Summary of the most thermal power bag composite du

With the increasingly strict national environmental protection standards, the state has issued a new "emission standard of air pollutants for thermal power plants", which puts forward higher emission requirements for new projects. This paper systematically introduces the characteristics, technical ideas and effects of the electrostatic bag composite dust removal technology

1 overview

electrostatic precipitator and cartridge filter are both high-efficiency dust collectors. The two kinds of equipment have their own advantages. Under the working conditions suitable for their own characteristics, they have achieved good practical application results. Electrostatic precipitator is widely used in metallurgy, electric power, building materials and other industries because of its low resistance, strong adaptability to flue gas changes, and less maintenance workload. So far, it is still in a leading position in the field of environmental protection. With the development of economy and technology in China, citizens' awareness of environmental protection has been greatly enhanced, and environmental protection has become a key issue of social concern. The adoption of dust removal equipment with high efficiency and low emission concentration has become the development trend of environmental protection. Therefore, the advantages of cartridge dust removal are significantly displayed. Especially in recent years, the filter cartridge dedusting technology has made great progress in the host structure, filter material performance, automatic control level and adaptability to various working conditions, resulting in the rapid development of many types of rubber fatigue testing machines in the filter cartridge dedusting technology market. According to the control of SO2 by the air pollution prevention and control law and the restriction of dust removal efficiency, the application of electrostatic precipitator becomes difficult and uneconomical, which lays a foundation for the study of the composite integration of electrostatic precipitator and cartridge type dust removal

2 characteristics of electrostatic precipitator and cartridge filter

table:

technical indicators remarks on the performance of electrostatic precipitator remarks on the performance of cartridge filter

large gas volume access

pressure loss PA 100~300pa low operating resistance 150~500pa strong pulse ash cleaning, ensuring the operating resistance

the best operating temperature is C 80 c---400 C 80 c---120 C. When the temperature is high, the charging capacity and the strength of components are significantly reduced, and when the temperature is low, it is easy to condense and produce arc. The maximum service temperature of the filter cartridge at 135 C is completely suitable for the temperature below the dew point

dust removal efficiency 90~97% 99.999%

emission concentration mg/nm 50---100mg theoretical design 5 mg theoretical design

economic indicators

high and low equipment cost

high and low operating costs

difficult and easy maintenance and management

large and moderate floor area

service life 3---5 years overhaul and replacement of filter cartridge

other loads

adaptability

complex structure Ontology (corona electrode, dust collecting electrode, air distribution device, high voltage insulation, ash cleaning mechanism, shell and ash hopper, etc.). Power supply (each electric field needs to be equipped with a set of high-voltage power supply and control device). Simple

dust removal filter cartridge, shell, blowback system (controller, pulse valve, air bag)

secondary pollution, secondary dust free

based on the above indicators, it is not difficult to see that the advantages of electrostatic precipitator in running resistance are also the growth trend of the design team of Shantou isolation building project that year. The existing host structure, large volume in area and high equipment cost. With the national control of atmospheric SO2, the content of SO2 in coal is low, which increases the specific resistance of dust in flue gas and reduces the charging capacity of electrostatic precipitators. In addition, the emission standards are more stringent, such as the internal control emission standard of Shougang 30 mg/nm, so it is difficult for electrostatic precipitators to meet this requirement. Another example: the electric field wind speed of electrostatic precipitator is basically controlled at ≤ 0. 8m/s~≤1。 Between 2m/s, the volume of equipment with too low concentration increases correspondingly, and the discharge concentration with too high concentration does not meet the standard. This hinders the design and development of electrostatic precipitator

correspondingly, the cartridge filter has made great progress in the adaptability of filter material performance to various working conditions, and has solved the problem of humidity Fibrous The filtration of agglomerative dust and the difficulty of dust removal The surface of the filter material is smooth, and its emergence and application are more positive progress. Even the mechanism of bag type dust removal has changed (deep filtration, establishment of the initial layer. To the surface filtration of the initial layer), it has a higher capture rate of fine dust, and the dust is retained on the surface of the filter material, which is easy to peel off, reducing the resistance of the equipment In addition, the pleated filter cartridge is adopted to increase the filtering area, occupy less space, increase the treatment air volume, reduce the filtering air speed, greatly reduce the volume of the equipment, facilitate installation and simple maintenance In addition to the temperature restriction of the existing filter material (the maximum service temperature is 135 C) The technical advantages of cartridge filter have been recognized by many users

3 Effect of electric bag composite dust removal technology

at present, the national energy technology laboratory in the United States has developed a new type of dust collector combined with electric bag, which has been applied in the purification of boiler flue gas in coal-fired power plants. That is to say, we need to track the international level, strive to create in important technical fields, make breakthroughs in areas where we have advantages, and narrow or exceed the gap with foreign advanced levels

electric bag composite dust collector is a new and efficient dust collector through the organic combination of electric dust collector and filter cartridge dust collector. Under the high-voltage electric field, the former electrostatic precipitator uses the ionization of gas, dust and water particles (the inlet humidity of the electrostatic precipitator is required to be ≤ 10%) to obtain ions and charge, and moves to the electrode with opposite polarity under the action of the electric field force, so as to be trapped. Due to the good conditioning of flue gas (temperature, pressure, humidity and other factors), the former electrostatic precipitator can effectively remove more than 80% of the dust. Coupled with the advantages of electrostatic precipitator on the running resistance of all kinds of precipitators, electrostatic bag composite precipitator is complementary in technology

therefore, it is very important to use advanced filter materials for the performance of the later stage pleated filter cartridge

1. The system requires the stability of running resistance. In many cases, low pressure difference can improve production and ventilation and filtration effect

2. Improve the service life of the filter and reduce the replacement times, which can not only ensure continuous trouble free start-up and operation, but also reduce the input of manual labor and maintenance costs

3. Strictly control dust emission and strengthen environmental protection to meet standards

4. The stable operating pressure difference reduces the energy consumption of the fan to varying degrees and saves compressed air for ash cleaning

pleated filter cartridge adopts advanced filter materials. In addition, the scientific structural design has the advantages of easy ash removal, low operating pressure difference and long service life

compared with a single dust removal equipment, the electrostatic bag composite dust removal technology has high dust removal efficiency, and the dust removal efficiency is not affected by dust