合成氨工段全算

1、合成氨全算1.2m合成流程简图1=11-氨冷器2-冷交3-循环机4-合成塔5-热交6-废热锅炉7-软水预热器8-水冷器9-氨分10-液氨储罐合成氨物料衡算一已知条件及设计条件1、合成原料气体（精炼来气）成分（氢氮比3）成分H2N2ch4Ar合计百分含量73.5%24.5%1.5%0.5%100%2、合成甲烷控制14.5%3、进塔氨含量2.5%，出塔氨含量13.2%4、催化剂填装量11.24 M35、水冷器的出口气体温度35 C6、1.2m合成系统设计生产负荷15t/h7、系统工作压力31.4Mpa8、计算标准1tNH3衡算数据查询有限，有的时候采用了资料上现成的数据，没有符合当前的系统状态。二

2、计算1、合成进塔气体成分CH4N2H2Arnh30.1450.2250.5950.010.025注：甲烷为操作值，氢为表测值，氨为实验值，氩为假设值，氮气为反推值，在这个气体成 分下，氢氮比为2.6为合理值。2、合成塔出口气体成分假设合成塔的进口气体量为A mol,则有出塔氨量为A*(13.2%-2.5%)1 +13.2%=0.09452A mol除去氨外出塔的气体量为A-0.09452A=0.90547AmolyNH3=13.2%yCH4=0.145A/0.90547A=0.1601=16.01%0.225A - (0.0945A *0.5) yd=0.90547 A=19.63%0.595

3、A - (0.0945A *1.5) yH2=0.90547 A=50.05%CH4N2H2Arnh30.16010.19630.50050.0110.132yAr=0.01A/0.90547A=1.10%塔出口气体成分表：3、合成率合成率0.09452A * 2A *(1 0.145 0.01 0.025)=23.05%4、氨分出口气体成分分离下有物料总衡算式F总=V气+L液两相平衡有K(i)= 空，是组分食是液相中分比?是气相中的分比K(i)为组分i的相平 x(i)衡常数(四)K (i) =(知)1 LF (i) Lx(i)VLX(i)L(F (i)Lx(i)1)推出旦) 1 = (-)K

4、(i)Lx(i)L,、F (i),、公式变形 Lx(i) = -= L(i)(了) K (i) +1L = L(i).气态组分x(i)=L(i)F (i) - L(i)V假定氨分进料量为A mol氨分入口气体成分为叫N2H2Arnh30.16010.19630.50050.0110.132在35C, 29Mpa时有相平衡常数表Kch 4Kn2Kh 2KaKnh38.20034.527.528.20.098假设 V/L=21.36T . F (i)Li =1 + (V/L) K (i)LNH3=0.04267315A molLCH4=0.000913983A molLAr=1.82315E-05

5、A molLH2=0.000850612A molLN2=0.000266018A mol液相总和 L=0.044721994A； V=A-L新的 V/L=21.36036244V/L误差=-1.69684E-05，验证气液比正确液相中各成分含量为xNH3=LNH3/L=0.95418709=95.42%xCH4=0.020437=2.04%xAr=0.000407663=0.04%xH2=0.019019989=1.901%xN2=0.005948259=0.059%气相中的各成分含量yNH3=VNH3/V=9.351%yCH4=16.758%yAr=1.150%yH2=52.304%yN2

6、=20.521%液相中的氨含量95.419%气相中的氨含量9.351%液相中的甲烷2.044%气相中的甲烷16.758%液相中的氩0.041%气相中的氩1.150%液相中的氢1.902%气相中的氢52.304%液相中的氮0.595%气相中的氮20.521%5、冷交出液相成分引用数据，此数据我没有查（-10C, 28Mpa相平衡常数）Kch4Kn Kh 2KaKnh32728075510.0254合成塔入塔气体成分CH4N2H2Arnh30.1450.2250.5950.010.025x(i)=y(i)/K(i)由合成塔入塔气体成分可得xCH4xN2xH2xArxNH30.537%0.281%0

7、.793%0.020%98.425%6、球罐出口气相与液相成分氨分和冷交共同放氨，进入球罐则氨分分离的氨G%=(1云进塔氨)*界出塔氨含量氨分出口氨含量七(y出塔氨含量-y进塔氨含量)* (1 - y氨分出口氨含量)y为气相G%=40.676%即氨分的分离量为40.676%，冷交分离量为59.324%进入球罐的混合物的成分为W(i)=0.406氨分液相(i)+0.593冷交液相(i) i为成分可根据各公式求得混合之后的液相的成分为Xch4 Xn2 Xh2 XaT Xnh30.0114988760.0040880.0124429440.0002820.972023假定进料量为Amol球罐温度为1

8、7摄氏度，压力为1.5Mpa时的各成分的相平衡常数是KCH4Kn2Kh2KArKNH31706205755400.598F(i)1 + （V/L）K（i）设球罐的气液比为V/L=0.071LNH3= 0.932433729A molLch4= 0.000879792A molLAr= 7.16828E-06A molLh2= 0.0002975A molLn2= 9.08041E-05A mol液相总和 L=0.044721994A； V=A-L新的 V/L=0.070997503V/L误差二0.00352%，验证气液比正确液相中各成分含量为xNH3=LNH3/L=99.863%xCH4=0.

