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AbstractThe characteristic of the spiked electrode electrostatic precipitator was numerically studied. The spiked electrode had significant effects on the distribution of electric field and charge density. The electric field and charge density were quite high in the area around the spiked electrode tips while decreased rapidly in other area far from the tips. Complicated electrohydrodynamic flow was observed and strong vortices were formed in the upstream and side areas of the spiked electrode. The gas velocity at the tip of the spiked electrode was as high as 28.1 m/s at the working potential of 45 kV. The working potential was more effective for the removal of large particle. The removal efficiency increased 42.4% for 10 µm particle and 15.2% for 0.25 µm particle as working potential increased from 22.5 kV to 45 kV. Low gas velocity was beneficial to the removal of all size particles. The removal efficiency increased by 10% to 15% for all size particles when the gas velocity decreased from 1.0 m/s to 0.6 m/s. [ABSTRACT FROM AUTHOR]

Electrostatic precipitators (ESPs) have shown promise in reducing particulate matter (PM) emissions, but their potential for simultaneous NOx reduction in small-scale combustion systems remains underexplored. This study focuses on using non-thermal plasma generated in a corona discharge to reduce PM and NOx emissions from small-scale combustion. ESP was specifically designed for a commercially available 15 kW boiler with wood pellet combustion and used with both positive and negative discharge polarity to control emissions without any chemical additives. ESP performance was evaluated across a range of specific input energies (SIE) in terms of particle mass and number concentrations and NOx concentrations obtained by continuous gas analysis. ESP ensured the reduction in PM concentrations from 48 mg/m3 to the magnitude of PM content in the ambient air. The highest precipitation efficiency was observed for particles in the 20–200 nm range. Concurrently, NOx emissions were reduced by up to 78%, from 178 mg/m3 to 39 mg/m3. These results were achieved at specific input energies of 36 for positive and 48 J/L for negative corona, which is significantly lower than those reported for many existing separate PM and NOx control systems. This study demonstrates the potential of ESPs as a compact, energy-efficient solution for simultaneous PM and NOx removal in small-scale combustion systems, offering promising implications for improving air pollution control technologies for small-scale combustion systems. [ABSTRACT FROM AUTHOR]

Aerosol particle charging is widely used in various technical applications. A model of a needle-plate type charger for efficient charging of aerosol nanoparticles in a corona plasma discharge has been developed and investigated. The main difference from similar devices in the modernization of the grounded plate hole's geometry and the number of corona needles exist. This has resulted in a substantial increase in the charger's efficiency by over 25%. The effects of two types of discharge plates, one with cylindrical and the other with conical inner holes, on the extrinsic charging efficiency of aerosol particles were experimentally investigated. Metallic nanoparticles of Ag with sizes ranging from 20 to 160 nm and a number concentration of 106 to 108 cm-3 were utilized as the test aerosol. This system shows that the maximum efficiency of particle charging is attained by using a plate with a conical hole, which reduces electrostatic losses from 37±3% to 20±2%. Furthermore, an additional effect of increasing the particle charging efficiency was also observed by using a multi-pointed needle, which resulted in lower electrostatic losses compared to a single needle. Experimental evidence confirms that utilizing a conical hole in the plate and a multi-pointed needle has increased the particle charging efficiency from 47±3% to 59±4%, as opposed to the standard design featuring a cylindrical hole and a single-pointed needle. In this paper, an increase in the efficiency of charging particles in a charger with a multi-pointed needle compared to a single-pointed one is shown for the first time. [ABSTRACT FROM AUTHOR]

The objective of this study is to systematically investigate not only the influence of different additive types—beyond the much-considered case of aluminum-silicate-based additives—but also to carry out an additional comparison between primary and secondary emission mitigation measures during small-scale wood-chip combustion. Hence, combustion trials are realized within a 33-kW combustion plant. Pine wood chips additivated with 1.0 wt%a.r. of four additives have shown promising emission reduction effects in the past; namely kaolin (i.e., aluminum-silicate-based), anorthite (i.e., aluminum-silicate- and calcium-based), aluminum hydroxide (i.e., aluminum-based), and titanium dioxide (i.e., titanium-based). In addition to the primary mitigation measure (i.e., (fuel) additivation), an electrostatic precipitator (ESP) as a common secondary mitigation measure for total particulate matter (TPM) reduction is used for comparison. In addition to standard analyses (e.g., gravimetric determination of TPM emissions), an extended methodology (e.g., characterization of the elemental composition and ultrafine particle fraction of TPM emissions) is applied. The results show that the additivation of wood chips with kaolin and anorthite can lead to an operation of the combustion plant in compliance with the German legal TPM limit values by undercutting the absolute emission level achievable by the ESP. Additionally, kaolin and anorthite achieve significant reductions in carbon monoxide (CO) emissions, while kaolin simultaneously, and similarly to ESP, also leads to a shift in the particle size number distribution of PM emissions towards coarser particles. All additives show a significant reduction of potassium (K) emissions by the formation of high-temperature stable K compounds in the resulting ashes. [ABSTRACT FROM AUTHOR]

