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Paper on electrostatic dust removal technology
Electrostatic precipitation is a technology that uses the strong electric field generated by high voltage power supply to produce corona discharge, so that suspended dust particles can be separated from gas under the action of electric field force. The following is my carefully recommended paper on electrostatic precipitation technology, I hope you can feel it!

Study on the application of new electrostatic dust removal technology in emission reduction and energy saving

This paper expounds the application research of new technology of emission reduction and energy saving electrostatic precipitator from three aspects: the development status of electrostatic precipitator technology, new technology of emission reduction and energy saving electrostatic precipitator and other technologies.

Emission reduction; Energy saving; Electrostatic dust removal technology; Application; study

China Library Classification Number: TE08 Document Identification Number: A

I. Introduction

With the continuous development of science and technology, in order to better save energy and reduce pollutant emissions, the new electrostatic dust removal technology of energy saving and emission reduction has been widely used.

Second, the development status of electrostatic precipitator technology

The comprehensive and systematic research and development of electrostatic precipitator technology in China began in the 1960s. Before 1980, China was still in a very backward position in the international electrostatic precipitator field. Since the reform and opening up, China's national economy has continued to grow at a high speed, and environmental protection has become more and more important for the sustainable development of the national economy. Driven by the interests under the market economy, many large and medium-sized environmental protection industries in China have continuously increased their investment in the research and development of electrostatic precipitator technology, and their applications have been greatly developed. The country has even incorporated the high-efficiency electrostatic precipitator technology into it? Seven or five? National key projects. Through the digestion, absorption and reasonable reference of imported technology, by the end of 1990s, the technical level of electrostatic precipitator in China had basically caught up with the international advanced level in the same period.

After entering 2 1 century, China has put? Vigorously promote scientific and technological progress, strengthen environmental scientific research, and actively develop environmental protection industries? As an important policy related to economic development, environmental protection industry has received further attention. With the continuous improvement of national requirements for pollution control, the requirements for dust emission have also been greatly improved. As one of the main equipment to control air pollution and solve the contradiction between environmental protection and economic development, the application technology of electrostatic precipitator has been further developed rapidly.

At present, electrostatic precipitator has been widely used in thermal power generation, steel, nonferrous metallurgy, chemical industry, building materials, machinery, electronics and many other industries. As a big country of electrostatic precipitator in the world, China has entered the international advanced ranks not only in quantity but also in technical level. The technology of electrostatic precipitator, from equipment body to computer-controlled high and low voltage power supply, as well as insulation fittings, vibration devices, polar plates and wires, has all been localized, and some products have been exported to more than 30 countries and regions.

Before 1980, the scale of electrostatic precipitators in China was mostly below 100m2, and the industry share was 32% in nonferrous metallurgy industry, 30% in steel industry, 0/8% in building materials industry, 8% in power industry, 5% in chemical industry, 4% in light industry and 0% in other industries.

With the rapid development of China's economy, especially the development of electric power and building materials cement industry has reached an unprecedented level. By the mid-1990s, the professional pattern of electrostatic precipitator industry has changed: electric power industry accounts for 72%, building materials cement industry accounts for 17%, steel industry accounts for 5%, nonferrous metallurgy industry accounts for 3%, and other industries account for 3%. At present, the consumption of electrostatic precipitator in thermal power generation industry has accounted for more than 75% of the national total, and 648m2 electrostatic precipitator has been successfully operated in 100MW thermal power plant. In the chemical industry, due to the influence of international sulfur price, the number of enterprises adopting sulfur-based sulphuric acid process instead of pyrite-based sulphuric acid process rose sharply in the mid-1990s, resulting in a sharp decline in the industry share of electrostatic precipitators, and there was no sign of bottoming out until the last two years.

Three, emission reduction and energy saving new electrostatic dust removal technology

1, waste heat utilization and efficiency improvement technology

In thermal power generation, due to the coarsening of pulverized coal, excessive water content of coal and other factors, it is easy to cause the flue gas temperature discharged from the boiler to be too high, which greatly reduces the working efficiency of electrostatic precipitator. The influence of high smoke temperature on electrostatic precipitator is mainly manifested in:

1) The high temperature flue gas will increase the flue gas quantity, and at the same time increase the electric field wind speed, which will shorten the treatment time of flue gas passing through the electrostatic precipitator and reduce the dust removal efficiency.

2) High temperature flue gas will also reduce the breakdown voltage of electric field and increase the gap between gas molecules, which is not conducive to the collision between electrons and them, thus increasing the ionization effect and reducing the dust removal efficiency.

3) It is easy to form back corona (partial discharge caused by dust with high specific resistance on the electrode plate of the dust collector), and the dust will fly for the second time in the morning, reducing the dust removal efficiency.

2. High frequency power supply technology

The power supply used in thermal power plants is mainly the conventional power supply with power frequency band of 50Hz, while the high-frequency power supply is applied to electronic and microelectronics technology, and the waveform conversion can meet the requirements of electrostatic dust removal power supply, and it has many advantages:

1) to improve efficiency. If the electrostatic precipitator adopts high-frequency power supply, the efficiency of electrostatic precipitator can be doubled and the emission of flue gas can be reduced by using the electrical characteristics and discharge performance of high-frequency power supply.

2) Save energy. Using some characteristics of high frequency power supply, the efficiency factor of electrostatic precipitation can be increased to 0.9, which can save energy.

3) Small size and convenient use. Due to the limitation of technology, it is difficult to further reduce the volume of ordinary power supply on the existing basis. The high-frequency power supply is very small because of the integration technology of transformer and control system, so it can be considered to be installed at the top of electrostatic precipitator when installing. The characteristics of integration also determine that it can use fewer cables and save more space.

