The fan is allowed to start at full voltage or at reduced voltage, but it should be noted that the current at full voltage starting is about 5~7 times the rated current, and the reduced voltage starting torque is proportional to the square of the current. When the grid capacity is insufficient, the reduced voltage starting should be used. (When the power is greater than 11KW, it is advisable to adopt the step-down starting.) When the fan is in test run, Industrial dust collector company Carefully read the product manual and check whether the wiring method is consistent with the wiring diagram; Carefully check whether the working voltage of the power supply to the fan meets the requirements, whether the power supply is out of phase or in phase, and whether the capacity of the electrical components provided meets the requirements. During commissioning, the number of people shall not be less than two. One person shall control the power supply and the other person shall observe the operation of the fan. If any abnormality is found, stop the machine immediately for inspection; First, check whether the rotation direction is correct; After the fan starts to run, immediately check whether the running current is balanced and whether the current exceeds the rated current; large Industrial dust collector If there is no normal phenomenon, stop the machine for inspection. After five minutes of operation, stop the machine to check whether the fan is abnormal, and start the machine again after confirming that there is no abnormal phenomenon. When the two speed fan is tested, start the low speed fan first and check whether the rotation direction is correct; When starting the high-speed train, the fan must be stopped before starting to prevent the switch tripping and motor damage caused by high-speed reverse rotation. When the fan reaches the normal speed, check whether the input current of the fan is normal, and the operating current of the fan cannot exceed its rated current. If the operating current exceeds its rated current, check whether the voltage supplied to the fan is normal. The motor power required by the fan refers to the higher power required for centrifugal fan and fan box when the air inlet is fully open under certain working conditions. If the air inlet is fully opened for operation, the motor may be damaged. During fan commissioning, it is better to close the valve on the inlet or outlet pipeline of the fan, open the valve gradually after operation until the required working condition is reached, and pay attention to whether the operating current of the fan exceeds the rated current
large Industrial dust collector The wet electrostatic precipitator mainly has two structural forms. One is to use corrosion-resistant conductive materials (which can be non-metallic materials with excellent conductivity or metal materials with corrosion-resistant characteristics) as the dust collector, and the other is to use non-conductive non-metallic materials as the dust collector by forming a conductive water film through water spray or overflow. Wet electrostatic precipitators can also be divided into cross flow type (horizontal) and vertical flow type (vertical) according to the flow direction of waste gas. The cross flow type is mostly plate structure, Huanggang Industrial dust collector The gas flows in and out in the horizontal direction, and the structure is similar to the dry electrostatic precipitator; The vertical flow type is mostly tubular structure, and the gas flow direction is vertical. Generally speaking, the efficiency of vertical flow wet electrostatic precipitator is twice as high as that of cross flow wet electrostatic precipitator under the condition of the same ventilation cross-sectional area. The dust deposited on the electrode plate can be washed down by water. Wet dust removal can avoid the re flying of captured dust and achieve high dust removal efficiency. Since there is no rapping device, the operation is also more reliable. The device that forms conductive film on the surface of the dust collector by means of water spray or overflow water has problems of corrosion, sludge and sewage treatment. It is only used when the dust concentration of the gas is low and the dust removal efficiency is required to be high; The wet electrostatic precipitator using corrosion-resistant conductive materials as dust collector does not need long-term water spraying or overflow water, Industrial dust collector company Regular flushing is only carried out according to the operating conditions of the system, and only a small amount of water is consumed. This part of water can be recycled, and the dust collection system is basically free of secondary pollution.
Main factors affecting the dust removal efficiency of wet electrostatic precipitator. The effect of electrostatic voltage, water volume and dust concentration on wet electrostatic precipitation efficiency is positive, that is, the dust removal efficiency increases with the increase of voltage, water volume and dust concentration. Among them, voltage has the most significant effect on dust removal efficiency, followed by water volume, and dust concentration has the least effect. The combination of static electricity and water mist can significantly improve the dust removal efficiency. The role of water in wet electrostatic precipitation. The water in wet electrostatic precipitator mainly exists as atomized water droplets. According to domestic research, water mist has a series of effects on the improvement of dust removal efficiency of wet electrostatic precipitator, large Industrial dust collector Main mechanism: the water mist can keep the discharge electrode clean and keep the corona vigorous; The mist particles strike the dust collecting electrode to form a thin and uniform water film, Huanggang Industrial dust collector It can prevent the "secondary flying" of low specific resistance dust from tempering high specific resistance dust and prevent the occurrence of "reverse corona"; For the dust with strong viscosity, the electrode can be prevented from sticking; It is also suitable for collecting those flammable and explosive dust. The water mist is sprayed directly to the discharge electrode and corona area, and the discharge electrode also acts as an atomizer. The same power supply can realize corona discharge, water atomization, water mist and dust particle charging, realizing the organic combination of static electricity and water mist. The water mist is directly sprayed to the discharge electrode, which has a high charge. The collision interception, adsorption and coagulation of water mist with high charge mass ratio in the electric field can greatly improve the dust removal efficiency. The water mist strikes the dust collecting electrode to form water flow down, so that the dust collecting electrode is always kept clean, eliminating the vibrating device, and avoiding a series of problems caused by vibrating dust removal in dry dust removal. In the method of spraying water mist to the discharge electrode and corona area to further atomize the water mist, the static electricity does not directly contact the spray device, so there is almost no insulation problem. This method is completely different from the dedusting technology of "corona discharge atomizes water". The latter is almost impossible to insulate due to the direct contact between water and electricity, and it is actually difficult to achieve industrial application. The barbed electrode can produce a strong electrostatic field, and has a good corona discharge capacity. The electrostatic and water mist work together, and has a high dust removal efficiency
The selection of fans Product performance and fan performance listed in the selection table are based on the performance of delivering air under standard conditions. Therefore, when the use condition is non-standard, the H4-72-12 centrifugal fan must convert the use performance into the performance under standard conditions according to the relationship in the table above, and then select according to the performance and selection table. (3) Treatment of excessive or insufficient flow During use, excessive or insufficient flow often occurs. There are many reasons for this phenomenon. If the flow is high and low during use, it is mainly because the resistance in the pipe network is high and low, or the fan works in a non working area. If it is gradually reduced after a long time during use, it is mainly due to pipe network blockage. After the fan is newly installed, the flow is too large or insufficient during the formal operation. The main reasons for this phenomenon are as follows: 1. The actual value of pipe network resistance is too different from the calculated value. In the general pipe network characteristic equation, H=KQ2, if the actual value K of K-resistance coefficient is less than the calculated value K, the flow will increase; If the actual value K is greater than the calculated value K, the flow decreases. See (b) below.
Forecast from domestic market capacity. Huanggang Industrial dust collector company Fans vary greatly according to different pressure and flow requirements. Therefore, the fan demand should be differentiated according to its type and size, and predicted according to the demand of different industries. According to incomplete statistics, the annual average growth rate of national fan output was 13.8% from 1980 to 1996. large Industrial dust collector It is estimated that the total output of wind turbines in China will be 2.6 million to 2.9 million in 2005 and 3.1 million to 3.25 million in 2010. According to the statistics of fan industry over the years, it is predicted that the output of centrifugal compressors will be 1.6 million to 1.8 million in 2005 and 2 million to 2.1 million in 2010; The output of axial compressor is 260000 in 2005, and is expected to reach 360000 in 2010; The market share of turbine compressor and blower will reach about 70% in 2005