Influence of floc size and structure on membrane fouling in coagulation–ultrafiltration hybrid process—The role of Al13 species

2011 ◽  
Vol 193 ◽  
pp. 249-256 ◽  
Author(s):  
Weiying Xu ◽  
Baoyu Gao ◽  
Ranran Mao ◽  
Qinyan Yue
RSC Advances ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 163-173 ◽  
Author(s):  
Jun Nan ◽  
Meng Yao ◽  
Qinggui Li ◽  
Dan Zhan ◽  
Ting Chen ◽  
...  

The impact of shear conditions during coagulation on the ultrafiltration permeate flux in a coagulation–ultrafiltration (C–UF) process was investigated.


2014 ◽  
Vol 926-930 ◽  
pp. 158-161
Author(s):  
Wan You Zhang ◽  
Sheng Chao Ji ◽  
Hai Feng Zhang ◽  
Xi Xin Zhang

Membrane bioreactor (MBR) has developed rapidly in recent years; however, the membrane fouling problems are affecting its further widespread application. This paper discusses the role of metal ions in the mixture in the mechanism; also on the high-priced metal ions coexist in the mixture when the effects of biological flocculation process; finally, the direction of future research in this area are summarized.


2013 ◽  
Vol 10 (80) ◽  
pp. 20120987 ◽  
Author(s):  
Mirjana Dimitrijev Dwyer ◽  
Lizhong He ◽  
Michael James ◽  
Andrew Nelson ◽  
Anton P. J. Middelberg

Mixtures of a large, structured protein with a smaller, unstructured component are inherently complex and hard to characterize at interfaces, leading to difficulties in understanding their interfacial behaviours and, therefore, formulation optimization. Here, we investigated interfacial properties of such a mixed system. Simplicity was achieved using designed sequences in which chemical differences had been eliminated to isolate the effect of molecular size and structure, namely a short unstructured peptide (DAMP1) and its longer structured protein concatamer (DAMP4). Interfacial tension measurements suggested that the size and bulk structuring of the larger molecule led to much slower adsorption kinetics. Neutron reflectometry at equilibrium revealed that both molecules adsorbed as a monolayer to the air–water interface (indicating unfolding of DAMP4 to give a chain of four connected DAMP1 molecules), with a concentration ratio equal to that in the bulk. This suggests the overall free energy of adsorption is equal despite differences in size and bulk structure. At small interfacial extensional strains, only molecule packing influenced the stress response. At larger strains, the effect of size became apparent, with DAMP4 registering a higher stress response and interfacial elasticity. When both components were present at the interface, most stress-dissipating movement was achieved by DAMP1. This work thus provides insights into the role of proteins' molecular size and structure on their interfacial properties, and the designed sequences introduced here can serve as effective tools for interfacial studies of proteins and polymers.


2019 ◽  
Vol 5 (12) ◽  
pp. 2242-2250
Author(s):  
Xue Shen ◽  
Baoyu Gao ◽  
Kangying Guo ◽  
Qinyan Yue

Coagulation prior to the ultrafiltration (UF) process was implemented to improve natural organic matter (NOM) removal and membrane permeability.


2004 ◽  
Vol 50 (12) ◽  
pp. 279-285 ◽  
Author(s):  
J.H. Kweon ◽  
D.F. Lawler

The biggest impediment for applying membrane processes is fouling that comes from mass flux (such as particle and organic matter) to the membrane surface and its pores. Numerous research articles have indicated that either particles or natural organic matter (NOM) has been the most detrimental foulant. Therefore, the role of particles in membrane fouling was investigated with two synthetic waters (having either particles alone or particles with simple organic matter) and a natural water. Membrane fouling was evaluated with flux decline behavior and direct images from scanning electron microscopy. The results showed that the combined fouling by kaolin and dextran (a simple organic compound selected as a surrogate for NOM) showed no difference from the fouling with only the organic matter. The similarity might stem from the fact that dextran (i.e., polysaccharide) has no ability to be adsorbed on the clay material, so that the polysaccharide behaves the same with respect to the membrane with or without clay material being present. In contrast to kaolin, the natural particles showed a dramatic effect on membrane fouling.


Sign in / Sign up

Export Citation Format

Share Document