Performance Of Filter Media Research Articles

Effect of pre-cladding dust layer on filtration and pulse-jet cleaning performance of filter media

Pleated cartridge with triangular structure is prone to clogging when filtering sticky dust, leading to a significant reduction in filtration capacity. In this paper, a method of pre-cladding low-viscosity dust was introduced to promote the filtration and cleaning performance on sticky dust. The adhesion of six types of dusts was tested by both reverse blowing and pulse-jet cleaning. The effect of dust feeding rate, filtration velocity and pre-cladding pressure drop on the dust layers was investigated. Through comparative tests, the cleaning cycles reduce rates of two loading methods were 45.99% and 15.89%, while dust emission concentrations were 1.83 and 2.03 mg/m3, which reveals that the pre-cladding method can increase the filtration efficiency in the early stage and improve the cleaning performance. The increased pressure drop with hybrid and pre-cladding methods under two times cleaning process were 8.8, 15.8, 8.4 and 14.8 Pa, which demonstrated that hybrid method is applicable in industrial application. This study is aiming to provide an efficient filtration and cleaning method to avoid clogging during filtering sticky dust.

Performance Evaluation of Various Filter Media for Multi-Functional Purposes to Urban Constructed Wetlands

The escalating demand for innovative solutions is driven by the challenges posed by water quality degradation and the pervasive impacts of climate change. As such, this study evaluated the performance of filter media to mitigate these challenges through multi-functional applications in urban constructed wetlands (UCWs). Column testing of organic filter media, including biochar (BC), woodchip (WC), anthracite (AT), and activated carbon (AC), as well as inorganic filter media, such as ceramic balls (CB), basalt (BS), and porous sand (PS), with synthetic stormwater runoff influent was conducted to assess their performance through water quality parameters and Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) analysis for carbon storage potential. Among the media tested, AC exhibited high pollutant removal efficiencies amounting to 84%, 54%, 56%, and 44% for total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP), respectively. For inorganic media, PS had the highest TSS and TN removal, whereas BS exhibited the highest COD and TP removal. Overall performance rating revealed that AC and BS, despite their efficient pollutant removal, are associated with higher costs, resulting in a lower ranking compared to AT and PS. SEM-EDX analysis identified PS and AC as standout media for potential carbon storage, attributed to their extensive surface areas and pore structures providing abundant adsorption sites. The results from this study highlighted the potential applications of various filter media in UCW designs with the aim of achieving carbon neutrality and sustainable urban development.

Impact of progressive pulse cleaning pressure on polyester filter media performance using pulse jet filtration test rig

Impact of progressive pulse cleaning pressure on polyester filter media performance using pulse jet filtration test rig

Experimental Study of the Effect of Humidity on Air Filter Material Performance

A large number of application cases show that air filter media are easy to fail under extreme conditions of high humidity, haze, rain and snow, thus seriously affecting the energy efficiency of gas turbines. To study the impact of humidity on the dust-holding performance of filter media, three typical filter media applied for gas turbines with a similar efficiency are selected, and their dust-holding performance is investigated at a humidity of 30%, 60% and 75%, respectively. The results showed that the dust-holding pressure drop curves of three filter media were divided into two phases. With the increase of humidity, the increasing pressure drop rate of three filter media decreased. The pressure drop synthetic fiber, glass fiber composite filter media and the synthetic fiber composite filter media with a sandwich structure were more significantly affected by humidity during the filter cake filtration phase. Under the same conditions, filter media with a sandwich structure had the highest dust-holding capacity, while the electrospun fiber composite filter material had the lowest one. The dustcake formed on the surface of the filter media that consist of a pure synthetic fiber or a small amount of plant fiber is significantly affected by humidity.

