By the end of 2013, the installed capacity of electrostatic precipitators in China had exceeded 680 million KW, accounting for nearly 80% of the installed capacity of thermal power in China In order to meet the 'historically strict' emission standard, electrostatic precipitator equipment enterprises improve dust removal efficiency by introducing and innovating new technologies. At present, thermal power plants using wet electrostatic precipitators or high-performance flue gas purification systems using low-temperature electrostatic precipitators have many successful cases at home and abroad, which can ensure that the smoke and dust after wet desulfurization can reach an "ultra clean" emission level of less than 5 mg / m3, which is better than that of natural gas.

As the backbone enterprise of the dust collector industry, Jiangsu Tianjie Environmental Engineering Co., Ltd. first refers to the application of foreign developed countries, and second, it is in line with the use habits of domestic users.

It is understood that both bag type / electric bag filter and electrostatic precipitator are used in thermal power plants in the world, but most of them are electrostatic precipitators. After most European and American power plants such as the United States, Germany and the Netherlands adopt electrostatic precipitator technology, the soot emission concentration can generally be controlled below 20 mg / m3, and some power plants can reach below 10 mg / m3. Most thermal power plants in Asia also use electrostatic precipitation technology. In Japan, the high-performance flue gas purification system widely used in recent years takes the low-temperature electrostatic precipitator as the core equipment, and uses the synergistic effect of wet desulfurization to make the smoke and dust emission less than 5 mg / m3 without using the wet electrostatic precipitator.

In Australia, bag type dust collectors are mostly used because the sulfur content of coal in local power plants is generally low, mostly 0.4% ~ 0.5%, while the content of silica and alumina is about 85%, and the specific resistance of coal ash is high. If electrostatic precipitators are used, the dust removal performance is very poor. In addition, bag dust removal technology is also widely used in Canada and some Europe.

In fact, the game between electrostatic precipitator and bag / electrostatic bag precipitator has never stopped. Generally speaking, the electric dust removal cost is low and the operation and maintenance resistance is low; Bag / electric bag dust removal has high efficiency and large resistance; Electrostatic precipitator is sensitive to the characteristics of smoke and dust, and the suitable range is small; Bag / electric bag dedusting is suitable for any smoke and dust characteristics, but it has poor adaptability to smoke temperature and smoke composition, so it needs high-temperature protection, low-temperature anti condensation and anti-corrosion; The service life of bag filter bag is short, generally no more than 30000 hours. All cloth bags need to be renewed every 3 ~ 4 years, and the cost can be as high as millions of yuan. At this stage and under the current emission standards, the investment of the two is roughly the same, and the operation and maintenance cost of bag / electric bag filter is slightly higher.

Power generation enterprises should choose appropriate dust removal methods

When selecting dust removal methods and technical routes, power generation enterprises should adjust measures to local conditions and coal conditions. They need to evaluate which is appropriate according to their own production and the characteristics of the two technologies.

Electrostatic precipitator, which has a history of one hundred years in the west, has also developed for more than 30 years in China. Its technology is relatively mature and can achieve energy conservation and emission reduction under low emission conditions. It is one of the effective dust removal equipment suitable for China's national conditions. Under the requirements of the new emission standards, it has taken the lead in the market.

As a high-efficiency dust removal equipment, the dust removal efficiency of bag / electrostatic bag filter is not affected by the characteristics of smoke and dust, especially as an efficient capture means of fine particles (PM10, PM2.5). With the development of manufacturing technology and the opportunities of emerging industries, the market prospect can not be underestimated. Power generation enterprises have more choices whether to use electricity or bags, or electricity + bags. They use market competition to promote the development of dust collector industry technology and accelerate the adjustment of industrial structure.

With the successful operation of China's first newly-built near zero emission coal-fired unit and the first modified ultra clean emission coal-fired unit, the question of whether the electrostatic precipitator equipment suspected by public opinion can meet the new emission standards has been clarified. High frequency power supply technology, rotating electrode electrostatic precipitator technology, low-temperature electrostatic precipitator technology, electrocoagulation technology, breeze electrostatic precipitator technology and other new technologies that help improve the efficiency of dry electrostatic precipitators, as well as the end check wet electrostatic precipitator technology, began to help coal-fired power plants create one myth after another under the extremely harsh low emission requirements. With the transformation of some large units, the smoke and dust emission is stable below 3mg / m3, which is far lower than the special emission limit of air pollutants of gas turbine. It can be said that the new technology of electrostatic precipitator took the lead in opening the era of ultra clean emission.

Some experts pointed out that domestic backbone enterprises have carried out independent innovation and research and development through the introduction of technology and according to the national conditions. At present, the dust collector technology and product quality have reached the international advanced level, and all the electrostatic precipitators have been localized. In China's environmental protection industry, electrostatic precipitator industry is a competitive industry that can compete with international manufacturers. China is already a large producer of electrostatic precipitator equipment, ranking first in science and technology in this field.