Precipitator Research Articles

Review on Enhancement of Electrostatic Precipitator in Automobiles

The Electrostatic Precipitator (ESP) is a widely employed device in boilers to mitigate the release of particulate matter. This study proposes the design and fabrication of a similar device tailored for reducing emissions from automobiles, particularly targeting older versions of BS vehicles lacking dedicated emission control mechanisms. Despite the catalytic converters equipped in BS-6 vehicles, there exists a need for an efficient emission reduction solution for their predecessors. This research aims to analyse various ESP designs through Computational Fluid Dynamics (CFD) simulations using ANSYS software. The design optimization will be conducted based on fluid flow analysis, leading to the fabrication of the most optimal prototype. The final step involves testing the fabricated prototype to ensure compliance with Pollution Under Control (PUC) standards, contributing to environmental sustainability.

Soil organic carbon enrichment in the particulate matter emitted by rural soils: A laboratory assessment

AbstractThe aim of this study was to assess the organic carbon (OC) content in the PM10 emitted by agricultural soils and rural roads under controlled conditions. Samples were collected from agricultural soils and rural roads. The PM10 was generated and collected using an electrostatic precipitator coupled with the Easy Dust Generator (EDG). This procedure ensures that the PM10 collected come specifically from soil. OC contents were measured in both the soil and PM10. The enrichment ratio (ER) was calculated as the ratio between OC content in the PM10 and OC content in the soil. The results showed that OC content in the PM10 ranged from 2.7% to 3.5% in agricultural soils and from 1.4% to 2.9% in rural roads. These values were comparable with the OC contents observed in fine particles transported by the wind, but lower than OC contents observed in PM10 samples collected in rural areas using active samplers and filters. A quadratic function described the association between OC in PM10 and OC in the soil. A negative potential function described the association between ERs and OC in the soil. Both associations suggested a saturation of OC in PM10 when the OC content in the soil was high. This information is crucial for a better comprehending of the dust emission role in the redistribution of OC within terrestrial ecosystems and to the atmosphere and oceans.

The comprehensive impact and mechanism of carbon finance on carbon emission: Evidence from 30 countries and regions

The present invention discloses a cathode frame of an electrostatic precipitator, comprising a rectangular frame composed of four horizontal bars and five vertical bars; The horizontal and vertical bars are perpendicular to each other and located in the same plane, and four horizontal bars are arranged parallel to each other, while five vertical bars are arranged parallel to each other; Four horizontal bars divide the longitudinal length of the rectangular box into three equal parts, five vertical bars divide the transverse length of the rectangular box into 2:1:1:2, and one of the vertical bars is located on the vertical centerline of the rectangular box; The upper section of the two outermost vertical rods on the rectangular frame is a reinforced vertical rod, and there are two horizontal through-holes on the reinforced vertical rod for installing the cathode frame support. The cathode frame of the electrostatic precipitator has a simple structure and convenient assembly, which can effectively prevent the cathode frame of the electrostatic precipitator from bending, deformation, or even sliding and collapsing from the overall cathode support, greatly improving the safety and stability of the operation of the electrostatic precipitator.

DESIGN OF RICE HUSK ROTARY DRYER USING WASTE HEAT ELECTROSTATIC PRECIPITATOR OF THE CEMENT INDUSTRY

ESP or electrostatic precipitator is a device used to capture particulate matter, such as dust, in exhaust gases using electrostatic principles. In the cement industry, ESP is commonly placed after the clinker cooler to clean the exhaust air from the cooling process, ensuring it is free from clinker dust. The clinker cooler is a device that cools down the clinker using air, reducing its temperature from an initial temperature of around 1450°C to approximately 100°C - 120°C. The exhaust air from the clinker cooler is then passed through the ESP at temperatures ranging from around 237°C to 311°C. Based on the temperature data, the exhaust air from the ESP has the potential for heat reuse for other processes, including as a heat source for drying rice husk, which is a common alternative fuel used in the cement industry and typically has a moisture content of around 25%-37%. The results of this design indicate that the exhaust heat from the ESP, with an input temperature of 275°C, is capable of drying rice straw pellets from a moisture content of 25% to 14.73% using a designed rotary dryer with a capacity of 21.6 t/h, a length of 41.58 m, and a diameter of 2.92 m. It is constructed using ASTM 283 C material with a thickness of 8.76 mm and is insulated with a 15.6 mm thick layer of aluminum foil.

