Integrative cold plasma-biokinetic modelling for efficient removal of harmful algal blooms and biofuel valorization

A Cold Plasma (CP) biokinetic simulation model was developed to treat harmful algal blooms (HABs) and enable concurrent biofuel production using Spirulina platensis and River Seine Algal Blooms (RSAB). The process utilized a Pipe Plasma Air Reactor (PP-air R) with a corona discharge system operating at atmospheric pressure, 600 K, and 10 kV. Plasma performance was simulated using COMSOL Multiphysics, while algal physiological states such as normal (Ns), inhibition (Is), and excitation (Es) were modelled using status parameters α, β, and γ. A novel equation integrating the inhibition profile (If) with the growth rate (Rx) was solved using nonlinear regression in MATLAB. Results showed electron densities up to 1 × 10 11 m −3 and stable electron temperatures (<0.1 V), indicating reliable plasma behavior. The model showed high accuracy (R 2 = 0.99, 1 % error). Growth peaked at 0.19 g·L −1 ·d −1 under 72.7 μE·m −2 ·s −1 light intensity, while full inhibition occurred at 140 μE·m −2 ·s −1 . The CP system achieved 100 % removal efficiency with an energy cost of 0.69 USD·m −3 ·order −1 . Incorporating biofuel production from treated biomass reduced operational costs by 73.75 %. This integrated approach is both environmentally sustainable and economically feasible for HAB remediation and resource recovery. • Developed a novel cold plasma–biokinetic model for harmful algal bloom mitigation • Achieved 100 % algal removal using a Pipe Plasma Air Reactor at low energy cost • Integrated COMSOL and MATLAB simulations for model validation and optimization • Demonstrated 73.75 % cost reduction by coupling biofuel production with HAB treatment • Validated model showed excellent accuracy with R 2 = 0.99 and p < 0.0001.