Particulate Matter Removal Efficiency Research Articles

Combined control of PM and NOx emissions from small-scale combustions by electrostatic precipitation

Electrostatic precipitators (ESPs) have demonstrated promise in reducing particulate matter (PM) emissions, but their potential for simultaneously reducing NOx in small-scale combustion systems remains largely unexplored. This study examines the potential of ESP with DC corona discharge of negative polarity to reduce both PM and NOx emissions from small-scale combustion. A chemical kinetic model is first developed to predict NOx removal in the ESP. The model accounts for the non-uniform electric field distribution and inhomogeneity of non-thermal plasma in chemical kinetic while remaining simple enough for practical engineering applications. This allows for the optimisation of ESP parameters during the initial design phase. Using this model, the ESP was developed and applied with different energisation regimes to control emissions from a 15 kW pellet combustion heating unit. The initial concentrations for PM and NOx were 48 mg/m3 and 305 mg/m3, respectively (0 °C, 101.3 kPa; at reference O2 = 10 %vol.). The efficiency of the ESP was both theoretically and experimentally determined for various operational regimes at voltages ranging from 6.8 to 11 kV. At 11 kV, the ESP demonstrated a PM removal efficiency of 99.99 % and a NOx removal efficiency of 38 %, achieving compliance with Ecodesign Directive limits. The model's predictions showed reasonable agreement with experimental data, with a slight miscalculation for both particle precipitation and NOx removal. These findings have significant implications for the design and operation of ESPs in small-scale biomass combustion systems, offering a foundation for optimising these devices for combined NOx and particulate matter control.

Particulate matter retention and removal efficiency in ten tree species of semi-arid environment

Modern era has witnessed particulate matter (PM) become one of the biggest threats for the existence of biological species. Therefore, a study was performed in Faisalabad city to evaluate PM retention and removal efficiency of ten local tree species. Branch samples were collected from urban, sub-urban and rural areas in September 2020 (183 days after rain), and in August 2021 (30 days after rain). Results showed that total PM load, PM>10 and PM10-2.5 retention was the highest in urban followed by sub-urban and rural area. PM>10, PM10-2.5, total PM, and PM deposition rate decreased significantly in the following order, F. benghalensis > T. arjuna > S. cumini > A. scholaris > F. religiosa > E. camaldulensis > D sissoo > C lancifolius > B. ceiba > M. alba during both years 2020, and 2021. During the artificial rainfall experiment, total PM removed by the species also followed the same order however, PM removal efficiency was the highest in B. ceiba and M. alba followed by E. camaldulensis, C. lancifolius, D. sissoo, T. arjuna, S. cumini, A. scholaris, F. religiosa and F. benghalensis. Therefore, it can be concluded that species selection must be done skillfully for congested urban environment.

Fuzzy machine learning predictions of settling velocity based on fractal aggregate physical features in water treatment

The dynamics of gravitational sedimentation in water treatment are crucial for optimising particulate matter removal. This study addresses the effect of fractal aggregate features on settling velocity and explores fuzzy machine learning (ML) for predicting this phenomenon. Particle image velocimetry determined aggregate velocities within a sedimentation column, with features identified concurrently. Using a comprehensive methodological framework, significant predictors were selected through various statistical analyses. The fuzzy ML model, developed with the ‘FisPro’ package in R, incorporated a hierarchical partitioning scheme using Lukasiewicz and Sum operators for conjunction and disjunction processes, respectively. The Wang-Mendel method extracted fuzzy rules, with defuzzification achieved using the maximum crisp operator. Hyperparameter optimization was conducted through grid search techniques, and model performance was evaluated using 3-fold cross-validation. The findings reveal that Margination, Radius, and Clumpiness significantly impact settling velocity. The model demonstrates exceptional predictive accuracy (R2 = 0.923) across both training and validation datasets, highlighting its potential for forecasting terminal velocity in water treatment. This research suggests that precise predictions of sedimentation dynamics can improve particulate matter removal efficiency and encourages further investigations into diverse aggregate types and environmental scenarios, advocating for integrating physics-informed ML approaches to enhance the model.

