Korean Chem. Eng. Res., Vol. 45, o. 1, February, 2007, pp. 25-31 l s m k n Šk oy ÇmzsÇ Ç p n 151-742 ne k e 56-1 (2006 11o 16p r, 2006 12o 13p }ˆ) Optmal Hydrogen Recyclng etwork Desgn of Petrochemcal Complex Changhyun Jeong, Chul-Jn Lee, Dae-hyeon Km and Chonghun Han School of Chemcal and Bologcal Engneerng, Seoul atonal Unversty,GSan 56-1, Shnlm-dong, Gwanak-gu, Seoul 151-742, Korea (Receved 16 ovember 2006; accepted 13 December 2006) k h o v l o q ro q p l ql p pp, p q~rp l n p. l n p l vop o ˆ rp o q n n, q p l n p. l l o v q q n o m. p l l n p n rr p Ž k, o l n n ˆ rk s p r r l }(source)m n}(snk) q l rp q n o o m. Abstract In a petrochemcal complex, large amount of hydrogen s produced as a by-product and used as a fuel n petrochemcal and ol refnery plants. By recyclng ths byproduct hydrogen as a raw materal, the value of hydrogen can be greatly mproved. Ths paper proposes a desgn methodology for optmal hydrogen recycle network between plants n petrochemcal complex by analyzng the hydrogen pnch, requred cost and constrants. Key words: Hydrogen etwork, Hydrogen Pnch, etwork Modelng, Optmzaton 1. l k ~ rs, l rv, l v p kl p n pp, l l kl ~ p n rp v p p. o v l o q ro q p l ql p pp, q~rp l n p. p l n p l vop o ˆ rp o q n n, q p l n p. q n l l l l n (pnch analyss) p k l l v l m. p Lnhoff ll rp l v sl r k l l p n p [1], m k r r l rp p r lm [2-4]. Towler p l v l n p o To whom correspondence should be addressed. E-mal: chhan@snu.ac.kr }pp n m [5], Alvesm Towler p re ož Ž np o rp p rk m [6]. p p Hallalem Lu ro r l ƒ MILP o p rk m [7]. Lum Zhangp o l rr q p r k m [8]. l l o v r~rp q n o o r p re m. n n l o n s p r, o l n q n ˆ p rk s p l r ep l o v q np o r o m. 2. m n ql q n o Fg. 1l ˆ p k. n q n o n ql n p o 25
26 r} Ëp~vË Ë s Fg. 2. Typcal structure for hydrogen recycle network. Fg. 1. Hydrogen network overvew. rr q n, p p o Žp p k p n. l n ql ~ l np lk, n ql o p p o p o k p k. p r o, q n o p n, p nl rrp q n o l r p rl np. 2-1. om om o v l l n /r p q n o o p p r rp. 1) qp p }(source) rp, n qp n p n} (snk) rp. 2) p l l q n l n, p o rr rp lv, l f n. 3) n l vr q n, rr rp n, p Ž l~ n l p l n. 4) r rr q l rr, n l f n. plp q n p l n p l Fg. 2l ˆ p 2 v n l p. l n p r k p n p qp sq, p p r p l Žp p k o p. l n p k n l n p p o rr q m p o Žp p k k. 2-2. (hydrogen pnch) l l p l v p v l rn ƒ p. k p l, v, ož Ž edš qp l rn lm. o45 o1 2007 2k Fg. 3. Hydrogen composte curve [6, 7]. rl p }(source)m n}(snk) }, p np p p l p }. } p rp p, n} rp. }m n} }kv p Fg. 3 l ˆ } (hydrogen composte curve) p. p p m m lˆ e e p m o p e p rn p rp p l v m. p p r p ˆ d r lp p t. l Fg. 4. Hydrogen surplus dagram [6, 7].
