In order to completely win the battle in the prevention and control of air pollution, Xuzhou is determined to require all coal-fired power generation companies to carry out the transformation of the fume emissions system as soon as possible on the basis of ultra-low emissions specified by all power enterprises. In late September, Xuzhou CR completed the commissioning of the whitening project (Phase III) and realized the high-standard slurry condensation whitening technology on its two million units, thus becoming the first power company to realize it in China.
For decades, chimneys, with long white smoke plume, have been a symbol of power plants in China. In September this year, the newly-completed CR Power Million-level Unit Whitening Project (Phase III) will change the history.
It is learned that China's large-scale power plants had already achieved ultra-low emissions before this. However, the fume emissions whitening project is to further reduce the temperature, moisture content and materials carried on the basis of ultra-low emission.
With a total investment of RMB 112 million, Xuzhou CR Power's fume dehumidifying and whitening project is fully underway. After Phase III of the project, for the fume emissions standard for the 240-meter-high chimneys of the 2MW units, the smoke temperature is set to be below 47℃ after condensation in summer and the moisture content below 10.4%. And after condensation in winter, the smoke temperature can reach below 45℃, and the moisture content of the fume below 9.5%.
Due to the adoption of energy-saving technology, the fume whitening technology of Xuzhou CR Power implemented through slurry condensation has reached international advanced level.
Currently, having successfully achieved its expected goal, the slurry condensation project of the MW units has been put into trial operation.
“The large screen shows that the real-time data of enterprise fume and dust emission is less than 2mg while the national fume and dust emission is 10 mg/m3. Through ultra-low emission modification and whitening modification, the smoke and dust emission concentration will be further lowered,” said Zhang Feng, technical director of Xuzhou (Tongshan) CR Power Co., Ltd., in the Central Control Office of Xuzhou CR Power Co., Ltd.
The data will be optimized once again and far beyond the national standards after the fume emissions whitening project is completely put into operation.
Yang Qing, vice director of the Technical Support Department of Xuzhou (Tongshan) CR Power Co., Ltd., said that through the dehumidification and whitening transformation, each unit can reduce dust emission by about 20 tons per year, soluble salts by about 1000 tons, and sulfur dioxide emission by about 200 tons.
It is learned that Xuzhou CR Power, with six units with a total installed capacity of 3,280MW, is the largest thermal power plant in North Jiangsu. In order to serve Xuzhou's social development, Xuzhou CR Power quickly set up a leading group for dehumidification and whitening of flue gas. On the basis of a scientific plan made at the end of April this year, the project of dehumidification and whitening of flue gas of Xuzhou CR Power with a total investment of RMB 112 million was officially launched on May 27. Currently, Phase III of the project for the 2 MW units has been completed, while Phase I and II of the project will also be completed and put into production in late October.
Besides Xuzhou CR Power, 10 thermal power plants, including Xuzhou Power Plant of Guohua Electric Power Company, Huamei Power Plant and Xukuang Power Plant of Xuzhou Coal Mining Group, have implemented the dehumidifying and whitening project to achieve a reduction of 50% on the basis of the current ultra-low emissions.
So what exactly is the fume emissions whitening project?
According to Li Duosong, associate professor at the School of Environmental Testing, China University of Mining and Technology, white is not equal to green. White smoke contains a large amount of water vapor and carries a lot of pollutants which will aggravate atmospheric environmental pollution, especially in some local areas. Therefore, in order to completely solve the problem of coal-fired pollution in power plants, it is necessary to remove the water from the fume.
It is reported that the fume emissions by the power plants in China have been ultra-low as its emission standards are even higher than those of developed countries. Then under what context was the said project launched? According to experts, this is closely related to the current background of air pollution prevention and control carried out on a nationwide scale.
“Although our coal-fired power plants have been very strict in emissions (even lower than developed countries such as the United States and the European Union), due to the large number of coal-fired units and the high amount of fume emitted in our country, coupled with the pollutants carried by water vapor, the small particles, soluble salts, sulfuric acid trioxide mist, desulfurization absorbent, gypsum and other pollutants emitted by the fume with water will aggravate the air pollution in local areas,” said Li Duosong.
In the previous autumns and winters, Xuzhou's air quality in winter was relatively poor due to various factors such as its heavy industrial structure and backward production capacity, as well as unfavorable conditions for atmospheric diffusion.
In 2018, the city's atmospheric target is 60 micrograms per cubic meter in terms of PM 2.5 and 60% or higher in terms of fine weather. This year, having made a firm determination, Xuzhou has launched an all-round battle to prevent and control air pollution. The city has conducted a comprehensive investigation of enterprises failing to conform to the relevant standards, paid close attention to coal-fired pollution control, vigorously promoted classified rectification of coal-fired boilers, focused on special inspection of VOCs pollution control, attached great importance to dust pollution control, formulated regulations for various construction sites, harbors and ports, dismantled seriously-polluted port enterprises, and closed down illegal quarrying (gravel) sites. More than 10 power plants have reformed their fume emissions systems and basically eliminated gypsum rain and colored smoke plume, thus making their due contributions to improving the city's atmospheric and environmental quality.