中国燃煤发电节能技术的发展及前景

我国一次能源结构决定了发电以煤电为主的基本格局,当前国内火力发电行业需要解决的两大突出问题是高能耗和严重的环境污染。2009年全国发电机组平均供电煤耗341g/(kW.h),高于330g/(kW.h)的国际平均水平。大力发展新型高效节能性火力发电技术,对进一步提高我国火力发电机组的发电效率,减少燃煤大气污染物排放具有十分重要的意义。发达国家正积极发展更高参数的超超临界火力发电技术(600℃/700℃),我国也把"超(超)临界燃煤发电技术"列入"863计划"。可以预见,在我国近中期电力事业的发展中,会把发展更高参数的超临界技术作为火电建设的主要方向。IGCC发电技术是未来煤炭能源系统的基础,被公认为是世界上最清洁的燃煤发电技术。随着煤气化技术和燃气轮机技术的不断发展和进步,IGCC将朝着大容量、高效率、低排放的方向发展。大型直接空冷发电技术是解决我国西北部富煤贫水地区火力发电的有效手段,以2×600MW机组为例,空冷机组比湿冷机组节水约80%左右。通过对火力发电机组各系统的集成与优化,可在现有超超临界机组技术不变的情况下,最大限度地利用余热回收,提高整个机组的发电效率,从而降低煤耗,实现机组在运行过程中的节能。

The Development and Prospect of Coal-Fired Power Generation Energy-Saving Technologies in China

Determined by its primary energy mix,China relies on coal to meet its electricity demand.High energy consumption and serious environmental pollution are the two major challenges the domestic coal-fired power generation industry needs to address.In 2009,power generators in China consumed an average 341g/（kW·h） of coal,higher than the international average level of 330g/（kW·h）.Developing novel,high-efficiency and energy-efficient coal-fired power generation technologies is of great significance to raising the power generation efficiency of domestic coal-fired generators as well as reducing the emissions of coal-derived air pollutants.Developed countries are actively developing ultrasupercritical（USC） coal-fired power generation technologies with higher parameters（600℃/700℃） and China has also incorporated the development of USC coal-fired power generation technologies into its 863 Plan.It is anticipated that supercritical technologies with higher parameters will become the main direction for building coal-fired power generation capacities in China＇s short-and medium-term power development plans.IGCC technology will form the base of the future coal energy system and is regarded as the world＇s cleanest coal-fired power generation technology.With the continuous development and advancement of coal gasification and gas turbine technologies,large capacity,high efficiency and low emission will be the trends of IGCC technology.Large-scale direct air-cooling power generation technology will be an effective coal-fired power generating approach for northwestern China rich in coal and poor in water.For a 2×600MW generating set,for instance,an air cooling generator requires around 80% less water than a wet-cooling generator.The overall power generating efficiency of a coal-fired power generating set can be raised by integrating and optimizing the individual systems that together form the generating set and making the best of residual heat without revamping the existing USC technology,thus reducing coal consumption and saving energy during operation of the generating set.