Importance of Waste-to-Energy to China and to the Global Climate
The generation and disposal of municipal solid wastes (MSW) have become a major environmental problem for at least three reasons: In the absence of intelligent waste management, greenfields are constantly -and forever -converted to cemeteries of garbage. Of more immediate and global interest is that methane generated in uncontrolled landfills is a significant contributor to greenhouse gases and the already observed climate change. The third reason is that burying a ton of material that is equivalent to a barrel of oil is clearly wasteful and non-sustainable. The generation of billions of tons of solid wastes by humanity presents both a challenge and an opportunity to developing nations like China. The information presented in this paper shows that China, more than any other developing nation, has comprehended the importance of intelligent management of human solid wastes. Since the beginning of the 21st century, China has increased its waste-to-energy (WTE) capacity from 2 to 14 million tons of municipal solid wastes. This makes China the fourth largest user of waste-to-energy (WTE), after E.U., Japan, and the U.S. There were 66 WTE plants in China by 2007 and are projected to increase to one hundred by 2012.Two thirds of these plants are based on either imported or domestic moving grate technologies; and the other third on various Chinese forms of the circulating fluid bed reactor. This paper also examines in detail the environmental performance of Chinese WTE plants. Using as a yardstick the most infamous of WTE emissions, dioxins, we found that in a sample of 19 Chinese WTE plants, seven operate below the E.U dioxin standard (0.1 nanograms TEQ per standard cubic meter of stack gas) and twelve above this standard. On the other end of the scale, the highest recorded emission was 24 times as high as the E.U. standard. The fact that several WTEs in China are able to control dioxin emissions to the very strict E.U. dioxin standard (which is ten times lower than the present Chinese standard) is very encouraging and indicates that Chinese operators and gas control systems can be as good as those in the west.
Waste management waste-to-energy WTE municipal solid waste MSW China CFB grate combustion
Nickolas J. Themelis Zhixiao Zhang
Earth Engineering Center, Columbia University Dianzi University, Hangzhou, China
国际会议
北京
英文
1173-1190
2010-05-17（万方平台首次上网日期，不代表论文的发表时间）