Industrial Dust Collector Inquiry
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Industrial Dust Collector Inquiry

Industrial Dust Collector Inquiry

How To Design Dust Extraction System for Multi Dust Emission Points-Tablet Coating Pans As Example?

How To Design Dust Extraction System for Multi Dust Emission Points-Tablet Coating Pans As Example   The production workshop of a pharmaceutical factory has a construction area of about 3240m². It is a single-story building with partial 2 floors. The building height is about 10m. The indoor ceiling height is 2.7m. The upper part is the equipment pipeline layer, and the partial 2-story building is the air-conditioning machine room. Area H is the sugar coating packaging workshop with a total of 12 sugar coating machines.During the pharmaceutical production process in the sugar-coating workshop of a pharmaceutical factory, a large amount of process talc dust will escape, and effective dust removal measures need to be taken. If dust removal measures are not handled properly, the dust will pollute the indoor air, block and contaminate the purification air-conditioning system, affect the physical and mental health of the staff, thereby destroying the requirements for a clean production environment in the production room and the quality of pharmaceuticals;And it causes pollution to the outdoor atmospheric environment. Energy Saving Consideration Since the dust generation points of process dust are concentrated near the process equipment in the clean room, in order to save energy (such as purifying air conditioning system energy: power supply, exhaust, cooling, heat load, etc.) and saving production space, the layout of the production process is generally considered. , the area of the dust-producing production area should be minimized. Therefore, the room ventilation air volume per unit time is smaller (relativelyFor the dust removal system, the available exhaust air volume is also small, and it is necessary to reasonably select the air volume, wind speed, dust collection device and dust removal equipment). Local ventilation is is better than whole room ventilation External suction hood. When the production equipment cannot be sealed due to limitations of process conditions, the exhaust hood can be placed near the source of harmful substances. The suction effect of the hood can be used to create a certain air flow at the point where the pollution source emanates, and the harmful substances can be removed. Suction into hood. In this design, the pollution source produces light mineral talc dust, which disperses into the above-mentioned calm air at a slight speed. Therefore, the control speed of the pollution source can be obtained from the control air speed table of the control point in "Industrial Ventilation", which is 0.5m/s~1.0 m/s. This design uses v=0.6m/s. Determination of exhaust volume and size of suction hood 1): Top Design The exhaust hood is located above the sugar coating machine. Due to equipment limitations, gas can only flow into the hood from the side, as shown in Figure 3.2. In order to avoid cross-air flow interference, it is required that H should be ≤0.3L as much as possible (the long side dimension of the cover mouth), take H=0.4m, therefore, L≥1.33m, take L=1.4m. 2): Suction hood size:The diameter of the umbrella-shaped suction cover is: 0.56+2×0.4H=0.56+2×0.4×0.4=0.88(m)The perimeter of the suction hood is: 3.14×0.88=2.76(m)3) In order to ensure the uniform inhalation speed of the mask mouth, a is set to 60° in this design.4) The exhaust air volume is calculated according to the following formula:Q=KPHvx=1.4×2.76×0.4×0.6=0.93(m²/s)=3348(m³/h)In the formula: P --- perimeter of the open surface of the hood, m; H---- distance from the mask mouth to the pollution source, m;vx-----Control speed, m/s;K----Considering the uneven velocity distribution along the height, the safety factor is usually taken as K=1.4. Pipe design First, design the layout position of the pipeline, then number each pipe section, and select the calculation loop according to the principle of maximum pressure loss. Determination of the minimum speed in the pipeline In this design, the pollutant is light mineral powder. According to the "Ventilation and Dust Removal Equipment Design Manual", the minimum flow velocity in the horizontal pipe is 14m/s and the vertical pipe is 12m/s.                               Minimum air flow velocity in dust removal ventilation duct (m/s) Dust propertiesVertical pipeHorizontal PipeDust propertiesVertical pipeHorizontal Pipem/sm/sPowdered clay and sand1113Iron and steel (chips)1923Fire clay1417dust1618heavy mineral dust1416sawdust, chippings1214light mineral dust1214Large dry sawdust1415dry sand1113dry dust810 coal ash 10 12fuel dust 14-16 16-18 Wet soil (less than 2% moisture) 15 18Large pieces of wet sawdust 18 20 Iron and steel (dust) 13 15grain dust 10 12 cotton 8 10Hemp, short fiber dust 8 12 Pipe material Choosing  In the dust removal system of a pharmaceutical factory's clean room, materials such as pipes and fittings and valves should be selected based on the physical and chemical properties of the materials being transported and the working conditions. The materials and valves used should meet the process requirements and should not adsorb or pollute the media. The exposed pipelines introduced into the medical clean room (area) should be made of stainless steel or other materials that do not pollute the environment. Air ducts in pharmaceutical factories are usually made of SUS materials (high-quality galvanized steel plates can also be used). The material thickness is determined according to the corrosiveness and abrasion of the dust. For smaller dust removal systems, a plate thickness of 1.2mm to 2mm is generally sufficient. This design uses thin steel plate because its advantages are that it is easy to be processed and manufactured industrially, easy to install, and can withstand higher temperatures. Selection of air duct cross-section shape The cross-sectional shapes of air ducts are round and rectangular. Compared with the two, when the cross-sectional area is the same, the circular air duct has less resistance, saves material, and has greater strength; when the diameter of the circular air duct is smaller, it is easier to manufacture and is more convenient for thermal insulation. However, it is more difficult to lay out and make circular air duct fittings than rectangular air ducts; it is not easy to coordinate with the building and structure when laying out, and it is not easy to arrange beautifully when exposed. When the flow velocity in the air duct is high and the diameter of the air duct is small, a circular air duct is usually used, so a round air duct is selected here.The flow rate in the air duct should be determined from both technical and economic aspects. Judging from the actual engineering situation, it is appropriate to choose a lower flow rate (selectable lower limit of flow rate) for the dust removal system in the pharmaceutical factory's clean room, and should be combined with reasonable air duct layout, which can save energy consumption. With appropriate technology, it will not Cause dust precipitation and blockage. After the flow rate and flow rate of the air duct are determined, the cross-sectional size of the duct can be calculated as follows:Q=(π d²V)/4 gets:d=√4Q/πVd—Duct diameter mQ—Dust gas flow rate m³/sV—dust gas flow velocity m/s Determination of elbow When laying out pipes, try to keep straight lines and reduce elbows. The radius of curvature of circular air duct elbows should generally be greater than (1~2) times the pipe diameter. Therefore, a 90° elbow is taken here. Due to the erosion and wear of the elbow by the dusty airflow in the pipeline, it is easy to wear through and leak air, which affects the normal dust collection effect. Therefore, wear-resistant facilities must be installed on the elbow. Determination of three links The collision between two airflows with different flow speeds in the tee and the formation of vortices when the airflow speed changes causes local resistance. In order to reduce the local resistance of the tee, the ejector phenomenon should be avoided, and attention should be paid to the connection between the branch pipe and the main pipe to reduce the angle. Therefore, the angle between the branch pipe and the main pipe is a=30; at the same time, the branch pipe should also be as close as possible to the main pipe. Maintain the same flow rate as the flow rate in the main pipe. Like elbows, tee fittings should also be equipped with wear-resistant facilities.Using 30° converging tee: resistance coefficient ξ=0.20 force coefficient ξ=0.18. Then use a "Pipe pressure calculator" App to calculate the pressure loss. If you do not have, please ask ACMAN for help: Dust Collector Choosing When selecting a dust collector, the properties and particle size distribution of the dust, the temperature and properties of the gas, and the dust concentration of the gas should be considered.Factors such as the degree of dust removal and the problem of handling dust removed by the dust collector.The properties of dust have a great influence on the performance of the dust collector. For example, dust with greater viscosity is easy to adhere to the surface of the dust collector and is not suitable for dry dust removal; dust with too large or too small specific resistance is not suitable for electrostatic dust removal. When dealing with abrasive dust, the bag dust collector should use wear-resistant filter media. Different dust collectors have completely different dust removal efficiencies for dust with different particle sizes.Similarly, when choosing a dust collector, you must first understand the particle size distribution of the dust to be processed and the classification efficiency of various dust collectors.During the sugar-coating packaging process in the sugar-coating workshop, talc dust will be emitted, affecting the personal health of employees and the air quality in the workshop. In severe cases, the accumulation of a large amount of dust may cause an explosion and affect production. Therefore, the dusty air needs to be purified after being collected. Allowed to vent to atmosphere. Since the collected talc dust has a small particle size between 0.5 and 1.0 μm, and it also contains certain medicinal ingredients, it needs to be recycled. The cartridge dust collector has an efficiency of up to 1.0 μm for dust.98%~99%. Therefore, the choice of cartridge dust collector has a small footprint and high cost performance. Blower Choosing Select the appropriate fan and motor based on the air volume and total resistance of the system.1) Determine the type of fan based on the properties of the transported gas, the air volume and resistance of the system.This fan transports talc dust. Due to the fluidity of the dust, static electricity will be generated and cause an explosion. Therefore, an explosion-proof fan is selected.2) Taking into account the air leakage and resistance calculation of air ducts and equipment, the air volume and air pressure should be selected according to the following formula:machine:Pf=KpΔP          (Pa)  In the formula, Pf——the wind pressure of the fan;Kp additional coefficient of wind pressure, general air supply and exhaust system Kp=1.1~1.15; dust removal system Kp=1.15~1.20;ΔP——the total resistance of the coefficient;LF=KLL (m³/h)In the formula,LF—the air volume of the fan;KL——Additional coefficient of air volume, general air supply and exhaust system K₁=1.1; dust removal system K₁=1.1~1.15L——The total air volume of the coefficient.Fan wind pressure  Pf=KpΔP=1.15×1609.3=1850.7Pa Fan air volume   LF=KLL=1.15×42336=48686.4m³h select 4-68No.10 fan, its performance is Pf=2030 Pa    LF=49040 m3/hFan speed: n=2300r/min.Equipped with YZ25S-4 motor, the power of the motor is N=40KW. Conclusion At last, You can Find the suitable dust collector in ACMAN product list:https://www.acman-dustcollector.com/products-list.htm

