Effect of air gap membrane distillation parameters on the removal of fluoride from synthetic water

Abstract

a b s t r a c tAs freshly available water around the world becomes scarcer, schemes to reuse and rectify contaminated water sources are becoming a necessity. The implementation of conventional treatment processes increases stress on existing infrastructure resources, requiring significant quantities of energy and/or chemicals, including pre-treatment processes and ongoing maintenance. An unconventional alternative to these processes is air-gap membrane distillation (AGMD), an emerging technology delivering excellent rejection of contaminants over a broad range of operating conditions. While showing great promise, the size of membrane distillation systems in existing literature is not readily scaled to industrial levels. In this paper, we present the results of our research in terms of permeate quality, rejection efficiency and scalability of a large laboratory scale AGMD system, with effective area of approximately 25 times larger than those presented in previous studies. This study found a large discrepancy in flux production when compared with small scale results, with experimental data analysed using normality and residual analysis tests. Statistical analysis of the AGMD process data provides insight into the key driving forces and interactions of feedwater temperature, concentration and flowrate on flux production. Results showed excellent rejection of contaminants (>98%) along with some fouling evident after approximately 25 h of operation.

Ultrasound-assisted membrane technologies for fouling control and performance improvement: A review

“…AGMD has many advantages, including cost efficiency [1], lower chemical demand [175], no feedwater pretreatment [40] and low membrane damage [176,177]. Moreover, AGMD is capable of separating all non-volatile matter under moderate operating conditions that ensure system reliability and durability with no requirement for additional complex condensers [178,179], which are needed in vacuum membrane distillation (VMD) and sweeping gas membrane distillation (SGMD) [180].…”

“…Population increase and rapid industrial development imposed additional demand on freshwater resources [1,2]. Although developed countries enjoy good quality water provided by centralized municipal water supply systems, safe drinking water remains scarce in developing countries.…”

Outlier and Normality Testing of the Residuals from the Carreau-Yasuda Model in Fitting the Rheological Behavior of the Non-Newtonian fluid TF2N

“…D'Agostino developed a variety of normality tests, the most extensively used of which is the omnibus K2 test [25]. More and more nonlinear regression curve fitting exercise works are reporting extensive testing for the normality of the residuals [60][61][62][63][64][65][66][67][68].…”