The "Air Pollutant Emission Standards for Thermal Power Plants", which will be implemented on July 1 this year, imposes strict requirements on the emission standards of existing thermal power plants. To this end, most of China's thermal power plants have to carry out large-scale environmental protection transformation, and the current dust removal technology has many problems such as input costs and technical bottlenecks, which restricts the pace of power plant renovation and upgrading.
This is called “the most stringent standard in history” and requires the minimum standards for dust, SO2, NOx and smoke blackness of existing thermal power boilers and gas turbines to be reduced from 50mg/m3 to 30mg/m3, and the key area is 20mg/ M3. This means that in the remaining short period of 5 months, most thermal power plants must carry out technical transformations such as desulfurization, denitrification and dust removal, which not only has a huge transformation cost, but also has a bottleneck in current technology.
"At present, the power plant is undergoing a comprehensive technical upgrading and upgrading, and it is expected that all emissions will reach the latest standards by July 1." Fang Hong, director of the Wuhan Qingshan Thermal Power Plant Science and Technology Environmental Protection Center, told reporters, "This depends on a large amount of capital investment." Qingshan Thermal Power Plant is affiliated to Guodian Group. It has two 350MW-class and two 220MW-class cogeneration units. It is currently undergoing desulfurization and denitrification and dust removal facilities. However, the total investment of nearly 300 million yuan has become a huge burden.
According to the data of China Electricity Council, the average denitration cost of new units in China is about 1.2 points/kWh, and the active units are about 1.5 points/kWh; some specially designed units may be higher than 2 points/kWh. “In addition to the one-time up-front investment in the desulfurization and denitrification equipment transformation, the huge operating cost in the later period is also one of the most worrying costs for the power plant,” said the industry source.
Not only is the cost high, but it is also difficult to achieve technical standards. From the effect point of view, the use of bag dust removal, electric bag composite dust removal or moving electrodes, high-frequency power supply and other new processes, due to the lack of a wide range of applications, the technology is still unstable. “When the bag is used for a period of time, it will be damaged, and the dust removal effect will be reduced. After three or five years, it will have to be replaced again, and then put it again.” Fang Hong said.
For some old power plants, the effects of current equipment and technical processes have reached the top. According to data released by China Electricity Council, as of the end of 2012, at least 72% of active units need to complete denitration and other smog reforms, which in turn requires longer cycles and even shutdowns to affect the power generation of power plants.
In order to solve this series of problems, the State Key Laboratory of Coal Combustion of Huazhong University of Science and Technology has invented the bonding dust removal method through 13 years of research. This method uses the new coal-fired PM2.5 emission control technology to promote the agglomeration of PM2.5 into large particles without increasing the existing dust removal equipment and parameters, without increasing the large equipment, without requiring a large investment. There is removal efficiency of the dust removal equipment.
Professor Zhang Junying, one of the main researchers of the technology and the deputy director of the State Key Laboratory of Coal Combustion at Huazhong University of Science and Technology, said that most of the power plants in China have installed electrostatic precipitators. If combined with the dust removal method, the dual technology combined effect is not only effective. Better, and, most convenient and fast, it also saves costs such as large-scale technological transformation.
At present, the technology has obtained two national invention patents, two provincial and ministerial awards, and two consecutive grants from the Ministry of Science and Technology "863" project, with market promotion and application conditions.
China is the world's largest coal producer and consumer. The proportion of coal in primary energy consumption is as high as 69.4%. The ultrafine particulate matter emitted by coal-fired power stations is the main source of atmospheric particulate pollutants in China, and it also induces global climate change and smog events. And important factors such as major environmental events such as ozone depletion.
Faced with the implementation of new emission standards from July 1 this year, time is tight, tasks are heavy, and technology and financial pressures are enormous. Professor Zhang Junying suggested that coal-fired power plants should systematically analyze the characteristics of particulate matter emissions, select practical and economically viable technologies, start upgrading and upgrading dust removal equipment as soon as possible, and strive to complete technical transformation on time.
Zhang Junying said that there may be some technical improvements and process adjustments in the implementation of the technology demonstration project. It is hoped that relevant departments will set up projects, provide financial support, carry out technical research in advance, promote industrialization as soon as possible, and serve faster. Major power plants. To help the country smog weather governance.