OBJECTIVES: The performance of spiral-wound nanofiltration (NF) and ultrafiltration (UF) membranes was investigated in terms of natural organic matter (NOM) rejection and associated NOM fouling. The study objectives focused on • demonstrating the effects of both hydrophobic and electrostatic interactions between NOM components and the membrane surface • determining influential factors (water qu...

background: chromium (cr) is the most important element used to plate other metals and electroplating factories are still consid­ered to be the most important industries which pollute the environment to this metal. this paper describes a study con­ducted to determine the efficiency of reverse-osmosis (ro) as a membrane technique for removal of cr from wastewater sam­ples synthetically prepared ...

In this work, performance data from a small-scale reverse osmosis (RO) plant based on seawater FilmTec spiral wound RO membranes for different periods of operation are presented and analyzed. A prototype RO set-up with a 2,200 L/d capacity was installed and operated at Urla Bay which was located in Izmir, Turkey. This study typically investigates RO performance in terms ...

Spacers are used in spiral wound and plate and frame membrane modules to create flow channels between adjacent membrane layers and mix fluid within the flow channel. Flow through the spacer has a significant beneficial impact on mixing and resulting mass transfer rates but is accompanied by an undesirable increase in pressure drop. Computational Fluid Dynamics (CFD) is a common tool used to eva...

A systematic design strategy for spiral-wound gas separation systems is studied using a recently proposed algebraic permeator model (Qi and Henson, Approximate modeling of spiral-wound gas permeators, J. Membrane Sci. 121 (1996) 11–24). Nonlinear programming (NLP) is used to determine operating conditions which satisfy the separation requirements while minimizing the annual process cost. The de...

Multi-objective optimization using genetic algorithm (GA) is carried out for the desalination of brackish and sea water using spiral wound or tubular modules. A few sample optimization problems involving two and three objective functions are solved, both for the operation of an existing plant (which is almost trivial), as well as, for the design of new plants (associated with a higher degree of...

in this research, the chloroform (chcl3) removal effectiveness of two water treatment systems including membrane technology and granular activated carbon (gac) adsorption were studied. two bench-scales were designed and set up: 1) nanofiltration (nf) spiral-wound modules and 2) gac adsorption column. chloroform was considered as trihalomethanes (thms) basic indicator compound. the inlet and out...

We have tested the applicability of the global modal approach in the density wave theory of spiral structure for a sample of six spiral galaxies: NGC 488, NGC 628, NGC 1566, NGC 2985, NGC 3938 and NGC 6503. The galaxies demonstrate a variety of spiral patterns from the regular open and tightly wound spiral patterns to a multi-armed spiral structure. Using the observed radial distributions of th...

objective- this study aimed to evaluate the feasibility of using platelet rich fibrin membrane as a novel on-lay patching biomaterial in canine esophagotomy and its effects on esophageal wound healing. design- experimental study. animals- eight adult mixed breed dogs of both sexes equally allocated to control and treatment groups. procedures- longitudinal incisions measuring 3 cm were made in t...