Improved Nylon 6,6 Nanofiber Membrane in A Tilted Panel Filtration System for Fouling Control in Microalgae Harvesting

Abstract

The competitiveness of algae as biofuel feedstock leads to the growth of membrane filtration as one of promising technologies for algae harvesting. Nanofiber membrane (NFM) was found to be efficient for microalgae harvesting via membrane filtration, but it is highly limited by its weak mechanical strength. The main objective of this study is to enhance the applicability of nylon 6,6 NFM for microalgae filtration by optimizing the operational parameters and applying solvent vapor treatment to improve its mechanical strength. The relaxation period and filtration cycle could be optimized to improve the hydraulic performance. For a cycle of 5 min., relaxation period of ≤2 min shows the highest steady-state permeability of 365 ± 14.14 L m−2 h−1 bar−1, while for 10 min cycle, 3 min. of relaxation period was found optimum that yields permeability of 402 ± 34.47 L m−2 h−1 bar−1. The treated nylon 6,6 NFM was also used to study the effect of aeration rate. It is confirmed that the aeration rate enhances the steady-state performance for both intermittent and continuous mode of aeration. Remarkably, intermittent aeration shows 7% better permeability than the full aeration for all tested condition, which is beneficial for reducing the total energy consumption.

Filterability of Polysulfone Membrane in a Tilted Panel System for Activated Sludge Filtration

“…The effect of the aeration rate was evaluated by comparing the steady state permeability at different air flow rates ( Figure 5). Overall, both PSF-1 and PSF-3 showed a steady increase in permeability with an increment in aeration rate, which is consistent with other findings [16,35,36]. An aeration rate of 1.8 L•min −1 improves water permeability by ±10% compared to the non-aerated system.…”

Membrane Fouling in Algal Separation Processes: A Review of Influencing Factors and Mechanisms

“…On the other side, it is worth mentioning the eventual positive impact of the cake layer: A compact and more resistant cake layer acts as a secondary filtration layer, protecting the membrane surface from small organics molecules responsible for irreversible fouling (Low et al, 2016;Fortunato et al, 2020;Novoa et al, 2020). Javadi et al (2014) found out that an increase in the cake layer resistance, induced by a compact and nonporous structure, improved the permeate quality (Javadi et al, Fletcher et al, 2011a;Wang et al, 2014;Fortunato et al, 2017;Bagheri and Mirbagheri, 2018;Mat Nawi et al, 2020 Irreversible: removed by chemical cleaning…”

“…The membrane proprieties and configuration influence their surface properties and define the dominating fouling mechanism and overall fouling severity (Figure 3). The membrane materials directly impact properties, such as morphology (roughness, pore size, and distribution), hydrophilicity/hydrophobicity and electric charge (Liao et al, 2018;Zhang and Fu, 2018;Mat Nawi et al, 2020). On the other hand, membrane configuration also FIGURE 3 | Summary of fouling contributing factors in algal membrane separation processes.…”

“…An appropriate membrane pore size is required for an optimal operation, as it determines the retention of algal biomass during harvesting and the dominating fouling mechanism (Liao et al, 2018;Zhang and Fu, 2018;Mat Nawi et al, 2020). The molecular weight distribution of foulants relative to the membrane pore size regulates the fouling propensity, and, thus, the impact of membrane pore size on the fouling development has been widely investigated (Fletcher et al, 2011b;Bilad et al, 2014;Wang et al, 2014;Marbelia et al, 2016;Elcik and Cakmakci, 2017;Krzeminski et al, 2017;Liao et al, 2018;Zhang and Fu, 2018;Zhang Y. et al, 2019).…”

One-Pot Polymerization of Dopamine as an Additive to Enhance Permeability and Antifouling Properties of Polyethersulfone Membrane

“…To deal with this problem, pursuit on the effective methods to reduce and control membrane fouling have been done through various endeavors [ 8 , 11 , 12 , 13 ]. Though the mechanism and behavior of fouling are complex, it has been widely reported that increasing the hydrophilicity of the membrane can be one of the viable solutions to limit the rate of foulant adsorption and thereby reducing the membrane fouling severity [ 14 , 15 , 16 , 17 , 18 , 19 ]. The enhancement of the hydrophilicity can be done by introducing a hydrophilic additive into the membrane materials through various techniques, such as blending [ 20 , 21 , 22 , 23 , 24 ], coating [ 25 , 26 ], grafting [ 27 ] and so forth.…”