How to Design Dust Collection and Ventilation System for Pharmaceutical Cleanroom?

How to Design Dust Collection and Ventilation System for Pharmaceutical Cleanroom? Dust pollution is a pollution problem that many production companies such as chemical industry, medicine, light industry, etc. may encounter.Dust pollution caused by pharmaceutical companies in the production of solid preparations not only has the characteristics and hazards of general dust, but also contains the toxic hazards of medicine. Mixing of medicine or cross-contamination will occur through the purification air-conditioning system, which will also affect human health and the environment. It is also relatively large and must be effectively captured and controlled before it can be discharged after effective treatment. In particular, with the implementation of the revised Environmental Protection Law, the requirements for the treatment and emission of air pollutants have become more stringent. In environmental management, dust emissions at the boundaries of pharmaceutical factories should usually meet the comprehensive emission standards for air pollution and the concentration limits for unorganized emission monitoring, that is, ≤1.0 mg/m3.According to the particularity of pharmaceutical production, how can its dust emissions meet the "Good Manufacturing Practice for Pharmaceuticals" (referred to as GMP) and "Pharmaceutical Industry Clean Factory Design Specifications" while achieving effective control of pollutants and environmentally friendly emissions to ensure that pharmaceuticals Improving production quality, preventing the occurrence of contamination and cross-contamination, and protecting the health of company employees are important issues that must be solved during the design and production process of pharmaceutical clean plants, and are also a vital task for engineering designers.This article combines the actual production, starting from the dust generation link in pharmaceutical production, and discusses how to choose a reasonable, effective and easy-to-operate dust removal system in the dust operation room of pharmaceutical clean plants. 1: Which process points generate dust? In the production of solid preparations, the processes that generate large amounts of dust and are most prone to dust flying and spreading are: weighing, crushing, sieving, granulating, drying, granulating, mixing, tableting, coating, filling and other processes.Although in the design and selection of equipment for these processes, in order to effectively prevent the generation of dust during the production process, production equipment that meets the requirements of "GMP" has been selected, and unit equipment should work under negative pressure or in a closed environment as much as possible, and some even Dust-producing equipment is also equipped with dust suction devices and other measures, but it is still unavoidable that a large amount of dust will be generated during the feeding, unloading and equipment cleaning of each process. If effective collection, control and cleaning are not carried out, Clear, there will be mixing or cross-contamination problems through the purification air conditioning system 2: Dust removal and ventilation principles in the operating rooms According to GMP Article 53: Dust-producing operation rooms (such as sampling, weighing, mixing, packaging, etc. of dry materials or products) should maintain a relative negative pressure or take special measures to prevent the spread of dust and avoid cross-contamination. , and easy to clean.Generally, the measures taken for dust-generating operation rooms are as follows: First, install external dust hoods in local locations, especially for equipment that generates large amounts of dust, to achieve local dust exhaust; Second, when local dust exhaust cannot be achieved for dust sources, , the dust source equipment is isolated with enclosure facilities within a wide range, and different air purification schemes are designed according to the air cleanliness requirements of the process; third, the pressure difference between inside and outside the workshop is used to suppress the flow of airflow and prevent the spread of dust. , avoid cross-contamination and facilitate cleaning; fourth, adopt new ventilation and full exhaust measures for the production of solid preparation workshops with high drug sensitivity and drug activity. 3: Dust removal and ventilation design in operation room After taking the above measures, the dust-laden air in the dust-producing operation room needs to be purified by dust removal equipment, and can only be discharged to the outdoors after meeting the standards. Therefore, exploring the dust removal and ventilation technology and equipment is a prerequisite for achieving dust removal and ventilation in dust-producing operation rooms to comply with relevant GMP regulations and meet environmental protection emission requirements.3.1 Selection of dust removal equipmentWhen selecting dust removal equipment, in addition to considering the equipment structure and its dust removal efficiency, it should also be based on the properties of the dust (bulk density, hydrophilicity, adhesion, specific resistance and particle size) and the properties of the gas (temperature, humidity, chemical properties, etc.) and indoor and outdoor operating conditions and other comprehensive considerations.Dust collectors can usually be divided into two types: dry dust collectors and wet dust collectors. There are two types of dry dust collectors: filter type (cartridge dust collector, bag dust collector, etc.) and mechanical type (inertial dust collector, settling chamber, cyclone dust collector, etc.).According to practical experience, filter-type dry dust collectors are mainly used as dust collectors in solid preparation workshops of pharmaceutical factories. Commonly used ones include the following:1) Cartridge dust collector.Using the method of combining gravity and filter material, large particle size powder from dusty air enters the box. Under the action of its own weight, it is separated from the dusty air and settles into the dust drawer. The remaining dust particles are filtered by the filter element. Collision, hooking, static electricity and other effects are retained on the outer wall of the filter element to achieve purification purposes. At the same time, it is also equipped with an automatic pulse backflush self-cleaning device.The cartridge dust collector has the advantages of stable technical performance, low noise, low power consumption, beautiful appearance, flexible use, small footprint, wide application range, and high dust removal efficiency (99.99%).2) Bag dust collector.It is a dry high-efficiency dust collector that separates and captures dust in dust-containing gas through filter materials. It is not suitable to purify dusty gas containing oil mist, condensation water and high dust cohesion, as well as smoke with explosion hazard or sparks. For example: dust removal in coating room.3) Primary, medium and high-efficiency fan boxes.The basic components consist of a fan, air filter, air volume regulating valve and box. Has the following characteristics:①Capture 1~5μm particle dust and various suspended matter;② Using hot melt process, the structure is stable and the risk of leakage is reduced;③Large air volume;④Small resistance;⑤High dust holding capacity;⑥Can be cleaned and used repeatedly;⑦Efficiency: 60%~95%.Disadvantages: When the amount of dust is large, the fan box needs to be cleaned manually, which greatly increases the labor of employees. 