Effects of various humid environments on the filtration and dust cleaning performance of filter media

The filtration technology is gaining popularity in underground projects which are characterized by a poor working environment. However, the influence of various humid environments on the filtration performance of filter media (FM) has not been clarified yet. This study is the influence of humid environments on the performances of common mechanical filter media (MFM) and polytetrafluoroethylene coated filter media (CFM). First, the methods to control the dust moisture content, relative humidity and spray rate were determined. Then, the influences of dust loading on the pressure drop, filtration velocity and dust cleaning performance in various humid environments were explored. The results indicate that the maximum pressure drops of MFM and CFM both grow first and then decline with the increase in dust moisture content. The different is that the maximum pressure drops of MFM and CFM both decrease with the rise of relative humidity. In addition, the maximum pressure drops of MFM and CFM both decline first and then rise with the acceleration of the spray. Under the same humid environment, MFM correspond to a larger maximum value and a greater variation of pressure drop than CFM. When the dust moisture content, relative humidity or spray rate increases, the residual pressure drops of both FM grow after dust cleaning, but the latter corresponds to a smaller growth.

Effect of rolling point accounting for 33% on the filtration performance of fibrous filter media

This study investigates the effect of rolling points accounting for 33% on the filtration performance of filter media, hoping to provide guidances for the selection of filter media for industrial dust removal. The differences in filtration performance between filter media with and without rolling points were compared through experiments. The results show that the initial pressure drop and resistance coefficient of clean filter media with rolling points increase by 31.07% and 45.08%, respectively. And, the pressure drop of loaded filter media with rolling points and the specific resistance coefficient of the dust cake are improved, but the difference in filtration efficiency between the two filter media not exceed 5%. Compared with the rolling points area accounting for about 33% of the physical filtration area, the effective filtration area of filter media without rolling points is 39.52% larger on average. Compared with the filter media with rolling points, the average filtration efficiency of the filter media without rolling points decreased from 91.90% to 89.88%, but the average pressure drop decreased from 128.7 Pa to 85.1 Pa, and the quality factor increased from 0.01637 to 0.02161, an improvement of about 32.01%. In short, rolling points reduce the filtration performance of filter media, and filter media without rolling points have better filtration and energy consumption performance.

Effect on Efficiency of Air Filter Element at Steady and Dynamic Condition

Abstract: For the better protection of the engine, required highly efficient air. Primary feature of engine air filter element is the dust holding capacity, in the parameters major factor is efficiency when we are selecting an engine air filter media or element. For deliver higher filtration performances constantly being challenge in automotive engine air filters. There is need to protect the engine from dust particle which effects on the performance and life of the engine, abrasive contaminants are increasing to achieve longer engine life, for improved engine performance. The innovative air filter designs are required to maximize filtration property and better performance. The performance of the engine as well as life of the engine are based on filtration efficiency of air filter. In this study we are discussed about filtration efficiency of the air filter. In this experiment we study the effect of the vibration on the air filter media performance as compare with the steady performance of the air filter media or assembly at steady condition. One is at steady condition and second is dynamic condition. Both tests are performing in the laboratory according to ISO5011 standard. Keywords: Air Filter, Filtration, Performance, Vibration, Air Filter Media.

Synthesis and characterization of air filter media made from cellulosic ramie fiber (Boehmeria nivea)

At present, air filter materials are predominately made of synthetic polymers that are derived from petroleum. The production of these synthetic polymers negatively impacts the environment as well as entailing complex equipment and high production costs. Thus, air filter media made from natural fiber would have a significant benefit. The research done in this study supports the use of an alternative air filter media that is easily and cheaply made from the ramie plant (Boehmeria nivea), which grows the world over. This paper explains the method used to produce fiber from the ramie plant that can be used as an air filter media, based on the T205 standards of the Technical Association of the Pulp and Paper Industry (TAPPI). The research shows that ramie fiber can be successfully used as an air filter media as it meets all of the performance standard test requirements of air filter media; it has a tensile strength of 0.36±0.03 kN/m and can withstand degrading up to the temperatures of 280 °C. Ramie fiber also has an air filter media performance of PM2.5, and a 46% efficiency rating at a pressure drop of 167 Pa.