The electrodes of industrial electrostatic precipitators degrade as a result of two phenomena: corrosion and erosion. The first is chemical degradation by highly reactive compounds formed during combustion, in particular, during the incineration of municipal or industrial wastes or high-sulfur coal. The degradation intensity of electrostatic precipitator electrodes depends on the chemical composition of the exhaust gasses. High concentrations of chlorides, fluorides, or sulfur in the exhaust gasses cause strong corrosion of the electrostatic precipitator elements. The second mechanism is the erosion caused by solid particles conveyed by the exhaust gas stream due to their collision with the electrodes. In this study, the analysis of the degradation of electrodes of an electrostatic precipitator downstream of an industrial waste incinerator was carried out. The industrial wastes of unknown sources were subjected to thermal degradation in a rotary kiln. The aim of this study was to provide fundamental knowledge about the mechanisms of electrode degradation located on the surface of discharge electrodes of electrostatic precipitators during the combustion of industrial wastes. [ABSTRACT FROM AUTHOR]

Despite best efforts in air purification, airborne infectious diseases will continue to spread due to the continuous emission of bioaerosols by the host/infected person. Hence, a shift in focus from air purification to bioaerosol inactivation is urgently needed. To explore the potential of the cold plasma technology for preventing rapid spread of airborne infectious diseases, we studied a cold plasma ionizer (CPI) device and an electrostatic precipitator (ESP)-coupled CPI (CPI-ESP) device for the inactivation and cleaning of surface-spread microorganisms and bioaerosols, using porcine respiratory coronavirus (PRCV), Escherichia coli (E. coli), and aerosolized E. coli as representatives. We firstly demonstrated that CPI coupled with ESP is an effective technology for inactivating virus and bacteria spread on surfaces in an in-house test chamber. We then demonstrated the efficacy of CPI-coupled ESP for the inactivation of aerosolized E. coli in the same chamber. Furthermore, we have demonstrated the efficiency of a CPI-ESP coupled device for the inactivation of naturally occurring airborne microbials in a few indoor settings (i.e., a living room, a discussion room, a schoolroom, and an office) to determine the treatment duration- and human activity-dependent efficacy. To understand the disinfection mechanism, we conducted a fluorescence microscopy study to reveal different degrees of E. coli bacteria cell membrane damage under CPI treatment. [ABSTRACT FROM AUTHOR]

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.

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There is still a deficiency in the field of closedloop wireless control systems in terms of full real-time implementation and actualization. This paper explores the architecture, design, and implementation of Wireless Networked Control Systems (WNCS), emphasizing their operational problems. In particular, it investigates the implementation of an XBee platform-enabled Wireless Networked Control System to control an Electrostatic Precipitator (ESP) model using PC connection. The architecture of this control system is client-server. A realworld case study about the planning, creation, and implementation of a wireless monitoring control system for ESP is carefully scrutinized and assessed. The True time 1.5 simulator is used to illustrate simulation results, which provide insight into how different system factors affect overall performance and stability. The article also highlights how to use Matlab and Simulink capabilities to improve ZigBee network utilization for comprehensive feedback WNCS. [ABSTRACT FROM AUTHOR]

Electrostatic precipitators (ESPs) have shown promise in reducing particulate matter (PM) emissions, but their potential for simultaneous NOx reduction in small-scale combustion systems remains underexplored. This study focuses on using non-thermal plasma generated in a corona discharge to reduce PM and NOx emissions from small-scale combustion. ESP was specifically designed for a commercially available 15 kW boiler with wood pellet combustion and used with both positive and negative discharge polarity to control emissions without any chemical additives. ESP performance was evaluated across a range of specific input energies (SIE) in terms of particle mass and number concentrations and NOx concentrations obtained by continuous gas analysis. ESP ensured the reduction in PM concentrations from 48 mg/m3 to the magnitude of PM content in the ambient air. The highest precipitation efficiency was observed for particles in the 20–200 nm range. Concurrently, NOx emissions were reduced by up to 78%, from 178 mg/m3 to 39 mg/m3. These results were achieved at specific input energies of 36 for positive and 48 J/L for negative corona, which is significantly lower than those reported for many existing separate PM and NOx control systems. This study demonstrates the potential of ESPs as a compact, energy-efficient solution for simultaneous PM and NOx removal in small-scale combustion systems, offering promising implications for improving air pollution control technologies for small-scale combustion systems.