3.2 Dust collector settingsThere are two basic forms of dust collector settings. One is stand-alone dust removal. That is, one piece of equipment is equipped with a dust collector, and its exhaust air can be circulated indoors, such as a separate dust collector for a tablet press.The other is centralized dust removal. That is, multiple dust-producing equipment share one dust collector, such as the crusher and oscillating screen in the powder screen room share one dust collector. The air suction, discharge and installation in the dust-producing operation room are all in the dust removal machine room in the non-purification area. After being processed by the dust collector, it is discharged from the workshop through the exhaust port.3.3 Selection of dust removal process systemChoosing an appropriate dust removal process system needs to be determined based on the specific production process. The general principles are: ① Set up a system when the production process is the same, the work is synchronized, the dust points are not far apart, and different dust types are allowed to be mixed and recycled or have no recycling value;② If the dust-containing gases have different temperatures and humidity and condensation will occur in the air duct after mixing, separate systems should be installed.3.4 Reasonable process layoutUnder the condition that the workshop layout meets the relevant conditions of process production, specifications and regulations, people and logistics should be separated and not crossed as much as possible, the process route should be smooth, the logistics route should be short and quick, and there should be no backflow or detours. Reduce the flying and spreading of dust from the source and reduce mutual influence. Centrally arrange process areas with large amounts of dust and noise to facilitate dust treatment. Project cases Design of the solid preparation workshop of a pharmaceutical factory in Kunming.First of all, based on the above principles and combined with the production process, we rationally layout and organize the air flow and air volume distribution. Centrally arrange the weighing and batching room, mixing room and tablet pressing room to avoid cross-contamination and facilitate cleaning; the design considers only one dust removal system and sharing a dust removal machine room; adopt local fresh air exhaust measures, and clean the air according to the process According to the requirements of the degree, the dust removal standards in other areas of the workshop are maintained by designing a purification air conditioning scheme. In accordance with the requirements of environmental management, the emission standards of the dust removal machine room meet the requirements of the unorganized emission monitoring concentration limit of "GB16297-1996 Comprehensive Air Pollution Emission Standard".The detailed layout of the ventilation and dust removal in the solid preparation workshop of this pharmaceutical factory is shown in Figure 1.Secondly, two different ventilation and dust removal methods were compared and selected for the dust removal process system, and finally the second method was adopted as the design solution.Method 1: Local dust exhaust plus environmental dust removal method, see Figure 2 for details. Figure 2 Partial dust exhaust plus environmental dust removal method A dust collection hood is installed above the equipment in the dust production room for local dust exhaust. The suction hood and the inside of the dust hood are in a negative pressure state. The dust-containing gas is transported to the dust removal machine room through the negative pressure of the pipeline, and is dusted by the cartridge dust collector. After reaching the standard, it is directly discharged to the outdoor atmosphere through the chimney.If some dust still exists in the dust-producing room environment after partial dust removal, air supply from above the dust-producing room and side exhaust are used to transport the dust-containing gas in the dust-producing room environment to the dust removal machine room through negative pressure pipes. After dust removal treatment in the medium-efficiency fan box, it will be directly discharged to the atmospheric environment through the chimney after reaching the standard.Above the equipment in the dust-producing operation room, a dust collection hood is installed for local dust exhaust. The suction hood and the inside of the dust hood are in a negative pressure state, and the dust-containing gas is transported to the dust removal machine room through the negative pressure of the pipeline, and is dusted by the cartridge dust collector. After reaching the standard, it is directly discharged to the outdoor atmosphere through the chimney.If some dust still exists in the dust-producing room environment after partial dust removal, air supply from above the dust-producing room and side exhaust are used to transport the dust-containing gas in the dust-producing room environment to the dust removal machine room through negative pressure pipes. After dust removal treatment in the medium-efficiency fan box, it will be directly discharged to the atmospheric environment through the chimney after reaching the standard. Method 2: Only environmental dust removal method is provided, see Figure 3 for details. Figure 3 Only environmental dust removal methodDust removal is only carried out for the space environment in the dust-producing operation room, and no local dust exhaust is performed. That is: increase the air supply and exhaust volume, and still use air supply from above the dust-generating operation room. The side exhaust method transports the dust-laden gas in the dust-producing operation room to the dust removal machine room through negative pressure pipes, where it is removed by the cartridge dust collector and then directly discharged to the outdoor atmospheric environment through the chimney.The choice of method two in this case is mainly determined based on the production process and the amount of dust generated by the specific process. Compared with method one, method two has the characteristics of short process, easy adjustment of air pressure and air volume in the clean area of the workshop, and simple process operation. At the same time, the cartridge dust collector is equipped with an automatic pulse backflush dust cleaning device, which has high dust removal efficiency. The equipment is also arranged to operate in a non-clean area, which can save labor costs and reduce energy consumption.The design scheme has been proven in practice that the dust removal effect is very obvious, which not only meets the requirements of the new version of GMP, but also meets the requirements of the unorganized emission monitoring concentration limit of the comprehensive emission standard of air pollution. Conclusion The production dust in the dust operation room of a pharmaceutical clean factory has its own uniqueness. The two dust removal process systems in this case are often used in the design, each with its own advantages and disadvantages. The key is to fully understand the properties of dust and gas at each dust generation point and the operating conditions, flexibly choose economical and applicable dust removal measures, and design the best dust removal plan.

How to Clean the Sinter Plate Filter? Herding Delta 2 Plastic PE+PTFE Filter Element

How to Clean the Sinter Plate Filter? -Herding Delta 2 Plastic PE+PTFE Filter Element Sinter plate filter elements feature a PTFE-coating that is embedded into the matrix of the rigid body. This leads to a consequent surface filtration and an effective protection against damage and / or penetrations into the filter media.That means the sinter plate filter do not need manually cleaning?In some occasions, the sinter plate need to washing and cleaning, here we give the ways to clean the plastic porous sinter plate filter. Structure of the Filter How to Washing the Sinter-plate Filters 1. Take out the sintered plate in the dust collector and place it on the tray horizontally, as shown in the figure.Lay horizontally, stacked end to end, with padding (cardboard strips) between each other.If there is no suitable place to place it, it is recommended to take out one piece and clean one piece. 2. Take a sintered plate and place it vertically, use a soft brush to remove the dust on the surface of the sintered plate.Rinse the filter element from top to bottom with clean water at room temperature, so that the dust on the surface of the sintered plate is washed away with the water flow.3. Under normal circumstances, the above steps can clean the sintered plate.4. If there is residual dust on the surface of the sintered plate, it may be caused by dust crusting. The whole sintered plate needs to be immersed in water to loosen the dust on the filter plate。5. The soaked sintered plate needs to be washed and then rinsed twice.6. Dry or air dry the sintered plate. The drying time is at least 8 hours, and the temperature of the drying room is about 50~60 degrees; the drying time requires at least 16 hours of sunshine time.After the above is completed, the sintered plate can be used again

What is Electrostatic electret air filter?