Study on a Novel Filter Media Incorporating with Core Shell Nanoencapsulated Phase Change Material: Fabrication and Evaluation

Thermal performance of filter media plays a significant effect on the filtration efficiency of baghouse, especially its tolerance of high temperature air and chemical erosion. In this study, nano-encapsulated phase change material within the silica shell (NPCMs) is synthesized through a self-assembly method based on polymer—hyperbranched precursor polyethoxysiloxane (PEOS). Filter media is fabricated by NPCMs through a facile dip-dry-cure process to enhance its thermal regulation and serving durability. Filter media acts as frame-supporting of the functional structure NPCMs. Incorporating NPCMs into filter media optimizes the microstructure and filtration efficiency of baghouse. The penetration rate was reduced from 457 × 10−4% of the control filter media to 5 × 10−4%. Meanwhile, the novel filter media lowers the temperature up to 20 °C than the surroundings. The novel filter media exhibits not only better mechanical properties, but also much less tensile strength loss after suffering 100 thermal shock cycles with simultaneous chemical exposure, from 37.58% to 20.37%. Overall, the filter media incorporated with NPCMs demonstrates excellent performances on filter efficiency, thermal regulation, and environmental endurance, which has the potential for extending lifespans and enhancing operation stability of filter bags in industrial air pollutant control.

Effectiveness of face masks for the population.

Health authorities and organizations consider non-medical face masks as an additional passive means to prevent virus diffusion. Communication strategies disseminate information among the population that such masks are essential for mitigating virus diffusion. However, scientific studies are not conclusive in showing the undisputed filtration efficiency of fabric/cloth facial masks (both commercial and homemade). This study examines scientific data about the effectiveness of face masks before and during the COVID-19 emergency. Present trends in the making of commercial and homemade fabric/cloth face masks are also examined. Statistical data of published studies are analyzed and compared. Main considerations and sugge-stions are also extracted and discussed. Current approaches are examined for assessing the characteristics and effectiveness of fabric/cloth commercial and homemade face masks intended for the population. Conflicting data exist as to whether non-medical masks have a protective effect from the spread of respiratory viruses. Both medical masks (MDs) and respiratory personal protection equipment (PPE) show a given effectiveness value. Concerning commercial and homemade fabric/cloth masks, giving general indications on the choice of materials and their assemblage is difficult as it is not possible to assess the effectiveness of the filter media with respect to the kind of multiphase fluid that may be emitted upon breathing, sneezing, or coughing under different environmental conditions. This is particularly important because airflow rate, temperature, humidity, and duration of use will affect the performance of filter media. Moreover, while a mask may have excellent filter media, droplets may leak into the face-piece unless there is an adequate facial seal. In the presence of leaks, any type of mask may actually offer less protection independently of its nominal filtering effìciency.

Impact of multilayering on the filtration performance of clean air filter media

AbstractFibrous filter media are commonly used to remove airborne particles that are harmful to human health and the environment. Although filter media are often multilayered for various reasons, no systematic study of the impact of multilayering on filter media performance has been reported. In this paper, direct numerical simulations with the lattice Boltzmann method are used in order to shed light on the impact of multilayering on the performance of clean bimodal fibrous filter media in a Stokes flow regime. Virtual model clean filter media with up to eight layers and various fibre formulations are compared in terms of permeability or pressure drop, capture efficiency, and quality factor. A careful analysis of the results revealed that multilayering had no statistically significant impact on the performance of the clean filter media. At best, the impact of multilayering was similar to that of the inherent variability of such random structures. Fibre formulation was found to be a more efficient way of improving the performance of the filter media. Placing interlayered air gaps between fibrous layers also slightly improved the quality factor by facilitating the flow at the interfaces of the fibrous layers. These findings will guide future studies on the performance of multilayered filters with more complex flow conditions, such as those encountered with inertial or nanofibre‐made filter media and with the fouling of filter media.

Separation of Water in Diesel Using Filter Media Containing Kapok Fibers.

Traditional water-repellent filter media for water separation in diesel fail to meet requirements due to the high content of surfactants in low sulfur diesel and ULSD (ultra low sulfur diesel). To improve the water separation performance of filter media, a novel dual-layer filter medium was prepared by hydrophilic fibers (glass microfibers) and hydrophobic fibers (kapok fibers and bi-component PET fibers). The results showed that the separation efficiency of a filter medium (sample #2) with the upstream layer containing 20 wt% kapok fibers was 89.5%, which was higher than that of filter samples with the upstream layer containing 0 wt%, 40 wt%, 60 wt% and 80 wt% kapok fibers. When the interfacial tension (IFT) of water in diesel was 21 mN/m, 17 mN/m and 13 mN/m, the separation efficiency of filter sample #2 was 99.5%, 89.5% and 30.5%, respectively, which was 23.9%, 57.4% and 17.8% higher than that of the commercial water-repellent filter samples composed of a polybutylene terephthalate (PBT) fiber layer and cellulose fiber layer.

