问题 问答题 简答题

低压空分临时停车时,如何恢复生产?

答案

参考答案:

⑴外线改为大罐直接送气,保证氮气的连续供应,然后停止氮压机运行。

⑵启动汽化器、打开蒸汽加热阀和液氮贮罐出口阀,给氮压机供气。

⑶启动8#、9#、10#机往外供气,停止大罐供气。在氮气量不够时,可停止10#机运行,用大罐高压或低压管线送气,注意控制用量。

⑷在外线送气的同时,停止透平膨胀机的运行,打开出口放空阀,关闭分馏塔氧、氮产品送出阀。

⑸停冰机,冷冻水泵,冷却水泵和空压机(若空压机未发生故障,可不停空压机,只需降低出口设定压力,压缩空气改放空即可。

⑹停纯化器,将程序调在“暂停”位置,使现场阀门开关状态保持原状。

⑺迅速查明原因,联系有关人员处理故障,同时向车间及调度汇报,各岗位做好重新开工的准备工作,待故障消除后,马上进行开工操作。

⑻重新开工时,首先启动空压机(若空压机未停,则直接按正常操作步骤逐步提高出口设定值,直到出口压力达到550MPA.。再启动冷却水泵冷冻水泵和冰机,纯化器取消“暂停”走程序控制。

⑼打开塔出口跨线阀(V-553),为了龠下塔压力尽快上升。可关闭液空,液氮调节阀(LCV-501,HV-502),待下塔压力升至420kPa时,打开塔出口阀(HV-551)。

⑽启动透平机膨胀机,将膨胀量调至最大,尽快将液氧液面提上来,全开液氮调节阀,适当打开液空调节阀,根据正常开工步骤调节各阀开度,尽快拿出合格产品。

⑾待氧、氮合格后,打开氧、氮气送出阀,将氧、氮气出口压力改为自动控制(压力控制在正常指标内),并保证适当的流量。

⑿启动氮压机,给各装置送气。

⒀关闭液氮贮槽出口阀,停止用大罐送气,关闭汽化器蒸汽进口阀(冬季应适当打开蒸汽加热阀,在汽化器停用时,保持水温在30℃。

⒁启动高压氮压机尽快将空氮气大罐压满。氧压机可根据实际情况决定是否启动充瓶。

⒂保持膨胀机最大产冷量,尽快将液氮贮槽充满,然后降低产冷量,保持正常生产所需即可。

阅读理解

根据对话情景和内容,从对话后的选项中选出能入空白处的最佳选项。选项中有两项为多余选项。

E

We’ve all got a lot going on in our lives. Some things are fun, some aren’t. I think I’ m a fairly positive person. 1   In fact, being positive means different things to different people. 2  

Focus on what you have not what you don’t. It’s impossible for one to have all the nice things in the world. Focus on what you already have. This can create feelings of happiness.

3  If you can express thanks for everything you have, you leave little room for bad thoughts. It’s a great practice. When you focus on what really matters, so many worries go away.

Forget the past and don’t cling to(紧紧抓住) the future:  4  If you cannot forget mistakes and missed opportunities from the past, you probably find you blame yourself all the time. Clinging to the future is a bad one, too. It truly may never happen. So pay more attention to the present .

 5  It always makes me wonder what people are saying about me if they speak so ill of someone else when they aren’t around. If you don’t do this, you never have to worry about what you’ve said getting back to someone.  

A. Be grateful.

B.Here are a few key ways to being positive that have really helped me.

C.Speak about others as if they were in front of you.

D.The past will never come again.E.Being positive doesn’t mean smiling a fake smile all the time.

F.The past has happened and the future may never come.

G.Have fun and hug yourself.

判断题