What is Electrostatic electret air filter  Electrostatic electret air filter for dust collector Electrostatic electret air filter material, which uses the electrostatic force of electric charge to trap dust particles, and is made of small strips of polypropylene film.Electrostatic electret air filter material: referred to as electret, refers to those dielectric materials that can store space charge and dipole charge for a long time, that is, in terms of time span, their charge decay time constant is longer than the period formed by electret. many. The electret charge can be a real charge (or space charge), a dipole charge, or both. Electret air filter material uses the electrostatic force of electric charge to capture dust particles. Material In recent years, the development of polymer chemical fiber production technology has enabled the production of HEPA and ULPA filters with electret fibers; materials used as electret air filters require excellent dielectric properties, such as high bulk resistance and surface resistance , high dielectric breakdown strength, low hygroscopicity and air permeability, etc. Such materials are mainly organic electret materials based on polymers, such as non-polar materials: polypropylene, PTFE, hexafluoroethylene/polytetrafluoroethylene copolymer, etc.; polar materials or weak polar materials Material: Teflon, polypropylene (blended) and polyester, etc. Synthetic fiber filter material Electret electrostatic synthetic fiber filter material is to electrostatically charge polypropylene fibers in the melt-blown manufacturing process to make them electrostatic electret melt-blown non-woven fabrics (filter paper), with a fiber diameter of 2-5 μm. This filter material not only utilizes the filtering mechanism of traditional air filter materials, but also utilizes the Coulomb force of charged fibers to capture particles, so the efficiency is increased and the resistance is decreased. At present, this filter material is used in the 3M surgical masks (N95, N97, N99) that have the function of preventing viruses (including SARS virus) in the world, and the anti-SARS air filter launched in the United States in April 2003 also uses this filter material Material.Because this filter material has high efficiency, low resistance and low price, this material is used in air filters for general air conditioning and ventilation. When the wind speed on the windward side is 0.5m/s, the dust filtration efficiency of 0.5μm is obtained. It can reach more than 95%, and the air resistance is only 40Pa, which is incomparable to the traditional cabinet air conditioner unit air filter (usually nylon mesh). This air filter has been used in large shopping malls, supermarkets, and hospital air conditioning systems for nearly 10 years, and has been applied to homes, such as Fairway air purifiers, which have achieved good air purification effects.The production process has been comprehensively improved. At present, it has been able to produce electret electrostatic filter materials with a sodium flame method efficiency of 99.9999%. At the same time, it also solves the shortcomings of poor uniformity and low strength of this filter material. Air filters provide an ideal filter material. The commercialization of electret electrostatic synthetic fiber filter material has largely solved the contradiction between air filter efficiency and resistance.

What are the categories of air filter materials?

What are the categories of air filter materials? 1. Chemical fiber non-woven filter material: scientific name polyester fiber, commonly known as non-woven fabric, non-woven fabric has the technical characteristics of wide application, mature technology, good stability, etc. typical filter media. The production process is made of meltblown, acupuncture, spunlace, spunbond and other processes through multiple processes. Compared with other filter materials of the same level, it has stable quality, larger dust holding capacity, strong moisture resistance, long service life, economical and durable Etc.Non-woven fabrics are the earliest filter materials with mature technology and low production costs. Although new filter materials have emerged in an endless stream in recent years, due to high production costs and high technical standards, it is difficult to popularize 2. Synthetic fiber filter material: Synthetic fiber filter material can completely replace non-woven fabrics and glass fiber covering a full range of filter products with coarse, medium and high efficiency (G3-H13) in general filtration environments. It is an emerging filter material. The main development direction of filter materials in the future. Compared with other filter materials of the same level, it has the advantages of low resistance, light weight, large capacity, environmental protection (can be incinerated), and moderate price. Due to the relatively backward domestic processing technology and technical means in the 1990s, the synthetic fiber filter materials at that time were mainly imported.3. Glass fiber filter material: Glass fiber filter material is mainly made of glass fibers of various thicknesses and lengths through special processing technology. Because glass fiber has the characteristics of high temperature resistance, high efficiency, long service life and environmental protection. And in some special circumstances, only the wave line can be competent. Widely used in bag filters and high efficiency filters for general ventilation systems. Glass fiber filter materials and synthetic fiber filter materials are mainly imported, and although the performance is good, there is an actual situation that the price is high.4. Imported cotton fiber: Imported cotton fiber is actually a new type of filter material that is mixed with chemical fiber and cotton fiber. It is mainly used in pre-filtration of coarse efficiency and general air-conditioning systems. Fully imported filter media. It has the characteristics of small resistance, large dust capacity, light weight, stable performance, economical and environmental protection and so on. It is an ideal product to replace non-woven fabrics in future filter equipment.5. Activated carbon filter material: The characteristic of activated carbon is to remove peculiar smell in the air. Activated carbon filter material refers to the activated carbon used in coarse, medium and high-efficiency air filters. There are two main forms of activated carbon filter media - granular and activated carbon filter cotton. Because the function of activated carbon is to remove odors, the filtration efficiency is not emphasized. in use. Generally, it must be used with independent coarse and medium efficiency filters. 6. Long fiber series: chemical fiber, synthetic and glass fiber filter materials all have corresponding long fiber varieties, which are mainly used for filtration of 10μm large particles (such as dust) in special occasions (such as spraying workshop). Large dust holding capacity, high capture rate, can be made into filter pad or flat structure, easy to pave and replace, glass fiber and a small amount of chemical fiber varieties can withstand high temperature.