Using DPF to Control Particulate Matter Emissions from Ships to Ensure the Sustainable Development of the Shipping Industry

PM (particulate matter) emissions from ships are the main sources of marine atmosphere pollution. Controlling the emissions of particulate matter from ships is related to the sustainable development of the shipping industry. To reduce PM emissions from marine four-stroke diesel engines, DPFs are effective. Our results show that DPF had more than 90% capturing efficiency for both the number and mass emissions of PM, and the capturing efficiency for the accumulation mode was higher than that of the nuclear mode. DPF can also significantly reduce the chemical components of PM in marine diesel exhaust gas. The removal efficiencies for OC and EC were 89.7–91.6% and 84.8–92.8%, respectively, with each particle size range showing over 80% efficiency. SO42− was the ion with the highest content, followed by NH4+, NO3−, Na+, NO2−, and Cl−, with their reduced proportions remaining consistent with the removal efficiency of particulate matter. DPF can also effectively reduce PAH content and toxicity. The use of DPF can greatly improve the impact of ship emissions on the marine atmospheric environment. The appropriate DPF with the best performance can be selected according to the exhaust parameters and particle size distributions with different characteristics.

Application of Acinetobacter indicus to promote cigarette smoke particulate matter phytoremediation: removal efficiency and plant-microbe interactions.

Particulate matter (PM) is one of the most hazardous atmospheric pollutants. Several plant species show high potential to reduce air pollutants and are widely used as green belts to provide clean outdoor spaces for human well-being. However, high PM concentrations cause physiological changes and stress in plants. In this study, 11 species of Thai native perennial plants were exposed to PM generated from tobacco smoke. Wrightia religiosa (Teijsm. & Binn.) Benth. ex Kurz, Bauhinia purpurea DC. ex Walp. and Tectona grandis L.f. reduced PM effectively (which is in the typical range of 43.95 to 52.97%) compared to other plant species. In addition, the responses of perennial plants under PM stress at the proteomic level were also evaluated. Proteomic analysis of these three plant species showed that plants respond negatively to high PM concentrations, such as reducing several photosynthetic-related proteins and increasing plant stress response proteins. To improve PM phytoremediation efficiency and reduce plant stress from PM, perennial plant-microbe interactions were investigated. W. religiosa was inoculated with Acinetobacter indicus PS1, and high biosurfactant-producing strains clearly showed a higher PM removal efficiency than non-inoculated plants (9.48, 9.5 and 12.6% for PM1.0, PM2.5 and PM10, respectively). Inoculating W. religiosa with A. indicus PS1 maintained chlorophyll a and b concentrations. Moreover, the malondialdehyde (MDA) concentration of W. religiosa inoculated with A. indicus PS1 was lower than that of non-inoculated W. religiosa. The leaf wax content (µg/cm2) and biosurfactant (µg/cm2) of W. religiosa inoculated with A. indicus PS1 were also higher than those of non-inoculated W. religiosa. This study clearly showed that inoculating plants with A. indicus PS1 can help plants remediate PM and improve their PM stress response.

Application of DBD air plasma for indoor particulate matter removal

The use of non thermal plasma (NTP) to improve indoor air quality (IAQ) has grown considerably in recent years. This paper demonstrates the advantage of NTP for IAQ improvement in terms of particulate matter (PM) removal. The PM removal mechanism using active air ions and radicals has been investigated. From the developed dielectric barreir discharge (DBD) air plasma reactor, the total PM removal efficiency of 61.72% has been achieved at an optimised concentration of negative and positive air ions in 2 hours of continuous operation. Due to the utilised sensor's limit of quantification (LOQ), PM 2.5 and PM 10 have been reduced to a certain value. The findings revealed that DBD air plasma can be effectively used for PM removal in an enclosed environment.

Removal Efficiency of Bottom Ash and Sand Mixtures as Filter Layers for Fine Particulate Matter.

Permeable pavement is a technology that allows rainwater to infiltrate into the pavement. Permeable pavements not only help reduce surface runoff by allowing rainwater to infiltrate into the pavement, but also improve water quality with the filter layer that removes particulate matter pollutants. This study evaluated the particulate matter removal efficiency of bottom ash-sand mixtures as filter layers for removing fine (≤10 μm) or ultrafine (≤2.5 μm) particulate matter in the laboratory. Five filter media were tested: silica sand, bottom ash, and bottom ash-sand mixtures with 30:70, 50:50, and 70:30 ratios. The mixed filters exhibited more consistent and stable particulate matter removal efficiency over time than either the uniform sand or bottom ash filter. The 50:50 bottom ash-sand mixture demonstrated removal rates of 58.05% for 1.8 μm particles, 93.92% for 10 μm particles, and 92.45% for 60 μm particles. These findings highlight the potential of bottom ash-sand mixtures as effective filter media for removing PM10 road dust, although field validation with actual pavement systems is necessary.

