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. （

Main working principles of wet electrostatic precipitator: major Centrifugal fan Spray the water mist to the discharge electrode and corona area, the water mist will split and further atomize after being charged in the powerful corona field formed by the barbed electrode, and the collision interception, adsorption and coagulation of electric field force and charged water mist will jointly trap the dust particles, and finally the dust particles will reach the dust collector under the drive of electric field force and be trapped. The water forms a continuous water film on the dust collecting electrode, and the captured dust is washed into the ash hopper and discharged with water. Operating principle of wet electrostatic precipitator. The dedusting process of electrostatic precipitator can be divided into four stages: gas ionization; The dust is charged with ions; Charged dust moves towards the electrode; Remove the dust on the electrode. Only the objects removed by wet electrostatic precipitation are dust and droplets, but their working principles are different due to the differences in physical characteristics between droplets and dust. In principle, Jiangxi Centrifugal fan First of all, the existence of water droplets has an impact on the electrode discharge. To form emitting ions, free electrons in the metal electrode must obtain enough energy to overcome the ionization energy and cross the surface barrier to become emitting electrons. It is an effective measure to reduce the surface barrier by bringing water on the electrode surface. After the metal surface is covered with water, the original "metal air" interface is divided into "metal water" interface and "water air" interface. The potential barrier of the latter two interfaces is much lower than that of the former interface. In this way, after the metal surface is filled with water, the original high barrier will be divided into two low barriers, which will greatly weaken the blocking effect of the surface barrier on free electrons and make electrons easy to launch. In addition, Centrifugal fan company Under the action of electric field, various impurity ions in water can easily cross the surface barrier and become emission ions. All of these have changed the electrode discharge effect, enabling corona discharge under low voltage. Secondly, due to the existence of water droplets, the resistance of water is relatively small. When water droplets combine with dust, the specific resistance of dust with high specific electricity decreases, so the working state of wet electrostatic precipitator will be more stable; In addition, since the wet electrostatic precipitator is washed by water flow and has no rapping device, it will not produce secondary dust.

Jiangxi major Centrifugal fan WESP has the advantages of high dust removal efficiency, small pressure loss, simple operation, low energy consumption, no moving parts, no secondary dust, low maintenance costs, short production downtime, can work below the flue gas dew point temperature, can be combined with other flue gas treatment equipment due to its compact structure, and diversified design forms. The wet electrostatic precipitator uses liquid to wash the dust collecting electrode surface for dust removal, which can effectively collect fine particles (PM2.5 dust, SO3 acid mist, aerosol), heavy metals (Hg, As, Se, Pb, Cr), organic pollutants (polycyclic aromatic hydrocarbons, dioxins), etc. After the wet electrostatic precipitator is used, the smoke and dust emission in the wet flue gas can reach 10mg/m3 or even below 5mg/m3, and the dust collection performance has nothing to do with the dust characteristics, Centrifugal fan company It is suitable for the treatment of wet flue gas, especially for the treatment of dusty flue gas after wet desulfurization in power plants and steel plants. However, the equipment investment cost is high, and it needs to be used together with other dedusting equipment. Its investment, technical economy and operating cost should be evaluated from an overall perspective.

major Centrifugal fan The fan is a kind of driven fluid machinery, which relies on the input mechanical energy to increase the gas pressure and discharge gas. Fan is the abbreviation of Chinese custom for gas compression and gas transmission machinery. Generally speaking, fans include fans, blowers, and wind turbines. Jiangxi Centrifugal fan company Fans are widely used for ventilation, dust discharge and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings, as well as ventilation and induced draft of boilers and industrial furnaces; Cooling and ventilation in air conditioning equipment and household appliances; Drying and delivery of grain, wind source of wind tunnel and inflation and propulsion of hovercraft

The wet electrostatic precipitator is a new kind of dust removal equipment used to treat micro dust and micro particles, major 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, Jiangxi 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