Zhejiang Huaneng Yuhuan Power Plant under construction is the first power plant in China to adopt domestic million kilowatt ultra-supercritical coal-fired units. The planned installed capacity of the power plant is four ultra-supercritical coal-fired units with a capacity of 654.38+100,000 kilowatts, and two units with a capacity of 654.38+100,000 kilowatts will be built in the first phase of the project, which started in June 2004 and is expected to be put into production by the end of 2007. Power experts pointed out that the advanced technology of energy saving, environmental protection and water saving in this national key project represents the development direction of coal-fired power plants in China.
More power generation ≠ More coal consumption
This is a technical term that layman can't understand-ultra-supercritical coal combustion technology. Power experts explained the advantages of this technology in the simplest terms: compared with the national average coal consumption in 2004, this coal-fired power generation technology can save about 88 grams of coal in power generation 1 kwh; According to the current installed capacity of thermal power units in China, if coal-fired power plants all over the country adopt this technology to generate electricity, more than 200 million tons of raw coal can be saved every year.
High energy consumption and unit coal-fired power generation are far behind the international advanced level, which is one of the outstanding problems of coal-fired power generation in China. Behind the lack of electricity is the lack of coal. According to statistics, in 2004, China's coal supply was about 65.438+0.98 billion tons, while the actual demand was about 26.5438+0 billion tons, of which the demand for electric coal alone increased by 65.438+0.2 billion tons over the previous year.
According to the requirement of quadrupling China's gross national product by 2020, China will add more than 300 million kilowatts of thermal power units in the next 15 years, which requires that the supply of thermal coal will be greatly increased by then. Therefore, as a kind of non-renewable energy, the supply of coal seriously limits the sustainable development of China electric power industry, which is dominated by coal-fired power plants, and it is urgent to build a number of high-efficiency coal-saving power plants.
According to Li Jianmin, project manager of Huaneng Yuhuan Power Plant, all four units in the power plant can generate 22 billion kWh of electricity every year, based on the annual power generation time of 5,500 hours. Compared with subcritical coal-fired power plants which are widely used at present, Huaneng Yuhuan Power Plant can save 400,000 tons of coal with the same power generation every year, which truly realizes the energy-saving goal that more power generation does not mean more coal consumption.
Lu Yanchang, chairman of China Electrical Engineering Society, said in an exclusive interview: "At present, coal used for power generation accounts for more than half of domestic coal production, and the shortage of coal resources has become a key factor restricting the development of coal-fired power plants. Huaneng Yuhuan Power Plant takes the lead in adopting internationally advanced ultra-supercritical coal-fired units, which represents the future development direction of China's coal-fired power plants and plays an exemplary role in coal-saving power generation in coal-fired power plants, and will certainly make China's thermal power generation look brand-new.
More power generation ≠ More pollution
Statistics in 2004 show that the ash generated by coal-fired power generation accounts for about 70% of the national ash, soot emissions account for 33% of industrial emissions, and sulfur dioxide emissions account for 56% of industrial emissions. Lu Yanchang believes that the large pollutant emission is another outstanding problem of coal-fired power generation in China. According to reports, Huaneng Yuhuan Power Plant adopts ultra-supercritical coal-fired units, which reduces the amount of coal used for power generation and the resulting pollutants. At the same time, the power plant has invested heavily in environmental protection, and has strict prevention and control countermeasures for air pollution, water pollution, solid waste gas pollution and noise pollution.
The assessment meeting hosted by the Environmental Engineering Assessment Center of the State Environmental Protection Administration believes that Huaneng Yuhuan Power Plant's million kilowatt ultra-supercritical power generation belongs to clean coal technology and is the most advanced coal-fired power generation technology in the world. After treatment, the emission concentration of sulfur dioxide, nitrogen oxides and soot in power plants is far below the national limit, and other pollution control indicators also meet the national standards, and the wastewater recovery rate even reaches 100%. Therefore, the project construction plays a positive role in stabilizing the local atmospheric environment and improving the overall level of power production in China.
Lu Yanchang told reporters that increasing the proportion of ultra-supercritical units used in coal-fired power plants in China is the most effective and realistic way to reduce pollution, which is not only a long-term solution, but also a top priority. Huaneng company has made a good start for other domestic power plants in building environmental protection power plants.
The more electricity generated, the more water used.
Coal-fired power generation needs a lot of circulating cooling water, industrial cooling water and chemical make-up water. The unit with seawater direct cooling technology uses 0. 12 tons of fresh water per second per million kilowatts. At present, China's per capita water resources are only 2,200 tons, which is about 3 1% of the world average, and it is one of the poorest countries in the world.
Huaneng Yuhuan Power Plant needs 8 million tons of fresh water every year. Yuhuan county, as a key island county with drought and water shortage in Zhejiang Province, has seven reservoirs with a full capacity of less than 20 million tons. The lack of water resources has begun to affect the sustainable development of the county, and 8 million tons of fresh water is undoubtedly a great burden.
Huaneng Yuhuan Power Plant pioneered the "double-membrane" seawater desalination process in China, and invested 200 million yuan to build a seawater desalination system with an hourly water output 1440 tons, so that all the fresh water needed by the power plant comes from seawater. At the same time, Huaneng Yuhuan Power Plant has optimized the classification and water quality of process water in the whole plant, making the reuse rate of fresh water reach over 64% and the reuse rate of waste water reach 1 0,000%, significantly reducing the consumption of fresh water resources. The water consumption of a million kilowatt power plant unit is nearly 0.09 tons per second, which is close to the international advanced level of 0.08 tons.
Lu Yanchang pointed out that China's water resources are relatively scarce, which requires "saving water and reducing consumption" as an important topic in the research of coal-fired power generation technology. While trying to improve the reuse rate of fresh water, seawater desalination technology is adopted in coastal areas and mine water treatment methods are studied in inland areas. Building water-saving power plants is of great significance to China, where water resources are increasingly scarce.
Saving coal, protecting environment and saving water make Huaneng Yuhuan Power Plant become the coal-fired power plant with the highest thermal efficiency and the highest comprehensive energy-saving and environmental protection level in China. Compared with foreign power generation technology, it can be shortened by 30 to 40 years and reach the international advanced level.