Self-synthesis and performance analysis of a Cu-Fe composite ZSM-5 zeolitic catalyst for NOx reduction and particulate matter removal using NH3 SCR

The NH3-SCR has gained widespread usage due to its exceptional denitrification efficiency. It achieves high nitrogen oxides (NOx) reduction rates within the temperature range of 300⁰C to 400℃. Nonetheless, most of the catalyst have a limited temperature range for effective NOx removal applications. For sustainable utilization of common combustion units, it has become essential to develop a catalyst which can provide a broader spectrum of temperature range for NOx reduction. This study is thus aimed to enhance the structure of ZSM-5 zeolite molecular sieves using tetrapropylammonium bromide. Copper and iron ions (total 3% weight) were incorporated to boost the reaction at temperatures of 180⁰C, 250⁰C and 320⁰C. The overall efficiency of NOx removal was above 81%, highest being 97.6%. The carrier significantly impacts the NOx conversion rate with increased copper ion content in the samples at medium and low temperatures. The Particulate Matter removal efficiency ranged from 90.1% to 93.1%.

PM2.5 Collection Enhancement in a Smart Hybrid Wet Scrubber Tower

The removal efficiency of particulate matter of less than 2.5 microns (PM2.5) using an innovative wet scrubber tower with an IoT system for PM2.5 real-time monitoring was investigated. The PM2.5 used in this experiment was obtained from vehicle exhaust, specifically from running the diesel engine of a pickup truck with a range of PM2.5 with a concentration ranging from 50 µg/m3 to 500 µg/m3. Focused parameters related to PM2.5 were analyzed, such as the liquid-to-air ratio (it uses air because this device purifies PM2.5 for the airflow from the polluted ambient air), turbulence techniques enabled by the installation of a deflector and a baffle at the airflow inlet, water level fluctuation above the nozzle, spray nozzle size, and the type of packing material. The average PM2.5 removal efficiency was determined for each parameter relevant to the experiment. The results showed that increasing the liquid-to-air ratio increased the average PM2.5 removal efficiency, while the smaller droplet spraying water resulted in higher efficiency. The spray section achieved its highest efficiency at 58.63%, with a liquid-to-air ratio of 13.21 L/m3 and droplet size of 270 µm. The turbulence technique showed a higher potential for the removal of PM2.5, with an efficiency level of 71.56% at a water level of 150 mm. Moreover, the operation incorporates water spraying and turbulence induction, promoting higher removal efficiency, from 71.56% to 87.59%, at a water level of 150 mm and a liquid-to-air ratio of 9.03 L/m3. This condition resulted in an output concentration of PM2.5 less than 15 µg/m3, which meets the WHO’s guidelines for PM2.5 intensity. This cleverly designed wet scrubber tower can clean up to 13,320 m3 of air daily or remove up to 2,464 g of PM2.5 per day. No enhancement of PM2.5 removal efficiency was observed when two types of packing materials were used due to the formation of bigger droplets as the packing materials were passed through.

Performance evaluation of particulate matter removal by surfactant foams

Surfactant foams can be repeatedly formed and ruptured, providing an extensive surface area which can be utilized for the contaminant removal. In order to mitigate the expenses associated with filter maintenance in the filter-equipped device, the particulate matter removal was attempted by the surfactant foam in this study, aiming to assess the feasibility as an alternative technology for improving air quality. Two types of particulate matter (Arizona test dust (ATD) and incense stick) and two types of surfactants (SLS-30 and LAO) were adopted to evaluate the removal efficiency of particulate matter under different surfactant concentrations (0.05, 0.1, and 0.2 wt%) and different flow systems (with and without internal airflow). Overall, ATD were better removed than incense stick due to the larger size which resulted in the greater sedimentation and subsequent contact with foams. Also, SLS-30 showed better removal performance than LAO as the surfactant concentration increased from 0.05 wt% to 0.2 wt%. These findings can be attributed to foam generation properties, in which SLS-30 demonstrated superior foam generation capabilities as the surfactant concentration increased, providing a larger surface area for PM adsorption as well as suppressing the remaining headspace in the chamber. The findings in this study presents the advantageous utilization of foams as an adsorbent for PM as well as a filling material in the limited space, thereby enabling enhanced PM removal capabilities.