4) environmental protection. High frequency power supply adopts three-phase power supply mode, which has little influence on the whole power grid. Its biggest feature is no phase loss and no pollution. At the same time, the functions of short circuit, open circuit and over-temperature protection are added in the circuit design, which can be used under very harsh conditions.

3, sulfur trioxide conditioning technology

Sulfur trioxide is one of the main pollutants in the flue gas of thermal power plants. Therefore, if we can reduce the emission of sulfur trioxide in electrostatic dust removal technology, or further reduce the pollution of sulfur trioxide to the environment, we can meet the national emission reduction requirements. Sulfur trioxide flue gas conditioning technology is to combine a certain amount of sulfur trioxide with a small amount of moisture in flue gas by certain means to form acid aerosol, which is easily adsorbed on the dust surface when passing through the dust collector, thus achieving the efficiency of electrostatic dust removal.

4, low secondary dust technology

Low secondary dust removal technology mainly solves the problem of low dust removal efficiency caused by secondary dust generated by flue gas under the action of electric wind in the process of electric dust removal. Low secondary smoke technology mainly includes the following measures:

1) Improve the rapping mechanism inside the electrostatic precipitator, optimize the rapping working procedure, remove unnecessary rapping through reasonable configuration of rapping intensity, reduce the concentration of secondary dust, and make the dust gathered on the electrode plate condense and fall off.

2) Improve the electric field to overcome the secondary dust at high speed. At present, the improvement of electric field mainly includes the use of high-frequency power supply to reduce corona blockage and increase the working efficiency of electric field; Adding a variable resistance flow grid in the electric field to reduce the amount of dust; Increase the electric field area, expand the blocking range of flue gas circulation, and further reduce the wind speed.

5. Air distribution technology

When improving the electric dust removal technology in thermal power plant, the composition of smoke and dust was studied, and a new technology of airflow distribution appeared. This technology considers the influence of airflow distribution and concentration distribution on emission in large electrostatic precipitator.

In order to solve the influence of uneven air distribution, the air distribution technology starts with the original detection and analysis, and studies the internal structure of electrostatic precipitator and the installation of air distribution device in the air duct. After a series of experiments, find out the reasons that affect the air distribution, so as to prescribe the right medicine. This technology mainly finds out the correction scheme through complex operation, which can effectively ensure the uniform distribution of airflow in the airflow chamber and maximize the efficiency of electrostatic precipitation.

Fourth, other technologies.

1, electromechanical multi-element composite double-zone electrostatic precipitator technology

The charging and dust collection functions of the conventional electrostatic precipitator are completed in the same electric field, and the strength of the electric field is often limited by the charging voltage, which makes the electrostatic precipitation effect unable to get the best play. In this paper, a new product technology of electromechanical multi-element composite double-zone dust-collecting electric field is proposed, and the anode and cathode are arranged in different zones. According to the design requirements, 2~3 groups of charging and dust collecting units can be arranged in a compound staggered way along the length direction of the electric field.

2. Energy-saving electronic control technology to improve efficiency

Mainly through the analysis, induction and summary of various operation data under different coal types, different working conditions and different load conditions, the relationship between the dynamic volt-ampere curve family of electric field and the change of working conditions characteristics is comparatively analyzed, and the mathematical model for the analysis and diagnosis of different working conditions characteristics is established. Based on this model, the back corona index and positive corona index of electrostatic precipitator can be calculated reliably, which correctly reflects the working condition and changing trend of the whole electrostatic precipitator. Combined with boiler load, flue gas quantity, flue gas temperature, soot blowing signal and other signals; Automatic analysis and diagnosis of electric field conditions; Real-time automatic selection of power duty ratio and working parameters of high-voltage power supply; Realize comprehensive energy saving, and make the electrostatic precipitator always run in the state of minimum power consumption and highest efficiency.

3. Wet electrostatic precipitator technology

Wet electrostatic precipitator adopts the method of washing the electrode, which can ensure the cleanliness of the electrode, effectively capture fine dust and remove SO3 and some heavy metals. , mainly used for dust removal and other normal temperature working conditions in metallurgical environment. After being used for wet desulfurization of coal-fired boilers, it can capture fine dust escaped by PM2.5, effectively solve problems such as gypsum rain, and realize near zero emission. However, attention should be paid to solving the problems of equipment anticorrosion and wastewater reuse.

4. Full bag technology and electric bagging technology

The whole bag dust removal process is not only technically feasible, but also has the advantages of saving investment, occupying less land and low operating cost. It is a new technology with China characteristics and a typical energy-saving and environmental protection project. The transformation of electrostatic precipitator into electric bag precipitator has improved the dust removal efficiency of electrostatic precipitator. Specific resistance? Great influence, low dust removal efficiency.

Verb (abbreviation of verb) conclusion

Generally speaking, the continuous development and application of various new technologies have greatly promoted the development of energy-saving and emission-reduction technologies, reduced the emission of particulate pollutants to a certain extent, and promoted the improvement of living environment.

refer to

[1] Hu? Study on the application of new technology of emission reduction and energy saving electrostatic precipitation [J] Theoretical research on urban construction (electronic version) -20 13, No.9-

[2] Luo Rusheng, Liao Zeng 'an, Application and analysis of new technical transformation of electrostatic precipitator to meet new standards [J] Electric Power Technology and Environmental Protection -20 12, No.4-

[3] Evaluation, research and application of electrostatic dust removal technology in Gu coal-fired power plant [J] Application of electric power technology -20 13 Phase 3-

[4] Application analysis of Wenjie's new electrostatic dust removal technology for emission reduction and energy saving [J] Architectural heritage -20 13, 17-

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