Filter System Research Articles

Assessment of an Advanced Water Filtration System for Enhanced Water Purification

The study confirms the effectiveness of a state-of-the-art water filtration system in purifying urban tap water, river water, and groundwater. The system, which uses activated carbon, ceramic, and reverse osmosis (RO) filtration, significantly improved water quality by removing physical, chemical, and biological contaminants. Key results include: The system achieves a turbidity reduction of up to 99.5%, adhering to WHO standards. The system removes over 96% of volatile organic compounds (VOCs) and chlorine, and more than 99% of heavy metals like lead and arsenic. The water is completely free of harmful bacteria, guaranteeing its microbiologic safety. There has been a 98.2% reduction in total dissolved solids (TDS) in groundwater. The study highlights the system's adaptability to diverse environments, including urban, rural, and industrial settings. Future research could focus on improving the system's energy efficiency and sustainability.

Design, Development and Analysis of Future Tree and Air Filtration System

Design, Development and Analysis of Future Tree and Air Filtration System

Enhancing Energy Efficiency: Cutting-Edge Oil Filtration and Treatment Systems in Electric Transformers

Enhancing Energy Efficiency: Cutting-Edge Oil Filtration and Treatment Systems in Electric Transformers

Assessing the efficacy of surgical mask-based modified conventional filtration chambers in eradicating harmful microorganisms from wastewater

ABSTRACT Subsequent to the COVID-19 pandemic, waste management posed escalating challenges attributed to the imprudent disposal of medical waste, notably surgical masks. Hence, the present investigation was undertaken concomitantly to confront the dual concerns of mitigating environmental pollution and managing discarded face masks. The experimental methodology entailed the utilization of filtration chambers featuring surgical mask layers of distinct thicknesses, labeled as Treatment-0 (no mask layer), Treatment-1 (5 mm mask layer), Treatment-2 (10 mm mask layer), and Treatment-3 (15 mm mask layer), to eliminate pathogenic microorganisms from contaminated river water, Buriganga. At the end of the observation, Treatment-3 exhibited the most significant declination (88.15%) of the bacterial population. This treatment also removed most pathogens, including E. Coli (19.85%), total coliform (16.42%), and fecal coliform (12.02%). The findings underscore the significance of modern filtration systems and the efficient, ecologically viable recycling of medical waste, with a specific focus on surgical masks.

Cold sintering of α- and γ-modifications of aluminum oxohydroxides: A low-temperature route to porous corundum ceramics

Objectives. To obtain porous corundum ceramics using an innovative cold sintering process starting from different phase modifications of aluminum oxohydroxide — boehmite γ-AlOOH and diaspore α-AlOOH; to study the phase and structural properties of the resulting materials; and to assess their permeability to water.Results. Cold sintering enables the formation of single-phase corundum ceramics with an open porosity of 47.9% directly from the initial boehmite powder with the addition of 5 wt % corundum in the presence of 20 wt % water at a temperature of 450°C, mechanical pressure of 220 MPa, and isothermal exposure for 30 min. Under the same conditions of cold sintering, a mixture of diaspore and boehmite was transformed into α-AlOOH ceramics. This then turned into corundum with an open porosity of 39% when calcined in air at 600°C for 1 h. The resulting materials had permeability for pure water above 5000 L/(m2∙h∙bar).Conclusions. Cold sintering is a promising approach to producing porous corundum ceramics which can be used in filtration systems. Compared to traditional ceramic technology, the new approach reduces energy, time, and labor costs in the material manufacturing. It also eliminates the need to use auxiliary substances (binders, pore-forming agents, etc.).

Interference cancellation system of a microwave resonator filter for 4G and 5G applications

This paper aimed at designing a microwave resonator filter for use in 4G and 5G applications. A band resonator filter was designed and implemented using microstrip technology. Poor performance of a microstrip microwave resonator filter is due to spurious harmonics and unwanted frequencies which are always present and cause interferences of signals hindering effective communication. The coupling matrix was first obtained using polynomial functions of transmission and reflection coefficients. A cost function for optimization was developed and particle swarm optimization techniques were used to optimize the coupling matrix. The transversal matrix was developed and converted to the folded matrix for practical filter implementation. A bandpass filter was designed and simulated using high- frequency structure simulator software. Unwanted frequencies are eliminated by employing a novel square open loop resonator structure. The filter was designed to specification and the results show that unwanted frequencies were eliminated corresponding to the frequency of the outer resonator and therefore performs better than comparable filter.

