Topic 5- Liquefaction example.pdf

Topic 5- Liquefaction example.pdf - ChemE 3130 — Lecture...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 10
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 12
Background image of page 13
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ChemE 3130 — Lecture 10: Topic V — Application of 1st and 2"d Law to Cyclic Processes. Liquefaction The liquefaction of gas is an important industrial process. Natural gas processing (to produce liquefied natural gas, LNG) and processing of refrigerant gases are just two examples. One approach to liquefying the gas would be to just cool it, isobaricaliy, until the gas condenses. However, this approach is too energy (and cost) intensive in most cases. A better approach is to first pressurize the gas, cool it at the high pressure and finally pass it through a Joule-Thompson expansion valve, which produces a mixture of liquid and gas. We will consider a specific example of LNG processing. Since natural gas and LNG are high volume r“ low margin processes , small improvements in the process efficiency can significantly distinguish your processing costs from that of your competitor. Your task is to produce LNG, which we assume to be pure methane from a gas at 1 atm and 280K. You are asked to evaluate two processes: (i) the simplified and (ii) Linde liquefaction process. The following process specifications are given: - Methane leaving the cooler (point 3) is at 10 MPa and —80°C. - The J-T valve and the flash drum operate are well insulated. — Compressors are assumed to operate reversibly and adiabatically. - Since the compression ratio is very large, interstage cooling is required. A three-stage compressor with interstage cooling is available. (i.e. the first stage compresses the gas from 1 atm to 5 atm, the second from the second stage from 5 atm to 25 atm, and the final from 25 atm to 100 atm (~10MPa)). Between each stage, the gas is cooled isobarically to 20°C. To compare the efficiency of the simplified and Linde liquefaction process, determine the following: (a) The amount of work required per kg of methane that passes through the compressor in the simple liquefaction process (i). (b) Calculate the fraction of liquid and vapor leaving the flash drum in the simple liquefaction process and the amount of compressor work required for each kg of LNG produced. (c) A suggestion to improve the simple liquefaction process is to recycle part of the cold gas flashed in the tank. Assume a 10°C approach temperature in the heat exchanger and calculate the amount of work required, per kg of LNG, with the improved process. I , r -#-!_ I P” L3 3% 41""’°"5L‘ 42¢: me"59 9"- 0.3 Gé 0.4 0.2 Gd {L33 9.06 MM £1.02 0.01 160°C! Based on fimzht'mn of &t2mann and Wagner [1991] +ng'mn 2 twain-n 5'1! R-SG (Methane) mm 3'}. 9g; .3 Q; 3" '-_ E .. 