Stand-alone water treatment: performance of electrospun nanofibers

The aim of this study was to evaluate the use of nanofiber microfiltration membranes, spun by an innovative electrospinning technique, in water filtration applications. This study bridges between developments in electrospinning techniques for the production of flat sheet membranes and the application of these membranes in water filtration. The functionalized or non-functionalized for the removal of pathogens was investigated, in term of chemical oxygen demand, total suspend solid and ammonium in the waste water. Physical properties such as clean water permeability (CWP) and strength were also examined. The results showed a very good removal of TSS (range 94.83-97.34%), COD (89.32-95.27%) and NH3-N (64.48-72.87%). These test showed that the electrospun membranes can be used for water filtration applications

Morphological and separation performance study of polysulfone/titanium dioxide (PSF/TiO2) ultrafiltration membranes for humic acid removal

In this study, polysulfone (PSF) hollow fiber membranes with enhanced performance for humic acid removal were prepared from a dope solution containing PSF/DMAc/PVP/TiO2. The main reason for adding titanium oxide during dope solution preparation was to enhance the antifouling properties of membranes prepared. In the spinning process, air gap distance was varied in order to produce different properties of the hollow fiber membranes. Characterizations were conducted to determine membrane properties such as pure water flux, molecular weight cut off (MWCO), humic acid (HA) rejection and resistance to fouling tendency. The results indicated that the pure water flux and MWCO of membranes increased with an increase in air gap distance while HA retention decreased significantly with increasing air gap. Due to this, it is found that the PSF/TiO2 membrane spun at zero air gap was the best amongst the membranes produced and demonstrated > 90% HA rejection. Analytical results from FESEM and AFM also provided supporting evidence to the experimental results obtained. Based on the anti-fouling performance investigation, it was found that membranes with the addition of TiO2 were excellent in mitigating fouling particularly in reducing the fouling resistances due to concentration polarization, cake layer formation and absorption

Submerged ultrafiltration for minimizing energy process of refinery wastewater treatment

Refinery wastewater treatment is needed especially in the oil-producing arid regions such as oil refineries due to water scarcity. One of potentially applicable process to treat refinery wastewater is a submerged membrane technology. However, the application of submerged membrane systems for industrial wastewater treatment is still in its infancy due to significant variety in wastewater composition and high operational costs. Aim of this study was to investigate ultrafiltration (UF) membrane morphology and performance for refinery produced wastewater treatment. Submerged UF bundle was equipped using polyvinylidene fluoride (PVDF) hollow fibers, which added by dispersing lithium chloride monohydrate (LiCl.H2O) and titanium dioxide (TiO2). The comparison of morphological and performance tests was conducted on prepared PVDF ultrafiltration membranes. Distinctive changes were observed in membrane characteristics in term of membrane wettability, tensile testing and roughness measurement. Mean pore size and surface porosity were calculated based on permeate flux. Fouling characteristics for hydrophilic PVDF hollow fibers fouled with suspended solid matter was also investigated. Mixed liquor suspended solid (MLSS) of 3 g/L and 4.5 g/L were assessed by using submerged PVDF membrane with varied air bubble flow rates. Results showed that effect of air bubbles flow rate of 2.4 ml/min increased flux, total suspended solids (TSS) and sulfide removal of 148.82 L/m2h, 99.82 % and 89.2%, respectively due to increase of turbulence around fibers, which exerts shear stress to minimize particles deposited on membrane surface. It was concluded that submerged ultrafiltration is an available option to minimize energy process for treating such wastewater solution

A-state-of-art Review on Additives Function on Polymeric Membrane Performance for Wastewater Treatment

In this article, the recent development of polymeric membrane fabrication using additive for wastewater treatment is presented. The application of this substance has been recognized reliable to increase membrane performance against fouling phenomenon, especially for purifying industrial wastewaters that mostly have high loading of hazardous pollutants. The effects of modification techniques through additives addition on membrane casting solution are considerably included. This paper also discusses membrane fouling mechanism and other existing technologies available for treating contaminated water. Despite the existence of review paper discussing membrane fouling mitigation on literature, there is still the need of comprehensive review related to the novel technology regarding additive blending on membrane, especially on polymer-based membrane for water pollution control. Eventually, clear conclusion can be drawn that the suitability of additive substances and its composition as well as suitable operating conditions have great leverage on polymeric membrane performance regarding its anti-fouling and hydrophilic level

Mathematical model of optimum composition on membrane fabrication parameters for treating batik Palembang wastewater

Batik Palembang wastewater is characterized by high levels Natural Organic Matter (NOM) concentration. In order to reuse the wastewater, removal of NOM and contaminants is necessary. To improve the performance of NOM removal processes we need to optimize the flux of membrane produced. Majority of the wastewater treatment processes are multi-variable and optimization through the classical method is inflexible, unreliable and time-consuming. In this study, we employ Response Surface Methodology (RSM) to optimize and analyze the effect of independent factors, namely polymer concentration (x1), additive 1 concentration (x2) and dope temperature (x3) on a treatment process to obtain the maximum removal NOM. RSM 2 3 had already emerged as a tool of optimization analysis on the industry scale. Various statistical and mathematical assumptions inherent in this method and is an advantage and shortcomings in its practical application excellence. In order to fulfil the environment standardization of wastewater based on Minister Regulation No. 5/2014, the membrane was produced in optimum composition to achieve the maximum output. We use a full factorial design and Central Composite Design (CCD) of RSM to determine the significant variables and optimum condition for hybrid process of coagulation-UF membrane with respect to NOM removal and flux. Statistical analysis of full factorial design showed that the main effect of three independent factors contributed significantly. Optimum condition was achieved and showed the maximum flux of 198.82 L m3/h and NOM removal of 90.32%