A novel electrochemical membrane filtration system operated with periodical polarity reversal for efficient resource recovery from nickel nitrate laden industrial wastewater

The economical and efficient removal of nickel nitrate from industrial wastewater remains a challenge. Herein, we developed an innovative electrochemical membrane filtration system that used a periodic polarity reversal process to adjust the acid-base environment near membrane interface for the recovery of nickel (II) and ammonia. The Ru based electrocatalytic layer could boost the selective reduction of nitrate to ammonia by generating atomic hydrogen, resulting in the precipitation of Ni2+ by the increasing pH at the membrane interface. Then, the precipitation of Ni(OH)2 could be effectively stripped and collected under the periodic polarity reversal process. In-situ interfacial measurements demonstrated that the polarity reversal process enabled a reversible transformation between strongly acidic (pH < 2) and alkaline (pH > 13) environments within a 200 µm range at the membrane interface. In continuous flow operation treating real industrial wastewater containing 96.7 mg-N L−1 nitrate and 135.0 mg L−1 Ni2+, the system demonstrated the capability to achieve 92.5 ± 2.6 % nitrate removal (with a recovery efficiency of 15.1 ± 1.9 g-NH3 kWh−1) and 99.7 ± 0.1 % Ni²⁺ removal (with a recovery efficiency of 24.9 ± 2.4 g-Ni kWh−1). Additionally, the specific treatment cost was approximately $0.17 m−3, attributed to the recovery of Ni(OH)₂ and ammonia. Furthermore, this system could deliver a significant economic benefit ($1.64 per m3) for treating a high concentration real wastewater (331.5 mg-N L−1 nitrate and 1496.3 mg L−1 Ni2+), outperforming traditional alkali precipitation and biological nitrification/denitrification processes. Overall, our study presents an economical and sustainable method for recovering valuable chemicals from wastewater containing heavy metals and inorganic nitrogen, potentially advancing cost-effective water treatment technologies.

Replicating biological 3D root and hyphal networks in transparent glass chips

Replicating the complex 3D microvascular architectures found in biological systems is a critical challenge in tissue engineering and other fields requiring efficient mass transport. Conventional microfabrication techniques often face limitations in creating extensive hierarchical networks, especially within bulk materials. Here, we report a versatile bioinspired approach to generate optimized 3D microvascular networks within transparent glass matrix by transcribing the natural growth patterns of plants and fungi. Plant seeds or fungal spores are first cultivated on nanoparticle-based culture media. Subsequent heat treatment removes the biological species while sintering the surrounding compound into a solidified chip with replica root/hyphal architectures as open microchannels. A diverse range of architectures, including the hierarchical branching of plant roots and the intricate networks formed by fungal hyphae, can be faithfully replicated. The resultant glass microvascular networks exhibit high chemical and thermal stability, enabling applications under harsh conditions. Fluid flow experiments validate the functionalities of the fabricated channels. By co-cultivating plants and fungi, hierarchical multi-scale architectures mimicking natural vascular systems are achieved. This bioinspired manufacturing technique leverages autonomous biological growth for architectural optimization, offering a complementary approach to existing microfabrication methods. The transparent nature of the glass chips allows for direct optical inspection, potentially facilitating integration with imaging components. This versatile platform holds promise for various engineering applications, such as microreactors, heat exchangers, and advanced filtration systems.

