请简要叙述DMTO工艺所采用的循环流化反应方式具有那些工艺特点？
参考答案：
DMTO工艺采用的循环流化反应方式具有的工艺特点是：
1）可以实现催化剂的连续反应－再生过程；
2）有利于反应热的及时导出，很好地解决反应床层温度分布均匀性的问题；工业性试验的实践证明，在流化床反应器的密相区内，反应温度梯度可以控制在1℃之内；
3）合适地控制反应条件和再生条件，可以方便地实现反应体系的自热平衡；
4）可以实现较大的反应空速，缩小反应器体积；
5）合适地设定物料线速度，可以有效控制反应接触；
6）反应原料可以是粗甲醇或精甲醇；
7）DMTO的反应温度为400-550℃，再生温度为550-650℃，对反应、再生设备材质要求适中。
In English the weather is changable. It is a ___1____ subject of conversation. “ Isn’t it a nice day?” “Do you think it will rain?” “I think it’s going to snow. ” People often ___2____ a conversation ___3_____ these words(话). Many people think they can tell what the weather is going to be like, but they hardly (几乎不) ever agree with each other. ____4___ may say,“Do you see ____5____ in the east ? It’s going to rain tomorrow . ” Another man will say,“No . It’s going to be fine . ” People often ____6___ the weather they want. When a farmer needs water , he looks for something to tell him. “ It’s going to rain. ” He won’t believe (相信) anything else. When friends have a picnic (举行野餐) , they hope the weather is going to be fine and they can ____7___ under the blue sky . Almost (几乎) everyone ____8____ what the weather (气象预报员) will say. But he doesn’t always __9___ us what we want , and sometimes he makes mistakes (犯错误) . Still he usually _10_ closer to being correct (正确) than anyone else.
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