化工原理课程设计
§3.2液泛验算
降液管内泡沫液层高度可按下式计算:Hd?hp?hw?how???hd?hp?hL?hd 浮阀塔德液面落差不大,常可忽略不计 (1)精馏
2段
hp?0.0655m,hL?0.05m2塔板上不设进口堰时:
?LS??1.38?10?3?hd?0.153???0.153????0.000899m
lh0.72?0.025???w0?Hd?0.0655?0.05?0.000899?0.1164m
取??0.5,??HT?hw??0.50.5(0.35+0.03995)=0.195,Hd?m??0.35?0.03995??0.194975??HT?hw? (2)提馏段hp?0.0655m,hL?0.05m
?L's??2.71?10?3?'塔板上不设进口堰时:hd?0.153???0.153????0.00346m
?0.72?0.025??lwh0?Hd?0.0608?0.05?0.00346?0.1143m
''220.5??0.03960.49??0.0.1948245,Hmd???HT?hw? 取??0.5,??HT?hw??0.5
§3.3 雾沫夹带验算
泛点百分率可取下列两式计算,取计算结果中较大的数值:
VsF??V?L??V?1.36LsZs,F?Vs?V?L??V,ZL?D?2Wd,Ab?AT?2Af
KCFAb0.78KCFAT(1) 精馏段:
1.382?F?1.3509787.5994?1.3509?1.36?1.38?10?3??1.2?2?0.138??0.65
1?0.094??1.13?2?0.06215?1.32802.365?1.32?0.691?0.7
1.382?F?0.78?0.6359?1?0.098(2)提馏段:
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化工原理课程设计
1.35?F?0.9375892.2846?0.9375?1.36?2.71?10?3??1.2?2?0.138??0.51
1?0.092??1.13?2?0.06215?0.9375892.2846?0.9375?0.54?0.8
1.35?F?0.78?1.13?1?0.092
§3.4 操作性能负荷图
3.4.1.气相负荷下限图(漏液线)
?45(1)精馏段:Vs?d0N2?V5??4?0.039?123?251.3825?0.625m/s
3(2)提馏段:Vs??4d0N2?V??4?0.039?100?20.9375?0.616m/s
33.4.2.过量液沫夹带线
取F?0.8
Vs?1.382787.5994?1.382?1.36Ls??1.2?2?0.138?(1) 精馏段:0.8?1?0.092??1.13?2?0.0625?
得Vs?1.766?29.99Ls
'Vs?0.9375892.2846?0.9375?1.36Ls??1.2?2?0.138?'(2) 提馏段:0.8?1?0.092??1.13?2?0.0625?
''得Vs??38.75Ls?2.282
3.4.3.液相负荷下限线
22?3600LS?E?(1)精馏段:0.006??1000?Lw?2.84
3?3600LS???1.027???1000?0.72?2.8426
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化工原理课程设计
得:LS?0.000589m3/s
?3600L?E?(2)提馏段:0.006??1000?lw?2.84's23?3600L???1.038???10000.54??2.84's23
得:LS?0.000581m3/s
3.4.4.液相负荷上限线
LS?AfHT5?0.06215?0.355?0.00435m/s
3.4.5.液泛线
2液泛线方程:aVs?b?cL?dLs3 (1) 精馏段:
a?1.91?10?522s?v?LN2?1.91?10?51.3509787.5994?1232?0.0217
b??HT????1??0?hw?0.5?0.35??0.5?1?0.5??0.03995?0.13505
c?0.153lh2w20?0.1530.72?0.02522?472.22
d??1??0?E?0.667?1lw32??1?0.5??1.027?0.667?10.7223?0.825
0.0217V2S?0.13505?472.221L?0.825Ls3
2s2(2) 提馏段:
a?1.91?10?'5?v?N'L2'?1.91?10?50.9375892.2846?1002?0.0201
b??HT????1??0?hw?0.5?0.35??0.5?1?0.5??0.0396?0.1354
''c?'0.153Lh2w20?0.1530.72?0.03322?270.2d??1??0?E?0.667?'1lw32??1?0.5??1.038?0.667?10.7223?1.293
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化工原理课程设计
0.0201VS?0.1354?270.2Ls?1.293Ls3
222操作性能负荷图
(1) 精馏段:
由图可知,该塔的操作上限为过量液沫夹带控制,下限为漏液控制。由图可读得:
?Vs?max?1.451m/s,?Vs?min?0.364m/s
33?Vs?max所以,塔的操作弹性为
?Vs?min(2)提馏段:
?1.4510.364?3.986?2
由图可知,该塔德操作上限为雾沫夹带控制,下限为漏液控制。由图可读得:
?Vs?max
?1.834m/s,?Vs?min?0.433m/s
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化工原理课程设计
?Vs?max所以,塔德操作弹性为
?Vs?min
?1.8340.433?4.24?2
4、阀塔工艺设计结果
项目 塔径D/m 板间距HT/m 板上液层高度hL/m 空塔气速 精馏塔u/(m.s?1) 提馏塔u/(m.s?1) 溢流堰长度lw/m 溢流堰高度 精馏段hw/m 提馏段hw/m 降液管截面积Af/m 降液管高度Wd/m 降液管底隙高度 精馏段h0/m 提馏段h0/m 数值 1.2 0.35 0.05 1.223 1.195 0.72 0.0393 0.0332 0.06215 0.138 0.0025 0.033
浮阀数N/个(等边三角形叉排) 开孔率% 实际动能因数F0 精馏段 提馏段 精馏段u0/(m.s?1) 阀孔气速 提馏段u0/(m.s?1) 孔阀中心距t/m 塔板压降
74 13 10.83 13.00 9.3145 11.19 0.075 0.0655 精馏段hp/m 29