Development of electrospun filter with high efficiency to reduce disturbance on gas detection in dusty environments

AbstractIn some harsh environments, certain gases are very important for the safety, such as methane gas from underground coal mines, which may explode causing catastrophic consequences. However, such gas detections are often disturbed by the particles. In this study, aiming at the scenario of underground coal mines, electrospun filters were developed and used as the pre‐filter of electronic nose (PFEN) to mitigate the disturbance on gas detection in dusty environments. Two poly (ε‐caprolactone) (PCL) filters and four poly (ε‐caprolactone)/graphene oxide (PCL/GO) filters have been prepared and compared with two commercial filters. The results shows that all filters did not affect the response of sensors to the detecting gas as compared with that without filters. The PCL/GO filter at GO concentration of 0.03% (PCL/GO‐3) had the best performance. The PCL/GO‐3 filter exhibited high removal efficiency of particulate matter (PM) with 99.27% (PM1), 99.67% (PM2.5), and 99.90% (PM10), low pressure drop of 75 Pa, and highest quality factor of 0.076 as compared with other filters. In addition, the PCL/GO‐3 filter exhibited higher tensile strength than those of other electrospun filters and commercial filters. These results indicate that the electrospun filters can be excellent option to be used as PFEN for mitigating PM deposition for gas detection in dusty environments.

Field evaluation of electrostatic precipitators for particulate matter mitigation in a manure-belt layer facility

Two full-scale electrostatic precipitators (ESPs) were tested at a commercial poultry egg production facility to assess their particulate matter (PM) removal capabilities. The smaller indoor ESP had an airflow treatment area of 0.371 m2 and operated at 26 kV, resulting in mean PM2.5, PM10, and total suspended particulates (TSP) removal efficiencies of 79.6% ± 5.7%, 92.7% ± 4.4%, and 94.6% ± 2.0%, respectively. The respective mean PM2.5, PM10, and TSP removal efficiencies for the larger exhaust ESP, which had an airflow treatment area of 0.767 m2 and was operated at 40 kV, were 93.6% ± 5.0%, 94.0% ± 5.0%, and 94.7% ± 4.4%. The indoor ESP showed greater PM2.5 and PM10 removal efficiencies in warm weather, whilst cold weather resulted in higher removal efficiencies for the exhaust ESP. The indoor ESP exhibited greater PM2.5 removal efficiencies throughout the afternoon, while PM removal efficiencies were lower during the afternoon for the exhaust ESP. Previously developed empirical models to predict weighted ESP PM removal efficiencies were calibrated to field data and successfully validated. The indoor ESP featured an initial cost of US$7,095 and an estimated annual operating cost of US$120, with a system of ESPs to treat recirculated air costing US$16,765 annually. For the exhaust ESP, the initial cost per unit was US$8,610, with an estimated annual operating cost of US$123 per unit or US$23,631 for a system of ESPs to treat exhaust air for the entire facility. Significant further research is required to quantitatively assess potential cost effectiveness for systems of multiple ESPs installed at commercial poultry facilities.

Chitosan Coating in the Form of Polymer and Nanowhiskers on Clothing Fabrics for Improved Particulate Matter Removal Efficiency in Face Mask Filters

ABSTRACT The demand for face masks is increasing exponentially due to the coronavirus pandemic and the particulate matter (PM) in the atmosphere. As a result, an enormous number of disposable mask filters have been produced and discarded, contributing to plastic waste. Underprivileged people who cannot afford to purchase commercial face masks have started making fabric masks with waste clothing; however, this material does not effectively filter viruses or PM. Therefore, in this study, a chitosan coating was applied to clothing fabrics to increase their effectiveness as face masks. The improvement in the PM removal efficiency owing to the chitosan polymer was observed for stocking, innerwear, and bamboo materials, but not for cotton. Furthermore, chitosan prepared in the form of a nanowhisker (CsW) achieved a PM 2.5 removal efficiency of 96% in a five-layer cotton fabric. In addition, a commercial biodegradable poly(lactic acid) filter was coated with CsW, which increased the PM 2.5 removal efficiency from 67% to 83%. Additionally, microbial growth was significantly suppressed in the chitosan-coated fabrics, and the degree to which it was suppressed depended on the coating concentration. The study will aid in the utilization of face mask filters that are more sustainable, efficient, and widely accessible.

