问题 问答题 简答题

如何判断炉况失常现象?发现炉况失常时应采取哪些处理方法?

答案

参考答案:

(1)球团矿呈暗红色,强度低、粉末多。

判断:供热不足,焙烧温度低或矿粉粒度太粗,下料过快,生球质量差。

处理方法:根据焙烧球团的热耗量,计算煤气量,为球团焙烧提供充足的热量;并根据矿石性质适当调整燃烧室温度,提高生球质量,减少生球爆裂和入炉粉末;以改善料层透气性。

(2)成品球团矿生熟混杂,强度相差悬殊。

判断:下料不均,炉内温度相差较大。

处理方法:根本办法是提高生球强度,减少粉末入炉,以改善透气性;其次改变炉料的运动状态,调整排矿齿辊运行速度及采取“坐料”等手段,以松散炉内物料,使炉料均匀下降,并检查竖炉喷火口是否堵塞。

(3)成品球温差较大。

判断:炉料产生偏析;排矿量不均,料球温度相差较大。排矿温度高而球团强度低,炉膛两侧温度明显不同。

处理方法:调整两溜槽的下料量,多开下料慢一侧的齿辊,提高下料快一端的煤气烧嘴温度(增大废气量);必要时采取坐料操作(即停止排矿一定时间后,再突然大排矿,亏料以熟料补充)。

(4)下料不匀:炉口下料不匀,局部过快,干燥速度相差较大,局部气流过大,炉膛温度变化无规律。

判断:炉内发生窜料,(形成管道)或悬料;如不及时处理,在下料快处湿球入炉,就会产生粉末,更加恶化炉况,形成堆积黏结现象,造成结大块的事故。

处理方法:往下料处补熟球,采取坐料操作,大排矿一次(排矿高度1m左右),再补熟球,以消除炉内管道,恢复炉料正常运行。

(5)燃烧室压力升高:煤气和空气量没变,而燃烧室压力突然升高,两燃烧室压差大,炉顶烘干速度减慢。

判断:湿球入炉,粉末增加,喷火口上部位产生湿堆积黏连现象。

处理方法:适当降低燃烧室温度和废气量,停止加生球,补加熟球,继续正常排矿,待这批物料下降到喷火口下,燃烧室压力正常后,再恢复正常生产。严重时可大排矿至喷火口以下,将这种轻度黏结物捅掉,重新补熟球,再行开炉。

单项选择题
完形填空
It was lunchtime and I walked into a small branch bank on the West Side. I had come to   1  a checking account. The only officer on   2  was a fortyish black man, standing   3  a small counter from a young white boy who was wearing a V-necked sweater. I thought I was especially   4  of the boy because he looked more like from a prep school than a   5  in a West Side bank.
The boy continued to   6  my attention because of what happened next. He was holding an open savings-account book and   7  an expression of disappointment. “But I don’t understand. I opened the account myself, so why can’t I   8  any money?” the boy said, his voice breaking.
“I know it is, but those are the rules. I’ve already explained to you that a fourteen-year-old is not   9  to withdraw money without a letter from his parents,” the officer explained patiently.
Suddenly I noticed the   10  had a series of small deposits (存款) and withdraws. Then I questioned the officer, “How do you   11  that? Why did you let him withdraw money before, but not now?” He looked   12 . “Because the tellers were not aware of his age before and now they are. It’s really very   13 .” I turned to the boy with a shrug. “You’re really getting   14 ,” I said. “You ought to get your parents to come here and protest.” The boy looked destroyed.   15 , he put his savings book in a rear-pocket and walked out of the bank.
The officer turned to me. “You know,” he said, “you really shouldn’t have got   16 .” I couldn’t believe what he was saying. “We were   17  this morning that some neighborhood bully has been shaking down (敲诈) this boy for more than a month. The guy was   18  him to take money out every week and hand it over. The poor kid was   19  too scared to tell anyone. Anyway, the police are on the case and they’ll probably make a(n)   20  today.”
“You mean there is no rule about being too young to withdraw money from a savings account?”
“Not that I ever heard of. Now, sir, what can we do for you?”
小题1:
A.makeB.openC.buyD.choose
小题2:
A.dutyB.boardC.displayD.business
小题3:
A.onB.afterC.overD.across
小题4:
A.sureB.proudC.awareD.afraid
小题5:
A.guardB.customerC.clerkD.manager
小题6:
A.attractB.payC.attachD.control
小题7:
A.achievingB.findingC.reachingD.wearing
小题8:
A.useB.spendC.withdrawD.bank
小题9:
A.supportedB.inspiredC.encouragedD.allowed
小题10:
A.letterB.accountC.noteD.message
小题11:
A.thinkB.explainC.doD.claim
小题12:
A.annoyedB.disappointedC.confused D.amused
小题13:
A.difficultB.strangeC.fantasticD.simple
小题14:
A.obeyedB.stolenC.cheatedD.caught
小题15:
A.HappilyB.SilentlyC.CheerfullyD.Nervously
小题16:
A.interactedB.interruptedC.involvedD.infected
小题17:
A.occupied B.discoveredC.suggestedD.informed
小题18:
A.rushingB.forcingC.requestingD.begging
小题19:
A.hardlyB.unwillinglyC.apparentlyD.eagerly
小题20:
A.arrestB.sentenceC.apologyD.difference