n p t~ p }m n}p r p p, p p n p ˆ. on Fg. 4p pl (hydrogen surplus dagram) p. pl l rp n l o p p ˆ t. p p vrrp np r~rp n seˆv rp rr q p n l r pn p. v, pl l n } p p p n rr n}l p. 2-3. n l n (mathematcal programmng) r p x, r f(x), r s p lv r r. p rp p r s p seˆ xp o kl f(x)p p p xp p } p p. erp ˆ p. Mn x f(x) Subject to h(x) = 0 g(x) 0 where x T =[x 1 x 2 x k ] h T (x) = [h 1 (x) h 2 (x) h n (x)] g T (x) = [g 1 (x) g 2 (x) g m (x)] (1) rp p r m rks l LP(lnear programmng), LP(nonlnear programmng), MIP(mxed nteger programmng), MILP(mxed nteger lnear programmng), MILP (mxed nteger nonlnear programmng) p lv. q n o p o sl pv (bnary varable) m o l nl p MILP p lv. o m s(superstructure) rp o kp rk p, rp s k. o p kr p ov o n}p p } vrrp o l rn rr q o. p rk p r o tl r p rp o }. 3. m k Šk n o v l q n tn p q n p p p llk. lp o l rp p p l o q nl l ppp lp plk. q n r o } o r p r q n p f lp p ppp ˆ. p q n p f l p ~ o l p n, rr o rr q, n o Žp p k q n o n np l, }l q n p kp sr l q n p f lp p l ppp p r o v q n r o 27. l l n r r p p p r l r m. 1) l v rp v o l l. 2) p n p p n n l~l p. 3) l~ p lpv k. 4) o n p k. 5) p n o l~l p p r. 6) o e k }l sq k n, nr n p. 7) q }l pl l f n p. 8) ~ l np q e l o n. 9) rp r rs p ˆ p kp l p l p ˆ p k j l o p f r~rp p ˆ p kp p r. 10) p }(source) = {Î = 1,2,Ë,}p ˆ, p kp W, y. 11) p n}(snk) = {jîj = 1,2,Ë.,M}p ˆ, n p kp, z j. 12) rr r(ntermedate) = {kîk = 1,2,Ë,K}, n p rr. op p l r p r p p r. Max proft functon F = M C W j j = 1 C Compressor C ppe C fuel value W fuel, C fresh W fresh, j C PSA sr }l n} k(w)p sr p f r seˆ o }k. op r l v vep n p. p }(source)l p n n}(snk) vr, rr rp lv, q~rp l n n p. W M W j j p n}(snk)l n }(source) vr, rr rp rr, n l~ p l p p. n = + W, fuel + W = k p n}l p p p ep l lp p. G n n j z j W j + W kj + W fresh, j = W j y + W kj y k + W fresh, j y fresh j = 1 Korean Chem. Eng. Res., Vol. 45, o. 1, February, 2007 M (2) (3) (4) (5)
28 r} Ëp~vË Ë s p v n}l p m p p n}l n s p se k. mn n max ( n}l p n n ) (6) pp. pl rr kp v. pl tn pq n p ˆ m nr p q p k rk ˆ, q lm p p. mn n max z j z j z j ( n}l p n n ) (7) p l n l p k rr l r ks p. M j = 1 W fresh, j W k = 1 + = Pnch 3-1. h} (compressor) o o k p p p lrk. k p nr np, C Compressor = 0.746 P bhp C kwh h year µ P bhp : brake horse power C kwh : electrcty cost h year : operatng hour µ: effcency Brake horse Power Peter and Tmmerhaus p ~p l k l p p rk m [10]. 3.03 10 5 --------- γ P γ bhp = ---------------------------P (10) ηγ ( 1 n F -------- out 1 ) P n γ: rato of specfc heat of gas at constant pressure to specfc heat of gas at constant volume η: effcency P n : ntake pressure P out : fnal delvery pressure F: the flowrate beng compressed k l np Marshall and Swft ndexl p p r l p. a, b: cost parameter o45 o1 2007 2k γ 1 C comp [ kus ] = a comp + b comp Power comp [ kw] (8) (9) (11) 3-2. PSA rr t v p PSA(pressure swng adsorpton), (membrane systems), rm (cryogenc systems) p. p p o pn l p l r p n. rp rp ˆ p rrp k rp kr, e, kp p v l l r. rr q l tn pq q l p R = ( 1 θ) ------------------------ 1 ( P H P L )y f R: Hydrogen recovery θ: Adsorbent selectvty between 0 and 1 P H, P L : hgh and low pressure of PSA y PSA,f : PSA feed purty (12) pp l rr p p ˆ p. W k,fuel = ( 1 R) W k, (13) p rr rl p }l p m kp v p. W n n k y k = W k y ( rr rp lm p v v) (14) mn n max W k W k W k (rr p n n ) (15) mn max y y ( p n ) (16) k n y k k o PSA q n o k p rr p m k, o p rr, p k rr p k, q l n, q p nr s p. p n l p PSA q p q n n r nl m p. Ruthven p rr q p np r Shortcut p rk m [9]. Towler p rk Shortcut p q p nr s p re [5]. 0.4330 C PSA [ US ] = --------------- + --------------- 0.2986 C F n,psa Y Z PSA = a PSA + b PSA F n,psa (17) F: flowrate Y: recovery yeld Z: feed mole fracton of hydrogen a,b: cost data 3-3. (ppelne) o o q Žp pp e n. q l r p pp l pv, q v p o pp l p p n p. sp o l~l pp n n, p np p. Žp p np Žp p v l p. Žp p v p r n o~p, o, l p r.
