Simple Flash Tank (Distillation)

The present repository scrap data from the NIST Webbook for Antoine constants and use them for calculating the vapor pressure and K-values for each of the components in a multicomponent stream line. An example file is included within and shows the general steps to solve a flash (and ideal) distillation problem.

The mathematical background is explained in my blog and below this line a brief description of the modules.

Parameter, Substance and Stream objects

Trying to use the OOP the repository are made of Classes that represent real concepts in real life.

1. Parameter: Represents process parameters as temperature, pressure and all measurements that need units to be full described

2. Substance: Represents real substances like water, propanol etc... Some of the methods allows user to obtain certain physical and chemical properties.

3. Stream: Represents stream lines, includes parameter of the stream and the substances transported.

External Libraries

• Beautiful Soup
• Numpy/Scipy

main.py File

from streams.substance import Substance
from streams.stream import Stream
from streams.parameter import Parameter
from opus.flash import Flash


"""
A flash chamber operating at 50°C and 200 kPa is separating 1000 kmol/h of a
feed that is 30 mol% propane, 10 mol% n-butane, 15 mol% n-pentane and 45 mol%
n-hexane. Find the product compositions and flow rates
"""

# Define substances
propane = Substance('Propane')
butane = Substance('Butane')
pentane = Substance('Pentane')
hexane = Substance('Hexane')
substances = [propane, butane, pentane, hexane]
composition = [0.3, 0.1, 0.15, 0.45]

# Define Parameters
temperature = Parameter('Temperature', 323, 'K')
pressure = Parameter('Pressure', 200, 'kPa')
flow_rate = Parameter('Mass Flow Rate', 1000,'kmol/h')

#Define Streams
inlet = Stream('Inlet', substances, flow_rate, composition, pressure, temperature)
vapor = Stream('Vapor', substances)
liquid = Stream('Liquid', substances)

# Define a Flash
flash = Flash('V-101', inlet, vapor, liquid)
flash.solve()
vapor = flash.vapor
liquid = flash.liquid

Results

Feed	Vapor	Liquid
F = 1000 kmol/h	V = 503.8 kmol/h	L = 496.2 kmol/h
z_propane = 0.3	y_propane = 0.534	x_propane = 0.062
z_butane = 0.1	y_butane = 0.142	x_butane = 0.058
z_pentane = 0.15	y_pentane = 0.133	x_pentane = 0.168
z_hexane = 0.45	y_hexane = 0.191	x_hexane = 0.713

More examples

There is a Jupyter Notebook renderer with two additional examples. You are able of read it here