MXene laminar membrane functionalized with Pd-Cu for efficient and selective nitrate reduction to ammonia

Conversion of nitrates (NO3−) to ammonia (NH3) by electrocatalysis is a sustainable approach for resource utilization from wastewater. Nonetheless, this conversion is often constrained by sluggish mass transfer. In this study, we developed a laminar membrane using Pd-Cu bimetal functionalized 2D MXene (Ti3C2Tx) to accelerate the mass transfer during NO3− reduction. The resulting membrane exhibited outstanding NO3−-N removal efficiency (99.0 ± 0.5 %) and NH4+-N selectivity (74.1 ± 0.6 %), and maintained excellent NO3−-N removal efficiency with various influent NO3− concentrations. Its nitrate reduction performance was relatively stable even in low-conductivity influents similar to surface water, presence of dissolved oxygen (DO) or after membrane fouling. The NO3−-N removal rate in the electrocatalytic filtration system was 11 times that without filtration, attributed to a ten-fold improvement in the mass transfer constant (km) with filtration and the increased active sites for NO3− reduction by 2D MXene. The filtration process ensured a higher NH4+-N selectivity by preventing the re-oxidation of NH4+-N on anode. The mechanism of nitrate reduction on the laminar membrane was predominantly direct reduction, and the spatial distribution analysis of atomic hydrogen (H*) demonstrated that it was difficult for H* to participate in nitrate reduction reaction due to the strong adsorption of H* on the membrane. Theoretical calculations suggested that Pd-Cu bimetal could greatly diminish the energy barriers for NO3− to NH4+ and enhance the conversion efficiency. This finding offers valuable insights for developing efficient and robust nano-laminar membranes aimed at nitrate removal and ammonium production in water.

Advancements in Inorganic Membrane Filtration Coupled with Advanced Oxidation Processes for Wastewater Treatment.

Membrane filtration is an effective water recycling and purification technology to remove various pollutants in water. Inorganic membrane filtration (IMF) technology has received widespread attention because of its unique high temperature and corrosion resistance. Commonly used inorganic membranes include ceramic membranes and carbon-based membranes. As novel catalytic inorganic membrane processes, IMF coupled with advanced oxidation processes (AOPs), can realize the separation and in situ degradation of pollutants, thus mitigating membrane contamination. In this paper, the types and performance of IMF are discussed. The influencing factors of inorganic membranes in practical wastewater treatment are summarized. The applications, advantages, and disadvantages of the coupled process of IMF and AOPs are summarized and outlined. Finally, the challenges and prospects of IMF and IMF coupled with AOPs are presented, respectively. This contributes to the design and development of coupled systems of membrane filtration with inorganic materials and IMF coupled with AOPs for practical wastewater treatment.

Influence of coconut and castor oil coating on engine intake non-woven filter performance

PurposeThis research focuses on the development and characterization of oil-wetted spun-bonded polypropylene (PP) non-woven filters for improved air intake systems in automobiles. The study aims to enhance engine performance, durability, fuel economy and emission reduction by addressing key aspects such as contaminants filtration efficiency, loading capacity, pressure drop, temperature performance and longevity.Design/methodology/approachThe research methodology involves the utilization of textile fabrics, particularly oil-wetted spun-bonded PP non-woven filters, renowned for their effective particle collection capability from intake air. Experiments were conducted using a Box–Behnken design with three variables – oil concentration, areal density and dust quantity – each at three different levels to establish correlations with the filter’s dust holding capacity (DHC) and pressure drop.FindingsThe findings indicate that immersing particles in oil-coated medium significantly enhances the filter’s DHC. Notably, castor oil as a coating demonstrates remarkable results, with a 97.53% increase in DHC and a high particulate matter filtration efficiency of 94.12%.Originality/valueThis study contributes to the originality of research by emphasizing the importance of oil density in determining the filter’s DHC and filtration efficiency. Furthermore, it highlights the superiority of castor oil over coconut oil-coated filter media, advancing air intake and/or filter systems for automotive engines.