9、094%xAr=0.001%xH2=0.032%xN2=0.010%气相（驰放气）中的各成分含量yNH3=VNH3/V=59.720%yCH4=16.019%液相中的氨含量99.863%液相中的甲烷0.094%液相中的氩0.001%液相中的氢0.032%液相中的氮0.010%yAr=0.415%yH2=i8.321%yN2=6.030%气相中的氨含量59.720%气相中的甲烷16.019%气相中的氩0.415%气相中的氢18.321%气相中的氮6.030%7、球罐物料衡算以1tNH3为标准计算转换为气态标准体积有球罐中液相成分为液相中的氨含量99.863%液相中的甲烷0.094%液相中的氩0.

10、001%液相中的氢0.032%液相中的氮0.010%1tNH3 存在的必要体积=1000/(17/22.4)/99.863%=1319.449NM3吨氨中的各成分体积为在必要体积中的百分占有量即必要体积乘以百分比吨氨中的成分单位NM3NH31317.647059CH41.243257035Ar0.010129683H20.420405432N20.128317686球罐中气液比为V/L=0.071驰放气量=0.071*1319.449二 93.68089驰放气中成分单位NM3NH355.9466263CH415.00664015Ar0.388385723H217.16365537N25.648

11、74318总体积=吨氨各成分+驰放气各成分=1413.603219NM3反向核算个成分百分比=(吨氨中i成分量+驰放气中i成分量)/总体积NH3%=(1317.647059+55.9466263)/ 1413.603219=0.971696772 同理其他成分有表各入口成分核算百分比NH30.971696772CH40.011495374Ar0.000281915H20.012439177进入球罐液体成分xCH4xN2xH2xArxNH3百分比0.0114990.0040880.0124430.0002820.972023N20.004086763两表比较有各成分比例大概相同。核算结果为入口成

12、分计算准确。8、合成系统物料衡算新鲜气1入塔气体2出塔气体3驰放气4放空气5球罐中氨6NH300.0250.1320.597200.093510.99863CH40.0150.1450.1610.160190.167580.00094Ar0.0050.010.0110.004150.011500.00001H20.7350.5950.50050.183210.523040.00032N20.2450.2250.19630.060300.205210.00010以下的代表的都是相对应的成分含量值氢VyH=VyH+ V5yH2 +3 V4yNH3 + 3 V5yNH3 +3 V6yNH3 TOC

13、o 1-5 h z 1-24-2-222（2）氮-1 ,- 1 -1 ,-VyN=VyN+ V5yN2 +_ V4yNH3 + _ V5yNH3 +_ V6yNH31242222甲烷+氩V1（yCH4+yAr）=V4（yCH4+yAr）+ V5（yCH4+yAr）氨V3yNH3-V2yNH3=V4yNH3+V5yNH3+V6yNH3（5）总物料V2=V3+V1-V4-V5-V6yNH3已知 V4= 93.68089NM3 V6= 1319.449NM3联立（1）（2）（3）得 V1= 2819NM3 V5= 228NM3V1，V2 带入（4）（5）联立得 V2= 11852NM3 V3= 10

14、532NM38、合成塔进出口物料合成塔进口物料NM3NH3296.3CH41718.54Ar118.52H27051.94N22666.7合成塔出口物料NM3NH31390.224CH41695.652Ar115.852H2N25271.2662067.4329、锅炉，热交预热器都是换热，未发生液化的设备，进出口物料为合成塔出口 物料合成塔出口物料NH31390.224CH41695.652Ar115.852H25271.266N22067.432总1053210、水冷器物料水冷器进口物料水冷器进口物料NH31390.224CH41695.652Ar115.852H25271.266N2206

15、7.432总10532在氨分计算是得出的气液比为V/L=21.36则有方程V出口 = 21.36L出口V出口 + L出口 = V进总水冷器出口气相V10060.98水冷器出口液相L471.0196785气相组分物料量液相物料量NH39.351%940.7896449.434355CH416.758%1686.0259.627406354Ar1.150%115.65990.19210542H252.304%5262.3038.962805548N220.521%2064.6282.8033343811、氨分物料氨分进口物料量=水冷器出口物料，且成分一致气相组分气相物料量液相物料量NH39.351

