Note - this case requires compounds not available in Alph Jr.
This example demonstrates the use of a turbo expander to cryogenically recover ethane from a natural gas feed. See the more detailed description.
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"Tools" : [
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"minInnerStep" : 0.0001,
"Pressures" : [
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"Spec" : "#expander.p",
"Stage" : 0
},
{
"Spec" : "#expander.p + $dp",
"Stage" : -1
}
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"ovhdFormula" : "1000 kgmole/h",
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"Fluid" : "expout.l"
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"Spec" : "#.5.q / (#._1.q + 1e-10) - .75",
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"Temperatures" : [
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"Spec" : "-90 C",
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"Spec" : "15 C",
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"name" : "expander",
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"Feed" : "lts.v",
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"outP" : "2000 kPa",
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"inputPaths" : [
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"efficiency" : ".8",
"outP" : "{fromunit \"kpa\" \"p\" 2500} +\n#equatepower.0 * $dp",
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"CompFormula" : "[ 85,10,4,.6,.4,.3,.2,.2,.1,,06,.05,.04,1,.5 ]",
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"SecondPropType" : "H",
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"PROPANE",
"ISOBUTANE",
"n-BUTANE",
"ISOPENTANE",
"n-PENTANE",
"n-HEXANE",
"n-HEPTANE",
"n-OCTANE",
"n-NONANE",
"n-DECANE",
"CARBON DIOXIDE",
"NITROGEN"
],
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"PropertyFormula" : "30 Kpa"
},
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"DiagramY" : 298.4951,
"PropertyFormula" : "#demeth.5.q + #demeth.8.q + #demeth.10.q"
}
],
"CaseName" : "deep cut turbo",
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}