Current Situation and Development Trend of Air Purification Technology

Current Situation and Development Trend of Air Purification Technology In recent years, due to the development of science and technology and the progress of society, industrial emissions such as factories and automobiles have intensified the deterioration of air quality across the country, and severe weather has occurred frequently. In order to reduce energy consumption and improve the airtightness of the building, the ventilation volume in the building is reduced, and the indoor air environment is further deteriorated. Under this circumstance, people have begun to pay attention to the impact of gradually deteriorating air pollution on their own health and daily life. How to deal with and deal with this problem is a topic that must be studied and explored.At present, the components and sources of indoor pollutants are mainly divided into three categories. The first type of pollutant is particulate matter, especially fine particulate matter led by PM2.5. Because of its extremely small diameter, it can even penetrate deep into human bronchioles and alveoli to deposit, which is extremely harmful to the human respiratory system. The main sources of particulate pollutants are exhaust emissions from automobiles and smoke from incomplete combustion of fuel, as well as kitchen fumes, cigarette smoke and pollutants released from building materials. The second type of pollutants are microorganisms, mainly including bacteria, molds and viruses that are harmful to the human body. Such air pollutants mainly come from damp and moldy walls, domestic garbage, pets, indoor flowers, carpets, and air conditioning filters in the room. Wait. The third type of pollutants are gas pollutants, which are mainly divided into organic pollutants and inorganic pollutants. Organic pollutants include various gas pollutants headed by TVOCs, including alkanes, aldehydes, esters and aromatic hydrocarbons. The main sources are building materials, cleaning agents, wax products, carpets, furniture, adhesives and paints, etc.; inorganic pollutants include carbon monoxide, nitrogen oxides, ammonia, ozone, hydrogen sulfide, radon, etc. The sources include construction, toilets, etc. Sewers, industrial and automotive exhaust, etc. Existing air purification technologies mainly deal with three types of particulate matter, microorganisms and gas pollutants.The author introduces the single air purification technology applied in recent years and the principle of collaborative air purification technology with development potential, and summarizes the purification range, characteristics and development direction of various air purification technologies, and finally looks forward to the future air purification technology.  1 The principle of a single air purification technology 1.1 Fiber Filtration TechnologyFiber filters can be divided into coarse-efficiency filters, medium-efficiency filters, high-efficiency filters, sub-high-efficiency filters and high-efficiency filters according to filtration efficiency. The filter material of the coarse-efficiency filter is mainly wire mesh, coarse-pored cloth, foam plastic, etc. which are easy to clean and replace, and its filtration efficiency is evaluated based on particles with a particle size of 5 μm; The filter materials are mainly medium and fine-pored foam plastics, composite non-woven fabrics, glass fibers, etc., and the filtration efficiency is evaluated based on particles with a particle size of 1 μm; high-efficiency filters are similar to medium-efficiency filters; sub-high-efficiency filters are mainly Glass fiber filter paper, cotton short fiber filter paper, etc. are used, and the filtration efficiency is evaluated based on particles with a particle size of 0.5 μm; high-efficiency filter (HEPA) filter materials are mainly ultra-fine glass fiber paper, synthetic fiber paper and asbestos fiber paper. Filtration efficiency was evaluated based on particles with a particle size of 0.3 μm.The polluted air passes through the fiber filter material, which is mainly affected by the interception effect, inertial collision, diffusion effect, gravity effect and electrostatic effect. The mechanism of action is as follows: the particles move along the streamline to the vicinity of the fiber surface, when the distance from the movement to the fiber surface is equal to or less than the particle radius, the particles will be intercepted by the fiber surface, which is the interception effect (see Figure 1); When the fiber layer passes through, during the violent turning process of the streamline, the particles break away from the streamline due to inertia and collide with the fibers and stay, that is, inertial collision (see Figure 2); for particles with smaller diameters, the Brownian motion is more intense, and this Irregular motion makes the particles have a greater chance of contacting and depositing on the surface of the fiber, that is, diffusion effect (see Figure 3); The electric charge can produce adsorption, and the particles are adsorbed to the fibers, that is, the electrostatic effect. 1.2 Activated carbon and similar materialsAdsorption is caused by the force between the adsorbent and the adsorbate molecules. This adsorption force can generally be divided into two categories: one is the interaction force between molecules caused by van der Waals force; the other is chemical bond force. , including electron transfer between solids and gases. These two forces exist at the same time, depending on which force is dominant. Physical adsorption is dominated by the van der Waals molecular interaction force, and the adsorbate is adsorbed on the surface of the adsorbent, which is a reversible process. Chemisorption relies on the chemical bond force between the solid surface and the adsorbed gas molecules, which is the result of chemical action, and its force far exceeds the van der Waals force of physical adsorption, which is often an irreversible process.At present, the commonly used adsorption materials mainly include activated carbon, activated carbon fiber materials and related derivative materials (such as carbon nanotubes, graphene, etc.):1) Activated carbon is one of the most common adsorption materials, and has a wide range of applications in industrial and daily fields. The raw materials for preparing activated carbon can be mainly divided into plants and minerals: plants include sawdust, coconut shell, walnut shell, etc.; minerals mainly include coal with various degrees of coalification, such as peat, lignite, bituminous coal, anthracite, etc.2) Activated carbon fiber materials have gradually attracted attention due to their better adsorption effect and better physical properties. Different from the structure of activated carbon, activated carbon fibers contain a large number of micropores that open directly on the surface of the fibers. The diffusion path of adsorbate to the adsorption site is shorter than that of activated carbon, and it has a larger surface area (1 000~3 000 m2/g), and the adsorption and desorption is very good. The attachment rate is fast and the adsorption capacity is large. In Figure 4, the left part is the microstructure of activated carbon, and the right side is the microstructure of activated carbon fiber.3) Materials such as carbon nanofibers, carbon nanotubes and graphene are generally not used as the main material of adsorption filter elements in air purification applications due to material costs and other reasons, but are used in some special applications, such as gas sensors, for example A PAN carbon nanofiber/ZnO2/SnO2 composite material can be used as a gas sensor for nerve-like gas DMMP; some foreign scholars have made relevant discussions on the use of carbon nanotubes to prepare gas sensors and detect trace pollution gases; domestic scholars from Tsinghua University The application of such carbonaceous materials in air purification is also described more fully.4) Adsorbents similar to activated carbon materials (such as activated alumina, silica gel and molecular sieves, etc.) are also widely used in industry. For example, gamma alumina is generally used for adsorbents, catalysts and catalyst carriers in petrochemical industries, and macroporous silica gel is generally used for catalyst carriers, matting agents, etc., and the most commonly used adsorbent in the field of air purification is activated carbon. 1.3 Electrostatic PrecipitationThe principle of electrostatic precipitator technology is to use a high-voltage electric field to form a corona, and to pass the polluted air through the corona area, so that the particles in the polluted air are charged, and then under the action of the electric field force, they are adsorbed to the collection area with opposite polarity and deposited. , so as to achieve the effect of purifying particulate matter in the air.The working principle of the commonly used electrostatic precipitator is shown in Figure 5. Generally, the polluted air will pass through a pre-filter to remove large particle pollutants and aerosols, and then pass through the ionization section and the dust collection section to finally obtain purified air. The function of the ionization section is to charge the particles, and the charging process is divided into two stages: corona discharge and charging according to the sequence of the process. In the corona discharge area, because the air molecules will naturally radiate electrons, the electrons are accelerated to a high speed under the action of the electric field force and hit the air molecules, thereby generating positive ions and free electrons. This process is completed instantaneously in the ionization zone, and the free electrons will continue to hit the air molecules, forming a layer of electron cloud or positive ion cloud around the ionization wire.After corona discharge, a large number of positive ions have been generated. The particles and positive ions are mixed together. Due to the Brownian motion of the positive ions, they will hit the particles, and the particles will be positively charged, which is diffusion charging. Diffusion charging does not require an electric field and is independent of the type of particle. As the positive charge on the particle increases, the particle creates an electric field that repels other positive ions, thereby weakening subsequent impacts. When the charge on the particle increases to a certain level, no positive ions can overcome the repulsive force to hit the particle, and the charge ends.The positively charged aerosol particles enter the dust collecting section with the air, are adsorbed by the electric field force, and are adsorbed on the dust collecting plate, thus completing the electrostatic dust removal work. 1.4 Low temperature plasmaLow-temperature plasma is a partially ionized gas that can be generated by applying a high-voltage discharge between two electrodes. It is rich in charged particles, high-energy electrons, and active particles, such as free radicals, excited atoms and molecules. Atoms or molecules in excited states generate various light radiations during electronic transitions. Plasma is generated by high-voltage