问题
问答题 简答题
为什么多效蒸发的效数有一定限度?
答案
参考答案:
蒸发器的效数越多,加热蒸汽消耗量就越小。但随着效数的增加,加热蒸气的节省率却逐渐变小,当效数增加到一定程度,节约的蒸汽费将弥补不了由于设备增加而增加的设备费。所以多效蒸发效数一般都控制在2-3效。
为什么多效蒸发的效数有一定限度?
参考答案:
蒸发器的效数越多,加热蒸汽消耗量就越小。但随着效数的增加,加热蒸气的节省率却逐渐变小,当效数增加到一定程度,节约的蒸汽费将弥补不了由于设备增加而增加的设备费。所以多效蒸发效数一般都控制在2-3效。
Millie 正和Jill 谈论她家附近的一个新公园。根据上下文,选择合适的句子将她们的对话补充完整。 | |
(M= Millie, J=Jill They're classmates.) M: Hello, Jill! 1_______ J: 2_______. Is it very big? M: No, it's not very big, 3_______. J: Well, what's in it? Are there any lakes? M: Yes, there is a lake. 4_______. J: Is there a zoo? M: No, there isn't. But there are many birds in it, and there're lots of flowers too. J: 5_______. M: There isn't a shop in the park, but there are some small shops near the park.
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