A dynamic model for the prediction of flue gas carbon dioxide removal by the microalga Chlorella vulgaris in column photobioreactor

Abstract

In the present work, a dynamic mass-transfer model of the microalga Chlorella vulgaris flue gas sequestration system is proposed. Rate-based model emphasizes on the flue gas utilization as an input carbon source. Model is designed to simulate carbon dioxide (CO2) mitigation in the microalgal semi-batch cultures continuously supplied with the real flue gas. Model is a mass balance based, and accounts for transport properties, thermodynamics, and absorption kinetics. Model is built-up of three equations describing the mass balances of the biomass and CO2 in the gas and liquid phases. Coupled equations of the model were solved with MATLAB and Simulink with the defined initial conditions and model parameters. Model was calibrated and validated with the experimental results from the cultured C. Vulgaris. Proposed model is an applicable tool for designing and controlling the biological CO2 fixation facilities using microalga cultures. Moreover, the model permits monitoring of the CO2 concentration in the gas and liquid phases. Proposed model shows that by manipulating the CO2 supply, the microalga C. Vulgaris culture has the potential of sequestration through the greenhouse gases on demand from source points. Keywords: Flue gas sequestration, Chlorella vulgaris, Growth rate modeling, Elimination capacity, Global warming