discharge, and these chemical effects are accompanied by physical effects such as strong electromagnetic fields, thermal effects, and shock waves. Such physical and chemical characteristics can generate huge energy to break chemical bonds and do many complex chemical reactions. Low-temperature plasma shows that it can quickly and efficiently sterilize and deal with complex pollution.There are many methods for generating low temperature plasma, the common ones are electron beam radiation method, low pressure glow discharge method, dielectric barrier discharge method, pulse corona discharge method, DC corona discharge method and so on. The discharge will generate a large number of high-energy electrons and ions to bombard VOCs molecules, and through a series of complex chemical reactions, the pollutant molecules will be decomposed, which can theoretically be finally degraded into harmless products such as CO2 and H2O.1.5 Photocatalytic TechnologyAt present, the commonly used photocatalysts are mainly semiconductor materials represented by TiO2. Taking TiO2 as an example to introduce the principle of photocatalytic air purification technology: when light waves greater than or equal to 3.2 eV (wavelength less than 380 nm) are irradiated on the surface of TiO2, some valence band electrons absorb energy and undergo energy level transitions, and the electrons transition to the conduction band Then, a hole will be generated in the valence band accordingly, thereby forming an electron-hole pair. At this time, the electrons on the conduction band can be used as reducing agents because of their higher energy, and the holes with lower energy can be used as oxidants. When the electron-hole pair has a long enough existence time, it can undergo a redox reaction with the VOCs pollutants adsorbed on the surface of TiO2, so as to achieve the purpose of degrading the pollutants. If nano-TiO2 particles are used, due to the quantum size effect of ultra-fine particles, the photocatalytic activity of the catalyst can be improved. At the same time, the nano-sized particles are small, the surface atoms are many, and the specific surface area is large, and the ability of the photocatalyst to adsorb organic substances is enhanced. The oxidative decomposition of pollutants is more sufficient and effective.The specific reaction of the degradation is described as follows. The holes act as a strong oxidant to oxidize the hydroxyl groups (OH-) and water (H2O) adsorbed on the surface of TiO2 to hydroxyl radicals ( OH), while the conduction band electrons act as a strong reducing agent, which will be absorbed by the TiO2 surface. The dissolved oxygen adsorbed on the surface of TiO2 is captured to form superoxide anion radicals (O-2); some superoxide anion radicals (O-2) can continue to generate hydroxyl radicals (·OH) through chain reaction. The generated superoxide anion free radicals and hydroxyl free radicals have strong oxidizing properties, which can attack the unsaturated bonds of pollutants, or extract hydrogen atoms to generate new free radicals, stimulate chain reactions, oxidize them, and finally cause pollutants. Degrades into harmless substances.1.6 Other purification technologiesThere are also some purification technologies, which have low market application rate and little research value due to large defects or narrow scope of application. For example, the principle of negative ion technology is similar to that of plasma and electrostatic precipitator, but it has the defect of high ozone generation, and it has almost no purification effect on gas pollutants; ultraviolet technology and ozone technology only have good effects on sterilization, and have good effects on particulate matter and gas pollution. Things are powerless; water washing is effective for some gas pollutants that are easily soluble in water, but there are problems such as high air humidity and few types of pollutants.In addition, there is a special kind of purification technology - ozone purification technology. Since technologies such as electrostatic precipitator will produce ozone as a by-product, it is generally necessary to use an ozone purification module when using this type of technology, that is, to eliminate ozone through a catalyst to achieve the effect of purification.2 Introduction of synergistic air purification technologyThe synergistic technology of air purification generally refers to a type of composite technology in which two or more purification technologies combine and promote each other. Different purification technologies can play a synergistic role due to the complementarity of purification mechanisms, and generally have better purification efficiency than the original single technology, so they have strong research value. At present, the more common synergistic technologies include adsorption-photocatalysis technology and low-temperature plasma-photocatalysis technology.2.1 Adsorption-photocatalysis technologyAdsorbent materials such as activated carbon have the advantages of strong adsorption of low-concentration pollutants, but at the same time they have the disadvantage that they can only enrich and cannot degrade pollutants and need to be replaced regularly. However, photocatalytic technology is limited by the problem of reaction contact area and cannot be used for low-concentration pollutants. Contaminants are rapidly degraded. The advantages and disadvantages of the two can be complementary. The adsorption principle is used to enrich the pollutants on the surface of the adsorption material, and then the pollutants are degraded by catalytic technology, which avoids the disadvantage that the adsorption material cannot degrade the pollutants and needs to be replaced regularly. , and avoids the problem that the electrocatalytic technology has a slow rate of treating low-concentration pollutants.In 1997, a Japanese scholar proposed a composite material in which photocatalyst TiO2 was attached to activated carbon particles. After that, some researchers expounded the mechanism of the mutual enhancement of the purification ability of photocatalysts and activated carbon, and prepared different purification materials through different methods and raw materials. For example, a thin layer of TiO2 was formed on the activated carbon carrier by dip coating, and an activated carbon-nano-TiO2 composite photocatalytic air purification net was developed; a Fe-TiO2-zeolite composite material was prepared by a sol-gel method, which was verified by tests. It has high removal efficiency of formaldehyde under visible light; a series of TiO2-molecular sieve/corrugated ceramic fiber composite photocatalyst materials were prepared by dipping and calcination method, and the optimal molecular sieve loading was verified; electrospun nanofiber membrane was used as the Attachment, electrospray technology is used to deposit photocatalyst and activated carbon on the surface of fiber, and further composite multilayer film is obtained by electrospinning technology.2.2 Low temperature plasma-photocatalytic technologyBoth plasma technology and photocatalytic technology are mainly aimed at purifying gaseous pollutants (such as VOCs, etc.) in the air, and the combination of the two can play a role in promoting each other. Experimental studies have compared the purification effects of the two technologies synergistically, low-temperature plasma alone, and photocatalytic technology alone on pollutant formaldehyde.There are many types of low-temperature plasma-photocatalytic coupled reactors currently used for air purification. According to the discharge form, it can be divided into dielectric barrier discharge reactor, creeping discharge reactor, pulse corona discharge reactor, etc. According to the electrode structure, it can be divided into needle plate type, wire plate type, flat plate type, bobbin type, etc. According to the different placement positions of the photocatalyst in the reactor, that is, in the discharge region (in-plasma catalysis, IPC) and the afterglow region (post plasma catalysis, PPC), the reaction system can be divided into two categories. According to this, some researchers refer to them as single-stage plasma catalysis (SPC) and two-stage plasma catalysis (TPC) or plasma-driven catalysis. catalysis, PDC) and plasma-assisted catalysis (plasma-assisted catalysis, PAC. At present, there are many researches on PPC technology. Starting from the principle of low-temperature plasma-photocatalysis technology, it is believed that the catalyst can form a more obvious synergistic effect in the discharge region. A large number of active ions, electrons, free radicals, etc. generated by the plasma generator can, on the one hand, stimulate the particles to transition downward with high energy to generate ultraviolet light, and activate the photocatalyst to produce a catalytic reaction. On the other hand, the plasma discharge has a direct activation effect on the photocatalyst, which can enhance the Its catalytic performance. In addition, the combined action of the two is conducive to the deep reaction of the by-products generated by the reaction, so that they can be completely degraded into harmless products such as H2O and CO2, which effectively improves the degradation efficiency.3 Air purification technology purification range and advantages and disadvantagesEach air purification technology has its applicable purification range, advantages and disadvantages. When applying purification technology, it is necessary to reasonably consider the characteristics of different purification technologies, make full use of strengths and avoid weaknesses, and play its due role. The following is a brief description and summary of the purification range and characteristics of various purification technologies:1) Fiber filtration technology has a good filtering effect on particulate matter. Since microorganisms such as bacteria and viruses are generally attached to suspended particulate matter, it also has a filtering effect on microorganisms, but it has little effect on gas pollutants. Its advantages lie in mature industrial production, safe use, convenient maintenance, and extremely high filtering effect on particulate matter. The disadvantage is that it belongs to non-renewable consumables and needs to be replaced regularly, and it is easy to cause secondary pollution of adsorbed microorganisms in an environment with high humidity. Especially when used in places with serious pollution, its service life is shorter and the maintenance cost is higher. In addition, the high-efficiency filter has a large wind resistance, which requires high static pressure and noise control of the fan.2) Activated carbon adsorption technology has adsorption effect on pollutants, but particulate matter is easy to block the micropores of activated carbon, so that the adsorption force quickly fails, and microorganisms are easy to enrich and reproduce on the adsorption matrix, resulting in secondary pollution, so it is generally used for gas pollutants. purification. Its advantages are that it has a broad spectrum of adsorption capacity, has a certain purification efficiency for almost all gas pollutants, and is the same as the fiber