Despite best efforts in air purification, airborne infectious diseases will continue to spread due to the continuous emission of bioaerosols by the host/infected person. Hence, a shift in focus from air purification to bioaerosol inactivation is urgently needed. To explore the potential of the cold plasma technology for preventing rapid spread of airborne infectious diseases, we studied a cold plasma ionizer (CPI) device and an electrostatic precipitator (ESP)-coupled CPI (CPI-ESP) device for the inactivation and cleaning of surface-spread microorganisms and bioaerosols, using porcine respiratory coronavirus (PRCV), Escherichia coli (E. coli), and aerosolized E. coli as representatives. We firstly demonstrated that CPI coupled with ESP is an effective technology for inactivating virus and bacteria spread on surfaces in an in-house test chamber. We then demonstrated the efficacy of CPI-coupled ESP for the inactivation of aerosolized E. coli in the same chamber. Furthermore, we have demonstrated the efficiency of a CPI-ESP coupled device for the inactivation of naturally occurring airborne microbials in a few indoor settings (i.e., a living room, a discussion room, a schoolroom, and an office) to determine the treatment duration- and human activity-dependent efficacy. To understand the disinfection mechanism, we conducted a fluorescence microscopy study to reveal different degrees of E. coli bacteria cell membrane damage under CPI treatment.

The objective of this study is to systematically investigate not only the influence of different additive types—beyond the much-considered case of aluminum-silicate-based additives—but also to carry out an additional comparison between primary and secondary emission mitigation measures during small-scale wood-chip combustion. Hence, combustion trials are realized within a 33-kW combustion plant. Pine wood chips additivated with 1.0 wt%a.r. of four additives have shown promising emission reduction effects in the past; namely kaolin (i.e., aluminum-silicate-based), anorthite (i.e., aluminum-silicate- and calcium-based), aluminum hydroxide (i.e., aluminum-based), and titanium dioxide (i.e., titanium-based). In addition to the primary mitigation measure (i.e., (fuel) additivation), an electrostatic precipitator (ESP) as a common secondary mitigation measure for total particulate matter (TPM) reduction is used for comparison. In addition to standard analyses (e.g., gravimetric determination of TPM emissions), an extended methodology (e.g., characterization of the elemental composition and ultrafine particle fraction of TPM emissions) is applied. The results show that the additivation of wood chips with kaolin and anorthite can lead to an operation of the combustion plant in compliance with the German legal TPM limit values by undercutting the absolute emission level achievable by the ESP. Additionally, kaolin and anorthite achieve significant reductions in carbon monoxide (CO) emissions, while kaolin simultaneously, and similarly to ESP, also leads to a shift in the particle size number distribution of PM emissions towards coarser particles. All additives show a significant reduction of potassium (K) emissions by the formation of high-temperature stable K compounds in the resulting ashes.

An electrostatic precipitator (ESP), which filters the fine particles present in the exhaust gas generated from a power plant, has a better particle-collection efficiency when there exists a uniform flow in the dust collection chamber. However, most former investigations examined the flow distribution via numerical approaches that modeled the perforated plates within the inlet diffuser as porous media, which have not been adequately validated. Therefore, the aim of this study was to examine the performance of the porous media model for simulating the flow through perforated plates of an ESP diffuser by numerical simulation and experiment. Simulation results using the porous media model were compared with those obtained with a fully resolved mesh precisely describing the complete geometry of the entire perforated plate. The results obtained with both these methods were consistent with experimental results obtained upstream of the inlet diffuser, but the porous media model could not accurately simulate the flow distribution across the perforated plates. Overall, this model failed to predict the deflection of incoming flow on the solid bars and the wakes behind the bars, and could not reflect the vena contracta phenomenon occurring within the holes of the plate. As a result, the simulated flow distribution at the entrance of the main dust-collection chamber differed from that observed in the experiment, which resulted in poor prediction of the flow field inside the chamber. Therefore, this porous media model requires further improvement for wide-scale adoption in industrial practical applications, e.g., ESP for flue gas treatment in power plants. • Examination of the porous media model for simulating flow through perforated plates. • Experimental validation provided by particle image velocimetry (PIV) measurements. • Results compared with simulations fully resolving the perforations in the plates. • Porous media model cannot capture detailed flow physics such as the vena contracta. • The model inaccurately overestimates the streamwise directionality of the flow. [ABSTRACT FROM AUTHOR]