PM2.5 Collection Efficiency of Wire-Plate Electrostatic Precipitator: Prediction of Temperature Effects Using Support Vector Machine Model Combined with Particle Swarm Optimization Algorithm

PM_2.5 Collection Efficiency of Wire-Plate Electrostatic Precipitator: Prediction of Temperature Effects Using Support Vector Machine Model Combined with Particle Swarm Optimization Algorithm

A NUMERICAL ANALYSIS ON THE SUBMICRON- AND MICRON-SIZED PARTICLE SEDIMENTATION IN A WIRE-TO-PLATE ELECTROSTATIC PRECIPITATOR

Electrostatic precipitators (ESPs) are frequently utilized in collecting fine organic and inorganic materials from continuous liquid with few moving parts and high efficiency using electrically charging the particles. In this study, cross-sectional 2D geometry of a wire-to-plate electrostatic precipitator the parametric data of which originally published elsewhere was numerically modeled and validated to investigate submicron-micron particle charging in terms of diffusion and field charging mechanisms and precipitation behavior of particles with detailed electric field properties. Electric field, gas flow, and particle trajectory equations are coupled and solved in a multiphysics solver. Particle tracking is realized with the Lagrangian approach. Results indicate variations in electric field strength and space charge density between corona electrodes, with space charge present in the entire precipitation channel. Between two different charging mechanisms, diffusion charging prevails for charge accumulated on submicron particles, whereas field charging becomes dominant for particles larger than 1μm diameter. However, for the ESP configuration considered in this study, particles reach a charge saturation in less than 0.7 seconds, regardless of their size. Although calculated precipitation efficiencies for micron-sized particles can reach to 100%, efficiencies for submicron particle range drop with increasing particle size, as diffusion charging rapidly loses its effectiveness, in 50-250nm range.

Numerical Study of the Influence of Using Semicircular Corrugated Collecting Plate and Inverted Semicircular Corrugated on the Electrostatic Precipitator

Electrostatic precipitators (ESPs) play a crucial role in removing harmful particles in various industries. Ongoing studies continuously strive to improve their performance and efficiency, leveraging the inherent advantages of ESPs. Researchers are exploring various types of collecting and discharge electrodes to achieve this. This study specifically focuses on comparing two types of collecting electrodes, Semicircular Corrugated Plates (SCPs) and inverted Semicircular Corrugated Plates (InvSCPs), against Flat Plates (FPs) as a reference case. Three distinct forms of ESPs were simulated, and the SCP and InvSCP designs were evaluated against the FPs, specifically assessing the impact of modifying the collecting electrode design on key electrostatic precipitator characteristics, such as electrical field distribution, space charge density distribution, particle trajectories, and particle collection efficiency. Notably, the study found that using SCP resulted in the highest particle collection efficiency compared to InvSCP and FP for the same range of particles.

The Behavior and Removal of Condensable Particulate Matter in Flue Gas in a Multi-Field Force: A Modeling and Experimental Study

Condensable particulate matter (CPM) is different from filterable particulate matter (FPM), which could escape from air pollution control devices (APCDs) and pose a great threat to the environment and human health. Thus, modeling and experimental studies were conducted on CPM particle behavior and removal, in a cold electrode electrostatic precipitator (CE−ESP) coupled with a electric field, temperature field and concentration field. A multi−field force coupling model was then established that was based on the mechanical behavior of particles inside the CE−ESP. The results showed that temperature field was beneficial to depositing small size particles and that, the greater the temperature gradient, the higher CPM’s removal efficiency. While the electric field tended to gather larger size particles, the greater the voltage provided, the higher the removal efficiency for CPM and FPM. In the multi−field, the augmented coagulation and the removal efficiencies of both CPM and FPM increased significantly, reaching 89% and 98%, respectively. Subsequently, experiments were conducted by a self−made CE−ESP device, which showed the removal efficiencies of CE−ESP of a CPM in a multi−field were 91% and 81% for a coal−fired power plant and a waste incineration plant, respectively. This research could make a great contribution to CPM condensation, aggregation and removal.

