Summary Correlations from Feedstocks & Products

Transcription

1 Summary Correlatons from Feedstocks & Products. API gravty (G) & specfc gravty ( o ). Hgher densty lower API G.5 o.5g o. atson characterzaton factor. endences: (paraffnc) to 0 (aromatc) K o n unts of R. Blendng rules Volume lendng VX X mx v X V X mx Mass lendng mx w X m v o vo X 4. Blend specfc gravtes drectly y volume Volume lendng Vo, Vo, v V V Alternate lendng w M xm omx, o, omx, o, omx, o, 5. Blend API gravtes lend specfc gravtes & calculate from lended value 6. O Donnell method to correct lqud specfc gravty for temperature o wth n F Multply y the 60 F water densty to get the densty at the temperature. Orgnal equaton n terms of lqud densty: wth n C, n kg/l, & near 5 C o Method n Chapter. of API Measurement Manual to estmate volumetrc shrnkage V S C C G G C V V L L H where 00 H L John Jechura, jjechura@mnes.edu CBEN 409, Rev. - - July, 08

2 8. Maxwell-Bonnell equatons to correct olng pont for pressure ( n R & P n mmhg) log 0 P X X X P.7 mmhg 66.9X X X mmhg P.7 mmhg X X 6X mmhg P P X & B B.5f K log B f P 760 mmhg B Mn,Max,0 P 760 mmhg Interconvert D86 & BP emperatures 994 API echncal Data Book method ( & n F).058 BP,50% D86,50% BP,50% D86,50% B A ( & n F) BP D86 BP D86 Vol% A B Max [ F] 00% to 90%* % to 70% % to 50% % to 0% % to 0% % to 0%* Interconvert D60 & BP emperatures temperatures evaluated at 0 mmhg 4 a c d BP D60 D60 D60 D60 John Jechura, jjechura@mnes.edu CBEN 409, Rev. - - July, 08

3 Vol% Dstlled Range a c d 0% - 0% %-0% 0%-50% Raz equaton to smooth dstllaton data 0 A B B 0 B ln Y exp 0 B Y A 0. Excel functons to nterpolate/extrapolate dstllaton data ransformed Yeld: =NORMSINV( Pct_Yeld/00 ) From nterpolated value: =NORMSDIS( Value ) * 00 Functons return errors for the extreme values of 0% & 00%. ypcal practce s to use 0.% & 99.9% nstead.. Estmate molecular weght of narrow petroleum fracton M B o exp B o B o 4. Estmate heat of comuston of petroleum fracton (Btu/l, lqud 60 F) Hˆ G0.7G 0.009G LHV HHV Hˆ G0.6G 0.004G John Jechura, jjechura@mnes.edu CBEN 409, Rev. - - July, 08

4 Heatng values for the or state must take nto account the heat of orzaton at the reference temperature. 5. Approxmate method to lend ndvdual atson K factors (y weght) K wk mx v K o v o 6. 5 defntons for dfferent types of average olng ponts: n Volume average olng pont (VABP) v v, n eght average olng pont (ABP) w w, n Molar average olng pont (MABP) M x, Cuc average olng pont (CABP) Mean average olng pont (MeABP) v n cuc, mean M cuc 7. Estmate average olng ponts from ASM D 86 dstllaton values (n F) VABP SL 90 0 ABPVABP MABPVABP CABPVABP MeABPVABP John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

5 ln VABP SL ln VABP.0479 SL ln VABP.8858 SL SL 0. ln VABP Vapor pressure approxmaton usng acentrc factor defnton P 7 c log0 Pc 9. Volumetrc lendng wth RVP Blendng Indces RVP RVP RVP RVP mx v mx v /.5 0. Non-lnear octane lendng equatons Ethyl Corporaton models A s %aromatcs (0 to 00) & O s %olefns (0 to 00) RRa RJRJa O O a A A A A MM MJ M J O O 00 R M "Road" Octane Senstvty J RM v X Volume Average X v 75 Blends 5 Blends a a a Drvealty Index DI.5.4 F EtOH vol% John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