This work modeling the collection efficiency of an ESP numerical model based on industrial plant development. Under high dust loads, one power supply controlled the voltages on the two separation zones. The separation efficiency is different depending on the diameter of the dust particles, so the two zones receive dust particles with various distributions, and the electrical characteristics are not the same. In this article, we show the change in the efficiency of separation when the two zones are controlled at different voltages by power supplies. [ABSTRACT FROM AUTHOR]

This paper presents the study of a novel semi-circular corrugated wire-plate electrostatic precipitator (ESP) for capturing submicron particles emitted from the burning of biomass residue. The discharge of residual gases from biomass combustion is widely acknowledged to be hazardous to human health. The main objective of ESP is to control the release of residual gases. The numerical simulation was performed to evaluate the collection efficiency, space charge density, electric field, gas dynamics, and flow behaviour in the ESP with flat and semi-circular corrugated plates. The influence of electrohydrodynamic (EHD) flow and flow velocity on collection efficiency and particle trajectory had also been investigated at different applied voltages with various gas velocities. The results showed that the flow velocity had a significant influence on ESP performance and vortices formed in the flat plate ESP could be suppressed using a semi-circular corrugated plate ESP, which would be beneficial for collecting particles efficiently. The numerical results showed that the collection efficiency of semi-circular corrugated plate ESP compared to flat plate ESP is 33.33% higher for 2 µm and 25% for 5 µm particles. [ABSTRACT FROM AUTHOR]

The electrodes of industrial electrostatic precipitators degrade as a result of two phenomena: corrosion and erosion. The first is chemical degradation by highly reactive compounds formed during combustion, in particular, during the incineration of municipal or industrial wastes or high-sulfur coal. The degradation intensity of electrostatic precipitator electrodes depends on the chemical composition of the exhaust gasses. High concentrations of chlorides, fluorides, or sulfur in the exhaust gasses cause strong corrosion of the electrostatic precipitator elements. The second mechanism is the erosion caused by solid particles conveyed by the exhaust gas stream due to their collision with the electrodes. In this study, the analysis of the degradation of electrodes of an electrostatic precipitator downstream of an industrial waste incinerator was carried out. The industrial wastes of unknown sources were subjected to thermal degradation in a rotary kiln. The aim of this study was to provide fundamental knowledge about the mechanisms of electrode degradation located on the surface of discharge electrodes of electrostatic precipitators during the combustion of industrial wastes.

Introduction/purpose: Hydrogen is the most abundant element in the universe (75 % by mass) and the lightest element (with a density of 0.00082 g/cm3) which consists of only one proton and one electron. Because of its presence in many different forms such as gaseous hydrogen, its plasma species, water, acid, alkalline, ammmonia and hydrocarbons, it has various applications in different industrial disciplines. Methods: Different hydrometallurgical and pyrometallurgical methods are considered in order to point out many different processes such as formation of hydrogen, reduction of metallic oxides and chlorides, and electrochemical reactions such as hydrogen overvoltage and the spillover effect. Ultrasonic spray pyrolysis enables the formation of very fine aerosols which can be used for the production of metallic powders. Results: Hydrogen formation was observed during the dissolution of metallic allloys with hydrochloric acid. The reduction of metallic oxides and metallic chlorides by hydrogen leads to the formation of metallic powders. Metallic powders were collected by a new developed electrostatic precipitator. Conclusion: Hydrogen can be applied in different reduction processes for the production of metallic powders. Recycling processes can be used for the formation of hydrogen. A new research strategy for powder production is proposed combining recycling of the black mass of used Li-Ion batteries, ultrasonic spray pyrolysis, and hydrogen reduction.

Fires in nuclear fuel fabrication and reprocessing plants can cause the rupture of the glove box (GB) containment with a risk of dispersion of plutonium dioxide (PuO2) within the facility. Fire safety analyses need to assess the resulting radiological consequences to strengthen the appropriate prevention and protection measures in these plants. To this end, the French Institute for Radiation Protection and Nuclear Safety (IRSN), in partnership with the Japanese Nuclear Regulation Authority (NRA), has carried out since 2019 a research project that aims at assessing the airborne release fraction (ARF) of PuO2 involved in GB fires. This project, named FIGARO (Fires Involving Glove boxes with Aerosol Release Occurrences) follows a progressive approach, that has started with small and medium-scale analytical tests to study separately the various mechanisms involved in the GB fires and the PuO2 airborne release and will end with large-scale GB fire tests to transpose and validate the analytical works for realistic assessments of the ARF of PuO2 both in open and confined conditions. This project also includes the development of a GB fire model in the IRSN SYLVIA and CALIF3S-ISIS softwares and its validation. In addition to presenting the FIGARO program, this paper provides its first outcomes.