Characterization of hybrid silicate materials based on ceramic glazes and waste London underground dust

In “London Underground” stations, a high concentration of dust particles containing organic and inorganic matter of varying chemical composition. “London underground dust” is created from train wheels and brakes grinding against steel tracks and collected in filtration systems. The experiment will focus on using “London Underground Dust” to colour the ceramic facing tiles intended for re-use in newly built London Underground stations. The phase composition, particle size distribution surface area, morphology, and thermal behavior of collected dust were studied by XRD, XRF, SEM-EDS, BET, heating microscopy, STA-MS, UV–VIS spectroscopy. The substrate tiles for glazing experiments were prepared from local London clay. The mixtures of glazes and collected or milled dust were sprayed on the substrate tile's surface, dried and finally fired at 1060 °C. The influence of used materials weight ratio and dust milling time were shown as crucial parameters to obtain optimal final glaze colour.

Development of a local wall concentration model for the design of single pass tangential flow filtration (SPTFF) systems with viral vector surrogates

Recent advances in the use of viral vectors for gene therapy has created a need for efficient downstream processing of these novel therapeutics. Single-pass tangential flow filtration (SPTFF) can potentially improve final product quality via reductions in shear, and it can increase manufacturing productivity via simple implementation into continuous/intensified processes. This study investigated the impact of variations in pressure and flow rate along the length of the membrane on overall SPTFF performance. Constant-flux filtration experiments at feed fluxes from 14 to 420 L/m2/h (Reynolds numbers <20) were performed using Pellicon® 3 TFF cassettes with fluorescent nanoparticles as model viral vectors. The location of nanoparticle accumulation shifted towards the filter outlet at high conversion and was also a function of the permeate flow configuration. These phenomena were explained using a newly developed concentration polarization model that predicts the distribution in local wall concentration over the length of the membrane. The model accurately captured the observed nanoparticle accumulation trends, including the effects of the permeate flow profile (co-current, divergent, or convergent flow) on nanoparticle accumulation within the SPTFF module. Nanoparticle accumulation at moderate conversion was more uniform using convergent flow, but nanoparticle accumulation at 80 % conversion (5x concentration factor) can be minimized using a divergent flow configuration. The local wall concentration model was also used to evaluate the critical flux by assuming that fouling occurs when the nanoparticle concentration at any point along the membrane surface exceeds 15 % by volume. These results provide important insights for the design and operation of SPTFF technology for inline concentration of viral vectors.

Performance evaluation of integrated Upflow Anaerobic Sludge Blanket reactor with trickling filter used for municipal wastewater treatment and effluent reuse potential for agriculture

Effluent reuse is a rapidly growing field of research where assessing the quality of effluent is one of the focus areas. This research examines the viability of using wastewater in agriculture by testing an integrated Upflow Anaerobic Sludge Blanket (UASB) reactor with a trickling filter (TF) system during the dry season. Compliance monitoring was conducted for 30 days from May 11 to June 9 of 2021. Samples were collected, handled, and analyzed following standard wastewater analysis procedures for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), volatile suspended solids (VSS), cations, anions, heavy metals, E. coli, and helminth egg. The UASB-TF system in Kality wastewater treatment performed well in removing COD, BOD5, and TSS with average removal rates of 80.5%, 82.9%, and 80.9%, respectively, compared well with similar treatment configurations. The effluent quality satisfied the national inland discharge limit with a residual concentration of 125.1 mg/L for COD, 61.7 mg/L for BOD5 and 85.8 mg/L for TSS. On the other hand, high concentrations of chromium, nitrate-nitrogen, and helminth egg count restricted effluent reuse for agricultural purposes due to high health risks and environmental contamination. We found out that discharging industrial sewage into the domestic sewer network could inhibit microbial growth and affect the biological treatment processes. Furthermore, adopting integrated treatment systems in developing countries might face operational challenges and monitoring nitrate, helminth egg, and heavy metals would help provide timely operational feedback. An appropriate tertiary treatment unit—constructed wetlands or polishing ponds—is therefore needed to be introduced to ensure effluent reuse for agricultural purposes.