6 . Estmate Flash Pont For pure components or well defned pseudo components Method of Lenor N xm P. where s the lqud actvty coeffcent Method of Gmehlng & Rasmussen x P 5 N wth L L5 C 0.8 L Hc, For petroleum fracton characterzed y dstllaton curve API Procedure B7. (usng ASM D86 0 value) 999 Verson (unts of F) F Verson (unts of R). Questonale accuracy aove 0 of 500 F ln F 0 0. Estmate Cetane ndex y ASM D 976 (usng ASM D value n R) Index G 0.9Glog 65.0log Relatonshp etween octane & cetane numers CN MON CN RON 5. Interrelate SUS vscosty wth cst vscosty ( n F) SUS John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

7 6. Adjust knematc vscosty for temperature usng alther equaton. Provdes a framework to regress vscosty data wth respect to temperature. A B AB 0 log log log 0.7 log Can also use natural logarthms: A B A B ln ln 0.7 ln exp exp ln Adjust vscosty for temperature usng ASM D4 for vscostes aove 0. cst. An adjustment to the shft factor of the alther equaton for applcalty to vscostes lower than 0. cst. Z ABlog log log Z 0.7 CDEF GH C exp D exp E exp F exp G exp H exp Z 0.7 exp Z Z Z Blend vscostes log-log method as volume lend log log 0.7 mx V v mx mx V ll also work wth natural logs: 0 mx ln ln mx 0.7 V mx v mx expexp mx 0.7 V ASM D 75 extends the valdty of method to lower vscostes John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

8 v Z 0.7 exp log log Z B 0 B ZB Z exp Z 0.69Z 0.9Z B B B B B Chevron Method. Volume lend the vscosty ndces: ln ln 000 V mx v ln ln000 V mx mx 9. Relatonshp of Ramsottom to Conradson Caron RCR exp ln CCR ln CCR Addtonal Useful Correlatons 0. Crtcal temperature & pressure for a narrow olng fracton. Lee & Kesler method also pulshed as Procedures 4D. & 4D4. (4 th ed., 987). emperatures are n R & pressure s n psa exp c o o o mx. Heat of Vaporzaton. Kstakowsky equaton (he Propertes Of Gases And Lquds, rd ed., p 5): John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

9 Hv 8.75 Rlog c where temperatures are n unts of K & the heat of orzaton are n unts of J/g.mol. he effect of temperature can e estmated usng the atson method (he Propertes Of Gases And Lquds, 4 th ed., p 8): r Hv Hv r 0.8. Predcton of knematc 00 & 0 F. Correlaton y Aott ncluded n old edtons the API echncal Data Book: K K log 00F G.8460 KG 0.767K 0.994G G KG G K 4 log 0F G G KG K.4899G0.9768G G K where the unts on knematc vscosty s cst. However, ths technque does not extrapolate well & s only vald for olng ponts F or so. Once these values are known then the temperature dependency can e determned from: John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

10 c A B log log 0.7 log c f.5 cst 0 f.5 cst he latest API echncal Data Book (0 th ed.) has a etter Procedure.A4.: 0 log log 4 7 ref A A K A A cor 00F ref cor log log 0 0F 0 00F where the olng pont s n unts of R. he recommended equaton to modfy these vscostes wth respect to temperature s: 0 0 S log o where S log log hs procedure gves vscosty curves those shown elow.. Freezng pont, pour pont, & cloud pont. If knematc vscostes are not known then Procedures C5., C, & C6., respectvely (0 th ed. API echncal Data Book) can e used:, K 0.5 MeABP. FP R o MeABP 0.o pour R,.850 MeABP 0.4. John Jechura, jjechura@mnes.edu CBEN 409, Rev July, 08

11 0.5 log log MeABP 0.7 MeABP CP, R 0 o If knematc vscosty s known: F pour, R 756 e 57o F 0.9 MeABP. If cloud pont s known then (Procedure C8.): pour, R CP, R he correlatons usng MeABP, specfc gravty, and/or atson K factor are depcted n the followng fgures. John Jechura, jjechura@mnes.edu CBEN 409, Rev. - - July, 08