To solve the dust pollution problem, this paper proposes a new grounded electrode atomized corona discharge coupled with a screen dust collection pole dust collector (ASEP). The discharge characteristics of the wire-barrel electrode (with an aperture of 0 mm) and the wire-mesh barrel electrode (with screen apertures of 1, 2, and 3 mm, respectively) were compared, and the factors influencing the dust removal efficiency were investigated. In the case of grounded atomized negative corona discharge, the discharge characteristics of the wire-barrel electrode (aperture of 0 mm) and wire-mesh barrel electrode (screen aperture of 1 mm) were compared, and the influencing factors of the dust removal efficiency were studied. In the case of grounded electrode atomization negative corona discharge, it is found that the wire-mesh cylinder electrode (screen aperture of 1 mm) has the best dust removal efficiency, and the total charge of the grounded electrode atomization corona discharge of the wire-mesh cylinder structure is dominated by air ionization charge, and the charged liquid droplets only play the role of cleaning.

To achieve the optimum dust removal performance of an electrostatic precipitator, the flue gas should be distributed uniformly over its vertical cross-section. The flow in the upstream flue gas ducts has a significant influence on the downstream gas distribution in the chamber of the precipitator. This paper presents the results of homogeneity assessment of velocity distribution in the ducts and vertical cross-sections of the electrostatic precipitator of Unit A1 at the Nikola Tesla thermal power plant in Obrenovac. The measurements confirmed that the reconstruction of the vertical chamber at the front of the precipitator, which was carried out during the overhaul in 2020, effectively solved the problem of the original asymmetric arrangement of the vertical flue gas ducts. Nevertheless, the analysis revealed poor homogeneity of the flow field through the chambers. Therefore, additional measures must be taken to increase the dust removal efficiency of the precipitator. [ABSTRACT FROM AUTHOR]

The removal of fine particles from coal-fired power plants and the zero-discharge treatment of desulfurization wastewater (DW) from wet desulfurization are critical issues. In this study, we propose a charged droplet evaporation technology of DW for efficient electrostatic dust removal, aiming to achieve zero discharge of DW and effectively remove fine particles. We experimentally studied the effect of charged DW droplet evaporation on the dust removal efficiency of an electrostatic precipitator (ESP) and analyzed the internal mechanism. The results revealed that the removal efficiency of fine particles by ESP was affected by electrode voltage, atomization pressure, DW volume flow, and Cl− concentration. The main internal mechanisms that improved the removal efficiency of fine particles were agglomeration and pre-charging of the particles. Increasing the electrode voltage proved to be the most effective method in enhancing the removal efficiency of fine particles. Specifically, when the electrode voltage was increased from 0 to 12 kV, the removal efficiency of PM 2.5 by ESP demonstrated an increase of greater 14 %. The removal efficiency in the penetrating window exhibited an increase of greater than 8 %. Furthermore, augmenting the atomization pressure and DW volume flow also contributed to the improvement in fine particle removal by ESP. In contrast, increasing the Cl− concentration had a detrimental effect on the removal process. [ABSTRACT FROM AUTHOR]

A cost-effective power supply design proposed for electrostatic precipitators (ESP) is presented in this work. The cost minimization is done in terms of eliminating the power transformer and reducing power consumed by the ESP unit. Usually, transformers are used to boost the voltage level in conventional systems on its input side, which is replaced by a combination of a high-frequency converter along with a voltage multiplier in a modular arrangement. By interconnecting these modules, the suitable voltage is built-up easily. An intermittent pulse energized supply is developed by the proposed system to reduce back corona and to save energy consumption. The modular arrangement also increases the lifetime of converter switches, by reducing the switching stresses developed across them during its high-frequency operation and by reducing the Total Harmonic Distortion (THD). The complete system is designed and analyzed using MATLAB SIMULINK. The obtained results are better than the existing methods used for generating intermittent energization, the THD is reduced to 35.78% and the voltage stresses also reduced to 1800 V. And a module is experimented and found that it is capable of producing 3 kV. [ABSTRACT FROM AUTHOR]

This study numerically investigated the ultrafine particle collection characteristics in the two-stage electrostatic precipitator with the dielectric plate according to the shape of the dielectric separator and air inlet velocity. This study developed a multi-physics model which analyzes the electrostatic characteristics and particle motion of the electrostatic precipitator and was implemented by using UDF (user defined function) in Ansys Fluent. The effect of the electro-hydrodynamic flow induced by the corona discharge formed in the vicinity of the high voltage wire on the air flow in the charged region of the electrostatic precipitator was investigated. The trajectories of charged ultrafine particles and their collection efficiency depended on the shape of the dielectric separator and air inlet velocity. The collection efficiency for the wavy dielectric separator is higher when the air inlet velocity is low and lower when the air inlet velocity is high, compared to that for the flat dielectric precipitator. [ABSTRACT FROM AUTHOR]

