[學(xué)習(xí)]反應(yīng)工程基礎(chǔ)程易recyclereactor-循環(huán)反應(yīng)器

1、Recycle reactor（循環(huán)反應(yīng)器）,Plug flow, V,,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,Recycle ratio,R = 0, PFR,R = ?, CSTR,,,Recycle reactor（循環(huán)反應(yīng)器）,Attention：,,XA,=,,Moles of A reacted,Moles of A fed,For reactors in

2、 serieswith no side streams,FA0 at inlet (XA0 = 0),,Plug flow, V,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,Attention：,X,X,With side stream,i.e., the recycle stream,The formula is not applicable.,F’A1 is no

3、t the correct “FA0”,,Plug flow, V,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,,Plug flow, V,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,Conversion,Unknowns：,X’A1,X’A2,F’A0,,,,,,,,FA3,FA0?0XA0=0,,FA2

4、,,,,,P,Q,Assumption: a reversible transform,V*,,Plug flow, V,,,F’A0X’A0=0,,Plug flow, V,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,F’A1X’A1,F’A2X’A2,F’A0X’A0=0,,,,,,,,,FA3,FA0?0XA0=0,,FA2,,,,,P,Q,V*,,Plu

5、g flow, V,,,F’A1X’A1,F’A2X’A2,F’A0X’A0=0,,,,,,FA3,FA0?0XA0=0,,FA2,,,,,P,Q,V*,,Plug flow, V,,,F’A1X’A1,F’A2X’A2,F’A0 =,Feed rate of A if the stream entering the reactor (fresh feed plus recycle) were unconverted,=,

6、A which would enter in an unconverted recycle stream,A entering in fresh feed,+,=,RFA0,FA0,+,=,(R+1)FA0,?,F’A0X’A0=0,,,,,,FA3,FA0?0XA0=0,,FA2,,,,,P,Q,V*,,Plug flow, V,,,F’A1X’A1,F’A2X’A2,,?,F’A0X’A0=0,,,,,,FA3,FA0

7、?0XA0=0,,FA2,,,,,P,Q,V*,,Plug flow, V,,,F’A1X’A1,F’A2X’A2,?,,Plug flow, V,,,,,,FA3,FA0?0XA0=0,F’A1X’A1,,FA2,,,,,F’A2X’A2,P,Q,Mole balances,?,?,?,?,?,(at point P),(at point Q),,F’A0X’A0=0,,,,,,FA3,FA0?0XA0=0,,FA

8、2,,,,,P,Q,V*,,Plug flow, V,,,F’A1X’A1,F’A2X’A2,,,,,,,,,XA,XA1 XA2,,,,,,,,,,,,R,1,,,,,,,,,XA,XA1 XA2,,,,,,,,,,,,R,1,Recycle reactor:,PFR:,CSTR:,S4,,R ??: Recycle reactor ? PFR,R ??: Recycle reactor ? CSTR,,,,,,Smal

9、l R,1,,,,,,Large R,1,,,,,Autocatalytic reactions,Plug flow vs. Mixed flow reactors for autocatalytic reactions,Optimum recycle ratio, R,Theoremof calculus,,The optimum recycle ratio introduces to the reactor a feed whos

10、e 1/(-rA) value equals the average 1/(-rA) value in the reactor as a whole.,,,,,XA2,XA1,,,,,S,S2,,,,,,S1,S’,R,1,Recycle just right,,,,XA2,XA1,1. How about the situations for “recycle too high” and “recycle too low”?...,2