Monitoring and control of air filtration systems: Digital twin based on 1D computational fluid dynamics simulation and experimental data

This study presents the development of a digital model based on one-dimensional computational fluid dynamics for the monitoring and control of filtering systems used for removing flour, dust, and other particulates from the airflow arriving from various sections of industrial production plants.Focusing on a pilot plant equipped with a cyclone bag filter, historical experimental data was integrated with the results of a one-dimensional fluid dynamics simulation model to create a digital twin capable of real-time control and regulation of industrial plants. In particular, measured pressure drop data under different clogging conditions were interpolated to generate the characteristic curves of the filter under various clogging conditions, to be implemented within the digital model of the plant. The generated model, validated through a dedicated experimental campaign, accurately predicted the airflow rate and pressure distribution across the plant. The system’s capability to adapt to changing operational conditions, such as clogging, was demonstrated through simulation, highlighting the model’s utility in maintaining the desired operation levels while minimizing the need for extensive sensor networks.The analyzed case study in the field of air filtration systems aims to fill the gap in the scientific literature related to the application of Digital Twin technology to the control of industrial manufacturing plants. The findings highlight the potential of digital twins in monitoring and control, as well as predictive maintenance, of industrial systems. The findings highlight the potential of Digital Twins in monitoring and control, as well as predictive maintenance, of industrial systems. Future research activities will explore the model’s applicability in failure and anomaly detection, to further enhance predictive maintenance of air filtering systems.

Study the Effectiveness of Household Water Filtration Systems in Eliminating Plastic Particles in Mosul City, Iraq

Study the Effectiveness of Household Water Filtration Systems in Eliminating Plastic Particles in Mosul City, Iraq

NanoRidge filters: Fabrication strategies and performance optimization for nano-scale microfluidic particle filtration.

Filters with high throughput, minimal dead volume, and greater sensitivity to particle size are needed, which traditional benchtop filtration cannot provide. Leveraging microfabrication techniques developed by the electronics and optics industries, the filters presented here feature a unique serpentine "NanoRidge" structure, offering a continuous filtration gap spanning over three meters on a compact 4 × 14.5 mm2 footprint. This design provides more precise size filtration cut-offs and consistent flow paths compared to traditional membrane filtration systems. Despite challenges associated with glass substrate deformation impacting uniform filter gap sizes, the study provides valuable insights into the development of NanoRidge filters (NRFs) for enhancing filtration efficiency in preparatory techniques and sample analysis. This study describes the fabrication and testing of these new filter types and directly compares the performance to traditional membrane filters using the metrics of particle size cut-off (the smallest difference in particle size which can be filtered vs passed) and particle loss. The NanoRidge filters were characterized using imaging (during fabrication, post-fabrication and use, fluorescent particles captured and small molecule dye), pressure and flow measurements, and a series of particle sizes "filter or pass" studies. Particle capacity (100-250 nm) ranged from 5 × 108 to 7 × 109 in 1 ml samples at a flow rate of 100 μl/min with backpressure in the range of 1-3 Bar. The optimized fabrication procedure for the 150 nm NRF yielded a small particle recovery of 95% while also achieving a large particle filtration of 73%. High filtration efficiency was also proven in the final 60 and 80 nm NRF fabrication procedures at 96% and 91%, respectively.

Performance evaluation and factors influencing a drinking water treatment plant, Shire Indassilassie, Ethiopia

This research assesses the efficacy of the water treatment plant in Shire Indassilassie, Tigray, Ethiopia, focusing on the slow sand filtration system. Despite the inclusion of horizontal roughing filtration and a sedimentation tank, the water treatment plant struggles with an inadequate and turbid water supply. This study evaluates the water treatment plant’s performance through field evaluation, interviews, and laboratory experiments, concentrating on major treatment processes to identify performance-limiting factors. The water source had an average turbidity of 29.70 ± 1.03 NTU in the dry season and 94.27 ± 16.71 NTU in the summer. Results indicate that horizontal roughing filtration, sedimentation tank, and slow sand filtration achieve average turbidity removal efficiencies of 42.02% ± 4.00%, 5.67% ± 3.15%, and 83.51% ± 8.75%, respectively, during the dry season. In the summer or wet season, these treatment units achieve efficiencies of 40.06% ± 3.26%, 28.17% ± 4.62%, and 77.07% ± 4.61%, respectively. Additionally, the average run times for slow sand filtration are 22 days in the dry season and 13 days in the summer. Total and fecal coliform removals were effective, except in the sedimentation tank. A one-way ANOVA confirms a significant difference in turbidity among treatment units. Factors such as fine filter sand particles causing faster clogging, pipe misconnections, inadequate cleaning practices, irregular filtration rates, air binding due to a lack of backfilling at startup, and a lack of periodic monitoring and emergency response lead to suboptimal turbidity removal and shorter slow sand filtration run times. The study underscores the need for corrective measures to address these issues, enhancing water treatment plant sustainability in the region.