6% 3; Eg E a“ i3 '12: : a 1.. Pmperfimmmpmed with: M517 REme rm “gamma 'sassaamd 3mm 01 M91 puz pue “I ;o uoneaglddv — A agdoi :01 91:11:31 — 05:5 awaqj can a: ~133$ 3 E727 Gog Q ¢¢DQ a a Based an finrmuhfiun of 5911mm and Wagner (1991? mm Hm version 78 11—50 [Methane] Wanna 1; = motifs“ = 0m HIM-K3- __ mum at m mama helium perm _j‘_ -3m . Pram computed with: MST REFPW'X’ {3.91 ' um “mmmfi 39-3533on auafo 0:, ME] p“: pue 15'; 4o uoneanddv - A agdol :0: amps-l — 02:5 gnuan Baud cm Emulation of Sebmuann and Wagner (1991; EMHFM version 73 12-59 (Methane) Wm state: 1. : outlaw: um kltéka'fl EE 3.. 3'. tie a; campuénd with: MST REPPRm Em ‘musmd 'sassaamd snot) 01M21 puz pue Is: #1 uoneagtddv — A 3§dO_|_ :01; sumac-n — 091:9 3|.LI9LD g. : “I”t (L‘IQU‘l-“hlftfl :VV} I ('3 W535 = m. (“60 #0100): m ’260 LC: LT J W511; '1- :MJ (“YO "—8-;0) gm" r240 k/(G. *fie «Tng ,5” (Lani; ”q1;1:::-g;ma—m_. -. Werw = Wewwswwfl = ’M Pym" ream PWSSPJ 71/15 {3 4W2 war». {Dar LC EYES) \ bafiffi" UJQ (“hick/teak MG: 50! (25—, Rover-{woe To comfme m 07m; \UOF\L Par pg L bog} we Com gflo e’vé’m bAflw. Nae “RNA”? (:5) f:- A A, 460%, l( we 092 an"; 54mm Cb (Cd mam QALQF, we JAPQ (:33 4o 4L2 “SL4 3L, «(Le (P# H mad [mle/ mote Me‘flnaIAé‘ P.g_(— P653”; y Le: a 5€Q l/IOUJ Much! r‘mpmwéméwl rib War-«[Qed’, (V1 (Ow (:rbuwc41’an (if) I? Lr‘w-ofle Afr-preys. I M .t,‘ (Mfg {)1 {flflefii’ g? 5-; r-i-flgx- 52.1" 40 (00' ® V g1, YecQK/Cr'vg 4W 49”" Paw}! "'6 O-C ® 4° Mpg/=95 0UP ([rfim‘c’ which“ P49 r” of 4395 P1 oafiésfcf, m r1333 33 a 5*“ g3 53 «y'all N Q chfiam £3 M ' “E . . . \ . . . . \. a ...... .. 'U E 'a £3 a “5 .... ._ g E «B E 3 3;: 3‘ IE version 73 R—é’rfl (Methane; 2mm _ $3.: I E?“ gig M 5. 3E fi: 2 Pmpertia equaqu wanna REFPRCJP 3M ‘mmmd ‘sassanmd alpha 01 M21 puz pue “I 40 uoneauddv «— A agdol :01 ampa'l — 0519 awaqj I <9 [NHL] Q Pflmc-[A J‘é'mchAp-«e 51K {O'g’(:,l {he gawk OM _\ ’“AQ Pfeui'ovs [Fe $LOW§ WQ ("03:01 chtzuzi‘ue fl?“ Cl t f @ Jib-QM — [609 “(O arr‘N’tf/f 0 9°2r€c2ma 3 l ( h3 Z 1' cover “Mme Wu; Let: ' WCLHDW cg M . we “I, 5:; (Lu/C calf figvtfq'wfi “YO (QQI-LG—Vm. g l: nu) VVf/QCL mg: héné’o! 40 090 «(he maze} /gfla/S/ ,O k = 2’52 ICE-L5" 1r. Pl‘haflk/ WE [AOL-U6 réqviremé’m‘L' as, [9?th W55/é’t/{Qr57/ lac-(Q9103 ‘. A5 bfG’fl‘Q‘ UU€ 0&(CU(&(€ 9m 4% PM we “{O {€.C<:(C—u\-C“((f 4‘4 éc‘Q—G {~30st— : (ofiikisz’o) Jr (VOW-XS) — (OTC H [@— MLDLED ms'b‘s‘ Jr mil"! ehfl;'(fl@b5)+ U»%X€7C% 74o (c3,\a3" N..— Qom al'Le ‘P—H H”J W9 (Lo. SLO VJOFL ‘(SOC @ncha-“OM "We. Lwole PW‘chfis «At/Jr Lia-‘2 (Ob/€34 WOV‘? Roar/“re W€W+ 0095 a—C ’DIOClL/(‘POL The Lcwoe fwocess» Prowfog€5 a <30 { €K€(?mv0(< {Or {06.955 [la/1 Prove MGM 5 May'va C Que! kg.ch ‘mlesmc’kow, Ddafb 032 We} 1k4e5+c4wrml PWQL'WLQJY aLQmL'k/x “dbl WUHfPlfl \ 53'}! 60mg { are (70Vé7yf’o/ IV! (Kné’m é SENEOr D995” my, (elafludy £490”qu opéwrlc‘d’rom F3 63095/{9/6_ {2w ewka we (‘Q-Vt C’L‘ahgé Oil/~01 Girl] 11 €H‘vaxa[ 090055 "(O {WC—'ch H6OOC W47! ...
View Full Document

Page1 / 13

Topic 5- Liquefaction example.pdf - ChemE 3130 — Lecture...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online