Žp pp nl ep Peters and Tmmerhaus rk p Žp v p r l p r [10]. Parker Žp p nl Žp p q n, n, ˆ q p l e rp l p np rk m [11]. C Ppelne (da, length) = [a(da) 2 + b(da) + c](length) + d (18) da: ppe dameter(nch) length: nstalled dstance(mles) a,b,c,d: cost data Žp p v p l r. Žp p nl k p p Žp p v p nl tp v o lv p kl p v p v r p p. o vp n, l v Žp pp o q l. l vp n, p Œq Žp (ppe rack)l p np v lp. Žp pp Ž p p p k. Fg. 5p p, Žp p p l p r q, vr p Žp p vr p Žp. 3-4. o v p p, }l d, LPG p o l dž v pp ep k 70Í p p v p. p rp p o o p, n ož Žp n, q n, ˆ nr n p l p r. pt o p p v tp 80Í p p o e p q p p r rp v p. pl p p rp vrrp p m 30~50Í p r. p p p 80Íp p r, p l p n l p p r. o v q n r o 29 4. q n o l p Table 1. p lp qp 6 p, n p r p 5 p. pnl p p l ~ sq, p 99.9999Í p p r. o o n }m n} p Table 2l ˆ p. 4-1. tlv rl Fg. 6. o v l n p (99Í p ) p l pl l l pl p p(-)p p Table 1. Process data of snks and sources Flowrate(m 3 /hr) Purty( ) Source 1 10,000 99.9999 2 15,000 99 3 12,000 95 4 15,000 95 5 8,000 75 6 10,000 75 Snk A 15,000 99.9999 B 25,000 95 C 15,000 99 D 8,000 99 E 10,000 99.9999 Table 2. Dstances between sources and snks (km) Snk A Snk B Snk C Snk D Snk E Source 1 6 2 1 3 12 Source 2 3 1 4 6 15 Source 3 15 11 8 6 3 Source 4 11 7 4 2 7 Source 5 1 5 8 10 19 Source 6 13 9 6 4 5 Fg. 5. Evaluatng dstance between sources and snks. Fg. 6. Constructon of a hydrogen composte curve and a surplus dagram. Korean Chem. Eng. Res., Vol. 45, o. 1, February, 2007
30 r} Ëp~vË Ë s Fg. 7. Feasble hydrogen composte curve and a surplus dagram. ˆ p p p. p q o o p k pnl p p kp n p k t. q o l }m n}p p l p p. }(source) l p f pl l p kp p e rp ˆ p p p p p rp. Fg. 7p p } ˆ n lt p. Òp n n l o p ppp p p n ˆ p, Òp n rp ˆ n l p p r p np. rp n l n p p k t v p. rp p p kp. r k p r r l rr o rr q p n p k t. rr q l rr n l p p m l PSA p n p r p. p l r p n p r l rk s p l r o l t n l p. 4-2. m k n Šk q n o l r rp m s(superstructure) Fg. 2l ˆ p. n q n r o rp n p p r o p p kp pp p p l. p r~rp p p rr n l p k p, r r l np Table 3. Hydrogen network matrx wthout purfcaton process Snk A Snk B Snk C Snk D Snk E Fuel Source 1 10,000 0 0 0 0 0 Source 2 0 0 15,000 0 0 0 Source 3 0 10,000 0 0 0 2,000 Source 4 0 15,000 0 0 0 0 Source 5 0 0 0 0 0 8,000 Source 6 0 0 0 0 0 10,000 Fresh 5,000 0 0 8,000 10,000 0 o45 o1 2007 2k Table 4. Hydrogen network matrx wth purfcaton process Snk A Snk B Snk C Snk D Snk E Fuel Source 1 2,000 0 0 8,000 0 0 Source 2 0 0 15,000 0 0 0 Source 3 0 10,000 0 0 0 0 Source 4 0 15,000 0 0 0 0 Source 5 0 0 0 0 0 0 Source 6 0 0 0 0 0 0 Fresh 3,000 0 0 0 0 0 PSA 1 0 0 0 0 0 0 PSA 2 0 0 0 0 0 0 PSA 3 2,000 0 0 0 0 0 PSA 4 0 0 0 0 0 0 PSA 5 8,000 0 0 0 0 0 PSA 6 0 0 0 0 10,000 0 p ~rp o p p. r (solver) What s Best n l p m. Table 3p p np rn r r l r o (matrx)p. p p }l n} kl ~rp r ˆ. Table 4 rr q l o p. PSA p }l rr q rr n} kp ˆ. v }l q, q l n } o p. p rk s l p r p m l rk s p seˆ n pp p. p l p v kp n rp kp rp l l n p p kp t p p. q np l r~rp rr ppp rlv. p rk s p l n}p p } p p p s r r. rr q o p l v kp nm srp p v k. p p n p p rr l rk s p l, o srp l m p v, nl o l qp ppp p p. o l rrp Table 5l ˆ p. o v kp nm, o v q n r o n p Œq np rn l 190lol 330lop lp p. Œq le 0.4~0.6 p ˆ Œq nl Ž rr v ppp k p. p l fp l om l p l ~ l op l p r. q B-Cop l p, p l fp p k 40Í p lv o p f rrp pp p lp p. l op p o p m p p
