Contemporary Review

2021 ◽  
Vol 15 ◽  
Author(s):  
Manoj Kumar Karnena ◽  
Madhavi Konni ◽  
Bhavya Kavitha Dwarapureddi ◽  
Vara Saritha
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Natural Organic Matter ◽  
Membrane Filtration ◽  
Treatment Process ◽  
Climatic Conditions ◽  
Water And Wastewater Treatment ◽  
Water Treatment Process ◽  
Treatment Facilities ◽  
Water And Wastewater

Abstract: One of the several significant concerns related to water treatment plants is the transformation of natural organic matter (NOM) concerning quality and quantity due to the changing climatic conditions. The NOM consists of heterogeneous functionalized groups. Phenolic and carboxyl groups are the dominant groups that are pH-dependent and show a stronger affinity towards the metals. Properties of natural organic matter and trace elements govern the binding kinetics, influencing cations' binding to functionalized groups at lower pH. The water treatment process mechanisms like adsorption, coagulation, membrane filtration, and ion exchange efficiencies are sturdily influenced by the presence of NOM with cations and by the natural organic matter alone. The complexation among the natural organic matter and coagulants enhances the removal of NOM from the coagulation processes. The current review illustrates detailed interactions between natural organic matter and the potential impacts of cations on NOM in the water and wastewater treatment facilities.

The fouling of ultrafiltration membranes by natural organic matter after chemical coagulation treatment with different initial mixing conditions

2006 ◽  
Vol 6 (4) ◽  
pp. 117-124 ◽  
Author(s):  
H.C. Kim ◽  
J.H. Hong ◽  
S. Lee
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Membrane Filtration ◽  
Mixing Conditions ◽  
Mechanical Mixing ◽  
Chemical Coagulation ◽  
Flux Decline ◽  
Hydrophobic Fraction ◽  
Hydrophilic Membranes

The flux decline in the UF membrane filtration of water pretreated by chemical coagulation using different initial mixing conditions were compared and the influence of natural organic matter (NOM) on the fouling of membranes was investigated. It was suggested that organic matter in the molecular weight ranges 300–2,000 and 20,000–40,000 Daltons were mainly responsible for the fouling. The fouling was greater for hydrophobic than hydrophilic membranes. ATR-FTIR analysis of the fouled hydrophobic membranes indicated that aliphatic amide and alcoholic compounds as well as polysaccharides contributed to significant membrane fouling. These adsorptive foulants are considered as neutral fractions present in hydrophobic and hydrophilic NOM components. In the case of similar hydrophilic fractions, water precoagulated with a high hydrophobic content resulted in greater flux decline, which was presumed to be due to the organic matter with neutral properties contained within the hydrophobic fraction. The relative concentrations of each NOM fraction in coagulated water are important. Mechanical mixing for chemical coagulation, with a backmixing-type, rather than pump diffusion mixing, with an in-line type, is likely to be more effective at reducing the fouling caused by NOM.

scholarly journals NOM removal technologies – Norwegian experiences

2009 ◽  
Vol 2 (2) ◽  
pp. 161-187 ◽  
Author(s):  
H. Ødegaard ◽  
S. Østerhus ◽  
E. Melin ◽  
B. Eikebrokk
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Humic Substances ◽  
Natural Organic Matter ◽  
Membrane Filtration ◽  
Granular Media ◽  
Physical Adsorption ◽  
Nanofiltration Membranes ◽  
Removal Technologies ◽  
Molecular Sieving

Abstract. The paper gives an overview of the methods for removal of natural organic matter (NOM), particularly humic substances (HS), in water with focus on the Norwegian experiences. It is demonstrated that humic substances may be removed by a variety of methods, such as; molecular sieving through nanofiltration membranes, coagulation with subsequent floc separation (including granular media or membrane filtration), oxidation followed by biofiltration and sorption processes including chemisorption (ion exchange) and physical adsorption (activated carbon). All these processes are in use in Norway and the paper gives an overview of the operational experiences.

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