Small industries are inseparable from the production of gaseous pollutants. One of the contents of exhaust gases produced from small industrial activities is particulate matter. The consequences of exposure to particulate matter for too long are coughing, cancer, blood coagulation, and death. For this reason, a tool is needed to capture particulate matter in small industrial exhaust gases. Based on the problems described, this research proposes using the electrostatic precipitator with the cockroft-walton method because this method is very effective in capturing particulate matter. The research results on electrostatic precipitator (ESP) with a pair of electrodes will achieve an efficiency of 25.4% when the voltage regulator is 20 V, while the efficiency is 98.7% when the voltage regulator is 35 V. The ESP with two pairs of electrodes will achieve 99.5% efficiency when the voltage regulator is 30 volts. Installing a vibrator as a particle thresher at the electrode is unsuitable for low-temperature exhaust gases because it produces a liquid and sticky residue that makes it difficult to fall off. [ABSTRACT FROM AUTHOR]

In this paper, a multi-physics field coupled model of electric, flow and particle fields was constructed by COMSOL to compare the effects of three different corrugated dust collector plates on electric field distribution, airflow field, particle trajectories and dust removal efficiency in an electrostatic precipitator, and to compare them with a conventional electrostatic precipitator with a parallel plate structure. The results indicated that the corrugated dust collection plate influenced the electric field within the ESP channel, while the wire plate spacing directly affected the size and distribution of space charge density. Furthermore, the corrugated dust collection plate also affected the EHD flow within the channel, with the D2-ESP and D3-ESP being the most strongly influenced by the ionic wind. By comparing the dust removal efficiency of the four ESPs, we found that D2-ESP has the highest dust removal efficiency, followed by D3-ESP, then Flat-ESP, and finally D1-ESP. The ranking order of the four ESPs' dust removal efficiency is consistent with the ranking order of the space charge density within the four ESP channels, which shows that the size of the space charge density directly affects the dust removal efficiency of ESPs. Numerical simulation results show that the change of wire plate spacing is the main reason why corrugated ESP affects the dust removal efficiency of electrostatic precipitators. [Display omitted] [ABSTRACT FROM AUTHOR]

An analysis of industrial operation of EGAV 1-19-15-6-2 electrostatic precipitators designed for purifying non-aggressive non-explosive process gases and aspiration air from dust was carried out. The nonuniformity of flow distribution at the inlet to the working volume of electrostatic precipitators was revealed. This non-uniformity can lead to efficiency deterioration, increased energy consumption, and frequent cleaning of precipitation electrodes. The authors proposed constructive improvements of electrostatic precipitators supported with calculations. [ABSTRACT FROM AUTHOR]

For particles produced in the governance industry, expounds and summarizes the mechanical dust removal，bag dust removal, wet dust removal, electrostatic dust removal process characteristics, this paper introduces the typical technology research background and application value of electrostatic dust removal technology process principle and research progress, summarizes the factors aftecting electrostatic technology discharge characteristics, highlights the discharge electrode material and dust specific resistance on dust removal efficiency, points out the possible problems of electrostatic precipitator. [ABSTRACT FROM AUTHOR]

At the Coal Power Plant the Electrostatic Precipitator (ESP) functions as a catcher of fine dust that is in the exhaust ducts from coal combustion. It is known that the ash attached to the electrode which has an electric charge is difficult to drop using a vibrator, by using the Power Off Rapping (POR) method, which is to temporarily turn off the electric charge on the electrode; the ash attached to the electrode plate will be more easy to miss. This research is a quantitative research that aims to determine the effect of the ESP operating method on energy consumption, determine the energy consumption ratio of each current setting, determine the dust capture efficiency ratio of each current setting and find energy saving opportunities using the following data analysis techniques. The energy consumption calculation used is only the energy consumption of the rectifier transformer on the electrostatic precipitator excluding hopper heaters, box heaters and rappers. After getting the test results from the current setting simulation, it can be concluded that the current setting of 20% is the most optimal setting in accordance with Ministry of Environment and Forestry Regulation No. 15 of 2019 the threshold limit for particulate exhaust gases at coal fired power plants is 100 mg/Nm3 where the dust reading value is 80.15 mg/m3. By using a current setting of 20%, a savings of 38.97% can be made for the operating method without POR and 41.88% for the POR operating method. If the difference in energy consumption is converted to rupiah by using the electricity tariff for large industrial groups (I-4/TT) of IDR 996.74/kWh, then the savings in electricity costs in 1 month of operation are IDR 176,802,877 without the POR method and IDR 189,988,881 with the POR method. [ABSTRACT FROM AUTHOR]