o v q n r o 31 Table 5. Hydrogen network results Exstng etwork (no network) ew network 1 (wthout PSA) ew network 2 (wth PSA) Hydrogen Purchased Costs ƒ 156 bllon/yr ƒ50 bllon/yr ƒ6.5 bllon/yr Hydrogen Fuel value ƒ 70 bllon/yr ƒ17 bllon/yr ƒ0 bllon/yr Captal costs Ppelne - -ƒ8 bllon/yr -ƒ14 bllon/yr PSA - - -ƒ7 bllon/yr Compressor(operatng) - -ƒ0.1 bllon/yr -ƒ0.2 bllon/yr Fuel costs - -ƒ53 bllon/yr -ƒ70 bllon/yr Hydrogen Sellng Proft - ƒ76 bllon/yr ƒ111 bllon/yr EP(economc potental) - ƒ19 bllon/yr ƒ33 bllon/yr Payback perod - 0.4 years 0.6years l l op p d p n ˆ p. l l rk q n o p p p p l fp r l p p, l p p kr kv n q n l o n l f n n j rrp. p l m p o v l n q n n p rrp r m p Ž, pl rp q n o p q nl sp kp n p Ž. 5. l l o v l l n p np p p p o r r o p re m. p o r p o }(source)m n}(snk) rp l o k tl pn o l n p kp rp l n o p np r neˆ pl. p p rr p r, o p np o q n p n r l ~rp o m. re o l pl p np l rrp ppp v p p p. q p o kp rk mv l ql rn o q p p v, r rp q rn, rk o l lp n l l m vp n. l lqo ~r vo (KCPC)m n k l p k l (BK21), l o (KIST), l v (l v qo l), q ( r l, R01-2004-000-10345-0), q vr pm l (AEBRC, R11-2003-006) p l vop lp pl. y 1. Lnhoff, B., Townsend,D.W., Boland, D., Hewtt, G. F., Thomas, B. E. A., Gut, A. R. and Marsland, R. H., User Gude on Process Integraton for the Effcent Use of Energy, Ins. Chem. Eng., Rugby, UK (1982). 2. Lnhoff, B., Pnch Analyss: A State-of-the-Art Overvew, Chem. Eng. Res. Des., 71, 503-522(1993). 3. Shenoy, U. V., Heat Exchanger etwork Synthess: Process Optmzaton by Energy and Resource Analyss, Gulf Publshng Company, Houston(1995). 4. Smth, R., Chemcal Process Desgn, McGraw-Hll, Y(1995). 5. Towler, G. P., Mann, R., Serrere, A. J-L. and Gabaude, C. M. D., Refnery Hydrogen Management: Cost Analyss of Chemcally- Integrated Facltes, Ind. Eng. Chem. Res., 35(7), 2378-2388(1996). 6. Alves, J. J. and Towler, G. P., Analyss of Refnery Hydrogen Dstrbuton Systems, Ind. Eng. Chem. Res., 41(23), 5759-5769 (2002). 7. Hallale,. and Lu, F., Refnery Hydrogen Management for Clean Fuels Producton, Adv. Enc. Res., 6, 81-98(2001). 8. Lu, F. and Zhang, F., Strategy of Purfer Selecton and Integraton n Hydrogen etworks, Chem. Eng. Res, Des., 82(20), 1315-1330(2004). 9. Ruthven, D., Farooq, S. and Knaebel, K., Pressure Swng Adsorpton, VCH, Y(1994). 10. Peters, M. and Tmmerhaus, K., Plant Desgn and Economcs for Chemcal Engneers, McGraw-Hll, Y(1991). 11 Parker,., Usng atural Gas Transmsson Ppelne Costs to Estmate Hydrogen Ppelne Costs, Ol & Gas Journal s annual Ppelne Economcs Report(1991-2003). Korean Chem. Eng. Res., Vol. 45, o. 1, February, 2007