Papers by Keyword: Filtration

Abstract: In this work, the effect of peat clay particles (PCP) was investigated as pore former of polysulfone (PSf) hollow fiber membrane properties. Preparation of polysulfone membrane dope solution conducted by phase inversion technique using wet spinning method. A homogeneous dope solution is added with peat clay from four composition variations of 0-6 wt%. Followed by mixed dope until homogeneous for an hour at room temperature (~29 °C). The preparation of peat clay before used is by having it calcinated at 600 °C for 1 hour, then sifted to a size of 120 mesh. The hollow fiber membrane is casted using the wet spinning method with the dope solution flow rate set at 4 mL/min and the bore fluid flow rate at 4 mL/min. The hollow fiber membrane that has been formed is analyzed by FTIR, contact angle, water absorption, and porosity. The characteristics of the membrane show that the functional group in the addition of peat clay in the absorption of Si-OH and Si-O-Si. The specific spectrum of PSf-PEG/PC is indicated by peak wavenumbers 872 – 874 cm^-1. Polysulfone hollow fiber membrane mixed with peat clay shows the contact angle on the membrane surface shows hydrophobic characteristics without addiction of peat clay particles and become slightly hydrophilic with peat clay addiction of 71.28°. In addition, water absorption in each sample increases with the addition of peat clay from 0 to 4 wt%. The ability of water absorption increased to 32.51%, and membrane porosity increased from 23.66% to 38.87%. It is concluded that polysulfone hollow fiber membranes are enhanced by adding peat clay as a pore builder and hydrophilic additives and become less fouling in future application for water/wastewater treatment.Keywords: Peat clay, hollow fiber membrane, polysulfone, wet spinning, montmorillonite

Abstract: Water pollution poses a significant challenge to water consumption, particularly in relation to drinking purposes. Various factors such as industrial discharge, improper waste management, waste build-up, and natural activities contribute to the contamination of water bodies. Adequate water treatment plays a crucial role in the preservation of water quality and compliance with environmental regulations. The treatment process typically involves the application of physical, chemical, and biological techniques, with a common reliance on chemical substances and intricate systems. Recent studies have increasingly explored the utilization of cost-efficient natural materials for water treatment, highlighting benefits like affordability, user-friendliness, health advantages, and widespread availability. This particular investigation aimed to assess the suitability of selected natural substances for the treatment of wastewater, focusing primarily on methods like adsorption, absorption, and filtration. A number of earth materials, notably three distinct types of clays prevalent in Sri Lanka, were singled out for examination. The findings unveiled that these clays predominantly consist of over 75% iron in their mineral composition, with certain samples displaying finer particles to enhance porosity and permeability. These raw materials exhibit potential for the fabrication of wastewater treatment systems intended for the elimination of suspended particles, dissolved solids, heavy metals, pathogens, oils, and toxic compounds. Their distinct chemical properties render them appropriate for catalytic reactions and advanced chemical processes

Abstract: South Kalimantan-Indonesia is known to have extensive peatlands reaching 15% of a total peatland in Kalimantan. Due to that peat land water is mostly found and claim as abundant water sources. However, based on quality, peat land water has poor characteristic with high natural organic matter content. Therefore, peat water treatment is necessary to treat using effective method such as hybrid conventional filter and membrane using hollow fibre PVDF-TiO₂/SBE. This study aims to investigate the variation of media filter thickness and filtration pressure of hollow fibre (HF) PVDF-TiO₂/SBE membrane peat water treatment by filtration pre-treatment and HF membrane ultrafiltration. HF PVDF-TiO₂/SBE membrane was prepared by wet spinning method using spinneret set up. Hybrid process was divided into two steps: 1) conventional filter as pre-treatment and 2) HF ultrafiltration membrane under cross flow system. The filter media was used in this work is silica sand and activated carbon with varied thickness 30:10 and 10:30 cm. The HF membrane structure was analysed via scanning electron microscopy (SEM) to investigate the membrane morphology. The results show the fabricated HF membrane has a finger like-sponge sandwich structure morphology. In addition, 30:10 cm (silica sand: activated carbon) thickness exhibits TDS and turbidity removal of 92.18 and 61.37%, respectively as conventional filter pre-treatment. In other hand, HF membrane successfully removed TDS and turbidity of peat water up to 98.68% and 92.41% at 2 bar of filtration pressure. The highest permeate flux of HF membrane conducted of 13.055 Kg.m^-2.h^-1 at 3 bar. Conclusion of this work is the peat water treatment using activated carbon: silica filtration pre-treatment and HF membrane ultrafiltration can provide clean water with maximum turbidity and TDS removal.

Abstract: There are the results of studies on increasing the sedimentation stability of cement-mineral suspensions intended to fill hollow spaces in fractured rocky soils and strengthen dispersed soils, as well as to prevent filtration processes in soils.To ensure the sedimentation stability of cement-mineral suspensions, it is proposed to use the water solutions of hydroxyl-containing polymers prone to swelling as a dispersion medium (mixing water): water solutions of polyvinyl alcohol (PVA) in 4% - 8% concentration. The concentration range of polymer solution from 4% to 8% was established in order to prevent coagulation during storage and to ensure the production of polymer films from water PVA solutions.The research results showed that polyvinyl alcohol provides the high kinetic sedimentation stability of cement-mineral systems determined by hydrodynamic factors as follows: the viscosity and density of the water polymer solution. The higher the viscosity and density of the water solution of polyvinyl alcohol (concentration), the higher the sedimentation stability of cement-mineral suspensions.