Electric charge effect of micro-droplets generated by electrospray atomization on removal of indoor fine particulate matter

Airborne particulate matter (PM) can cause critical health issues due to its adverse effects on human health. Given that people usually spend more than 90% of their time indoors, controlling the mass concentration of indoor PM is very important. Although many studies on indoor PM removal have been conducted, they are mostly limited to filtration techniques. In addition, studies about practical techniques that ecan be directly applied to an indoor environment are relatively scarce. In this article, the PM removal effects of electro-charged water droplets through electrospray atomization were experimentally investigated by quantitatively monitoring the PM concentration inside a test chamber. The PM removal efficiency and the deposition constant were examined with varying electric charges of atomized water droplets, and cigarette and incense smokes were used as indoor PMs. The electric charge was measured by using a Faraday cup with an electrometer to validate the electrostatic effect on PM removal. Analytical deposition constant was obtained to evaluate the effect of electrostatic force of the charged droplets on PM removal. The analytical deposition constant was obtained based on the experimental results, such as the electric charges and mean diameter of the water droplets and the PM concentration. The analytical deposition constants were compared with the experimental ones. This electrospray system would be utilized to demonstrate its applicability in real life for effective indoor PM removal.

Electrospun Cyclodextrin/Poly(L-lactic acid) Nanofibers for Efficient Air Filter: Their PM and VOC Removal Efficiency and Triboelectric Outputs.

In this work, PLLA and CD/PLLA nanofibers were fabricated using electrospinning and utilized as a particulate matter (PM) and volatile organic compounds (VOCs) filter. The electrospun PLLA and CD/PLLA were characterized with various techniques, including SEM, BET, FTIR, XRD, XPS, WCA, DSC, tensile strength testing, PM and VOCs removal efficiency, and triboelectric performance. The results demonstrated that the best air filter was 2.5 wt%CD/PLLA, which performed the highest filtration efficiencies of 96.84 ± 1.51% and 99.38 ± 0.43% for capturing PM2.5 and PM10, respectively. Its PM2.5 removal efficiency was 16% higher than that of pure PLLA, which were contributed by their higher surface area and porosity. These 2.5 wt%CD/PLLA nanofibers also exhibited the highest and the fastest VOC entrapment. For triboelectric outputs, the 2.5 wt%CD/PLLA-based triboelectric nanogenerator provided the highest electrical outputs as 245 V and 84.70 μA. These give rise to a three-fold enhancement of electrical outputs. These results indicated that the 2.5 wt%CD/PLLA can improve surface charge density that could capture more PM via electrostatic interaction under surrounding vibration. Therefore, this study suggested that 2.5 wt%CD/PLLA is a good candidate for a multifunction nanofibrous air filter that offers efficient PM and VOC removal.

New Prospects to Systematically Improve the Particulate Matter Removal Efficiency of Urban Green Spaces at Multi-Scales

Previous studies on the removal of airborne particulate matter (PM) by plants have mostly focused on the individual scale, hence there is a lack of systematic understanding of how to improve the PM removal effect of green spaces (GS) at multi-scales. We provide new insights into an integrated model, which integrates the utilization efficiency of vertical space and time into the multi-cycle PM removal model developed in our previous study. By analyzing the variabilities of the influencing factors at different scales, directions to improve this function at multiple scales can be proposed. According to the planning of urban GS, five scales were divided. At the species scale, plants should not only have the characteristics to match the local climate, but also a high utilization efficiency of time and space. At the community scale, increasing the hierarchy and structural complexity can help improve the utilization of vertical space. At the patch and landscape scales, the factor affecting the PM removal efficiency of GS lie in precipitation frequency, and large/small green patches with low/high landscape fragmentation in climates with low/high precipitation frequency are recommended. At the urban scale, it is necessary to increase the degree of temporal and spatial distribution matching between PM and GS. These findings can improve urban GS planning to contribute to the removal of airborne PM.

A Study on the Particle Removal Efficiency and Durability According to the Material of the Ionizer of the Fiber Brush Type Electric Precipitator

In this study, we investigated the particulate matter (PM) removal efficiency and durability of the two-stage electrostatic precipitator (ESP) different materials of brush-typed ionizers (non-metal: carbon fiber/metal: stainless steel (SUS) fiber). The PM removal efficiency was reduced when the average diameter and number of fibers of the brush-typed ionizer increased due to thin and multi-edge in a large number of fibers, which decreased the average electric field, resulting in lower PM removal efficiencies. In contrast with the carbon fiber ionizer, when the SUS fiber ionizer was used, the PM removal efficiency was maintained for a long time, due to its lower electrical resistivity (∼6.9 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−7</sup> Ω * m) of the SUS fiber compared with the carbon fiber (∼5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−4</sup> Ω * m), which prevents the positive ions to be stacked on the fiber. Therefore, the present research showed the potential use to apply SUS fiber ionizers as two-stage ESPs for a future air pollution control technology with high PM removal efficiency and durability without ozone emission and additional maintenance.

