# rathore_hen.in
#
# Simple separation sequence synthesis example based on the problem
# described by Rathore et al, AIChE J, May 1974. This is similar to
# the problem described in rathore.in except that a wider range of
# operating pressures is allowed and in that we attempt to identify
# solutions which have positive aspects for heat integration.  This
# problem therefore takes a little longer to run than the smaller
# problem.
#
# Copyright (c) 2000, Eric S Fraga, UCL, All rights reserved.
#
# --------------------------------------------
#
# Give the synthesis problem a name and a description. These are used
# for report generation. All output will appear in a subdirectory
# named after the project name.
#
project RathoreHen
title "Heat-integrated separation sequence synthesis [Rathore et al., 1974]"
#
# tell the system where to find the classes referenced below
use jacaranda.design.ps		# for base stream and component classes
use jacaranda.design.units	# for the unit models and unit variables
#
# Define a constant used by the rest of the input file, specifically
# for definining the component discretizations.
#
variables
	constant Base 10 "Percentage component flow discretization"
	# define the flows of the components in the feed
	constant Fpropane  " 45.36 *kmol/hr"
	constant Fibutane  "136.08 *kmol/hr"
	constant Fnbutane  "226.8  *kmol/hr"
	constant Fipentane "181.44 *kmol/hr"
	constant Fnpentane  "317.52 *kmol/hr"
	constant FeedFlow "Fpropane+Fibutane+Fnbutane+Fipentane+Fnpentane"
end
#
# The feed stream consists of five hydrocarbon components. The base
# flow for each component is 10% of the total initial flow for that
# component. In other words, component flows will map to the nearest
# 10% of the initial flow. This is sufficient for the level of detail
# desired for this type of problem.  The main effect it has is on the
# purity specification of the final product streams.
#
KistaComponent propane
	base "Fpropane/Base"
	bp 230.8
	cpv -4.224 3.062e-1 -1.586e-4 3.214e-8
	lhtc "0.583 *kW/m^2/K"
	vhtc "5.0 *kW/m^2/K"
end
KistaComponent ibutane
	base "Fibutane/Base"
	bp 263.0
	cpv -1.390 3.847e-1 -1.846e-4 2.895e-8
	lhtc "0.583 *kW/m^2/K"
	vhtc "5.0 *kW/m^2/K"
end
KistaComponent nbutane
	base "Fnbutane/Base"
	bp 272.4
	cpv 9.487 3.313e-1 -1.108e-4 -2.821e-9
	lhtc "0.583 *kW/m^2/K"
	vhtc "5.0 *kW/m^2/K"
end
KistaComponent ipentane
	base "Fipentane/Base"
	bp 301.0
	cpv -9.525 5.066e-1 -2.729e-4 5.723e-8
	lhtc "0.583 *kW/m^2/K"
	vhtc "5.0 *kW/m^2/K"
end
KistaComponent npentane
	base "Fnpentane/Base"
	bp 309.3
	cpv -3.626 4.873e-1 -2.580e-4 5.304e-8
	lhtc "0.583 *kW/m^2/K"
	vhtc "5.0 *kW/m^2/K"
end
# 
# The feed consists of a single liquid phase made up of the components
# listed above.
#
Phase feedphase
	comps propane ibutane nbutane ipentane npentane
	x 0.05 0.15 0.25 0.2 0.35
	flow "FeedFlow"
	phase liquid
end
#
# Define the actual feed stream. We consider four pressure levels
# within the range 1 to 30 atmospheres.
#
PStream feed
	# the stream has one phase
	add feedphase
	# define the valid pressure range and number of values in that
	# range 
	prange "1 *atm" "30 *atm"