Introduction/purpose: Hydrogen is the most abundant element in the universe (75 % by mass) and the lightest element (with a density of 0.00082 g/cm3) which consists of only one proton and one electron. Because of its presence in many different forms such as gaseous hydrogen, its plasma species, water, acid, alkalline, ammmonia and hydrocarbons, it has various applications in different industrial disciplines. Methods: Different hydrometallurgical and pyrometallurgical methods are considered in order to point out many different processes such as formation of hydrogen, reduction of metallic oxides and chlorides, and electrochemical reactions such as hydrogen overvoltage and the spillover effect. Ultrasonic spray pyrolysis enables the formation of very fine aerosols which can be used for the production of metallic powders. Results: Hydrogen formation was observed during the dissolution of metallic allloys with hydrochloric acid. The reduction of metallic oxides and metallic chlorides by hydrogen leads to the formation of metallic powders. Metallic powders were collected by a new developed electrostatic precipitator. Conclusion: Hydrogen can be applied in different reduction processes for the production of metallic powders. Recycling processes can be used for the formation of hydrogen. A new research strategy for powder production is proposed combining recycling of the black mass of used Li-Ion batteries, ultrasonic spray pyrolysis, and hydrogen reduction. [ABSTRACT FROM AUTHOR]

An electrostatic precipitator is an essential piece of equipment to eliminate atmospheric dust pollution. Its power supply is of great significance to the working efficiency and reliability of the dust collector. This paper uses field-programmable gate array (FPGA) technology to design an electrostatic precipitator power controller. In this paper, a fuzzy control scheme with variable scale factors is adopted to make the highest average voltage between the two poles of the precipitator better approach the critical breakdown voltage. In this paper, the transfer function is derived based on the finite element differential equation and the method of three-dimensional drawing. In this way, the influence of parameters such as the coupling inductance of the pulse power supply, the coupling coefficient, and the parasitic resistance of the dust removal chamber on the load oscillation can be obtained. It is found that the control system can control the electrostatic precipitator power well. It can significantly improve dust removal efficiency.

The assessment of airborne viruses in air is a critical step in the design of appropriate prevention and control measures. Hence, herein, we developed a novel wet-type electrostatic air sampler using a viral dissolution buffer containing a radical scavenging agent, and verified the concentration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in the air of hospital rooms inhabiting coronavirus disease 2019 (COVID-19) patients and public areas. RNA damage caused by corona discharge was negligible when Buffer AVL was used as the collecting electrode. The viral RNA concentration in the air of the room varied by patient: 3.9 × 103 copy/m3 on the 10th day after onset in a mild case and 1.3 × 103 copy/m3 on the 18th day in a severe case. Viral RNA levels were 7.8 × 102 and 1.9 × 102 copy/m3 in the air of the office and food court, respectively, where people removed their masks when eating and talking, but it remained undetected in the station corridor where all the people were wearing masks. The assessment of airborne SARS-CoV-2 RNA using the proposed sampler can serve as a basis for the safe discontinuation of COVID-19 isolation precautions to identify exposure hotspots and alert individuals at increased infection risks. [ABSTRACT FROM AUTHOR]

This paper investigates the removal efficiency of a honeycomb electrostatic precipitator (ESP) applied to control particulate matter (PM) emissions from a small-scale boiler with combustion lignite and hard coal. The specifics of the precipitation of emissions from small-scale boilers are discussed, and the design principles for relevant ESPs are presented and used. The ion-induced nucleation of sulfuric acid occurred, causing the drastic penetration of 19 nm particles through the ESP. Despite this, the overall collection efficiency was sufficient to meet the EU's Ecodesign Directive requirements. Back corona was not detected. The optimal ESP performance is defined with further parameters: a current density of 0.5 mA/m2 at an electric field strength of about 2.7 × 105 V/m; a minimal specific collecting area of ESP (SCA) of 60 m2/(m3/s); and Nt-product of 4.5 × 1014 s/m3. Such parameters of ESPs should ensure adequate PM emissions control for any type of boiler with similar emissions characteristics. The composition of collected fly ash particles was analysed, and a method for fly ash utilisation was proposed. This research may be helpful for designing ESPs to control PM emissions for small-scale units with fossil fuel combustion. [ABSTRACT FROM AUTHOR]