filter, which is safe to use, easy to maintain, and has a large adsorption capacity. It is the most widely used purification material. The disadvantage is that there is a limitation of adsorption capacity, which needs to be replaced regularly, and due to its non-targeted adsorption, it also has adsorption effect on harmless substances in the air (such as water vapor, etc.), which will lead to a decrease in its effective adsorption capacity; no degradation of adsorbed pollutants It is easy to breed microorganisms in a wet environment, causing secondary pollution.3) Electrostatic dust removal technology is mainly used for the purification of various particulate matter, and because the generated charged ions and ozone can effectively destroy the biological structure of bacteria and viruses, it has a good microbial purification effect, but it has almost no effect on gas pollutants. . Its advantages are that compared with high-efficiency fiber filters, the wind resistance is smaller, the filter material is not consumed, the dust collecting board is easy to clean and can be reused, and the sterilization ability is strong, which will not cause secondary pollution. The disadvantage is that the principle of the equipment is complex, there is a high-voltage area, and the maintenance is highly specialized; it is greatly affected by factors such as ambient temperature, humidity and dust specific resistance, and cannot maintain a high purification efficiency; although the generated ozone has a bactericidal effect, it is necessary to prevent In a closed environment, the increased ozone concentration is harmful to human health.4) The application of low-temperature plasma technology in the field of air purification has its unique advantages. The use of high-voltage discharge reaction can degrade VOCs without frequent replacement and low secondary pollution. In addition, the generated high-energy particles, ozone and ultraviolet rays can all play a role in sterilization. However, in actual engineering, there are some problems if the low-temperature plasma technology is used alone. The higher the plasma power, the higher the degradation efficiency of VOCs, but the more toxic by-products. Degradation efficiency will decrease. Low-temperature plasma technology is also less effective for the degradation of inorganic pollutants such as nitrogen oxides. It is also worth mentioning that because the discharge area is filled with a large number of high-energy electrons and ions, as well as by-products such as ozone, it also has a strong killing effect on microorganisms such as bacteria and viruses in the air.5) Photocatalytic technology has development potential in the field of air purification. It reacts at room temperature and pressure, has low energy consumption, and is more energy-saving and safe than low-temperature plasma technology; as a type of catalytic reaction, it can degrade VOCs quickly, effectively and renewable. It does not need to be replaced as frequently as activated carbon; the material has strong plasticity and is easy to use, such as all kinds of tile coatings can be applied. Relevant studies have shown that TiO2 photocatalyst can not only degrade toxic compounds produced by harmful microorganisms, but also directly act on the biological macromolecules of bacteria and viruses to promote their destruction and decomposition to achieve sterilization. However, in the process of research, it was found that the photocatalytic technology represented by TiO2 currently has defects that hinder its industrial application. TiO2 has better catalytic activity mainly at ultraviolet wavelengths and lower efficiency at visible light wavelengths, which may require additional ultraviolet lamps to promote photocatalysis in practical applications. Aromatic VOCs have a low reaction rate under the photocatalysis of TiO2 and can lead to catalyst deactivation. In practical applications, photocatalytic treatment is limited by many factors and the degradation rate is slow. In addition, the incomplete photocatalytic reaction may produce toxic intermediates such as acetaldehyde. For inorganic pollutants such as oxides with relatively stable chemical bonds and radon, the degradation effect of photocatalytic technology is very limited. 4 Development direction of air purification technology1) The fiber filtration technology represented by HEPA is a commonly used particle purification technology, and its market application is very mature. At present, the main development directions are various, mainly reflected in the development of high-fiber nano-molecular materials represented by electrospinning, and the expansion research on this basis. For example, gradient composite filter materials with different densities and pores can filter particles of different diameters in layers to improve filtration efficiency; fuse or coat various catalytic materials, so that fibers have certain sterilization ability or gas pollutant purification function. In addition, there is another type of electret filter material worth mentioning. Electret refers to a dielectric material with a long-term charge storage function. It has the characteristics of being able to generate electrostatic force by itself in the absence of an external electric field. Directly relying on electrostatic force to directly attract charged particles in the air and capture them, or induce neutral particles in the air to generate polarity and then capture them, compared with conventional materials, it has the characteristics of high filtration efficiency and low resistance.2) Activated carbon adsorption technology is one of the most commonly used purification technologies for gas pollutant purification. There are three main development directions: the first is to make new breakthroughs in adsorption strength and adsorption capacity by developing new adsorption materials; Targeted modification treatments such as surface impregnation or halogenation make it characterized by strong adsorption of target gas pollutants; the last one is synergistic with photocatalytic technology, using activated carbon to adsorb and enrich pollutants , to promote the photocatalytic reaction, and achieve a benign purification cycle of adsorption-degradation-adsorption.3) Electrostatic precipitator technology is one of the commonly used particle purification technologies, which has unique advantages compared to HEPA. In practical applications, the main defect that limits its application is that it will generate ozone and cause secondary pollution. Its main development directions: First, by studying the principle of discharge, improving the discharge equipment and reducing the amount of ozone released. For example, the ozone generation rate is related to voltage and discharge structure, and is affected by temperature, and the ozone generation concentration is reduced by technologies such as corona wire heating. The second direction is to achieve the purpose of ozone purification through the coupling of ozone elimination technology and electrostatic dust removal. Some researchers have summarized and compared the methods of controlling ozone concentration. Generally, the methods of eliminating ozone include heating, adsorption, and catalytic reaction. However, both heating and adsorption have various defects, while the catalytic decomposition method has high decomposition rate and long validity period. And other advantages, there is a greater potential for development. For example, the combination of photocatalytic technology and high-voltage static electricity can not only eliminate ozone but also complete the removal of pollutants such as VOCs.4) Plasma purification technology is another kind of potential purification technology. For some complex application environments, such as ship cabins, due to the narrow space, dense personnel and equipment, and insufficient endurance of adsorbent materials, plasma purification technology with strong degradation ability is suitable. The theoretical reaction of plasma purification technology is complex, and the influencing factors are diverse, so it has strong research value. Its development direction: one is to improve the degradation efficiency through rational design of generating equipment; the other is to couple with various catalysts, such as adsorbents, metal catalysts and photocatalysts, etc., the purpose is to improve the degradation efficiency of pollutants.Photocatalytic technology is limited by factors such as catalyst contact area, surface wind speed and pollutant concentration, and its purification efficiency is poor when used alone. However, its material has strong plasticity and mild catalytic conditions, and is suitable for use in synergistic coupling with other gas purification technologies.There are three main research directions in adsorption-photocatalysis technology research: First, the selection of catalyst types. At present, for indoor air purification, most of the research still uses TiO2 with broad spectrum purification ability as the test object, and a small amount of other catalyst types and purification methods are used. The second is the selection of adsorbents, which are generally still based on conventional adsorbent materials, such as activated carbon, activated carbon fibers, zeolite, molecular sieves, etc. There are some ceramic carriers and metal-organic frameworks (MOFs), etc.; the third is the way of compounding the two. Taking activated carbon and TiO2 as an example, there are mainly mechanical mixing, carbon dispersed in TiO2 bulk, carbon-coated TiO2 particles, etc., and TiO2 in TiO2. Load on activated carbon. The loading of TiO2 on activated carbon is the most common, and its preparation methods mainly include direct dip coating method, sol-gel method, sputtering method, direct hydrolysis method, solution method, chemical vapor deposition method, etc.The research on low-temperature plasma-photocatalysis technology is still immature and still in the laboratory research stage. Most of the current research on VOCs degradation reactors only selects a specific organic waste gas, and then studies its degradation characteristics under a specific power supply and reactor. The conclusions about the discharge form and reactor structure are often only applicable to the researched exhaust gas or specific applications. Therefore, it is necessary to further optimize the structure of the discharge power source and the reactor, and explore the matching method with general guiding significance between the two. At present, there are many factors that affect the synergistic photocatalytic purification of VOCs by low-temperature plasma, including the structure and parameters of the ion reactor, and the different types of VOCs and catalysts, which all affect the purification efficiency. Therefore, it is necessary to study the purification reaction more systematically, and it is necessary to expand the technology for processing various types of VOCs so as to be closer to practical applications. It is also necessary to analyze the factors affecting purification, and to promote the research and development of reactor structural parameters and new catalysts. Further improve the purification efficiency.

