随着工业的高速发展,世界各国都存在着对能源需要量不断增长的问题。2000年世界对燃料和一次能源的需要量大约是1975年的2.5倍(图1),应量指出,世界各国对能源的需要量是不一样的。随着工艺过程的改善,能耗在不断降低。例如:在中世纪冶炼一吨钢要消耗100～150吨当量石油,1吨当量石油等于1600 With the rapid development of industry, all countries in the world have the problem of growing energy demand. In 2000, the world’s demand for fuel and primary energy was about 2.5 times that of 1975 (Figure 1). It should be pointed out that the world needs different amounts of energy. With the improvement of the process, energy consumption continues to decrease. For example, smelting a ton of steel in the Middle Ages consumes 100-150 tons of equivalent petroleum, and 1 tonne of equivalent oil equals 1600