New electric dust removal technology opens the era of ultra-clean emissions

"By the end of 2013, China's installed capacity of electrostatic precipitators exceeded 680 million kilowatts, accounting for nearly 80 percent of the country's installed thermal power capacity. In order to meet the "strictest ever" emission standards, electric dust removal equipment enterprises through the introduction and innovation, the application of new technology to improve dust removal efficiency. At present, thermal power plants using wet esp or high performance flue gas purification system using low and low temperature ESP have many successful cases at home and abroad, which can ensure that the flue gas after wet desulphurization is less than 5 mg/m3 'superior to the ultra-clean' emission level of natural gas. With the successful operation of shenhua Guohua Zhoushan Power Plant and other near-zero emission projects, the esp industry has taken the lead in ushering in a new era of ultra-clean emissions." Zhao Qinxia, professor-level senior engineer and deputy general manager of Zhejiang Feida Environmental Protection Technology Co., LTD., told China Power News.

Electric bag dust removal technology varies

"As the backbone enterprise of dust collector industry, Feida environmental protection is still focused on improving the efficiency of electric dust removal equipment. One is to refer to the application situation of foreign developed countries, and the other is in line with the use habits of domestic users." Zhao Qinxia said.

It is understood that the international thermal power plants using bag/electric bag dust collector and electrostatic precipitator are, but still in the majority of electrostatic precipitator. The United States, Germany, the Netherlands and other European and American countries most power plants using electric dust removal technology, soot emission concentration can be controlled in 20 mg/m3 below, some power plants to 10 mg/m3 below. Asian thermal power plants, also mostly use electric dust removal technology. In Japan, the high-performance flue gas purification system widely used in recent years, with low temperature electrostatic precipitator as the core equipment, and using the synergistic effect of wet desulfurization, under the condition of no use of wet electrostatic precipitator, can make soot emission less than 5 mg/m3.

The reason is that the coal burning in local power plants generally contains low sulfur content, mostly 0.4% ~ 0.5%, while the content of silica and trialumina is about 85%. The coal ash specific resistance is high, and the dust removal performance is poor if the dust collector is used. In addition, Canada and some European countries also more bag dust removal technology.

In fact, electrostatic dust and bag/electric bag dust better game has never stopped. In general, the electric dust removal resistance is small, low operation and maintenance cost; Bag/electric bag dust removal efficiency is high, large resistance; Electric dust removal is sensitive to dust and dust, and its suitable range is small. Bag/electric bag dust removal is suitable for any smoke and dust characteristics, but it has poor adaptability to smoke temperature and flue gas composition, so it needs to be protected at high temperature, prevent condensation at low temperature and prevent corrosion; Bag filter bag life is short, generally not more than 30,000 hours, every 3 ~ 4 years the bag needs to be updated once, the cost can be as high as millions of yuan. At the present stage, the current emission standards, the two investment is roughly the same, operation and maintenance costs, bag/electric bag dust collector slightly higher.

Power generation enterprises should choose appropriate dust removal methods

"Power generation enterprises in the selection of dust removal methods and technical routes, to adapt to local conditions, due to coal conditions, according to their own production and the characteristics of the two technologies to evaluate which one is appropriate." Said Professor Gao Xiang, deputy director of energy Engineering department at Zhejiang University.

In the west through a hundred years of history of electric dust, in China has been developed for more than 30 years, relatively mature technology and can achieve low emissions under the condition of energy conservation and emission reduction, is the most suitable for China's national conditions of the most effective dust removal equipment, in the new emission standards, occupy the market opportunity.

And bag/electric bag dust collector as an efficient dust removal equipment, dust removal efficiency is not affected by the characteristics of dust, especially as a means of efficient collection of fine particles (PM10, PM2.5), with the development of manufacturing technology, with the opportunities of emerging industries, the market prospect can not be underestimated. With "electricity" or "bag", or "electricity + bag", power generation enterprises have more choices, promote the development of dust collector industry technology by means of market competition, accelerate the adjustment of industrial structure.

With the successful operation of the first newly built "near zero emission" coal-fired unit and the first reformed "ultra net emission" coal-fired unit in China, the question of "whether electric dust removal equipment can meet the new emission standards", which had been suspected by public opinion, has been clarified. High-frequency power supply technology, rotating plate electric dust removal technology, low temperature electric dust removal technology, and electric condenser technology to improve the efficiency of dry electrostatic precipitator, and finally check the wet electric dust technology began to help coal-fired power plants under the extremely harsh low emission requirements to create one myth after another. The smoke and dust emission of shenhua Guohua Zhejiang Zhoushan Power Plant no.4, Guangzhou Hengyun Power Plant No.9, Zhejiang Energy Group Jiaxing Power Plant No.7, No.8 are stable below 3 mg/m3, far lower than the national "special emission limit of gas turbine air pollutants". It can be said that the new technology of electric dust removal has taken the lead in opening the era of ultra-clean emissions.

Some experts point out that the domestic backbone enterprises through the introduction of technology, according to the national conditions of independent innovation research and development, at present the dust collector technology and product quality has reached the international advanced level, the latest technology of electrostatic precipitator has been all made in China. In China's environmental protection industry, electrostatic precipitator industry is a competitive industry that can compete with international manufacturers at present. China has been the world's largest producer of electric dust removal equipment, in the field of science and technology in the forefront of the world.

Coulomb electrostatic precipitator is a kind of high efficiency and energy saving electrostatic precipitator, which greatly improves the efficiency of electrostatic precipitator. Coulomb esp is 30% more efficient than ordinary esp.