What's Filter Efficiency Filtration Class based on ASHRAE Standard 52.2-2007, EN779-2012,EN1822-2009

Filter Class ASHRAE Standard 52.2-2007, EN779-2012,EN1822-2009

What is the ADVANTAGES of ACMAN Pulse dust collector?

What is the ADVANTAGES of ACMAN Pulse dust collector? Advantages of ACMAN Explosion Proof Dust Collector 1: The dust collector adopts advanced anti-static filter cartridge type, and the dust removal efficiency is as high as 99.9% (0.5um).2:Advanced control technology realizes single-channel and multi-channel backflushing, excellent cleaning effect and beautiful appearance.3:Professionally designed and customized high-speed and large-volume explosion-proof centrifugal fans and advanced impeller design enable each dust collection equipment to generate flow and negative pressure that meet the needs of on-site working conditions, and can meet the continuous and stable dust collection effect in industrial environments. . Low noise, standard flow and pressure, good dynamic balance, no risk of equipment jitter;4:The electric control box adopts well-known explosion-proof electric control box and electrical components, and has the functions of phase loss, overload and overheating protection; 5:The anti-static filter element is made of polyester-coated microporous material, which has the characteristics of waterproof, oil-proof and high-temperature resistance. The cylindrical pleated design has the advantages of small volume and large filtering area. 6:The solenoid valve adopts explosion-proof solenoid valve, which realizes comprehensive explosion-proof in electrical aspect;7:The quick-release filter element design device makes maintenance and replacement very simple and easy to use, and the selection of filter elements is very diverse, and anti-static film, nanofiber, etc. can be selected according to the requirements of use.8:It has compact structure, beautiful appearance, convenient installation, simple maintenance and high dust collection efficiency.9:The whole machine is equipped with an anti-static grounding device, which can conduct static electricity more effectively, avoid the generation of static sparks, and is safe and reliable.10:There are remote model ports, which can be connected to remote control to realize linkage control with factory equipment. Big Airflow Comparison with other dust collector                 ACMAN stainless steel dust collector           ACMAN Carbon steel dust collector 1: Production based on ISO9001 quality system standards, in line with national HJ/T328 standards;Standard national standard cold-rolled sheet laser production, 304 stainless steel δ1.5-2mm, carbon steel δ2mm;2: Outer surface: stainless steel brushed and polished; carbon steel sprayed with plastic, durable;3: The door frames are designed with reinforced pressure resistance, and the 6 access doors all use automotive industry sealing strips;4: The electrical control is carried out in accordance with the GB/T4942 standard, neat and standardized;5: The design of the injection system is perfect, and the injection effect is good;6: One-year warranty for the whole machine, lifetime maintenance, long-term provision of accessories Other brands of dust collector                        Other brands Dust Collector                      Other brands bag dust collector 1: No production standards and specifications, plate splicing production;2: Non-polishing plate, lower tolerance is too large, inferior 304 stainless steel; carbon steel is only artificially painted;3: The door frame sealing strips do not meet the pressure resistance and leakage rate standards, and there is a risk of powder running;4: The production does not meet the electrical specification standards, and there is a risk of leakage;5: Many manufacturers do not make pulse jet systems,6: One-time sale, no after-sale; ACMAN Pulse Dust Collector Details 1: Multiple filter cartridges, larger filter area and higher efficiency;2: Multiple filter cartridges are sprayed in sections, with good cleaning effect and stable resistance;3: The fan is dynamically balanced and calibrated, with low noise, and the overall feeling of welding and polishing is delicate;4: Laser cutting, welding, CNC bending, electrical standardized production;5: The materials are abundant, the accessories are high-quality, the equipment is solid, and the pressure resistance is strong;6: The injection system is professionally designed, the risk of leakage is guaranteed, and the pressure is stable; Other Brand Dust Collector Detail 1: Single filter cartridge, small filter area and low efficiency;2: The design of the injection system is simple, and there is a risk of air leakage and uneven injection. The injection pipe is simply made of pvc, with obvious vibration and short life;3: The fan has no dynamic balance sign, there is a risk of jitter, and the actual air volume differs greatly from the marked air volume, poor welding, and high air leakage rate;4: The wiring is messy, there are potential safety hazards, and the service life is short;

How many types of FILTER ELEMENTS in Industrial dust collectors?

How many types of FILTER ELEMENTS in Industrial dust collectors? Without Filters-Cyclone Cyclone is the most simple dust and gas separation device without filters in dust collection methodsAdvantage: 1: simple structure;                    2: easy to cleaning;                    3: used for powder recycling;                    4: used for pre-treatment collection;                    5: cheap;Disadvantage: 1: efficiency not so high;                        2: big size for big airflow;                         Cartridge Filters Advantage: 1: Big filter area;                    2: PTFE filter high efficiency;                    3: Low price;                    4: Easy to install;                  Disadvantage: 1: Not suitable for abrasive dust ;                  2: Not suitable for high concentration dust ;                  Filter Bags Advantage: 1: Cheap;                    2: Sustain high temperature                         over 280 centigrade ;                                      Disadvantage: 1: Small filter area, big machine space ;                  2: Not suitable for high concentration dust ;                       3: Efficiency not so high;                       4: hard to replace the filters;                       5: short life span; Sinter-plate Filter Elements Advantage: 1: long life span, over 10 years;                    2: Ultra-high efficiency ;                    3: FDA:used for powder recycling;                    4: Washable;                    5: Anti-acid and alkali;Disadvantage: 1:  Can not sustain high temperature;                         less than 80 centigrade.                         Water-Wet Scrubber Advantage: 1: catch sticky dust;                    2: catch dust with sparks ;                    3: catch explosion/flammable dust;                    4: catch odor;                    Disadvantage: 1:  need waste water treatment;

What is the WORKING PRINCIPLE of ACMAN Dust Collector?

What is the WORKING PRINCIPLE of ACMAN Dust Collector? ACMAN Industrial Dust Collectors has a compact design which make the blower, pulse-jet reverse cleaning system, filter elements and dust drawer/dust bin together.When the raw gas come into the air inlet of dust collector, the gas is expanding in the filtration room, and the dust velocity became slow. Because of the gravity, some heavy dust fall into the dust bin; Thanks to the high efficiency filter elements(sinter-plated filters, cartridge PTFE filters, filter bags), the dust is crashed on the filters' surface, and blocked by the filter elements, 0.3-1um dust could be catched by the filters. then the clean air come out of the filters, and then extracted by the centrifugal fan which provide high air flow and high pressure.when the differential pressure between filter surface and atmosthere became high, the filter ventilation quantity became small, the pulse-jet reverse cleaning system start to work, the compressed air backflow sharply in the inner filters, and the dust on the surface of filters is falling down to the dust bin.This is the one working circle of the dust collector machine. Filtration steps Online reverse pulse steps