\$title Simplified Alkylation Process (ALKYL,SEQ=165) \$onText This model describes a simplified alkylation process. Note the modeling of error bounds on the estimated equations. This formulation is very efficient in terms of problem comprehension and solution. The additional nonlinearities are bounded in a narrow range and introduce no additional computational burden. Berna, T, Locke, M, and Westerberg, A, Simplified Alkylation Process. AIChE Journal 26 (1980), 37. Keywords: nonlinear programming, chemical engineering, alkylation process \$offText Variable F 'objective variable' OlefinFeed 'Olefins feed' IsobutRec 'Isobutane recycle' AcidFeed 'Acid feed' AlkylYld 'Alkylate yield' IsobutMak 'Isobutane makeup' AcidStren 'Acid strength' Octane 'Octane number' Ratio 'iC4 Olefin ratio' AcidDilut 'Acid dilution factor' F4Perf 'F4 performance number' alkerr octerr aciderr F4err; Equation Objective 'objective function' AlkylShrnk 'Alkylate volumetric shrinkage equation' AcidBal 'Acid material balance' IsobutBal 'Isobutane component balance' AlkylDef OctDef AcidDef F4Def; Objective.. F =e= - 6.3*AlkylYld*Octane + 5.04*OlefinFeed + 0.35*IsobutRec + AcidFeed + 3.36*IsobutMak; AlkylShrnk.. AlkylYld =e= (OlefinFeed+IsobutMak)/1.22; AcidBal.. 0.98*AcidFeed =e= AcidStren*((AlkylYld*AcidDilut)/100.0 + AcidFeed); IsoButBal.. 10.0*IsobutRec + IsobutMak =e= OlefinFeed*Ratio; AlkylDef.. AlkylYld*AlkErr =e= OlefinFeed*(1.12 + 0.13167*Ratio - 0.0067*Ratio*Ratio); OctDef.. Octane*OctErr =e= 0.8635+(1.098*Ratio - 0.038*Ratio*Ratio)/100 + 0.325*(AcidStren - 0.89); AcidDef.. AcidDilut*AcidErr =e= 35.82 - 22.2*F4Perf; F4Def.. F4Perf*F4Err =e= -1.33 + 3*Octane; alkerr.lo = .99; alkerr.up = 1/.99; alkerr.l = 1; octerr.lo = .99; octerr.up = 1/.99; octerr.l = 1; aciderr.lo = .90; aciderr.up = 1/.90; aciderr.l = 1; F4err.lo = .99; F4err.up = 1/.99; F4err.l = 1; F.l = -0.90; OlefinFeed.lo = 0; OlefinFeed.up = 2.00; OlefinFeed.l = 1.745; IsobutRec.lo = 0; IsobutRec.up = 1.60; IsobutRec.l = 1.2; AcidFeed.lo = 0; AcidFeed.up = 1.20; AcidFeed.l = 1.10; AlkylYld.lo = 0; AlkylYld.up = 5.00; AlkylYld.l = 3.048; IsobutMak.lo = 0; IsobutMak.up = 2.00; IsobutMak.l = 1.974; AcidStren.lo = 0.85; AcidStren.up = 0.93; AcidStren.l = 0.893; Octane.lo = 0.90; Octane.up = 0.95; Octane.l = 0.928; Ratio.lo = 3; Ratio.up = 12; Ratio.l = 8; AcidDilut.lo = 1.2; AcidDilut.up = 4; AcidDilut.l = 3.6; F4Perf.lo = 1.45; F4Perf.up = 1.62; F4Perf.l = 1.45; Model m / all /; \$onText optimal solutions OlefinFeed.fx = 1.70368; IsobutRec.fx = 1.58449; AcidFeed.fx = .543165; AlkylYld.fx = 3.03581; IsobutMak.fx = 2.0; AcidStren.fx = .90133; Octane.fx = .950; Ratio.fx = 10.4743; AcidDilut.fx = 1.56164; F4Perf.fx = 1.53535; m.holdFixed = 1; \$offText solve m using nlp minimizing f;