How are dust collectors classified, large Centrifugal fan Do you know how to distinguish it and how to define its economic type? Let's talk about it from these aspects. 1. Dust removal efficiency. Anshun Centrifugal fan Dust removal efficiency refers to the ratio of the amount of dust collected by the dust collector to the amount of dust entering the dust collector. According to the total dedusting efficiency, the dedusters can be divided into: low efficiency dedusters (50~80%), medium efficiency dedusters (80~95%) and high efficiency dedusters (more than 95%). 2. Dust removal resistance. The resistance indicates the pressure loss when the airflow passes through the dust remover. According to the resistance, dust collectors can be divided into low resistance dust collectors (Δ P<500Pa), medium resistance dust collectors (Δ P=500 ～ 2000Pa) and high resistance dust collectors (Δ P=2000 ～ 20000Pa). 3. Economy. Economy is one of the important indexes for evaluating dust remover, which includes equipment cost and operation and maintenance cost of dust remover. Among all kinds of dust collectors, the equipment cost of electrostatic precipitator is the highest, followed by bag type dust collector, Venturi tube dust collector, cyclone dust collector is the lowest electrostatic precipitator: the dust removal efficiency is high, generally above 99%, and the design efficiency is up to 99.99%. The wet dust collector is commonly known as "water dust collector" : The filtration efficiency can reach more than 85%, and the integrated desulfurization and dust remover of stone water film+swirl plate>>about 80% of desulfurization and dust removal can reach as high as about 95%.
Gas compression and gas transmission machinery is a machine that converts rotating mechanical energy into gas pressure energy and kinetic energy and transports gas. The main structural components of the fan are impeller, casing, air inlet, support, motor, pulley, coupling, silencer, transmission parts (bearings), etc. large Centrifugal fan The unpowered fan uses the air thermal convection caused by the natural wind force and the indoor and outdoor temperature difference to drive the turbine to rotate, thus using the centrifugal force and negative pressure effect to exhaust the indoor stale hot air. Anshun Centrifugal fan company The fan is related to the transmission and distribution energy consumption of the system, and is a very critical part of building energy conservation. According to the fan inspection conducted by the National Air Conditioning Equipment Quality Supervision and Inspection Center for many years, many fans have problems under rated conditions, so it is necessary to produce and manufacture fans in strict accordance with product standards. large Centrifugal fan At the beginning of the fan operation, the vibration of the bearing is very small, but with the extension of the operating time, the dust in the fan will be unevenly attached to the impeller, gradually destroying the dynamic balance of the fan, making the bearing vibration gradually increase. Once the vibration reaches the maximum allowable value of 11mm/s of the fan (the maximum allowable value expressed by the amplitude value is as follows), The fan must be shut down for repair (dust accumulation shall be removed and dynamic balance shall be redone). Because it is very dangerous at this time, users must not use it forcibly. When the fan vibration is close to the dangerous value, the vibration measuring instrument will give an alarm.
Selection and application of fan performance (I) Description of fan performance: 1. № 10, 12, 16, 20 are converted according to dimensionless performance of № 10 model. 2. № 5, 6, 8 are converted according to dimensionless performance of № 5 model. 3. № 5 and below shall be determined according to the performance of the measured prototype. Note: According to the dimensionless performance curve conversion formula, total pressure H=ρ u2 H (Pa) flow Q=900 π D22 uQ (m3/h) shaft power N=N × D22u3 ρ/4000 (kw), where D2 - impeller outer diameter (m) u - impeller outer edge linear speed (m/s) ρ - gas density (Kg/m3), the required power rate shall be based on shaft power plus mechanical loss and motor reserve. 4. The solid line is № 5 model, and the dotted line is № 10 model. The performance of the fan is expressed by the flow, total pressure, main shaft speed, shaft power, efficiency and other parameters of the fan, and there are certain relationships between the parameters, which are listed in the following table. The relationship of fan performance parameters changes density ρ, speed n changes speed n, atmospheric pressure P, gas temperature t Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 ρ 1/ρ 2 N1/N2=(n1/n2) 3 ρ 1/ρ 2 η 1=η 2 Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 (P1/P2) (273+t2/273+t1) N1/N2=(n1/n2) 3 (P1/P2) (273+t2/273+t1) η 1=η 2 Note: 1. In the middle, Q represents flow (m3/h), H represents total pressure (Pa), N Represents shaft power (kw), η represents total pressure efficiency, ρ represents density (kg/m3), t represents temperature (℃), n represents speed (r/min), and P represents atmospheric pressure (Pa). 2. The footnote symbol 2 indicates the known performance and related parameters, and the footnote symbol 1 indicates the required performance and related parameters. （