	nstates 4
	# and set the actual pressure of the stream to be 1 atm (or as
	# close as we can get in the discrete space).
	P "1 *atm"
	# map to discrete space
	map	
end
#
# Discrete utilities are available for both heating and cooling. The
# format of each line is:
# 
# 	type description Tin Tout TransferCoefficient Cost
# 
DiscreteUtilities utils
    hot  "Steam @ 28.23 atm"	503.5 503.5 "5000 *W/m^2/K" "1.0246 / GJ"
    hot  "Steam@11.22atm"	457.6 457.6 "5000 *W/m^2/K" "0.773824 / GJ"
    hot  "Steam@4.08atm"	417.0 417.0 "5000 *W/m^2/K" "0.573203 / GJ"
    hot  "Steam@1.70atm"	388.2 388.2 "5000 *W/m^2/K" "0.41796 / GJ"
    cold  "ColdWater@32.2degC"  305.2 305.2 "500 *W/m^2/K" "0.0668737 / GJ"
    cold  "Ammonia@1degC"	274.00 274.00 "500 *W/m^2/K" "1.65035 / GJ"
    cold  "Ammonia@-17.68degC" 	255.32 255.32 "500 *W/m^2/K" "2.96871 / GJ"
    cold  "Ammonia@-21.67degC"	251.33 251.33 "500 *W/m^2/K" "3.96226 / GJ"
end
#
# the only processing technology is a distillation unit for which we
# specify a range of pressure levels which hopefully matches the range
# defined for streams.
#
Distillation dist
  LogReal P "1 *atm" "30 *atm" 4
end
#
# and we define a product tank which accepts any stream which has one
# component with greater than 90% purity.
#
ProductTank pure
  Expression spec "$(x>0.90)"
  # The unit must be marked as interesting to indicate that any
  # path in the search graph which terminates at one of these
  # nodes is an interesting path, i.e. one that leads to a
  # desired product.
  interesting		# interesting leaf node for n-best diversity
end
#
# we also need at least one feed tank for the raw material. the feed
# stream defined above is associated with this feed tank.
#
FeedTank feedTank
  Stream feed feed
end
#
# we will ask for solutions to be ranked in three separate lists, the
# first according to capital cost, the second according to operating
# cost, and the third a combination of the two. Each criterion is
# given a name, the type of operation required to combine criteria
# values from different sources (options are sum or max), and the
# actual expression for evaluating the criterion. The variables
# "opercost" and "capcost" are used for operating and capital costs
# respectively by all the standard unit models (and heat exchangers)
# in the FiSH distribution.
#
Criteria criteria
  criterion Capital sum capcost
  criterion Operating sum opercost
  criterion Annualized sum "capcost/2.0 + opercost"
end
#
# before attempting a synthesis problem, we tell the system the
# objects to use for all the global settings which affect the
# synthesis procedures.
#
Data
	utils utils		# which utilities object to use
	criteria criteria	# the ranking criteria
	# we now specify the list of units which are allowed for
	# processing
	unit dist		# distillation
	unit pure		# and pure product tanks
	unit feedTank		# and the feed tank
	print			# output all global settings
end
#
# now we actually define the synthesis problem based on the stream and
# units defined above. The number of best solutions to generate is
# specified in the command line (although it could be specified
# directly in this input file using, for instance, " nbest 3 ".
#
# a different problem class is used for this example because we want
# to study the potential for heat integration. this is done using the
# "autovhl" command available in the Qualified problem class.
#
QualifiedProblem rathore_hen
	# enable automated heat integration mode. heat integration is
	# tackled through a coarse discretization procedure which
	# discretizes the temperatures and duties allowed for internal
	# heat exchange. the first parameter to this command specifies
	# the number of temperature levels and the second the number
	# of duty levels. the actual values are determined
	# automatically using a simple data analysis procedure. the
	# data are generated using a non-heat integrated pass to the
	# problem.
	autovhl 2 1
	representation units	# include unit info in n-best diversity
	sud true		# save unit designs
	shd true		# and heat exchanger designs as well
	# solve the problem ...
	solve
	print			# and show the best solutions found
	print short		# showing the basic structure as well
	stats			# display some statistics about the search
	export			# generate the flowsheets
end
# and that's all!