The furnace can alternatively be supplied with a back exhaust when waste gas contact on chargematerial must be avoided.
当必须避免废气与装料接触时，这种炉子需更换一个后式烟囱。
2
The combination of increasing chargematerial temperature with overall energy saving has become an important objective, which has only in recent years begun to be achieved.
如何将提高装料温度与综合节能结合起来已成为一个重要课题，而仅在最近几年这一目标才刚刚实现。
3
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