Influence of relative humidity on HEPA filters during and after loading with soot particles

One of the most frequently used methods to purify air contaminated by particles, in many industrial processes, is filter media. Although the performance of filter media is relatively well documente...

Rainwater Harvesting Potential and Utilization for Artificial Recharge of Groundwater Using Recharge Wells

This study devised a practical solution to mitigate urban inundation and artificial recharge of groundwater using recharge wells which is the most viable surface runoff rainwater harvesting (RWH) technique in urban areas. The Rainwater Harvesting Pilot Project at Gaddafi Stadium Lahore was established to deal with urban flooding, artificial recharge of groundwater, and to avoid the mixing of rainwater in municipal sewerage. The study showed that Lahore city has great RWH potential from critical ponding roads that can be utilized to recharge the Lahore aquifer. With that ratio of recharge, the groundwater level can rise to 3.54 ft after every monsoon period if the same recharge wells structure are used, which is a key to groundwater sustainability in Lahore city. Moreover, the maximum recharging capacity of wells was 29.32 m3/h with satisfactory performance. Both recharge wells cleared the ponding volume within 3 to 3.5 h after the rainfall stopped. The filter media performance was also favorable with 25%–30% removal of contamination. All the water quality parameters were within the permissible limit against prescribed standards except coliform count that indicated the presence of sewage. In such a case the mixing of charcoal is recommended to shut up the coliform signals. This study identified that RWH using recharge wells is an alternative freshwater supply source for sustainable development of Lahore city and this technique should be the part of Master Planning and Policy Decision of Lahore as a suggestion.

Filter media performance under the oscillating flow condition

This work investigated the performance of two mechanical glass-fiber and one electret filter media under the oscillating flow conditions (i.e., cyclic flows in this study). DMA-classified particles of 30, 50, 100 and 150 nm, and oscillating flow conditions with the Average Suction Flow Rates (ASFRs) of 6.4, 25.6 L/min and oscillating frequency of 6, 24, 40 min−1 were chosen for the experiments. It is found in general the particle penetration of test media increases with the increase of oscillating frequency. The above-observed penetration enhancement is found to be more pronounced for small particles (i.e., 30 and 50 nm) as compared to that for large particles (i.e., 100 and 150 nm). At the flow oscillating frequency of 24 and 40 min−1, the particle penetration through filter media is also higher than it under the corresponding constant flow conditions. The increase of ASFR increases the particle penetration of filter media for all the selected particle sizes. The apparent single fiber efficiency for media A and B under cyclic flow conditions was lastly found. The obtained efficiency enables the single fiber theory to calculate the average penetration of diffusive particles through mechanical filter media under the cyclic flow conditions.

Analyzing filter media performance

Many filter media manufacturers base their results on different testing methods. Results vary accordingly with the different approaches offering different results. This article looks at the performance correlation of a flat filter media test rig and a real time pulse jet filtration process.

Performance comparison of anthracite filter media of different origin in the removal of organic traces from copper electrolyte

Eight anthracite granule species used as filter media were tested for organic phase separation from copper electrolyte in a filter bed. The effects of filter bed depth and fluid velocity were studied. The macro porosity, density, surface area, bed expansion, pressure loss during backwash, mechanical strength, surface micro porosity and morphology of the anthracite species were analyzed. The organic droplet average diameter and zeta potential of the electrolyte suspension were also measured. In addition, SEM analysis was used to investigate aging and separation performance of filter media. For the different anthracite species, the aging and a similar separation performance were found. However, some variation in performance was detected during backwash experiments. Pilot scale runs with inversed flow indicated that testing of the anthracite species before selection is advantageous.