Core-shell structured, mixed cellulose ester-alumina composite membranes for air filters with improved environmental resistance

In this study, a composite membrane was developed by conformally coating an ultrathin Al2O3 layer through low-temperature (90 °C) atomic layer deposition (ALD) on a hydrophilic mixed cellulose ester (MCE) membrane with a 3D networked microporous structure. The thickness of the deposited Al2O3 layer, without clogging the pores of the membrane, was precisely controlled by varying the number of ALD cycles from 100 to 300. The ultrathin (∼33 nm) Al2O3 layer greatly enhanced the resistance to various environmental stimuli and contributed to the improved removal efficiency of airborne particulate matter (PM), owing to the reduced pore size. The resulting composite membrane installed on an insect screen exhibited excellent removal efficiency (>99%) for PM of various sizes (PM1.0, PM2.5, and PM10) at a controlled flow rate of 1 L/min. In particular, unlike polypropylene-based commercial PM filters that strongly rely on electrostatic adsorption for PM filtration, the reduction in the PM removal efficiency caused by water or ethanol was negligible in the developed composite membrane, enabling long-term use even in extreme environments.

A novel multi-gradient PASS nanofibrous membranes with outstanding particulate matter removal efficiency and excellent antimicrobial property

Air pollution, especially tiny pollutant particles and harmful microorganisms, has become a serious environmental issue, bringing great damage to human body. Air filtration has been a widely used and effective method for air purification. However, the addition of antimicrobial agents usually leads to the agglomeration and the toxicity of the filter material. Here, a versatile poly (aryl sulfide sulfone)/graphene oxide@silver (PASS/GO@Ag) air filtration membrane was fabricated by in-situ reduction and electrospinning approach, resulting in high filtration efficiency and excellent biocompatibility. The results showed that GO@Ag antimicrobial agent was successfully synthetized. The Ag nanoparticles (NPs) on the GO surface not only increased the antimicrobial property but also reduced the agglomeration of the antimicrobial agent. Meanwhile, GO@Ag was wrapped on the surface of the PASS nanofibers by ultrasonication to form a rough surface to further improve the filtration efficiency. The as-prepared PASS/GO@Ag membrane exhibited high air filtration performance (99.63 ± 0.34 %, 79.17 ± 1.07 Pa). Besides, it also showed excellent antimicrobial properties and good biocompatibility. The antibacterial rates of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were 99.57 ± 1.04 % and 97.93 ± 1.31 %, respectively. More importantly, the PASS/GO@Ag membrane could endow long-term use for one month, with the antibacterial rates of E. coli and S. aureus of 96.52 ± 1.20 % and 94.48 ± 1.13 %, respectively. Therefore, the developed membrane will have great potential for personal air filtration.

An in situ self-charging triboelectric air filter with high removal efficiency, ultra-low pressure drop, superior filtration stability, and robust service life

Applying air filters is a practical approach to protecting people from particulate matter (PM) pollution. However, high pressure drop or removal efficiency decay remains a considerable challenge for existing air filters while maintaining desirable removal efficiency. Generating charges by TENG technology is one of the significant advances for high-efficiency air filters. While TENG-based air filters usually require an additional TENG to achieve high removal efficiency that is only effective during TENG operation, resulting in increased redundancy and complexity of filters for practical applications. Using nonwoven carding and through-air bonding techniques, here we report an in situ Self-charging Triboelectric Air Filter (S-TAF) consisting of silica nanoparticles modified polytetrafluoroethylene (PTFE) fibers and polypropylene/polyethylene (PP/PE) core-shell fibers. The S-TAF can be bipolarly charged in situ due to the triboelectrification effect between fibers during the carding process, thus dramatically enhancing the PM removal efficiency by electrostatic attraction. The unique core-shell structure of PP/PE fibers and the application of the through-air bonding process endowed the filter with a fluffy structure, high porosity, and large pore size, enabling the S-TAF with ultra-low pressure drop and robust service stability. Notably, the removal efficiency and quality factor (QF) of the S-TAF reached 99.28% and 0.19 Pa−1, and the pressure drop was only 26.46 Pa. Besides, the S-TAF also exhibited superior charge and filtration stability. Our unique design of the S-TAF may provide a new direction for fabricating high-performance air filters with integrated properties of high removal efficiency, ultra-low pressure drop, superior QF and filtration stability, and robust service life.