adding New Features to Binary Distillation (Getting Compositions given N_stages as input)

[omarbay]

New Feature to biosteam getting composition for monitoring purposes (Reverse_Mccabe_Thiele)

[omarbay]

Installation Guide

1. Clone the repository

   git clone <repository_url>
   cd <repository_name>

2. Ensure Python Version < 3.13 Check your Python version:

   python --version

   If you have Python 3.13 or later, install Python 3.12.9 and ensure it's used in the virtual environment.

3. Create and Activate a Virtual Environment

   python -m venv venv  
   source venv/bin/activate  # On macOS/Linux  
   venv\Scripts\activate     # On Windows  

4. Install a Compatible Thermosteam Version for This Biosteam Version
   Run the following commands:

   git submodule init  
   git submodule update  # (This may take a long time. To speed it up, consider removing 'Bioindustrial-park' and 'How2STEAM' from the .gitmodules file after initialization.)
   cd thermosteam  
   pip install .
   cd ..

5. Install Dependencies from requirements.txt

   pip install -r requirements.txt

6. Run the Example Script

   python binary-distillation-example.py

Issues Encountered

Biosteam Module Compatibility

Issue: Some requirements in the Biosteam module require a Python version lower than 3.13 (latest: 3.13.2).
Fix: Install Python 3.12.9.

Thermosteam Version Compatibility

Issue: The Thermosteam version available on pip (0.51.5) is not compatible with the Biosteam version on GitHub, which requires Thermosteam 0.51.6.
Fix: Clone the Thermosteam submodule from Git and uninstall the pip version.
Commands:

git submodule init  
git submodule update  # (This may take too long. To speed up future updates, consider removing 'Bioindustrial-park' and 'How2STEAM' from the .gitmodules file after initialization.)
cd thermosteam  
pip install .

---

Modifications

Modified Functions (All in distillation.py)

• Distillation.__init__
• Distillation._set_distillation_product_specifications
• BinaryDistillation._run
• Distillation._run_binary_distillation_mass_balance
• Distillation._update_distillate_and_bottoms_temperature
• BinaryDistillation._design
• BinaryDistillation._run_McCabeThiele

New Functions

• BinaryDistillation._calculate_stages

  • Extracts the code responsible for calculating the number of stages from BinaryDistillation._run_McCabeThiele.
  • Returns the computed number of stages.

• BinaryDistillation._mccabe_thiele_find_X_bot

  • Performs a binary search on x_bot, validating it based on the provided number of stages.

• BinaryDistillation._mccabe_thiele_find_Y_top

  • Performs a binary search on y_top, validating it based on the provided number of stages.

Modifications

1. Distillation.__init__

• Added N_stages as a parameter in the class constructor (default: None).
• Passes N_stages to Distillation._set_distillation_product_specifications.

2. x_bot Setter

• Added an assertion to allow x_bot == None.

3. y_top Setter

• Added an assertion to allow y_top == None.

4. Distillation._set_distillation_product_specifications

• Added N_stages as a parameter.
• Introduced cases:
  • If N_stages and y_top are provided but x_bot is not.
  • If N_stages and x_bot are provided but y_top is not.

5. BinaryDistillation._run

• Added a condition to prevent calling Distillation._update_distillate_and_bottoms_temperature if x_bot or y_top is None.

6. Distillation._run_binary_distillation_mass_balance

• Added a condition to check if x_bot and y_top are not None before performing mass balance calculations.
• Replaced else with elif spec != 'Composition'.
• Moved the code from the previous else block into the above two cases.

7. BinaryDistillation._run_McCabeThiele

• Now handles three cases:
  • Case 1: If N_stages is None but x_bot and y_top are defined → Calls BinaryDistillation._calculate_stages.
  • Case 2: If x_bot is None but N_stages and y_top are defined → Calls BinaryDistillation._mccabe_thiele_find_X_bot.
  • Case 3: If y_top is None but N_stages and x_bot are defined → Calls BinaryDistillation._mccabe_thiele_find_Y_top.

[omarbay]

example of the new feature (binary-distillation-example.py)

from biosteam import Stream, settings
import biosteam as bst
bst.nbtutorial()

settings.set_thermo(['Water', 'Ethanol'])

feed = Stream('feed', Water=1.08e+03, Ethanol=586)
bp = feed.bubble_point_at_P()
feed.T = bp.T # Feed at bubble point temperature

D1 = bst.BinaryDistillation(
'D1', ins=feed,
outs=('distillate', 'bottoms_product'),
LHK=('Ethanol', 'Water'), # Light and heavy keys
y_top=0.79, # Light key composition at the distillate
x_bot=0.001, # Light key composition at the bottoms product
k=1.25, # Ratio of actual reflux over minimum reflux
is_divided=True, # Whether the rectifying and stripping sections are divided
)
D1.simulate()
D1.diagram(format='png')
D1.show()
D1.plot_stages()

Finds x_Bottom

D1 = bst.BinaryDistillation(
'D1', ins=feed,
outs=('distillate', 'bottoms_product'),
LHK=('Ethanol', 'Water'), # Light and heavy keys
y_top=0.79, # Light key composition at the distillate
k=1.25, # Ratio of actual reflux over minimum reflux
is_divided=True, # Whether the rectifying and stripping sections are divided
N_stages=31, # Number of stages
)
D1.simulate()
D1.diagram(format='png')
D1.show()
D1.plot_stages()

Finds y_top

D1 = bst.BinaryDistillation(
'D1', ins=feed,
outs=('distillate', 'bottoms_product'),
LHK=('Ethanol', 'Water'), # Light and heavy keys
x_bot=0.001, # Light key composition at the bottoms product
k=1.25, # Ratio of actual reflux over minimum reflux
is_divided=True, # Whether the rectifying and stripping sections are divided
N_stages=31, # Number of stages
)
D1.simulate()
D1.diagram(format='png')
D1.show()
D1.plot_stages()