Laboratory comparison of relative performance of gas phase filtration media at high and low O3/NO2 challenge concentrations (ASHRAE RP-1557)

To guide the selection and design of air filter/cleaning devices for improving indoor air quality (IAQ), it is important to be able to assess the performance and characteristics of filter media within a reasonable/practical testing period for low concentration conditions (∼50 ppb) under which they are applied. Our study objectives were to investigate whether filter media showing good performance at high concentrations per ASHRAE Standard 145.1 (ASHRAE 2008) would also perform well at low concentrations, typically indoors, and to explore whether and how existing models for filtration media beds can be applied to predict and extrapolate the experimental performance results obtained under high concentrations. Six filter media having different filtration properties, pellet shape and size, and target compound were selected for this investigation. Experiments were performed at both high (∼1 ppm/100 ppm) and low (∼50 ppb) levels of O3/NO2 concentration for all media selected. Existing models were evaluated for the feasibility of data extrapolation from high to low concentration conditions. The results showed that (1) the relative performance of filter media at high concentration was qualitatively indicative of that from the low concentration results and (2) no existing models were suitable for any media having major catalytic removal characteristics for the cases studied, and an improved mechanistic model needs to be developed.

Evaluation of filter media performance: Correlation between high and low challenge concentration tests for toluene and formaldehyde (ASHRAE RP-1557)

To guide the selection of gas phase filtration media in the air cleaning devices, it is important to understand and estimate the media performance under usage concentrations. Filters for improving indoor air quality are typically subject to low volatile organic compounds (VOCs) concentration levels (e.g., ∼50 ppb), while the current standard tests per ASHRAE 145.1 (ANSI/ASHRAE 2008). are performed at relatively high challenge concentrations (∼1–100 ppm level). The primary objective of this study was to determine if media that perform well at the high concentration test condition would also perform well under the low concentration. The secondary objective was to investigate if and how existing models of filtration by media bed can be applied to extrapolate the results from the high concentration tests to the low concentration condition. Experiments and simulations were carried out at both high concentrations (100 ppm for toluene and 1 ppm for formaldehyde) and low concentrations (0.05 ppm for toluene and formaldehyde) for six selected filtration media. The results show that (1) the high concentration test data were able to differentiate the relative performance among the media at the low concentration properly, confirming the validity of using ASHRAE 145.1 (ANSI/ASHRAE 2008) for relative performance comparison; (2) significant initial breakthrough observed at high concentration tests of large pellet media was not present at the low concentration tests, indicating the dependency of the adsorption capability of the sorbent media on the concentration level as well as the possible “by-pass” effects (i.e., not all the VOC molecules in the air stream had the same chance to contact with the sorbent media); and (3) existing models need to be improved by incorporating the concentration dependency of the partition coefficient and the by-pass effect in order to predict the breakthrough curve at low concentrations properly. Such an improved model was proposed, evaluated with the measured data, and was found to be promising for physical sorbent, but requires further development for chemical, catalytic sorbent and large pellet sorbent. The study provides previously unavailable experimental data and new insight into the behavior of the filtration media for volatile organic compounds as well as evidence in support of the application of ASHRAE Standard 145.1 (ANSI/ASHRAE 2008) for media performance evaluation.

Seawater biofiltration pre-treatment system: comparison of filter media performance

Biological filtration is an effective pre-treatment method to remove organic matter and particulate matter from seawater. Three biofilter columns were operated packed with granular-activated carbon (GAC), anthracite and sand as a filter media. The biofilters were run for 120 d at a slow filtration velocity of 0.12 m/h. Biofiltration performances were evaluated in terms of turbidity, different fouling indices, and dissolved organic carbon(DOC). The removal efficiencies of turbidity by the three biofilters were similar with low headloss development. The fouling potential of treated seawater (filtrate) was evaluated using three different fouling indices such as microfiltration, ultrafiltration, and microfiltration at a cross flow. The analyses of three different fouling indices showed that the reduction in fouling potential was the following order GAC ##xgt; sand ##xgt; anthracite. In terms of DOC removal efficiency, GAC biofilter showed higher and stable removal efficiency (41–88%), than sand biofilter (7–76%) and anthracite biofilter (3–71%). All biofilters used in this study removed most of hydrophobic organic compounds (around 94%). On the other hand, hydrophilic organic removal varied depending on the media filter. GAC biofilter removed more organic biopolymers (51%), humic substances (75%) and building blocks (50%) compared with sand and anthracite biofilters. Therefore, GAC biofiltration can be used as an effective pre-treatment to alleviate organic fouling.