Abstract: Controlling the filtration characteristics of any drilling fluid does not only include the control of the filtrate volume penetrating into the formation; but also the ability of the mud to deposit a thin low-permeability filter cake on the wall of the wellbore quickly. The permeability of the filter cake is very dependent on the particle size because when small size particles are used, the permeability decreases, because of the fact that colloidal particles get packed very tightly. This study investigated the filtration and filter cake characteristics of water-based mud (WBM) using fibrous cellulose from Tiger Nut waste and the guar gum. American Petroleum Institute (API) Recommended Practice Standard Procedure for Field Testing Drilling Fluids, API RP 13B-1 was applied during the analysis. Statistical analysis of the experimental data was conducted and the R² value (0.99) showed that the experimental method adopted was replicable. Mud samples B2 and C2 gave an optimum result and their mud cakes developed under High-Temperature High-Pressure (HTHP) condition were dried and further analyzed with scanning electron microscope (SEM). The results showed that the filter cakes SEM structure for cellulosic fibrous from agro waste and guar gum exhibits similar characteristics; and the mud cakes was firm after soaking with 15% HCl for thirty minutes but started dissolving after one hour. The SEM analysis inferred that the filter cake morphology shows a good particle-pore interlocking for sample C2 than B2.

Abstract: The article examines the operational reliability and technical efficiency assessment of polymer (geomembranes) and geocomposite (bentonite mats) impervious channel coating developed designs. Criteria for impervious channel screen reliability and technical efficiency are proposed based on the domestic and foreign experience generalization in the composite materials use and conducted efficiency studies in terms of water permeability, strength, efficiency, and durability. Two options of developed highly efficient structures for polymer and geocomposite channel linings are presented. The graph of change in screen failure-free operation probability was obtained based on the impervious screen failure-free operation probability calculation results, depending on the survey areas and the failure amount.

Abstract: Metallic contamination is a major challenge in multiple semiconductor processes, including photolithography and wet etch and cleans (WEC). Though there are several contributors to metallic contamination, significant efforts have focused on improving the incoming quality of process chemicals, especially commodity chemicals. Another key contributor to on-wafer metallic contamination is water (H2O), which is used to dilute most aqueous chemicals. Single Particle Inductively Coupled Plasma Mass Spectroscopy (SP-ICP-MS), a technique relying on time-based resolution of pulses generated during a standard ICP-MS analysis, is used to aid the understanding of metal particle contamination in water and process chemicals.In this paper, we studied water and 30% Hydrogen Peroxide (H2O2), two of the most widely used chemicals across all WEC processes. We used a high purity grade of 30% H2O2, further diluted to a typical use concentration (5% by volume) using two grades of Deionized Water (unfiltered and filtered) where the concentration of metallic particles was the key variable. The metals studied included Iron (Fe), Chromium (Cr), Zinc (Zn), Titanium (Ti), Nickel (Ni) and Aluminum (Al), representing some of the most commonly observed metallic contaminants in H2O2 and water. After analyzing the distribution of contaminants in the chemicals, filters were introduced into the system to observe the impact of filtration on metal removal. The importance of filtration on the overall quality of the diluted process chemical was demonstrated by using a Polysulfone (PS) membrane to filter the lower grade Deionized Water (DIW).

Abstract: Polysulfone/ Recam® composite membranes were prepared via the wet-phase inversion method. The interactions between polysulfone and additive were revealed by Fourier-transformed infrared spectroscopy and atomic force microscopy. Material properties, such as thermal and mechanical ones, were also analyzed. The increase of rugosity by augmenting the Recam® content was depicted by AFM images. Infrared spectroscopy provided very useful information about the interactions between polymer chains and additive. Thermal stability and mechanical resistance showed dependence on the additive content, which were higher for higher contents.

Abstract: The paper presents the results of the development of the technology of centrifugal-die forming of biologically active fibrous materials. The modification of biologically active polypropylene fibers was carried out directly at the process of their production in the field of centrifugal forces of rotating reactor during their molding from polypropylene melt. The properties of the obtained ion-exchange and biologically active polymer fibers are studied. It is shown that obtained and modified by the centrifugal-die method polypropylene fibers can be used as biologically active fibers.

Abstract: Innovation in water filtration media leads to tremendous focus in academia due to fresh water source declining and contamination. Electrospinning is considered as new and effective protocols in synthesizing filtration membrane for this purpose. Electrospun membrane of PVDF and CA composite at different ratios has been fabricated for water filtration application. The membranes were characterized using TGA, FTIR, viscometer, conductivity testing, contact angle and FESEM. TGA result showed a shifting in thermal stability with respect to the increasing PVDF ratio (90P10C). FTIR analysis showing five membrane samples had the same functional groups included C-F, =C-H, C-O, C=O, C-H and O-H groups. The FESEM showed a nanofiber with an average diameter of 0.43324 nm and posses the average pore size of 0.3068 μm. Contact angle of the membrane is increased by the PVDF increment (130^o @ 10:90 ratio). The filtration analysis of lake water demonstrates the best performing membrane 90P10C give 84.9% rejection at a high flux (26,253 L m^-2 h^-1), low turbidity (0.38 NTU) and comply to Malaysia Water Standard Type 1