Removal of metals and assimilable organic carbon by activated carbon and reverse osmosis point-of-use water filtration systems

Activated carbon (AC) systems and reverse osmosis (RO) systems are commonly used point-of-use (POU) water filtration systems for removing trace-level contaminants in tap water to protect human health. However, limited research has been done to evaluate their effectiveness in removing heavy metals like manganese (Mn) and uranium (U), or to assess the potential for undesired microbial growth within POU systems, which can reduce their treatment efficiency. This study aimed to systematically evaluate the removal of metals and assimilable organic carbon (AOC) in POU systems. AC systems were operated to 200% of their designed treatment capacities and RO systems were run for three weeks. The results showed that AC systems were generally ineffective at removing metals from drinking water, while RO systems effectively removed them. Both Mn and U were poorly removed by AC systems. Calcium (Ca) and magnesium (Mg) were poorly removed by AC systems, with efficiencies of less than 1%. Iron (Fe) removal by AC systems varied between 61% and 84%. Copper (Fe), likely due to its low influent concentration (<30 μg L−1), was effectively removed by AC systems with efficiencies over 95%. In contrast, RO systems consistently removed all metals effectively. Mn and U removal in RO systems exceeded 95%, while Ca, Mn, Fe, and Cu were all removed with efficiencies greater than 98%. AOC was effectively removed from all AC and RO systems, but with high variability in removal efficiency, which is likely attributed to the heterogeneity of biofilm and microbial growth within the POU systems. The new knowledge generated from this study can improve our understanding of chemical contaminant removal in POU systems and inform the development of better strategies for designing and operating POU systems to remove chemical contaminants in drinking water and mitigate their associated health risks.

Gendered farmer perceptions towards soil nutrition and willingness to pay for a cafetière-style filter system for in-situ soil testing: Evidence from Central Kenya

Soil nutrition is a key pillar in agricultural productivity. However, point-of-need testing for soil nutrition is not readily available in resource-limited settings such as Kenya. We set out to study the perceived need for soil testing among farmers in this country. A group of 547 farmers from Murang'a and Kiambu counties in central Kenya were recruited through multi-stage sampling to help assess the perceptions and willingness to pay (WTP) toward a prototype technology for surveillance of in-situ soil nutrition. The technology is based on a cafetière-style filter system for extraction and a microfluidic paper-based analytical device (μPAD) for nutrient readout. We employed the double bounded choice contingent valuation method (CVM) to analyze the willingness of farmers to accept and pay for the prototype if the technology was available on the market. It was found that currently, only 1.5 % of farmers carry out soil testing. The high costs of analysis at testing centers, which are often far from the farmers, are among the main reasons contributing to the majority of farmers not testing their soils. The farmers surveyed were generally willing to make their soil data publicly accessible, especially to extension officers. CVM showed that uncontrolled WTP had a 94.24 % premium above KSh1,000 ($6.60) incurred by using the existing rapid testing method. Factoring the control variables and disaggregating the model into gender categories, the findings showed that youth, women, and men had WTP values of KSh1,612.53 ($10.75), KSh1,558.68 ($10.39), and KSh1,504.83 ($10.03), respectively, indicating that farmers can indeed pay for the convenience to test their soils in situ. Through the democratization of soil nutrition data, extension agents can enhance the improvement of agricultural productivity, which implies that farmers can commercialize their agricultural activities.