Cd(II) and Pb(II) adsorption in karst soils amended with litter extract from Ficus virens

In this study, different proportions of Le were used to amend purple, yellow, and yellow–brown soils of karst areas to investigate the effect of litter extract (Le) from Ficus virens on Cd(II) and Pb(II) adsorption in karst soils. The basic physicochemical properties of Le-amended karst soils were determined, and the microscopic morphology of Le-amended karst soils was detected. The batch method was used to study the isothermal adsorption characteristics of Cd(II) and Pb(II) adsorption on different Le-amended karst soils. Physicochemical properties and microscopic morphology results showed that Le was amended on the karst soil surface and changed the surface properties of the karst soil. The maximum adsorption capacity range of Cd(II) and Pb(II) by Le-amended karst soils was 92.10–241.61 and 108.91–262.12 mmol/kg, respectively, and the peak value was reached when the karst soils were amended with 20 % of Le. Increasing the pH and temperature were beneficial to Cd(II) and Pb(II) adsorption in each Le-amended karst soil. The adsorption amount of Cd(II) and Pb(II) initially increased and thendecreased with the increase in ionic strength. Cd(II) and Pb(II) adsorption was a spontaneous, endothermic, and entropy-increasing process, and electrostatic attraction, precipitation, complexation, and ion exchange were the main adsorption mechanisms. The adsorption amount of Cd(II) and Pb(II) by Le-amended yellow–brown soil maintained approximately 85 % of original sample after three rounds of regeneration.

Hybrid electrostatic filtration systems for exhaust gas cleaning

Emission of submicron and nanoparticles by industrial processes, like coal or biomass combustion, solid waste incineration, cement kiln heating, and glass production is a serious environmental problem. The application of most effective bag filters is limited due to very high temperature of the exhaust gases from most of these processes, sometimes >1000 K, which the filter material cannot resists. Cyclones, which could be resistant to these temperatures, are not effective for PM2.5 particles removal, which are the most abundant in these processes. Electrostatic precipitators remove dust from flue gases with high mass collection efficiency, but in submicron range (~100 nm to 1 μm) the so called “penetration window” occurs, in which the fractional collection efficiency decreases even below 50% at minimum. Hybrid electrostatic filtration systems, which combines various conventional gas-cleaning devices were therefore proposed and tested in several research papers, in order to improve the overall collection efficiency of the precipitation processes. The heart in all of these devices is an electrostatic particle charger, which can be a conventional electrostatic precipitator, a corona-discharge particle precharger, or electrostatic particle agglomerator. After charging and/or agglomeration, the particles can be further removed by other devices like cyclones, electrostatic precipitators, or bag filters (after gas cooling to an allowable temperature). The paper reviews specific problems encountered in exhaust gas cleaning from various industrial processes, and the most interesting constructions designed for this goal. In particular, an example of a system comprising a unipolar electrostatic agglomerator, which simultaneously charges the particles and agglomerates them in alternating electric field, for the formation of aggregates of finer particles (PM1) with larger species, which could be removed by any conventional gas cleaning device, with sufficiently high collection efficiency, has been discussed in details.

Particle removal performance of a novel ESP type air cleaning system for indoor air quality in a subway station

A novel electrostatic precipitation type air cleaning technology with near zero ozone emission for indoor air quality of a subway station was developed. To minimize ozone emission and achieve high particle removal performance against ultrafine particulate matters (PMs), a multi-channel charging method using soft ionization by micrometre carbon fibers and a narrow gap collection method using high electric field by thin conductive plastic sheets as a high voltage electrode were used. In this study, the novel electrostatic charging and collection technologies were applied to a real scale air cleaning system in an Air Handling Unit (AHU) with air flow rate of 950 m3/min in Yuseong Oncheon subway station with an area of 3000 m2 in Daejeon, South Korea. The particle removal performance of the demonstration system was evaluated with real suspended particles in the subway station during test period with high PM concentrations in Korea over 40 μg/m3. Particle collection efficiency, pressure drop and ozone emission were evaluated, and compared to those of the a minimum efficiency reporting value (MERV) 10 and 14 filters used in the typical subway stations in Korea. In the field researches, the developed ESP achieved over 80% of the PM collection efficiency higher than those of the filters with MERV-10 and -14, and even 10% higher efficiency against PM1.0, while generating only 10% of pressure drop and also emitting nearly zero ozone. It is concluded that a novel ESP type air cleaning system with near zero ozone emission could be a promising air cleaning method for a large indoor environment such as a subway station where polluted air with ultrafine particles flowed in with a very high flow rate.