16、%940.7896449.434355CH416.758%1686.0259.627406354Ar1.150%115.65990.19210542H252.304%5262.3038.962805548N220.521%2064.6282.80333438合10060.98471.0196785进口物料总量=V水冷器出+L水冷器出= 10532NM3氨分出口气相和液相是水冷器后分离开的，固然组成和水冷器的时候一致氨分还有一部分用去调节系统气体成分的放空气V放空气=228NM3成分表为氨分出口放空 气组分物料量NM3NH30.09350874821.31999458CH40.167580553

17、38.20836612Ar0.0114958882.621062358H20.523040817119.2533062N20.20521144746.78820995合22812、冷交二入二出物料衡算冷交二入的物料总量为氨分出口气相减去放空气的量 冷交二入物料量=10060.98-228NM3=9832.98NM3冷交二入成分物料量NM3NH30.093508748919.4696505CH40.1675805531647.816228Ar0.011495888113.0388322H20.5230408175143.049888N20.2052114472017.840056合9832.98

18、冷交而出工况：出口温度15摄氏度，压力28Mpa,查表有此时的平衡氨含量为5.9%，过饱和度为1.1则为6.5%假设二出的氨量为A NM3A/(9832.98-919.469+A)=0.0649得到 A=618.645NM3气体从二入到二出的过程中冷凝的氨=919.46-618.645=300.82NM3冷交二出气相物料量NM3气相组分液相物料量NM3NH3618.64508330.064844842300.8245672CH41647.8162280.1727200050Ar113.03883220.011848450H25143.0498880.5390817190N22017.84005

19、60.2115049840合9540.3900871300.824567213、氨冷器物料衡算进入氨冷器的物料气相量为冷交二出气体和补入新鲜气液相为冷交二出液相量进氨冷器物料表氨冷器进口成分气相物料量NM3气相组分液相物料量NM3NH3618.64508330.064844842300.8245672CH41647.8162280.1727200050来源冷Ar113.03883220.011848450交二出H25143.0498880.5390817190N22017.8400560.2115049840合9540.3900871300.8245672NH3000CH442.2850.01

20、50来源补Ar14.0950.0050入气体H22071.9650.7350N2690.6550.2450合281910NH3618.64508330.050054661300.8245672CH41690.1012280.1367463290己Ar127.13383220.0102864160总、计H27215.0148880.5837678750N22708.4950560.2191447180合12359.390091300.8245672氢氮比二0.583767/0.219144=2.6638氨冷器进口物料总量二12359.39+300.8245=12660.21NM3出口气体中气态氨

21、含量为2.5%假设氨冷器出口氨量为A NM3则有A/(12359-618.645)=0.025有 A=293.53有氨冷器出口物料表氨冷器出口气相物料NM3组分液相物料NM3NH3293.53036580.024391196625.9392846CH41690.1012280.1404406310Ar127.13383220.0105643110H27215.0148880.599538790N22708.4950560.2250650720合12034.275371625.9392846氨冷器出口氨含量为2.439%出口物料总量二12034.27+625.939=12660.21NM314、

22、冷交一入一出物料衡算冷交一入物料为氨冷器出口物料量冷交一入气相物料NM3组分液相物料NM3NH3293.53036580.024391196625.9392846CH41690.1012280.1404406310Ar127.13383220.0105643110H27215.0148880.599538790N22708.4950560.2250650720合12034.275371625.9392846进入冷交之后，有部分的氨在冷交内冷凝留在液相中 冷交一出一入冷交放氨平衡方程L出+V出二一入总量 注：l为冷交内液相，V为冷交一出气相L出yNH3+V出xNH3二入总量乘以氨含量冷交二出的总

23、氨量=293.53+625.93=919.47NM3冷交一入总物料=12340.27+625.939=12660.21NM3冷交一入氨含量=919.47/12660.21=0.07262一出物料表冷交一出气相%NM3/tNH3NM3/hKmol/hNH3 0.025285.1394277.085190.9413CH4 0.1451653.80624807.091107.46Ar 0.01114.05561710.83476.37652H2 0.5956786.308101794.64544.403N2 0.2252566.25138493.761718.472合11405.5615、球罐物料衡

24、算核算氨产171083.47637.652驰放气中的氨为93.68*0.5972=55.94球罐中氨为1009.569702NM3氨分至球罐液相物料NM3冷交至球罐液相物料NM3471.0200067625.9392846氨分出组分物料量NM3NH30.954172537449.434355CH40.0204394859.62740635Ar0.000407850.19210542H20.0190285038.96280555N20.0059516252.80333438合1471.020007冷交出组分物料量NM3NH30.984251969616.081973CH40.005370373.

