问题 问答题 简答题

气化温度,压力及汽氧比是如何控制的?

答案

参考答案:

气化温度是指炉内的最高温度。气化温度一般来说是越高越好,但是炉内温度受灰熔点的限制以及设备材质的限制,所以气化温度的确定一般主要由灰熔点来定。

气化压力主要是由下列几点来确定的:

①从制气的目的,用途来确定压力。

②从节省能源方向考虑,即考虑与气化相联系

的空分装置,以及后续工号所需压力的高低来确定。

③设备材质也是确定的一个方面,它只是限制

压力的选择,并不是确定压力的主要因素,即选择高压气化需要耐高压材质,所需的投资就大。另外,现有的材质限制了气化压力的过大提高。

汽氧比的确定:

控制汽氧比也就是控制气化炉的温度,一般来说气化

温度控制在接近灰熔点温度条件下操作为最佳,这与炉内吸热反应的速度有关,因此汽氧比也与煤种有关,因此,汽氧比的确定一般应由灰熔点及煤种的活性来确定。

选择题
完形填空
完形填空。
     In 1990 my husband, Donald, and I were vacationing in Hawaii. Donald and I had been there many times
over the years.
     The weather was   1   that day and we practically had the beach to ourselves. The   2   reached its top,
close to shore, and I walked   3   into the surf, waiting for a breaker. Within seconds the huge waves knocked
me off my   4  . My legs suddenly felt powerless. I thrust my arms up. "Help! Help!"
     My husband was on the beach with his   5  , ready to take a picture of me riding in on a breaker. "Donald!" I   6  , struggling to signal with my hands. He didn't   7  . He couldn't hear my cries. The few others on the
beach were too far away. 
       8   I knew that if I swam with the current (洋流) I'd stay along the   9  , I panicked and fought to get  10  
on the beach. I tried desperately to keep my head  11  water. But I couldn't get back to shore, no matter how
hard I tried.
     Extremely  12  and out of breath, I looked up. A nice-looking young man was beside me He stood solidly,
as if his feet were  13  in the ocean floor. How strong he  14  be, I thought. "Take my hand," he said, "and relax."
 15  for him and the next thing I knew I was  16  toward my husband.
     Donald held me tight, understanding at last that I had been  17 . "I'm so glad you're safe," he  18 .
     "Thanks to this young man," I said,  19  to introduce my rescuer.
     "He was here a second ago," Donald said. We looked  20 . No one was anywhere near US.
( )1. A. perfect     
( )2. A. beach       
( )3. A. anxiously   
( )4. A. head        
( )5. A. glasses     
( )6. A. sighed      
( )7. A. understand  
( )8. A. Even if     
( )9. A. sea         
( )10. A. off        
( )11. A. into       
( )12. A. disappointed
( )13. A. planted    
( )14. A. will       
( )15. A. pointed    
( )16. A. running    
( )17. A. in danger  
( )18. A. answered   
( )19. A. appearing  
( )20. A. around     
B. wild         
B. wave          
B. skillfully    
B. shoulders      
B. friends     
B. shouted       
B. worry         
B. Whenever      
B. ship           
B. over         
B. above        
B. painful      
B. reflected    
B. can         
B. asked        
B. walking       
B. in sight    
B. whispered    
B. attempting   
B. up         
C. typical       
C. wind             
C. proudly      
C. hands             
C. camera     
C. begged       
C. react         
C. Ever since      
C. wave            
C. back          
C. near           
C. tired         
C. separated    
C. must         
C. waved         
C. rushing         
C. on time     
C. screamed      
C. beginning     
C. down        
D. special     
D. sun               
D. eagerly     
D. feet               
D. umbrella
D. insisted       
D. mind           
D. Because                  
D. shore           
D. away           
D. toward         
D. puzzled       
D. stuck       
D. may          
D. reached        
D. jogging         
D. on leave   
D. laughed       
D. turning       
D. on