Investigation on Condensation Characteristics and Removal Performance of SO3 in Low-Low-Temperature Electrostatic Precipitator

The low-low-temperature electrostatic precipitator (LLT-ESP) is considered one of the mainstream technological approaches for achieving ultra-low ash emissions and has already been applied in many coal-fired power plants. Particulate matter and SO3 can both be removed by LLT-ESP. However, the removal performance of SO3 is relatively lower than that of particulate matter, which is caused by the condensation characteristics of SO3. In this paper, the condensation characteristics of SO3 were investigated on a simulated experimental system, and several measurement and characteristic methods were used to investigate mechanisms. After reducing the flue gas temperature with a heat exchanger, the size distribution of particulate matter, the mass concentration of SO3 on different sizes of particulate matter, as well as the microscopic morphology and elemental composition of particulate matter, were all experimentally studied. The results indicate that gaseous SO3 transformed into a liquid phase by heterogeneous or homogeneous condensation and then adhered to the surface of particulate matter through nucleation–condensation, collision–coalescence, and adsorption reactions. Furthermore, the removal efficiency of SO3 in LLT-ESP was also investigated under various conditions, such as ash concentration and flue gas temperature drop, suggesting that a higher ash concentration and a more significant temperature drop were beneficial for improving SO3 removal efficiency. Nevertheless, it is worth noting that the impact was limited by a further increase in ash concentration and a drop in flue gas temperature.

Multimedia Mercury Recovery from Coal-Fired Power Plants Utilizing N-Containing Conjugated Polymer Functionalized Fly Ash.

To recover multimedia mercury from coal-fired power plants, a novel N-containing conjugated polymer (polyaniline and polypyrrole) functionalized fly ash was prepared, which could continuously adsorb 99.2% of gaseous Hg0 at a high space velocity of 368,500 h-1 and nearly 100% of aqueous Hg2+ in the solution pH range of 2-12. The adsorption capacities of Hg0 and Hg2+ reach 1.62 and 101.36 mg/g, respectively. Such a kind of adsorbent has good environmental applicability, i.e. good resistance to coexisting O2/NO/SO2 and coexisting Na+/K+/Ca2+/Mg2+/SO42-. This adsorbent has very low specific resistances (6 × 106-5 × 109 Ω·cm) and thus can be easily collected by an electrostatic precipitator under low-voltage (0.1-0.8 kV). The Hg-saturated adsorbent can desorb almost 100% Hg under relatively low temperature (<250 °C). Characterization and theoretical calculations reveal that conjugated-N is the critical site for adsorbing both Hg0 and Hg2+ as well as activating chlorine. Gaseous Hg0 is oxidized and adsorbed in the form of HgXClX(ad), while aqueous Hg2+ is adsorbed to form a complex with conjugated-N, and parts of Hg2+ are reduced to Hg+ by conjugated-N. This adsorbent can be easily large-scale manufactured; thus, this novel solid waste functionalization method is promising to be applied in coal-fired power plants and other Hg-involving industrial scenes.

Research on the Method of Calculating Short-circuit Voltage for High-voltage Rectifier Transformer for Electrostatic Precipitation by Using the ANSYS Maxwell

Research on the Method of Calculating Short-circuit Voltage for High-voltage Rectifier Transformer for Electrostatic Precipitation by Using the ANSYS Maxwell

Enhancement of PM2.5 removal efficiency in high-temperature ESP under multi-field coupling: A numerical simulation study on temperature and magnetic field effects

To investigate the working mechanism of electrostatic precipitator (ESP) in industrial scenarios and improve its PM2.5 capture performance, a multi-field coupling model of high-temperature ESP is developed based on the introduction of magnetic field. The influence mechanism of temperature field on flow field, particle dynamics field and electromagnetic field is analyzed, and PM2.5 dust-removal efficiency at different working voltages is numerically simulated. The results show that the dust-removal efficiency in the environment with or without magnetic field increases with the equal amplitude of working voltage, but the increased magnitude decreases, and it constantly drops with the increase of temperature, and the dropped trend continually weakens. Magnetic field can effectively enhance PM2.5 dust-removal efficiency, and its enhanced degree ascends when the temperature rises and the working voltage declines. The results of this work are useful for technological innovation in industrial fields related to electrostatic precipitation.

