Comparative Approach for Desalination of Brackish Water Using low pressure Nanofiltration membranes

Y. Mogheir¹, A. A. Abuhabib², A. Hasouna³, F. Shehab³ & S. A. Shaat³

¹⁾Environmental engineering dept., faculty of engineering, Islamic University of Gaza (IUG), Palestine, email: ymogheir@iugaza.edu.ps (Corresponding Author)

²⁾Environmental engineering dept., faculty of engineering, Islamic University of Gaza (IUG), Palestine, email:  azz200@hotmail.com

³⁾ Graduates of Environmental Eng Dept., IUG, Palestine, email: deep-emotion12@hotmail.com

Corresponding author Email: mailto:ymogheir@iugaza.edu.ps

Accepted 30 January 2013

Abstract

Nanofiltration membranes were tested using a widely common lab scale dead-end filtration system. Two commercial NF membranes, denoted as NF1 and NF2 were tested on pressure range (6-12) bars. The water samples used were real samples collected from BaniSuhaila well in Khan Yuonis as a representative ground water sample in Gaza strip, Palestine. The tested parameters were: Salt rejection (TDS), Nitrate removal(NO₃), Flux rate (L/m².hr), permeability (L/m².hr.bar) and Flux recovery rate. Following our lab work results, we may conclud that Nanofiltration membranes for desalting water are potentially suitable for brackish desalination in Gaza Strip due to: reasonable salt rejection, (up to 51%) for NF1 membrane at relatively low operating pressure of 12 bar attributing to energy consumption reduction as well as cost effective compared to the current used technology of RO membranes. Therefore, NF technology can be considered as standalone technology for brackish desalination in Gaza. Such advantage may also attribute to desalination trends developing in Gaza Strip. Reasonable flux rate with lower salt rejection were obtained for NF2. This may allow this membrane to be applied as pre-treatment process for RO membranes used in desalination plants in Gaza Strip attributing to scaling reduction and increasing of desalination efficiency. A relationship were build according to result between pressure and flux rate indicating that 2 bar increasing of pressure led to increase the flux by (25-39) percent on NF2 membrane and (21-39) percent on NF1 membrane using real samples, that will help the operator to efficiently operate desalination system using this technique.

Keywords: Desalination, Brackish Water, Low pressure Nanofiltration membranes.