The wet electrostatic precipitator is a new kind of dust removal equipment used to treat micro dust and micro particles, large Centrifugal fan It is mainly used to remove dust, acid mist, water droplets, aerosols, odor, PM2.5 and other harmful substances in humid gases, and is an ideal equipment for controlling atmospheric dust pollution. The wet electrostatic precipitator is usually referred to as WESP, which has the same basic principle as the dry electrostatic precipitator. It goes through three stages: charging, collection and dust removal. The principle of wet electrostatic precipitator is the same as that of dry electrostatic precipitator, Anshun Centrifugal fan The dust is charged by high-voltage corona discharge, and the charged dust reaches the dust collecting plate/tube under the action of electric field force. The dry electrostatic precipitator mainly deals with dry gas with very low water content, while the wet electrostatic precipitator mainly deals with wet gas with high water content or even saturation. There is a big difference between WESP and DESP in the way of removing the dust collected on the dust collecting plate/pipe. The dry electrostatic precipitator generally uses mechanical rapping or acoustic cleaning to remove the dust on the electrode, while the wet electrostatic precipitator uses regular flushing to remove the dust along with the flow of flushing fluid
Correct maintenance is an important guarantee for the safe and reliable operation of the fan and the improvement of its service life. Therefore, Centrifugal fan company When using fans, full attention must be paid. Impeller maintenance: at the initial stage of impeller operation and during all regular inspections, whenever there is an opportunity, the impeller must be checked for cracks, wear, dust and other defects. The impeller must be kept clean whenever possible, large Centrifugal fan The steel wire brush shall be used regularly to remove the dust and rust on the impeller. As the travel time increases, the dust can not be evenly attached to the impeller, which will cause damage to the balance of the impeller and even cause rotor vibration. As long as the impeller is repaired, it needs to be dynamically balanced again. If possible, the portable trial dynamic balancing instrument can be used for on-site balancing. Before dynamic balancing, check whether all fastening bolts are tightened. Since the impeller has been operating in an unbalanced state for a period of time, these bolts may have become loose. Bearing maintenance: frequently check the oil supply of bearing lubricating oil. If the box leaks oil, tighten the bolts of the end cover a little. If this is not enough, you may have to use new sealing packing. When the bearing lubricating oil is in normal use, it should be replaced at least once every six months. When it is used for the first time, it should be done after 200 hours of operation. The second oil change should be done in 1 to 2 months. After that, the lubricating oil should be checked once a week. If the lubricating oil does not deteriorate, the oil change can be extended to 2 to 4 months. The specified brand of lubricating oil (specified on the general drawing) must be used when replacing, The old oil in the oil tank shall be completely drained and cleaned before new oil can be filled. If the fan bearing needs to be replaced, pay attention to the following matters: before installing the new bearing, the bearing and bearing box must be very clean. Place the bearing in the oil with a temperature of about 70~80 ℃ and heat it before installing it on the shaft. Do not force assembly to avoid damaging the shaft. Maintenance of other supporting equipment: see the respective user manual for the maintenance of various supporting equipment, including motors, electric actuators, instruments, meters, etc. These operating instructions are provided by each supporting manufacturer. The manufacturer will pack these instructions together and provide them to the user
Wet dust remover is a device that uses the action of water or other liquids and dusty gases to remove dust particles. When dust particles meet with sprayed water droplets, water films or wetted walls and devices The process of wetting, condensation, diffusion and sedimentation takes place, so it is separated from the gas to purify the gas. Anshun Centrifugal fan company It is characterized by purifying dust at the same time It can also purify gas, large Centrifugal fan When the flue gas contains combustible components, the use of wet dust collectors can avoid equipment explosion, and the dust removal effect can generally meet the environmental protection requirements. The equipment is small and the investment is relatively low. Therefore, there are three wet dust collectors used in dust removal projects in mining, metallurgy, machinery, light industry, building materials and other industries. Sludge containing sewage must be treated, otherwise secondary pollution may occur, Therefore, it is not widely used as dry dust collector. There are many types of wet dust collectors. According to their structures, there are the following types: ① gravity spray wet dust collectors - spray scrubbing towers; ② Cyclone wet dust collector - cyclone water film dust collector, water film dust collector; ③ Self excited wet dust collector - impulse dust collector, water bath dust collector; ④ Packed wet dust collector - packed tower, turbulent ball tower; ⑤ Foam wet dust collector - foam dust collector Cyclone dust collector, leaky plate tower; ⑥ Venturi wet dust collector - Venturi tube dust collector; ⑦ Mechanical induction wet dust collector - water wheel dust collector.