Recovery of ammonia nitrogen and phosphate from livestock farm wastewater by iron-magnesium oxide coupled lignite and its potential for resource utilization.

A new adsorbent called iron-magnesium oxide coupled lignite (CIMBC) was developed to address the challenges of recovering high concentrations of ammonia nitrogen and phosphate in livestock farm wastewater and improving the inefficient use of lignite (BC) with low calorific value. CIMBC was synthesized using the modified ferromagnesium salt double-coating method. The experiments demonstrated that Fe2O3 and MgO could be effectively loaded onto the surface of BC at a Fe/Mg molar ratio of 1:2 and pyrolysis temperature of 500°C. The optimal conditions for adsorption were determined to be an N/P concentration ratio of 2:1, adsorbent dosage of 1g/L, and pH of 7. The presence of coexisting cations (Ca2+ and Mg2+) inhibited the removal of ammonia nitrogen but enhanced the removal of phosphate. Likewise, the presence of coexisting anions (CO32- and SO42-) hindered the removal of both ammonia nitrogen and phosphate. The adsorption behavior followed the pseudo-second-order model and the Langmuir model, with a maximum adsorption capacity of 95.69mg N/g for ammonia nitrogen and 101.32mg P/g for phosphate. The adsorption process was a spontaneous endothermic process controlled by multiple levels. The main mechanisms of adsorption involved electrostatic attraction, intra-particle diffusion, ion exchange, chemical precipitation, and coordination exchange. After 5 times of adsorption-desorption, the recovery rate of CIMBC is less than 50%, and the removal rate of phosphate is less than 40%. Although the RCIMBC exhibited low reusability, but also it showed potential in removing heavy metals (Pb) from wastewater and for use as a slow-release fertilizer. CIMBC is a promising new adsorbent, which can realize resource utilization of lignite with low calorific value while removing nitrogen and phosphorus.

Emission characteristics and removal of heavy metals in flue gas: a case study in waste incineration and coal-fired power plants.

Heavy metal pollutants such as Hg, As, Pb, Cr, and Cd emitted from coal and waste combustion have received widespread attention. In this study, we systematically investigated the emission characteristics of heavy metals in waste incineration and coal-fired flue gases, focused on testing the removal effect of self-made cold electrode electrostatic precipitator (CE-ESP) on heavy metals in flue gas, and made a comparative analysis with the existing air pollution control devices (APCDs). Test results from waste incineration power plant showed that each APCD showed a certain effect on the removal of heavy metals in condensable particulate matter (CPM), with an average removal efficiency of bag filter was 86%, but its effect on Hg removal was slightly worse. Under the coupled field with electrified cold electrode plate operation mode, the average removal efficiency of CE-ESP on heavy metals in CPM was as high as 93%, including 76% for Hg. The removal efficiency of heavy metals (especially Hg) in CPM increased with the increase of flue gas temperature difference between inlet and outlet of CE-ESP. Test results from this coal-fired power plant showed that heavy metals were enriched in fly ash to a higher degree than in slag, the synergistic control of heavy metals in submicron particulate matter by the dust remover was not obvious, and there was a significant correlation between each heavy metal emission factor and its content in coal. Under the temperature field with non-electric cold electrode plate operation mode, the overall effect of CE-ESP on the removal of gaseous heavy metals was better than that of particulate heavy metals. Under the conventional electric field operation mode, CE-ESP was less effective in removing particulate Cr and gaseous Hg0. Under the coupled field with electrified cold electrode plate operation mode, the average removal efficiencies of CE-ESP for particulate and gaseous heavy metals were 82.37% and 76.16%, respectively.

