化工原理(下册)期末试题样卷及答案 联系客服

发布时间 : 星期二 文章化工原理(下册)期末试题样卷及答案更新完毕开始阅读f1af32b577232f60dccca1ae

0yA/xA0yA0/xA00.54/0.1???00???10.5600yB/xB(1?yA)/(1?xA)(1?0.54)/(1?0.1)也可??yA/xAyA/xA??10.56yB/xB(1?yA?yS)/(1?xA?xS)

(2)设FS线与平衡线左交点为M?,过M?作水平线M?E?,则M?E?即为S用量最少

o时的连结线。连结SE?并延长至AB边上,得yA=0. 6(虚线位置)

四、干燥计算题(15分,每小题5分)

1.求绝干空气量V(考察X与w之间的关系)

GC =G2 (1-w2 )=G2 /(1+X2 )=237/(1+0.01)=234.7Kg绝干料/h W=GC (X1 -X2 )=234.7(0.15-0.01)=32.9Kg/h V=W/(H2-H1)=32.9/(0.023-0.0073)=2096Kg绝干气/h 2.求风机流量L

vH=(2.83×10-3+4.56×10-3Ho)×(to+273) =(2.83×10-3+4.56×10-3×0.0073)×(15+273)

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=0.825m湿空气/Kg绝干气

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L=V×vH =0.825×2096=1729.2m/h=0.480 m/S 3.求预热器加入热量QP

QP = V(I1 -I0 )=2096(109-35) =155104KJ/h=43.08KW

五、吸收计算题(15分/9、6)

(1) 属低浓气体吸收 ,x2=0

Ly1?y20.05?0.02???0.306Gx0.098?01

1/A?m?0.5?1.63;A?0.612

LG0.306NOG?

???mG?y1?mx2mG?1ln??1????mG??L?y2?mx2L?1?L

(2) L增大一倍时,因吸收过程为气膜控制,故Kya不变,HOG不变,所以NOG也不变。

1mG1.63???0.815;A?1.224,则 A?2L210.05??ln??1?1.63??1.63??4.61?1.63?0.02? 5

4.6?

??1?y1?ln??1??1??1???A??A??y21?A?

??10.05?ln??1?0.815??0.815??1?0.815?ya?1? ?y2?0.00606?L增大一倍后,溶质A被吸收的量=G?y1?y2?

而原状况下溶质A被吸收的量=G?y1?y2?

??y1?y2?0.05?0.00606G?y1?y2????1.46(倍)??Gy?yy?y0.05?0.021212

六、精馏计算题(20分/6、6、6、2) (1)

Dx0.9D?D??0.90FxF1000?0.5 ?D?500kmol/h

1000?D?W ?W?500kmol/h

1000?0.5?D?0.9?WxW

(2)泡点进料,xe?xF?0.5

?xe2.5?0.5ye???0.7141????1?xe1?1.5?0.5Rmin?xD?ye0.9?0.714??0.869ye?xe0.714?0.5?xW?0.1

R?1.5?Rmin?1.5?0.869?1.304

精馏段操作线方程:

xR1.3040.9yn?1?xn?D?xn??0.566xn?0.390R?1R?12.3042.304

(3)精馏段操作线与q线交点d坐标为:xd?xF?0.5,yd?0.566xd?0.390?0.673

ym?1?xWy?xW?dxd?xW 故提馏段操作线方程为:xm?xW 6

ym?1?0.10.673?0.1?xm?0.10.5?0.1y?1.4325x?0.04325即

m?1m或者V?(R?1)D?2.304?500?1152

L?RD?qF?1.304?500?1000?1652则可得提溜段方程y?1.434x?0.0434(4) xD 不能达到分离要求。

此题可图解说明

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