Microalgae to MCCA without external electron donor

This repository contains the simulation models and analysis for the research project: "Conversion of waste microalgae into caproic acid using anaerobic membrane bioreactors without external electron donors".

The models are built using BioSTEAM, a platform for the design, simulation, and techno-economic analysis (TEA) of biorefineries.

Overview

The project explores the production of medium-chain carboxylic acids (MCCAs), specifically caproic acid, from waste microalgae via anaerobic fermentation. A key feature of this process is the absence of external electron donor addition. This system present an anaerobic membrane bioreactor platform with integrating yeast to generate electron donors in situ.

Repository Structure

system.py: Main system for MCCA prodcution with yeast addition. The outcome of TEA can be found by running system.py

system_ethanol.py: Scenario with ethanol as an electron donor.

system_noCyeast.py: Scenario with yeast continuous addition

system_no_yeast.py: Scenarios without yeast addition.

lca.py: Module for performing Life Cycle Assessment.

streams.py: Definition of feedstock streams.

utils.py: Utility functions for cost and LCA calculations.

_chemicals.py: Chemical usage and their thermodynamic property definitions for the chemical species involved.

parameter_distributions_*.xlsx: Parameter distributions for uncertainty analysis.

Getting start

To run the simulations, you can use the provided system files as entry points. For example:

python system.py

To get LCA outcome, plese run the lca.py

python lca.py

Citation

If this repository is helpful to your research, please cite the following publication:

Shi X; Wei W; Zhao J; Li Y; Liu X, Xu J, Ni BJ, 2026, Conversion of waste microalgae into caproic acid using anaerobic membrane bioreactors without external electron donors, Green Chemistry (https://doi.org/10.1039/D6GC00346J)