Potential of amyl alcohol mixtures derived from Scenedesmus quadricauda microalgae biomass as third generation bioenergy for compression ignition engine applications using multivariate-desirability analysis

This study is aimed at synthesizing amyl alcohol from Scenedesmus quadricauda third-generation microalgae biomass which is cultivated sustainably using reactor combinations and Ehrlich biosynthetic pathway. Systematic experimentation was carried out on a compression ignition engine at maximum throttle pedal position condition to assess the potential of amyl alcohol-diesel mixture combinations and to assess its environmental impact at different loads. Optimum mixture proportion of amyl alcohol-diesel blends were identified statistically using multivariate principal component and desirability analysis based on the experimental data acquired from the engine testbed. From the study, it was inferred that a dry biomass yield rate of 4.2 g/L was achieved when the light intensity was maintained at similar to 51-56 mu mol/m(2)/s in the in-situ raceway pond while cultivating Scenedesmus quadricauda. Experimentation showed that the fuel consumption reduced by 72.4% for AA20D80 at low-high load conditions. Improved combustion characteristics are achieved at higher concentrations of amyl alcohol operating at medium-high loads. The lowest smoke and NOX emission of 52.85 mg/m(3) and 104 ppm was observed for AA40D60 at no-load condition. Statistical analysis revealed that the optimal amyl alcohol-diesel mixture combinations to be AA20D80 with combined desirability of 0.497.

Automated summary

This study aimed to synthesize amyl alcohol from sustainably cultivated microalgae biomass using reactor combinations and Ehrlich biosynthetic pathway. Experiments on a compression ignition engine showed significant fuel consumption reduction for the amyl alcohol-diesel mixture at medium-high load conditions.