Environmental pollution caused by human activities, the harmful mixture of gases (CO, CO2, NO2, SO2, PM), resulting from industrial production processes and vehicular traffic is a global environmental health problem in urban and rural areas; it affects vulnerable groups, children and older adults, affecting respiratory, cardiovascular and cancerous diseases. In Ecuador, in the city of Cuenca, among the main sources of contamination is the vehicle fleet in high-traffic areas and avenues; in addition to the industrial zone, that coexists with the city within the urban area in the northwest zone, which generates contamination to properties located around these strips. This paper presents the development of a purifying element based on the "evolutionary development" model. It begins by analyzing and studying concepts of lattices, ionization, and air purification, among others; subsequently, existing air purification systems are investigated in detail and a prototype of an ionizing lattice is generated, whose function is to filter polluted air when installed as an aesthetic part in buildings. Finally, the purification performance of gases and particles typical of the electrostatic precipitator (ESP) was tested by means of air quality stations. By means of a type of correlational applied research, the similarity between external and internal gases and particulate matter was verified, obtaining, as a result, the effective reduction of the same; decreasing by 4.15% of CO2, 30% of CO and 57% of particulate matter. With this analysis, it is concluded that the prototype of the ionization air purifying lattice can be efficient with some of the gases against particulate pollution in domestic interiors, positively influencing the health of the inhabitants of a building. [ABSTRACT FROM AUTHOR]

Electrostatic precipitators (ESP) have gotten a lot of attention lately because of their great efficiency and low cost. Designing ESP for applications in the industry, numerical simulation is generally used as it is a powerful, cost-effective, as well as an adaptable tool. The numerical models of ESP that are available simulate different physical processes, such as electric field ionization, movement of air, charging of particles and their motion, are summarized in this paper. We know that existing models could produce results within acceptable range, and computing power needed for applications in industry are not very large.

Ionic wind is a phenomenon of electrofluid movement in electrostatic precipitator, which changes the motion state of flue gas and dust in electrostatic precipitator to a certain extent. In order to study the influence of ionic wind on air flow characteristics in electrostatic precipitator, this paper constructed a numerical model of electric field-flow field coupling and compared the impact of electro-hydro dynamics (EHD) effect on flue gas flow state at different inlet velocities. In addition, this paper analyzed the influence of EHD effect on the motion trajectories of particles with different sizes. The results showed that the EHD effect changed the flue gas flow field near the anode plate at 0.3m/s inlet velocity, forming an obvious reflux region; this phenomenon weakened when the inlet velocity increased. At the same time, the EHD effect reduced the dust removal efficiency when the particle radius ranged from 0.25 µm to 1 µm. [ABSTRACT FROM AUTHOR]

Emissions of marine traffic can be lowered by switching to less polluting fuels or by investing in exhaust aftertreatment. Electrostatic precipitation is a widely used method for particle removal but it is not currently used in combination with marine engines. This study presents the particle filtration characteristics of an emission reduction system designed for marine applications and consisting of a scrubber and a Wet Electrostatic Precipitator (WESP) in series. Partial flow of exhaust from a 1.6 MW marine engine, operated with light and heavy fuel oil, was led to the system. Particle concentrations were measured before the system, after the scrubber and after the WESP. Particle removal characteristics were determined for different engine loads. The scrubber alone removed 15–55% of non-volatile particle number, 30–40% of particle mass and 30–40% of black carbon mass depending on engine load, when HFO fuel was used. By studying particle size distributions, scrubber was found also to generate particles seen as an additional mode in 20–40 nm size range. The system combining the scrubber and WESP removed over 98.5% of particles in number, mass and black carbon metrics when HFO fuel was used. With MDO fuel, 96.5% of PN and 99% of black carbon were removed. [ABSTRACT FROM AUTHOR]

On the way to reducing emissions released into the atmosphere, there is an obstacle in the form of the emissions of solid pollutants produced by households, namely the burning of solid fuels in small heat sources. In this article, the authors deal with the development of a low-cost electrostatic precipitator, which would be able to significantly reduce the production of particulate matter. This is a tubular precipitator concept, which is enhanced by dividing the precipitation space into four chambers, each of which has an ionization electrode. With the investigated structural arrangement, it is possible to increase the size of the collection area without affecting the external dimensions of the separator. The essence of this article was to focus on the design of an ionization electrode, which, in addition to the function of a negative electrode, would also fulfill the function of a structural element of the proposed geometry. The work contains a technical design for the shape of the ionization electrode, which was subsequently examined using ANSYS Fluent software. The conditions under which a corona discharge will occur on the electrodes and how particulate matter is captured in the separation device were investigated with the help of simulations of the electric field intensity. According to the achieved simulation results, calculations were made for the theoretical efficiency of particle collection, which reached a value of approximately 78%. [ABSTRACT FROM AUTHOR]