ПРЕДПОСЫЛКИ К РАЗРАБОТКЕ СИСТЕМ ОБЕЗЗАРАЖИВАНИЯ ВОЗДУХА СВИНОВОДЧЕСКИХ ПОМЕЩЕНИЙ С ПОМОЩЬЮ ЭЛЕКТРОФИЛЬТРОВ

Studies of microclimate parameters have shown the influence of microbial contamination on the productivity, growth and development of young pigs. It is known from the literature that exceeding the level of microbial contamination by 5 percent led to a decrease in the growth of piglets at weaning by 13.3 percent, in fattening pigs - to a decrease in live weight at slaughter by 3.7 percent. In addition, infectious diseases caused by pathogenic microorganisms affect the productivity of animals. For example, pneumogastroenteritis, transmitted aerogenically, affects from 30 to 95 percent of suckling piglets and weaning piglets. The damage caused by animal disease takes form of loss in productivity, death of sick animals and forced slaughter, as well as treatment costs. One of the promising and effective ways to clean the ventilation air in pig-breeding premises is the use of electrofiltration, including a wet electrofilter. There is little information in the scientific literature on the issues of disinfection of the air environment of pig-breeding premises from microbial contamination using electrofilters, which necessitates a more thorough consideration of this issue. (Research purpose) The research purpose is substantiating the prerequisites for the development of a methodology for determining the effectiveness of air disinfection with wet electrostatic filtering. (Materials and methods). The available studies on supply and exhaust ventilation systems and methods for determining the effectiveness of air purification by electrofilters from microorganisms were reviewed. Cited their shortcomings. (Results and discussion). It was found that wet electrostatic precipitators in the process of air purification generate ozone into the air, which is capable of destroying up to 95-99 percent of the population of dangerous microorganisms. It has been shown that by modernizing the air purification system in terms of improving the mechanisms for controlling ozone generation with a wet electrostatic precipitator, it is possible to improve the quality of the air environment by disinfecting the air with ozone. (Conclusions) It was determined that the effectiveness of cleaning the air of pig-breeding premises from microorganisms using wet electrostatic precipitators is relevant, further theoretical and experimental studies are needed.

Design and Characterization of a Melt Electrostatic Precipitator for Advanced Drug Formulations

Electrostatic precipitators (ESP) are especially known for the efficient separation of micron and submicron particles from aerosols. Wet electrostatic precipitators are particularly suitable for highly resistive materials. Using these, particles can be directly transferred into a liquid for further processing or safer handling, which is advantageous for either hazardous or valuable materials. In this work, a wet ESP, which enables the separation of highly resistive particles into a heated liquid, was designed and investigated. To do this, spray-dried drug particles were embedded in a molten sugar alcohol to enhance the drug dissolution rate. After cooling, the solidified product showed advantageous properties such as a high drug dissolution rate and easy handling for further processing. For the design of the wet ESP, different discharge electrode configurations were tested. A wall film served as the collection electrode, which was generated by a specially designed distributer die. A laminar flow regime was achieved with a homogeneous film serving as the collection electrode, which is particularly important for a high separation efficiency. A prototype was designed and constructed in this respect. The particle separation into hot liquids or onto hot surfaces is challenging due to thermal effects in ESPs. The influence of thermophoresis and drag force on the particle transport was investigated, and optimum operation parameters were found for the present ESP. A broad field of applications can be covered with the presented device, where particles are embedded in even hot liquids to form liquid suspensions or, as it is presented here, solid dispersions. The dissolution of the drug-containing solid dispersion was studied in vitro. A remarkably faster drug dissolution was observed from the solid dispersion, as compared to a powder mixture of the drug and xylitol.

Electrostatic precipitator upgrade for stricter emission regulation

Electrostatic precipitator (ESP) is still one of the best dust collecting equipment used in many industries. However, in this modern world, many countries, through their government authorities, make the emission rule stricter in order to achieve healthier and cleaner environment. Original design of the ESP may not comply with the stricter rule resulting in complaints from the neighborhood and fines from the government. Through research and development, the original equipment manufacturer (OEM) of ESP is finding a way to upgrade the ESP without building a new one. Replacing the mechanical parts of the ESP is one of the ways, especially changing the design to a better one, such as rigid discharge electrode (RDE). The performance of the upstream fields will be improved thus bring better performance to the following fields as well. The other way is by replacing the electrical part which is the transformer/rectifier (T/R) set. With the recent technology and development, the new T/R set, which is a switch mode power supply (SMPS) become more sensitive responding to spark or arc and working on high frequency (25000Hz) resulting on better power output of the field and better performance to the whole ESP. This paper will further discuss several case studies which adapt the upgrade options with almost has 50% emission reduction.