25、36152579Ar0.0001960780.12273319H20.0079333334.96578499N20.00281251.76045424合1625.939285总氨量16、物料衡算汇总表1065.516328女右计山 I /口乂 LU /口%NM3/tNH3NM3/hKmol/h.%NM3/tNH3NM3/hKmol/hNH30.02439293.530374402.95549196.56051 .NH30.02500285.139004277.08498190.94129CH40.140441690.1012325351.518411131.76421 .CH40.145001

26、653.8061924807.092891107.45950Ar0.01056127.133831907.0074885.13426 .Ar0.01000114.055601710.8339976.37652H20.599547215.01489108225.223324831.48318 .H20.595006786.30817101794.622574544.40279N20.225072708.4950640627.425841813.72437 I.N20.225002566.2509938493.764841718.47164合1.0000012034.27537180514.130

27、548058.66654 .k11405.55995171083.399287637.65175合成塔一入合成塔二出%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.02500296.300004444.50000198.41518 .NH30.132001390.2240020853.36000930.95357CH40.145001718.5400025778.100001150.80804 .CH40.161001695.6520025434.780001135.48125Ar0.01000118.520001777.8000079.36607 .

28、Ar0.01100115.852001737.7800077.57946H20.595007051.94000105779.100004722.28125 I.H20.500505271.2660079068.990003529.86563N20.225002666.7000040000.500001785.73661 I.N20.196302067.4316031011.474001384.44080合1.0000011852.00000177780.000007936.60714 .k1.0008010532.00000157980.000007052.67857水冷器出口气相水冷器出口液

29、相%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.09351940.7896514111.84468629.99307 I.NH30.95417449.434356741.51532300.96051CH40.167581686.0245925290.368901129.03433 .CH40.020449.62741144.411106.44692Ar0.01150115.659891734.8984277.45082 .Ar0.000410.192112.881580.12864H20.523045262.3031978934.547923523.

30、86375 .H20.019038.96281134.442086.00188N20.205212064.6282730969.423981382.56357 I.N20.005952.8033342.050021.87723合1.0008410060.98000150914.700006737.26339 .卜1.00000471.019687065.29518315.41496氨分出口气相放空气%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.09351940.7896514111.84468629.99307 I.NH30.0935121.3199

31、9319.7999214.27678CH40.167581686.0245925290.368901129.03433 .CH40.1675838.20837573.1254925.58596Ar0.01150115.659891734.8984277.45082 .Ar0.011502.6210639.315941.75518H20.523045262.3031978934.547923523.86375 .H20.52304119.253311788.7995979.85712N20.205212064.6282730969.423981382.56357 I.N20.2052146.78

32、821701.8231531.33139合1.0008410060.98000150914.700006737.26339 .卜1.00084228.000003420.00000152.67857氨分出口液相冷交二入%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.95419449.441216741.61814300.96510 .NH30.09351919.4696513792.044761209.82849CH40.020449.62624144.393546.44614 .CH40.167581647.8162324717.243412168.

33、17925Ar0.000410.192022.880260.12858 .Ar0.01150113.038831695.58248148.73531H20.019028.95880134.381935.99919 .H20.523045143.0498977145.748326767.17091N20.005952.8017542.026231.87617 .N20.205212017.8400630267.600842655.05270合1.00000471.020017065.30010315.41518 .卜9832.98000147494.7000012938.13158冷交二出气相冷

34、交二出液相%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.06484618.645089279.67625414.27126 .NH31.00000300.824574512.36851201.44502CH40.172721647.8162324717.243411103.44837 CH40.000000.000000.000000.00000Ar0.01185113.038831695.5824875.69565 .Ar0.000000.000000.000000.00000H20.539085143.0498977145.748323444.0

35、0662 I.H20.000000.000000.000000.00000N20.211502017.8400630267.600841351.23218 .N20.000000.000000.000000.00000合1.000009540.39009143105.851316388.65408 .卜1.00000300.824574512.36851201.44502冷交出口液氨氨冷器进口气相%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH30.98425616.081979241.22960412.55489 .NH30.05005618.645089

36、279.67625414.27126CH40.005373.3615350.422892.25102 .CH40.136751690.1012325351.518411131.76421Ar0.000200.122731.841000.08219 .Ar0.01029127.133831907.0074885.13426H20.007934.9657874.486773.32530 .H20.583777215.01489108225.223324831.48318N20.002811.7604526.406811.17888 .N20.219142708.4950640627.425841813.72437合1.00000625.939289389.08927419.15577 .p1.0000012359.39009185390.851318276.37729氨冷器进口液相球罐进口液相%NM3/tNH3NM3/hKmol/h%NM3/tNH3NM3/hKmol/hNH31.00000300.824574512.36851201.44502 .NH30.971021065.5163315982.74492713.51540CH40.000000.000000.000000.00000